WEBVTT NOTE duration:"01:06:48" NOTE recognizability:0.923 NOTE language:en-us NOTE Confidence: 0.857201046666667 00:00:00.000 --> 00:00:01.959 All right. Welcome NOTE Confidence: 0.95786455 00:00:01.960 --> 00:00:05.680 everyone. Thanks for coming today. NOTE Confidence: 0.95786455 00:00:05.680 --> 00:00:10.090 It is my honor to introduce my friend NOTE Confidence: 0.95786455 00:00:10.090 --> 00:00:13.420 and mentor and fellow neuropathologist, NOTE Confidence: 0.95786455 00:00:13.420 --> 00:00:15.520 Doctor Jeffrey Golden. NOTE Confidence: 0.95786455 00:00:15.520 --> 00:00:17.718 Some of you may know Jeff is NOTE Confidence: 0.95786455 00:00:17.718 --> 00:00:20.237 actually my PhD mentor and advisor NOTE Confidence: 0.95786455 00:00:20.237 --> 00:00:22.237 at University of Pennsylvania. NOTE Confidence: 0.95786455 00:00:22.240 --> 00:00:24.160 He's currently the director of NOTE Confidence: 0.95786455 00:00:24.160 --> 00:00:26.080 the Burns and Allen Research. NOTE Confidence: 0.95786455 00:00:26.080 --> 00:00:28.816 Institute at Cedars Sinai and also the Vice NOTE Confidence: 0.95786455 00:00:28.816 --> 00:00:31.719 Dean of Research and Graduate Education. NOTE Confidence: 0.95786455 00:00:31.720 --> 00:00:33.730 Jeff I graduated from University NOTE Confidence: 0.95786455 00:00:33.730 --> 00:00:35.740 of Pennsylvania School of Medicine NOTE Confidence: 0.95786455 00:00:35.800 --> 00:00:38.236 and after that went on to do NOTE Confidence: 0.95786455 00:00:38.236 --> 00:00:39.280 his neuropathology fellowship NOTE Confidence: 0.95786455 00:00:39.280 --> 00:00:42.717 and and postdoc training at MGH. NOTE Confidence: 0.95786455 00:00:42.717 --> 00:00:45.216 And he did his postdoc in Connie NOTE Confidence: 0.95786455 00:00:45.216 --> 00:00:47.324 Sepco's lab and really launched NOTE Confidence: 0.95786455 00:00:47.324 --> 00:00:49.652 his career into studying the NOTE Confidence: 0.95786455 00:00:49.652 --> 00:00:52.072 cellular and molecular basis of NOTE Confidence: 0.95786455 00:00:52.072 --> 00:00:53.040 neurodevelopmental disorders. NOTE Confidence: 0.95786455 00:00:53.040 --> 00:00:54.598 He did. NOTE Confidence: 0.95786455 00:00:54.598 --> 00:00:56.788 Really pioneering work studying non NOTE Confidence: 0.95786455 00:00:56.788 --> 00:00:59.463 radial cell migration and its critical NOTE Confidence: 0.95786455 00:00:59.463 --> 00:01:02.090 role in interneuron migration during NOTE Confidence: 0.95786455 00:01:02.090 --> 00:01:04.790 neocortical development and his NOTE Confidence: 0.95786455 00:01:04.790 --> 00:01:07.644 research has made he's made really NOTE Confidence: 0.95786455 00:01:07.644 --> 00:01:09.148 many contributions in understanding NOTE Confidence: 0.95786455 00:01:09.148 --> 00:01:11.466 the molecular and cellular basis of NOTE Confidence: 0.95786455 00:01:11.466 --> 00:01:13.890 several malformations of cortical NOTE Confidence: 0.95786455 00:01:13.890 --> 00:01:16.410 development as well as epilepsy and NOTE Confidence: 0.95786455 00:01:16.410 --> 00:01:21.630 and other intellectual disorders. So I. NOTE Confidence: 0.95786455 00:01:21.630 --> 00:01:23.390 Won't really take up any more time, NOTE Confidence: 0.93773775 00:01:24.030 --> 00:01:25.230 but it's it's just NOTE Confidence: 0.935940714285714 00:01:26.070 --> 00:01:27.988 such an honor to have Jeff here. NOTE Confidence: 0.935940714285714 00:01:27.990 --> 00:01:29.310 We've been trying to get him here NOTE Confidence: 0.935940714285714 00:01:29.310 --> 00:01:31.710 since before the pandemic and so NOTE Confidence: 0.935940714285714 00:01:31.710 --> 00:01:33.494 finally he's here. I'm so pleased. NOTE Confidence: 0.935940714285714 00:01:33.494 --> 00:01:35.270 Please join me in welcoming him. NOTE Confidence: 0.932054222222222 00:01:39.990 --> 00:01:41.622 Well, first, thank you, NOTE Confidence: 0.932054222222222 00:01:41.622 --> 00:01:43.662 Paula V for the invitation. NOTE Confidence: 0.932054222222222 00:01:43.670 --> 00:01:46.158 This is I think the third of several NOTE Confidence: 0.932054222222222 00:01:46.158 --> 00:01:47.550 aborted attempts to get here. NOTE Confidence: 0.932054222222222 00:01:47.550 --> 00:01:49.694 And so I'm really pleased to be here. NOTE Confidence: 0.932054222222222 00:01:49.700 --> 00:01:51.660 And actually since the pandemic, NOTE Confidence: 0.932054222222222 00:01:51.660 --> 00:01:53.220 this is I think the only, NOTE Confidence: 0.932054222222222 00:01:53.220 --> 00:01:55.497 this is only my second visit to a university, NOTE Confidence: 0.932054222222222 00:01:55.500 --> 00:01:58.034 so it's great to see people in NOTE Confidence: 0.932054222222222 00:01:58.034 --> 00:02:00.490 person and be able to start feeling NOTE Confidence: 0.932054222222222 00:02:00.490 --> 00:02:02.620 like we're getting back to normal. NOTE Confidence: 0.932054222222222 00:02:02.620 --> 00:02:04.660 So today what I want to NOTE Confidence: 0.932054222222222 00:02:04.660 --> 00:02:06.740 do is take you through NOTE Confidence: 0.9452853 00:02:09.780 --> 00:02:11.220 we've been doing over. NOTE Confidence: 0.95635504 00:02:28.560 --> 00:02:30.040 Technology have started to really NOTE Confidence: 0.9352219 00:02:32.160 --> 00:02:32.840 just out NOTE Confidence: 0.80314445 00:02:35.040 --> 00:02:35.120 there NOTE Confidence: 0.926416425 00:02:38.340 --> 00:02:41.035 we go. So I like to start NOTE Confidence: 0.926416425 00:02:41.035 --> 00:02:42.059 out there was playing NOTE Confidence: 0.94226628 00:02:44.980 --> 00:02:46.420 that's good okay there we NOTE Confidence: 0.881803616363636 00:02:48.700 --> 00:02:51.780 go case and and what you see here is a mom NOTE Confidence: 0.934503085714286 00:02:54.820 --> 00:02:58.026 playing with her son in a crib. NOTE Confidence: 0.934503085714286 00:02:58.030 --> 00:03:00.271 The sun has a cap on which is an NOTE Confidence: 0.934503085714286 00:03:00.271 --> 00:03:02.427 EEG recording is a video EEG and NOTE Confidence: 0.934503085714286 00:03:02.427 --> 00:03:04.781 and you see him almost kind of NOTE Confidence: 0.934503085714286 00:03:04.781 --> 00:03:06.905 flop over as if almost playing. NOTE Confidence: 0.934503085714286 00:03:06.910 --> 00:03:10.385 But in fact this is a what's called NOTE Confidence: 0.934503085714286 00:03:10.385 --> 00:03:12.950 a drop seizure or a epileptic NOTE Confidence: 0.934503085714286 00:03:12.950 --> 00:03:16.150 seizure that this child has. NOTE Confidence: 0.934503085714286 00:03:16.150 --> 00:03:19.518 And the type of seizure actually pretends NOTE Confidence: 0.934503085714286 00:03:19.518 --> 00:03:23.186 a very poor prognosis for this individual. NOTE Confidence: 0.934503085714286 00:03:23.190 --> 00:03:26.414 This child will and actually did go on. NOTE Confidence: 0.934503085714286 00:03:26.420 --> 00:03:29.900 To have a variety of different types of NOTE Confidence: 0.934503085714286 00:03:29.900 --> 00:03:33.036 seizures and became increasingly severe. NOTE Confidence: 0.934503085714286 00:03:33.036 --> 00:03:35.058 Also had cognitive NOTE Confidence: 0.962057633333333 00:03:37.140 --> 00:03:39.540 disabilities and had NOTE Confidence: 0.962057633333333 00:03:39.540 --> 00:03:41.940 autism spectrum disorder. NOTE Confidence: 0.962057633333333 00:03:41.940 --> 00:03:43.780 And so from this very simple thing we NOTE Confidence: 0.905285902105263 00:03:51.540 --> 00:03:53.908 neurobiology that must underlie. NOTE Confidence: 0.905285902105263 00:03:53.908 --> 00:03:57.460 These defects and and that's really NOTE Confidence: 0.905285902105263 00:03:57.548 --> 00:04:00.098 what I've been thinking about for NOTE Confidence: 0.905285902105263 00:04:00.098 --> 00:04:01.884 most of my scientific career. NOTE Confidence: 0.905285902105263 00:04:01.884 --> 00:04:03.900 So let me just tell you a couple NOTE Confidence: 0.905285902105263 00:04:03.954 --> 00:04:05.616 basic things about epilepsy and then NOTE Confidence: 0.905285902105263 00:04:05.616 --> 00:04:07.420 we'll get into some other things. NOTE Confidence: 0.905285902105263 00:04:07.420 --> 00:04:09.304 It's actually pretty common. NOTE Confidence: 0.905285902105263 00:04:09.304 --> 00:04:11.659 It's more common than stroke, NOTE Confidence: 0.905285902105263 00:04:11.660 --> 00:04:13.820 which we hear about a lot. NOTE Confidence: 0.905285902105263 00:04:13.820 --> 00:04:17.660 It is actually about as prevalent as asthma, NOTE Confidence: 0.905285902105263 00:04:17.660 --> 00:04:19.658 which is heard about a lot. NOTE Confidence: 0.905285902105263 00:04:19.660 --> 00:04:24.704 So epilepsy is a major healthcare issue. NOTE Confidence: 0.905285902105263 00:04:24.704 --> 00:04:29.036 And it's really hard to control. NOTE Confidence: 0.58313337 00:04:32.240 --> 00:04:38.500 Most Asian even with extensive NOTE Confidence: 0.58313337 00:04:38.500 --> 00:04:41.744 multi drug therapy do not come under NOTE Confidence: 0.58313337 00:04:41.744 --> 00:04:44.558 control and only a subset of them NOTE Confidence: 0.58313337 00:04:44.558 --> 00:04:47.351 are able to be managed with surgery. NOTE Confidence: 0.58313337 00:04:47.360 --> 00:04:48.392 So there are some that can NOTE Confidence: 0.58313337 00:04:48.392 --> 00:04:49.080 be managed with surgery, NOTE Confidence: 0.58313337 00:04:49.080 --> 00:04:51.110 but it's just a subset. NOTE Confidence: 0.58313337 00:04:51.110 --> 00:04:54.030 So really we need to develop a NOTE Confidence: 0.58313337 00:04:54.030 --> 00:04:56.430 far better understanding of the, NOTE Confidence: 0.58313337 00:04:56.430 --> 00:04:58.510 the underlying biology to NOTE Confidence: 0.58313337 00:04:58.510 --> 00:05:01.110 really begin to think about NOTE Confidence: 0.58313337 00:05:01.110 --> 00:05:01.917 biologically relevant therapeutics. NOTE Confidence: 0.58313337 00:05:01.917 --> 00:05:03.531 So we can talk about that NOTE Confidence: 0.58313337 00:05:03.531 --> 00:05:04.789 a little bit at the end. NOTE Confidence: 0.914410145454545 00:05:06.830 --> 00:05:09.049 So what are the causes of epilepsy NOTE Confidence: 0.914410145454545 00:05:09.049 --> 00:05:10.470 where they're quite varied, NOTE Confidence: 0.914410145454545 00:05:10.470 --> 00:05:12.426 They include things like brain injury, NOTE Confidence: 0.914410145454545 00:05:12.430 --> 00:05:15.174 so trauma to the brain and lead NOTE Confidence: 0.914410145454545 00:05:15.174 --> 00:05:18.298 to its stroke tumors and there's a NOTE Confidence: 0.914410145454545 00:05:18.298 --> 00:05:20.733 variety of different genetic defects. NOTE Confidence: 0.914410145454545 00:05:20.740 --> 00:05:22.456 But at least 50% of them, NOTE Confidence: 0.914410145454545 00:05:22.460 --> 00:05:24.336 we really don't know the underlying cause, NOTE Confidence: 0.914410145454545 00:05:24.340 --> 00:05:26.384 although it's believed that NOTE Confidence: 0.914410145454545 00:05:26.384 --> 00:05:28.939 many of those are genetic. NOTE Confidence: 0.914410145454545 00:05:28.940 --> 00:05:31.124 And that's really where this is NOTE Confidence: 0.914410145454545 00:05:31.124 --> 00:05:33.954 led me to kind of start thinking NOTE Confidence: 0.914410145454545 00:05:33.954 --> 00:05:36.540 about this and and this started NOTE Confidence: 0.914410145454545 00:05:36.540 --> 00:05:39.004 a number of years ago when I got NOTE Confidence: 0.914410145454545 00:05:39.004 --> 00:05:42.220 invited to give a talk at a. NOTE Confidence: 0.914410145454545 00:05:42.220 --> 00:05:44.752 Early infantile epileptic encephalopathy, NOTE Confidence: 0.914410145454545 00:05:44.752 --> 00:05:47.370 it's a type of syndrome that you NOTE Confidence: 0.914410145454545 00:05:47.370 --> 00:05:49.176 see and at the time I, I, NOTE Confidence: 0.914410145454545 00:05:49.176 --> 00:05:50.832 I started looking and I asked NOTE Confidence: 0.914410145454545 00:05:50.832 --> 00:05:52.220 the question well how many, NOTE Confidence: 0.914410145454545 00:05:52.220 --> 00:05:54.005 what do we know about the genes NOTE Confidence: 0.914410145454545 00:05:54.005 --> 00:05:55.761 that are involved at that time And NOTE Confidence: 0.914410145454545 00:05:55.761 --> 00:05:57.461 this list is much longer but this NOTE Confidence: 0.914410145454545 00:05:57.461 --> 00:05:59.388 is where I started and and at the NOTE Confidence: 0.914410145454545 00:05:59.388 --> 00:06:00.840 time there was just this relatively NOTE Confidence: 0.914410145454545 00:06:00.889 --> 00:06:02.599 small number of genes that are NOTE Confidence: 0.914410145454545 00:06:02.599 --> 00:06:03.986 involved there's there's now at NOTE Confidence: 0.914410145454545 00:06:03.986 --> 00:06:06.455 least 152 genes involved in or NOTE Confidence: 0.914410145454545 00:06:06.455 --> 00:06:08.972 associated with epilepsy and and I. NOTE Confidence: 0.914410145454545 00:06:08.972 --> 00:06:11.276 I just started kind of thinking NOTE Confidence: 0.914410145454545 00:06:11.276 --> 00:06:13.655 about this was kind of my own Geo, NOTE Confidence: 0.914410145454545 00:06:13.660 --> 00:06:15.740 my own you know, NOTE Confidence: 0.914410145454545 00:06:15.740 --> 00:06:19.844 kind of analysis and I was able to kind NOTE Confidence: 0.914410145454545 00:06:19.844 --> 00:06:23.939 of orc or divide them up into nuclear genes, NOTE Confidence: 0.914410145454545 00:06:23.940 --> 00:06:26.139 membrane associated genes. NOTE Confidence: 0.914410145454545 00:06:26.139 --> 00:06:29.800 These are mostly receptors, NOTE Confidence: 0.914410145454545 00:06:29.800 --> 00:06:32.880 transporters and channels, NOTE Confidence: 0.914410145454545 00:06:32.880 --> 00:06:34.500 cytoplasmic proteins. NOTE Confidence: 0.914410145454545 00:06:34.500 --> 00:06:36.930 And then interestingly, NOTE Confidence: 0.914410145454545 00:06:36.930 --> 00:06:38.830 a number of mitochondrial NOTE Confidence: 0.914410145454545 00:06:38.830 --> 00:06:40.730 disease genes came up. NOTE Confidence: 0.914410145454545 00:06:40.730 --> 00:06:42.737 And So what I'm going to do today is NOTE Confidence: 0.914410145454545 00:06:42.737 --> 00:06:44.945 take you through two of these because NOTE Confidence: 0.914410145454545 00:06:44.945 --> 00:06:46.545 we've started studying the nuclear NOTE Confidence: 0.914410145454545 00:06:46.545 --> 00:06:48.849 genes and I'm going to talk about a RX, NOTE Confidence: 0.914410145454545 00:06:48.850 --> 00:06:50.752 the first one in that line, NOTE Confidence: 0.914410145454545 00:06:50.752 --> 00:06:52.564 for quite a bit of time. NOTE Confidence: 0.914410145454545 00:06:52.570 --> 00:06:54.089 And then I'm going to switch over NOTE Confidence: 0.914410145454545 00:06:54.089 --> 00:06:55.924 and tell you a little bit about NOTE Confidence: 0.914410145454545 00:06:55.924 --> 00:06:57.339 mitochondrial ones and how those NOTE Confidence: 0.914410145454545 00:06:57.339 --> 00:06:58.996 actually came together in thinking NOTE Confidence: 0.914410145454545 00:06:58.996 --> 00:07:00.408 about these different disorders. NOTE Confidence: 0.936228169 00:07:02.450 --> 00:07:04.898 So just as a very brief primer to get NOTE Confidence: 0.936228169 00:07:04.898 --> 00:07:07.978 started, just to remind everyone about the NOTE Confidence: 0.936228169 00:07:07.978 --> 00:07:10.130 neocortex and for some of the audience, NOTE Confidence: 0.936228169 00:07:10.130 --> 00:07:11.090 I'm sure this is review, NOTE Confidence: 0.936228169 00:07:11.090 --> 00:07:13.650 but just to remind people, NOTE Confidence: 0.936228169 00:07:13.650 --> 00:07:14.770 I think you can see my pointer, NOTE Confidence: 0.936228169 00:07:14.770 --> 00:07:16.758 yeah, so layer one of the cortex NOTE Confidence: 0.936228169 00:07:16.758 --> 00:07:18.968 is known as the molecular layer. NOTE Confidence: 0.936228169 00:07:18.970 --> 00:07:20.400 This is in the mature NOTE Confidence: 0.936228169 00:07:20.400 --> 00:07:21.378 brain during development. NOTE Confidence: 0.936228169 00:07:21.378 --> 00:07:22.410 It's very important. NOTE Confidence: 0.936228169 00:07:22.410 --> 00:07:24.475 It's also known as the marginal zone NOTE Confidence: 0.936228169 00:07:24.475 --> 00:07:26.485 where there's a cell type called NOTE Confidence: 0.936228169 00:07:26.485 --> 00:07:28.260 the Chorizius neuron which makes. NOTE Confidence: 0.936228169 00:07:28.260 --> 00:07:30.042 Realin, which is important for the NOTE Confidence: 0.936228169 00:07:30.042 --> 00:07:31.580 organization of the sixth layer, NOTE Confidence: 0.936228169 00:07:31.580 --> 00:07:34.345 the laminar cortex layer two is known NOTE Confidence: 0.936228169 00:07:34.345 --> 00:07:37.099 as the external granular cell layer. NOTE Confidence: 0.936228169 00:07:37.100 --> 00:07:39.858 This is the mostly an input layer, NOTE Confidence: 0.936228169 00:07:39.860 --> 00:07:44.308 a local input layer to the neocortex layer NOTE Confidence: 0.936228169 00:07:44.308 --> 00:07:47.480 three is the external pyramidal cell layer. NOTE Confidence: 0.936228169 00:07:47.480 --> 00:07:51.113 Now I want to take this moment to say NOTE Confidence: 0.936228169 00:07:51.113 --> 00:07:53.738 that all layers have both excited to NOTE Confidence: 0.936228169 00:07:53.740 --> 00:07:56.220 have pyramidal and granular neurons. NOTE Confidence: 0.936228169 00:07:56.220 --> 00:07:58.326 It's just the relative distribution that NOTE Confidence: 0.936228169 00:07:58.326 --> 00:08:00.966 give rise to it being an an external, NOTE Confidence: 0.936228169 00:08:00.966 --> 00:08:02.964 I'm sorry, a granular layer versus NOTE Confidence: 0.936228169 00:08:02.964 --> 00:08:04.536 a paramidal cell layer. NOTE Confidence: 0.936228169 00:08:04.536 --> 00:08:07.888 So we have an external paramidal cell layer, NOTE Confidence: 0.936228169 00:08:07.888 --> 00:08:08.824 layer 3. NOTE Confidence: 0.936228169 00:08:08.824 --> 00:08:11.580 Then you have a internal granular NOTE Confidence: 0.936228169 00:08:11.580 --> 00:08:14.220 cell layer which is layer 4. NOTE Confidence: 0.936228169 00:08:14.220 --> 00:08:15.860 These layers actually define NOTE Confidence: 0.936228169 00:08:15.860 --> 00:08:17.500 the different cortical regions. NOTE Confidence: 0.936228169 00:08:17.500 --> 00:08:18.148 So for example, NOTE Confidence: 0.936228169 00:08:18.148 --> 00:08:19.660 if you look in the visual cortex, NOTE Confidence: 0.936228169 00:08:19.660 --> 00:08:21.180 this is from motor cortex, NOTE Confidence: 0.936228169 00:08:21.180 --> 00:08:23.140 if you look at the visual cortex. NOTE Confidence: 0.936228169 00:08:23.140 --> 00:08:25.390 Layer 4 is dramatically expanded and NOTE Confidence: 0.936228169 00:08:25.390 --> 00:08:28.138 it's the major input from the thalamus, NOTE Confidence: 0.936228169 00:08:28.140 --> 00:08:30.744 whereas in the motor cortex there's NOTE Confidence: 0.936228169 00:08:30.744 --> 00:08:33.099 almost no layer four at all. NOTE Confidence: 0.936228169 00:08:33.100 --> 00:08:34.744 In contrast, layer 5, NOTE Confidence: 0.936228169 00:08:34.744 --> 00:08:36.660 which is your primary NOTE Confidence: 0.924419793333333 00:08:39.220 --> 00:08:40.952 output pyramidal cell layer, NOTE Confidence: 0.924419793333333 00:08:40.952 --> 00:08:42.280 that goes, for example, NOTE Confidence: 0.924419793333333 00:08:42.280 --> 00:08:43.660 the large bed cells that go NOTE Confidence: 0.924419793333333 00:08:43.660 --> 00:08:44.940 down in the spinal cord, NOTE Confidence: 0.924419793333333 00:08:44.940 --> 00:08:47.220 those are all in layer 5. NOTE Confidence: 0.924419793333333 00:08:47.220 --> 00:08:48.860 Those project to other parts of the brain, NOTE Confidence: 0.924419793333333 00:08:48.860 --> 00:08:50.210 including to the other side NOTE Confidence: 0.924419793333333 00:08:50.210 --> 00:08:52.744 of the brain and then layer 6. NOTE Confidence: 0.924419793333333 00:08:52.744 --> 00:08:55.330 Which is against the white matter. NOTE Confidence: 0.924419793333333 00:08:55.330 --> 00:08:57.738 This is the what's known as the multiform NOTE Confidence: 0.924419793333333 00:08:57.738 --> 00:08:59.673 or fusiform layer and it consists NOTE Confidence: 0.924419793333333 00:08:59.673 --> 00:09:01.581 of a variety of different neuronal NOTE Confidence: 0.924419793333333 00:09:01.643 --> 00:09:03.687 types and has both input and output. NOTE Confidence: 0.924419793333333 00:09:03.690 --> 00:09:06.050 And then below that is the white matter. NOTE Confidence: 0.924419793333333 00:09:06.050 --> 00:09:08.490 So that's the six layers of the cortex. NOTE Confidence: 0.924419793333333 00:09:08.490 --> 00:09:11.010 And these layers are composed, NOTE Confidence: 0.924419793333333 00:09:11.010 --> 00:09:13.650 as I said of of these granular neurons, NOTE Confidence: 0.924419793333333 00:09:13.650 --> 00:09:17.094 here labeled non spining neurons and the NOTE Confidence: 0.924419793333333 00:09:17.094 --> 00:09:20.724 spining neurons or the pyramidal cells now. NOTE Confidence: 0.924419793333333 00:09:20.724 --> 00:09:23.568 These two cell types compose the NOTE Confidence: 0.924419793333333 00:09:23.570 --> 00:09:25.845 major 2 cell types in the cortex, NOTE Confidence: 0.924419793333333 00:09:25.850 --> 00:09:26.960 the excitatory neurons, NOTE Confidence: 0.924419793333333 00:09:26.960 --> 00:09:28.810 those are the spiny ones, NOTE Confidence: 0.924419793333333 00:09:28.810 --> 00:09:31.090 they use glutamate as a neurotransmitter, NOTE Confidence: 0.924419793333333 00:09:31.090 --> 00:09:34.548 and the non spiny or the inhibitory NOTE Confidence: 0.924419793333333 00:09:34.548 --> 00:09:36.890 interneurons which all use GABA. NOTE Confidence: 0.924419793333333 00:09:36.890 --> 00:09:37.928 But as you can see here, NOTE Confidence: 0.924419793333333 00:09:37.930 --> 00:09:39.315 there's actually many different forms NOTE Confidence: 0.924419793333333 00:09:39.315 --> 00:09:41.090 of each of these different neurons, NOTE Confidence: 0.924419793333333 00:09:41.090 --> 00:09:41.732 and there's. NOTE Confidence: 0.924419793333333 00:09:41.732 --> 00:09:44.300 Probably on the order of 30 to 40 NOTE Confidence: 0.924419793333333 00:09:44.371 --> 00:09:46.465 or more of the excitatory neurons NOTE Confidence: 0.924419793333333 00:09:46.465 --> 00:09:49.407 and in the order of 60 of different NOTE Confidence: 0.924419793333333 00:09:49.407 --> 00:09:51.252 types of inhibitory neurons or NOTE Confidence: 0.924419793333333 00:09:51.252 --> 00:09:55.350 the these non spiny interneurons. NOTE Confidence: 0.924419793333333 00:09:55.350 --> 00:09:58.994 Normal cortical development requires NOTE Confidence: 0.924419793333333 00:09:58.994 --> 00:10:03.338 an integration of both of these NOTE Confidence: 0.924419793333333 00:10:03.338 --> 00:10:05.510 types of neurons. NOTE Confidence: 0.924419793333333 00:10:05.510 --> 00:10:07.568 If you don't have the excitatory NOTE Confidence: 0.924419793333333 00:10:07.568 --> 00:10:09.785 neurons and the inhibitory neurons you NOTE Confidence: 0.924419793333333 00:10:09.785 --> 00:10:11.740 get disruptions in normal cortical. NOTE Confidence: 0.924419793333333 00:10:11.740 --> 00:10:12.282 Functions, NOTE Confidence: 0.924419793333333 00:10:12.282 --> 00:10:14.992 circuits that result in functional NOTE Confidence: 0.924419793333333 00:10:14.992 --> 00:10:18.048 defects and those give rise to a NOTE Confidence: 0.924419793333333 00:10:18.048 --> 00:10:20.500 variety of different developmental disorders. NOTE Confidence: 0.924419793333333 00:10:20.500 --> 00:10:22.756 And what you can see here is the NOTE Confidence: 0.924419793333333 00:10:22.756 --> 00:10:24.624 different types of excitatory and NOTE Confidence: 0.924419793333333 00:10:24.624 --> 00:10:27.096 inhibitory neurons connect in different ways. NOTE Confidence: 0.924419793333333 00:10:27.100 --> 00:10:29.062 So there are some inhibitory neurons NOTE Confidence: 0.924419793333333 00:10:29.062 --> 00:10:31.304 like this green one that predominantly NOTE Confidence: 0.924419793333333 00:10:31.304 --> 00:10:34.325 function by connecting on the Axon and NOTE Confidence: 0.924419793333333 00:10:34.325 --> 00:10:37.379 the proximal Axon and the cell body, NOTE Confidence: 0.924419793333333 00:10:37.380 --> 00:10:39.230 whereas others are going to NOTE Confidence: 0.924419793333333 00:10:39.230 --> 00:10:40.710 connect more on dendrites. NOTE Confidence: 0.924419793333333 00:10:40.710 --> 00:10:43.310 And some just on the cell body itself, NOTE Confidence: 0.924419793333333 00:10:43.310 --> 00:10:45.042 like this purple one. NOTE Confidence: 0.924419793333333 00:10:45.042 --> 00:10:48.364 And these are all required to appropriately NOTE Confidence: 0.924419793333333 00:10:48.364 --> 00:10:51.549 modulate circuits in the brain. NOTE Confidence: 0.924419793333333 00:10:51.550 --> 00:10:53.692 So you need all these different types NOTE Confidence: 0.924419793333333 00:10:53.692 --> 00:10:55.635 to get the appropriate development NOTE Confidence: 0.924419793333333 00:10:55.635 --> 00:10:58.503 and function of the cerebral cortex. NOTE Confidence: 0.917191383333333 00:11:01.590 --> 00:11:04.020 Well, what's interesting also about this NOTE Confidence: 0.917191383333333 00:11:04.020 --> 00:11:07.338 is that these two different neuronal types NOTE Confidence: 0.917191383333333 00:11:07.338 --> 00:11:10.043 come from different progenitor zones. NOTE Confidence: 0.917191383333333 00:11:10.050 --> 00:11:14.210 Now in the for the cortical excitatory NOTE Confidence: 0.917191383333333 00:11:14.210 --> 00:11:16.302 neurons, they are essentially NOTE Confidence: 0.917191383333333 00:11:16.302 --> 00:11:18.486 all driven from or derived from NOTE Confidence: 0.917191383333333 00:11:18.486 --> 00:11:20.610 the cortical ventricular zone, NOTE Confidence: 0.917191383333333 00:11:20.610 --> 00:11:23.352 that dorsal portion of progenitor cells NOTE Confidence: 0.917191383333333 00:11:23.352 --> 00:11:26.790 that are along the ventricle and these NOTE Confidence: 0.917191383333333 00:11:26.790 --> 00:11:29.250 cells divide and they migrate out. NOTE Confidence: 0.917191383333333 00:11:29.250 --> 00:11:31.329 This a lot of this work fundamentally NOTE Confidence: 0.917191383333333 00:11:31.329 --> 00:11:33.202 done by Doctor Rakesh who's sitting NOTE Confidence: 0.917191383333333 00:11:33.202 --> 00:11:34.737 here in the front row. NOTE Confidence: 0.917191383333333 00:11:34.740 --> 00:11:37.220 Has shown that these cells migrate out the NOTE Confidence: 0.917191383333333 00:11:37.220 --> 00:11:39.655 first form of what's called a preplate A, NOTE Confidence: 0.917191383333333 00:11:39.660 --> 00:11:40.832 the call ritzius neuron, NOTE Confidence: 0.917191383333333 00:11:40.832 --> 00:11:42.297 and then a subplate neuron, NOTE Confidence: 0.917191383333333 00:11:42.300 --> 00:11:45.420 which is really important for the NOTE Confidence: 0.917191383333333 00:11:45.420 --> 00:11:48.284 ultimate connection between the thalamic NOTE Confidence: 0.917191383333333 00:11:48.284 --> 00:11:51.214 nuclei and the cortical region. NOTE Confidence: 0.917191383333333 00:11:51.220 --> 00:11:52.480 So defining, for example, NOTE Confidence: 0.917191383333333 00:11:52.480 --> 00:11:54.370 the visual cortex in the lateral NOTE Confidence: 0.917191383333333 00:11:54.430 --> 00:11:55.300 geniculate body. NOTE Confidence: 0.917191383333333 00:11:55.300 --> 00:11:56.818 For those connections to be made, NOTE Confidence: 0.917191383333333 00:11:56.820 --> 00:11:59.380 it requires those subplate neurons. NOTE Confidence: 0.917191383333333 00:11:59.380 --> 00:12:01.718 They that the call ritzius neuron and NOTE Confidence: 0.917191383333333 00:12:01.718 --> 00:12:03.610 the subplate neuron are important. NOTE Confidence: 0.917191383333333 00:12:03.610 --> 00:12:06.410 We're also separating and the NOTE Confidence: 0.917191383333333 00:12:06.410 --> 00:12:07.530 definitive cortex, NOTE Confidence: 0.917191383333333 00:12:07.530 --> 00:12:10.050 that layer 2 through 6. NOTE Confidence: 0.917191383333333 00:12:10.050 --> 00:12:12.276 Fill in between those and they fill NOTE Confidence: 0.917191383333333 00:12:12.276 --> 00:12:15.078 in in an inverse pattern from the NOTE Confidence: 0.917191383333333 00:12:15.078 --> 00:12:17.730 deep layer to the superficial layer. NOTE Confidence: 0.917191383333333 00:12:17.730 --> 00:12:18.660 In mice, NOTE Confidence: 0.917191383333333 00:12:18.660 --> 00:12:20.985 all of the excitatory neurons NOTE Confidence: 0.917191383333333 00:12:20.985 --> 00:12:23.090 come from this region, NOTE Confidence: 0.917191383333333 00:12:23.090 --> 00:12:25.407 and it looks like in humans too, NOTE Confidence: 0.917191383333333 00:12:25.410 --> 00:12:25.998 inhibitory neurons, NOTE Confidence: 0.917191383333333 00:12:25.998 --> 00:12:28.350 which I'll show you on the next slide. NOTE Confidence: 0.917191383333333 00:12:28.350 --> 00:12:30.401 There may be some that are derived NOTE Confidence: 0.917191383333333 00:12:30.401 --> 00:12:32.205 from the ventricular zone in NOTE Confidence: 0.917191383333333 00:12:32.205 --> 00:12:34.404 the in the human dorsal cortex, NOTE Confidence: 0.917191383333333 00:12:34.404 --> 00:12:37.389 but it does not appear to be in the mouse. NOTE Confidence: 0.917191383333333 00:12:37.390 --> 00:12:40.267 In the human and in the mouse, NOTE Confidence: 0.917191383333333 00:12:40.270 --> 00:12:41.884 the vast majority are from another NOTE Confidence: 0.917191383333333 00:12:41.884 --> 00:12:43.629 progenitor region and I'll show you that. NOTE Confidence: 0.917191383333333 00:12:43.630 --> 00:12:45.830 Next I do want to just briefly mention, NOTE Confidence: 0.917191383333333 00:12:45.830 --> 00:12:47.104 because I'm going to talk about it, NOTE Confidence: 0.917191383333333 00:12:47.110 --> 00:12:48.870 there's an intermediate progenitor zone. NOTE Confidence: 0.917191383333333 00:12:48.870 --> 00:12:51.030 This is called the sub ventricular NOTE Confidence: 0.917191383333333 00:12:51.030 --> 00:12:53.910 zone and this is where cells. NOTE Confidence: 0.917191383333333 00:12:53.910 --> 00:12:55.970 Actually go from the ventricular NOTE Confidence: 0.917191383333333 00:12:55.970 --> 00:12:58.630 zone being a stem cell to this NOTE Confidence: 0.917191383333333 00:12:58.630 --> 00:13:01.205 this subventricular zone where they NOTE Confidence: 0.917191383333333 00:13:01.205 --> 00:13:03.265 form an intermediate progenitor. NOTE Confidence: 0.917191383333333 00:13:03.270 --> 00:13:05.820 Go through one or several divisions NOTE Confidence: 0.917191383333333 00:13:05.820 --> 00:13:07.682 before ultimately and exiting the cell NOTE Confidence: 0.917191383333333 00:13:07.682 --> 00:13:09.630 cycle and going up into the cortex. NOTE Confidence: 0.905435112 00:13:13.030 --> 00:13:16.350 Now this, this is the what I was showing you. NOTE Confidence: 0.905435112 00:13:16.350 --> 00:13:18.667 Here's the this is a hemi section. NOTE Confidence: 0.905435112 00:13:18.670 --> 00:13:20.650 Imagine this being a hemi NOTE Confidence: 0.905435112 00:13:20.650 --> 00:13:22.234 section through the brain. NOTE Confidence: 0.905435112 00:13:22.240 --> 00:13:24.354 And it could be any mammalian species. NOTE Confidence: 0.905435112 00:13:24.360 --> 00:13:26.152 And it's one side. NOTE Confidence: 0.905435112 00:13:26.152 --> 00:13:28.392 So this is the midline, NOTE Confidence: 0.905435112 00:13:28.400 --> 00:13:31.438 this is dorsal or the top, this is ventral, NOTE Confidence: 0.905435112 00:13:31.438 --> 00:13:33.274 the bottom and this is lateral. NOTE Confidence: 0.905435112 00:13:33.280 --> 00:13:34.184 The cortical ventricular zone NOTE Confidence: 0.905435112 00:13:34.184 --> 00:13:35.314 that I've been talking about, NOTE Confidence: 0.905435112 00:13:35.320 --> 00:13:36.490 where the excitatory NOTE Confidence: 0.905435112 00:13:36.490 --> 00:13:38.440 neurons come from is here. NOTE Confidence: 0.905435112 00:13:38.440 --> 00:13:40.135 And then there's this structure NOTE Confidence: 0.905435112 00:13:40.135 --> 00:13:41.830 known as the ganglionic eminence NOTE Confidence: 0.905435112 00:13:41.889 --> 00:13:43.639 in the ventral part of the brain. NOTE Confidence: 0.905435112 00:13:43.640 --> 00:13:45.105 This is where these inhibitory NOTE Confidence: 0.905435112 00:13:45.105 --> 00:13:46.277 neurons are derived from. NOTE Confidence: 0.905435112 00:13:46.280 --> 00:13:49.936 And what's interesting is that if you look. NOTE Confidence: 0.905435112 00:13:49.940 --> 00:13:50.888 Along the dorsal, NOTE Confidence: 0.905435112 00:13:50.888 --> 00:13:53.504 ventral axis from the neural at the beginning NOTE Confidence: 0.905435112 00:13:53.504 --> 00:13:56.256 of the nervous system in this neural tube, NOTE Confidence: 0.905435112 00:13:56.260 --> 00:13:57.892 from dorsal to ventral, NOTE Confidence: 0.905435112 00:13:57.892 --> 00:14:00.636 you get different neural types defined NOTE Confidence: 0.905435112 00:14:00.636 --> 00:14:03.420 by different genetic pathways. NOTE Confidence: 0.905435112 00:14:03.420 --> 00:14:05.820 And you see that also in the forebrain. NOTE Confidence: 0.905435112 00:14:05.820 --> 00:14:07.136 So this is in the spinal cord, NOTE Confidence: 0.905435112 00:14:07.140 --> 00:14:08.148 but in the forebrain. NOTE Confidence: 0.905435112 00:14:08.148 --> 00:14:09.660 And there's specific genes that are NOTE Confidence: 0.905435112 00:14:09.712 --> 00:14:11.042 expressed in these different regions NOTE Confidence: 0.905435112 00:14:11.042 --> 00:14:12.763 that give rise to these different NOTE Confidence: 0.905435112 00:14:12.763 --> 00:14:14.498 progenitors and different cell types. NOTE Confidence: 0.905435112 00:14:14.500 --> 00:14:14.844 And again, NOTE Confidence: 0.905435112 00:14:14.844 --> 00:14:15.876 I'm going to come back to NOTE Confidence: 0.905435112 00:14:15.876 --> 00:14:16.740 talk about that as well. NOTE Confidence: 0.935781098888889 00:14:19.180 --> 00:14:21.016 So what does this look like in the human? NOTE Confidence: 0.935781098888889 00:14:21.020 --> 00:14:22.740 So on your left side, NOTE Confidence: 0.935781098888889 00:14:22.740 --> 00:14:27.380 that's a human about 7 1/2 weeks gestation. NOTE Confidence: 0.935781098888889 00:14:27.380 --> 00:14:30.076 And you can see the ganglionic eminence where NOTE Confidence: 0.935781098888889 00:14:30.076 --> 00:14:32.012 these inhibitory neurons are predominately NOTE Confidence: 0.935781098888889 00:14:32.012 --> 00:14:34.017 coming from the ventricular zone. NOTE Confidence: 0.935781098888889 00:14:34.020 --> 00:14:36.334 And this here is the preplate and NOTE Confidence: 0.935781098888889 00:14:36.334 --> 00:14:37.738 you can see the preplate forming, NOTE Confidence: 0.935781098888889 00:14:37.740 --> 00:14:39.072 it's a little larger, NOTE Confidence: 0.935781098888889 00:14:39.072 --> 00:14:41.540 It actually starts in the ventrilateral NOTE Confidence: 0.935781098888889 00:14:41.540 --> 00:14:45.292 location and it moves. Moves up, NOTE Confidence: 0.935781098888889 00:14:45.292 --> 00:14:47.860 so it doesn't all develop at the same time. NOTE Confidence: 0.935781098888889 00:14:47.860 --> 00:14:50.338 It also goes from anterior to posterior, NOTE Confidence: 0.935781098888889 00:14:50.340 --> 00:14:51.828 so you can see that in NOTE Confidence: 0.935781098888889 00:14:51.828 --> 00:14:52.820 the very dorsal regions, NOTE Confidence: 0.935781098888889 00:14:52.820 --> 00:14:54.296 there's not even a preplate yet. NOTE Confidence: 0.935781098888889 00:14:54.300 --> 00:14:59.539 At 7 1/2 weeks by 20 weeks, NOTE Confidence: 0.935781098888889 00:14:59.540 --> 00:15:01.380 the station which is here, NOTE Confidence: 0.935781098888889 00:15:01.380 --> 00:15:02.540 you can see the hippocampus. NOTE Confidence: 0.935781098888889 00:15:02.540 --> 00:15:04.220 So we're looking at the temporal lobe, NOTE Confidence: 0.935781098888889 00:15:04.220 --> 00:15:07.140 and essentially all the neurons, NOTE Confidence: 0.935781098888889 00:15:07.140 --> 00:15:08.640 with a few exceptions, NOTE Confidence: 0.935781098888889 00:15:08.640 --> 00:15:10.515 are already in the cortex. NOTE Confidence: 0.935781098888889 00:15:10.520 --> 00:15:11.820 So they've migrated out, NOTE Confidence: 0.935781098888889 00:15:11.820 --> 00:15:13.520 but they haven't yet differentiated NOTE Confidence: 0.935781098888889 00:15:13.520 --> 00:15:15.120 and defined themselves in NOTE Confidence: 0.935781098888889 00:15:15.120 --> 00:15:16.320 different laminar organization, NOTE Confidence: 0.935781098888889 00:15:16.320 --> 00:15:17.260 but they are molecularly NOTE Confidence: 0.935781098888889 00:15:17.260 --> 00:15:18.200 defined by that time. NOTE Confidence: 0.935781098888889 00:15:18.200 --> 00:15:18.804 All right. NOTE Confidence: 0.935781098888889 00:15:18.804 --> 00:15:21.320 So that's a little bit of a kind NOTE Confidence: 0.935781098888889 00:15:21.320 --> 00:15:23.720 of just background to get you NOTE Confidence: 0.935781098888889 00:15:23.720 --> 00:15:25.224 to thinking about the studies NOTE Confidence: 0.935781098888889 00:15:25.224 --> 00:15:26.880 I'm going to tell you about. NOTE Confidence: 0.935781098888889 00:15:26.880 --> 00:15:29.064 I'm going to start out telling you NOTE Confidence: 0.935781098888889 00:15:29.064 --> 00:15:30.370 about that transcription factor NOTE Confidence: 0.935781098888889 00:15:30.370 --> 00:15:31.984 that is associated with epilepsy. NOTE Confidence: 0.935781098888889 00:15:31.984 --> 00:15:33.360 It's actually associated with NOTE Confidence: 0.935781098888889 00:15:33.360 --> 00:15:35.520 structural defects of the brain as well. NOTE Confidence: 0.935781098888889 00:15:35.520 --> 00:15:36.822 It's called ARX. NOTE Confidence: 0.935781098888889 00:15:36.822 --> 00:15:38.558 Aristoless related homeobox gene, NOTE Confidence: 0.935781098888889 00:15:38.560 --> 00:15:41.530 so it's related to the Drosophila NOTE Confidence: 0.935781098888889 00:15:41.530 --> 00:15:44.595 ristolis gene and this gene is on NOTE Confidence: 0.935781098888889 00:15:44.595 --> 00:15:47.564 the X chromosome and in males what NOTE Confidence: 0.935781098888889 00:15:47.564 --> 00:15:51.652 you see is a spectrum of neurologic NOTE Confidence: 0.935781098888889 00:15:51.652 --> 00:15:53.712 and cognitive deficits and and NOTE Confidence: 0.935781098888889 00:15:53.712 --> 00:15:56.709 and I really was attracted to this NOTE Confidence: 0.935781098888889 00:15:56.709 --> 00:15:58.839 gene because of this spectrum. NOTE Confidence: 0.935781098888889 00:15:58.840 --> 00:16:01.400 So some mutations resulted in NOTE Confidence: 0.935781098888889 00:16:01.400 --> 00:16:04.770 hydrocephalus and and abnormal genitalia. NOTE Confidence: 0.935781098888889 00:16:04.770 --> 00:16:05.770 That's a pretty rare one. NOTE Confidence: 0.935781098888889 00:16:05.770 --> 00:16:07.156 What's most common was the second NOTE Confidence: 0.935781098888889 00:16:07.156 --> 00:16:09.770 one on there, something called X lag, NOTE Confidence: 0.935781098888889 00:16:09.770 --> 00:16:12.650 X link lizencephaly with ambiguous genitalia. NOTE Confidence: 0.935781098888889 00:16:12.650 --> 00:16:14.246 But you could also have a genesis, NOTE Confidence: 0.935781098888889 00:16:14.250 --> 00:16:15.720 the corpus callosum. NOTE Confidence: 0.935781098888889 00:16:15.720 --> 00:16:18.170 You could have infantile spasms. NOTE Confidence: 0.935781098888889 00:16:18.170 --> 00:16:19.654 That was what I showed you in NOTE Confidence: 0.935781098888889 00:16:19.654 --> 00:16:20.290 that child earlier. NOTE Confidence: 0.935781098888889 00:16:20.290 --> 00:16:22.570 That does have an ARX mutation NOTE Confidence: 0.935781098888889 00:16:22.570 --> 00:16:23.848 and a variety of other things, NOTE Confidence: 0.935781098888889 00:16:23.850 --> 00:16:26.330 down to intellectual disabilities NOTE Confidence: 0.935781098888889 00:16:26.330 --> 00:16:27.570 with seizures. NOTE Confidence: 0.93622824 00:16:29.890 --> 00:16:31.522 What I want to point out is that NOTE Confidence: 0.93622824 00:16:31.522 --> 00:16:33.379 at the top of this list are NOTE Confidence: 0.93622824 00:16:33.379 --> 00:16:34.769 structural defects of the brain, NOTE Confidence: 0.93622824 00:16:34.770 --> 00:16:37.780 lizencephaly and a genus of the corpus NOTE Confidence: 0.93622824 00:16:37.780 --> 00:16:40.562 callosum, and they have epilepsy NOTE Confidence: 0.93622824 00:16:40.562 --> 00:16:42.326 and intellectual disabilities. NOTE Confidence: 0.93622824 00:16:42.330 --> 00:16:44.570 At the bottom of the list are brains NOTE Confidence: 0.93622824 00:16:44.570 --> 00:16:47.938 that are structurally normal but NOTE Confidence: 0.93622824 00:16:47.938 --> 00:16:49.978 have the exact same intellectual NOTE Confidence: 0.93622824 00:16:49.978 --> 00:16:51.202 disabilities and epilepsy, NOTE Confidence: 0.93622824 00:16:51.210 --> 00:16:54.045 presenting at almost the exact same time. NOTE Confidence: 0.93622824 00:16:54.050 --> 00:16:55.324 And this was really curious to me. NOTE Confidence: 0.93622824 00:16:55.330 --> 00:16:58.018 How can you have these two different? NOTE Confidence: 0.93622824 00:16:58.020 --> 00:16:58.875 Kind of phenotypes, NOTE Confidence: 0.93622824 00:16:58.875 --> 00:17:00.300 one with a structurally abnormal NOTE Confidence: 0.93622824 00:17:00.300 --> 00:17:02.017 brain and one with a normal brain, NOTE Confidence: 0.93622824 00:17:02.020 --> 00:17:05.380 what's structurally normal based on MRI NOTE Confidence: 0.93622824 00:17:05.380 --> 00:17:09.778 and have the same neurologic presentation. NOTE Confidence: 0.93622824 00:17:09.780 --> 00:17:11.684 And I want to try and address that NOTE Confidence: 0.93622824 00:17:11.684 --> 00:17:13.848 and I hope by the end of today I NOTE Confidence: 0.93622824 00:17:13.848 --> 00:17:15.977 will be able to have addressed that. NOTE Confidence: 0.93622824 00:17:15.980 --> 00:17:17.708 I will say that females were NOTE Confidence: 0.93622824 00:17:17.708 --> 00:17:19.979 thought to have a genesis of the NOTE Confidence: 0.93622824 00:17:19.979 --> 00:17:21.739 corpus callosum in some cases, NOTE Confidence: 0.93622824 00:17:21.740 --> 00:17:23.188 otherwise they were normal. NOTE Confidence: 0.93622824 00:17:23.188 --> 00:17:24.998 We have shown in publications NOTE Confidence: 0.93622824 00:17:24.998 --> 00:17:26.880 that that's actually not true. NOTE Confidence: 0.93622824 00:17:26.880 --> 00:17:28.320 I'm not going to talk about females today, NOTE Confidence: 0.93622824 00:17:28.320 --> 00:17:31.122 but I'm happy to talk if you want to at the NOTE Confidence: 0.93622824 00:17:31.122 --> 00:17:33.754 end about the genetics and how that happens. NOTE Confidence: 0.93622824 00:17:33.760 --> 00:17:34.960 So let's talk about a RX. NOTE Confidence: 0.93622824 00:17:34.960 --> 00:17:37.636 It's a, it's got 5 exons. NOTE Confidence: 0.93622824 00:17:37.640 --> 00:17:38.912 The first, sorry, NOTE Confidence: 0.93622824 00:17:38.912 --> 00:17:41.880 the 2nd exon at the very end. NOTE Confidence: 0.93622824 00:17:41.880 --> 00:17:42.908 The second exon's the NOTE Confidence: 0.93622824 00:17:42.908 --> 00:17:44.193 largest at the very end. NOTE Confidence: 0.93622824 00:17:44.200 --> 00:17:47.040 It has the beginning of its paired like NOTE Confidence: 0.93622824 00:17:47.040 --> 00:17:48.657 transcription homeo domain component. NOTE Confidence: 0.93622824 00:17:48.657 --> 00:17:52.210 So it's got a paired like homeo domain. NOTE Confidence: 0.93622824 00:17:52.210 --> 00:17:53.645 It's at the end of the second, NOTE Confidence: 0.93622824 00:17:53.650 --> 00:17:55.702 going through the 3rd and into NOTE Confidence: 0.93622824 00:17:55.702 --> 00:17:57.809 the beginning of the 4th exons, NOTE Confidence: 0.93622824 00:17:57.810 --> 00:17:59.610 but I also and and and. NOTE Confidence: 0.93622824 00:17:59.610 --> 00:18:01.535 So mutations at the top of that NOTE Confidence: 0.93622824 00:18:01.535 --> 00:18:03.528 which are frame shift or deletions, NOTE Confidence: 0.93622824 00:18:03.530 --> 00:18:05.430 give you that very severe NOTE Confidence: 0.93622824 00:18:05.430 --> 00:18:07.330 structural defect of the brain, NOTE Confidence: 0.93622824 00:18:07.330 --> 00:18:10.658 including the lizencephaly and NOTE Confidence: 0.93622824 00:18:10.658 --> 00:18:13.890 the agents of the corpus callosum. NOTE Confidence: 0.93622824 00:18:13.890 --> 00:18:16.795 But at the bottom, I'm not sure. NOTE Confidence: 0.93622824 00:18:16.800 --> 00:18:19.040 Why the lettering didn't come out right, NOTE Confidence: 0.93622824 00:18:19.040 --> 00:18:22.491 but it's at the bottom are some NOTE Confidence: 0.93622824 00:18:22.491 --> 00:18:24.592 interesting mutations that are NOTE Confidence: 0.93622824 00:18:24.592 --> 00:18:27.262 point mutations in very highly NOTE Confidence: 0.93622824 00:18:27.262 --> 00:18:30.140 conserved amino acids and also NOTE Confidence: 0.93622824 00:18:30.140 --> 00:18:32.480 these alanine tract expansion. NOTE Confidence: 0.93622824 00:18:32.480 --> 00:18:35.600 So ARX has four alanine tracts in it. NOTE Confidence: 0.949198762222222 00:18:38.120 --> 00:18:39.275 We really don't know much NOTE Confidence: 0.949198762222222 00:18:39.275 --> 00:18:40.199 about these alanine tracts, NOTE Confidence: 0.949198762222222 00:18:40.200 --> 00:18:42.795 but we now know that there's about 450 NOTE Confidence: 0.949198762222222 00:18:42.795 --> 00:18:44.925 annotated genes in the human genome NOTE Confidence: 0.949198762222222 00:18:44.925 --> 00:18:47.558 that have an alanine tract in them. NOTE Confidence: 0.949198762222222 00:18:47.560 --> 00:18:49.360 75% of those are transcription factors. NOTE Confidence: 0.949198762222222 00:18:49.360 --> 00:18:51.352 So we think that it has something to NOTE Confidence: 0.949198762222222 00:18:51.352 --> 00:18:53.440 do with transcriptional regulation. NOTE Confidence: 0.949198762222222 00:18:53.440 --> 00:18:58.515 And there's now 9 or 10 genes that NOTE Confidence: 0.949198762222222 00:18:58.515 --> 00:19:01.400 have an alanine tract expansion NOTE Confidence: 0.949198762222222 00:19:01.400 --> 00:19:04.528 like you see in glutamine tract NOTE Confidence: 0.949198762222222 00:19:04.528 --> 00:19:06.320 expansions like Huntington's disease, NOTE Confidence: 0.949198762222222 00:19:06.320 --> 00:19:09.519 Kennedy syndrome, some of the HS P's, NOTE Confidence: 0.943838304444445 00:19:11.600 --> 00:19:13.765 those expansions in alanine tracts NOTE Confidence: 0.943838304444445 00:19:13.765 --> 00:19:15.497 though are relatively small. NOTE Confidence: 0.943838304444445 00:19:15.500 --> 00:19:18.140 On the order of three to NOTE Confidence: 0.943838304444445 00:19:18.140 --> 00:19:19.460 10 additional alanines. NOTE Confidence: 0.943838304444445 00:19:19.460 --> 00:19:21.692 And unlike the Huntington's disease and NOTE Confidence: 0.943838304444445 00:19:21.692 --> 00:19:24.636 some of the others that show anticipation NOTE Confidence: 0.943838304444445 00:19:24.636 --> 00:19:27.414 with very long glutamine tract expansions, NOTE Confidence: 0.943838304444445 00:19:27.420 --> 00:19:30.885 these are very short and they're all NOTE Confidence: 0.943838304444445 00:19:30.885 --> 00:19:33.951 developmental, they're not neurodegenerative, NOTE Confidence: 0.943838304444445 00:19:33.951 --> 00:19:37.379 these are neurodevelopmental disorders. NOTE Confidence: 0.943838304444445 00:19:37.380 --> 00:19:39.802 So we were quite curious about them NOTE Confidence: 0.943838304444445 00:19:39.802 --> 00:19:43.020 because these give rise to the the same. NOTE Confidence: 0.943838304444445 00:19:43.020 --> 00:19:45.180 Intellectual disabilities and epilepsy, NOTE Confidence: 0.943838304444445 00:19:45.180 --> 00:19:47.830 but structurally normal brains and NOTE Confidence: 0.943838304444445 00:19:47.830 --> 00:19:51.260 I'll be telling you about that today. NOTE Confidence: 0.943838304444445 00:19:51.260 --> 00:19:53.696 So where is a RX expressed? NOTE Confidence: 0.943838304444445 00:19:53.700 --> 00:19:57.161 Well, work from John Rubenstein's lab out NOTE Confidence: 0.943838304444445 00:19:57.161 --> 00:19:58.988 in San Francisco showed that it's expressed NOTE Confidence: 0.943838304444445 00:19:58.988 --> 00:20:00.820 early on in the ganglionic eminence. NOTE Confidence: 0.943838304444445 00:20:00.820 --> 00:20:03.578 Here you can see by insight to NOTE Confidence: 0.943838304444445 00:20:03.578 --> 00:20:05.499 hybridization and throughout the cortex NOTE Confidence: 0.943838304444445 00:20:05.500 --> 00:20:08.013 and here we did an immunohistic chemistry NOTE Confidence: 0.943838304444445 00:20:08.013 --> 00:20:10.268 with an antibody that we developed. NOTE Confidence: 0.943838304444445 00:20:10.270 --> 00:20:11.894 And you can see that it's expressed NOTE Confidence: 0.943838304444445 00:20:11.894 --> 00:20:13.510 strongly in the ganglionic eminence as NOTE Confidence: 0.943838304444445 00:20:13.510 --> 00:20:15.547 well as in the cortical ventricular zone. NOTE Confidence: 0.943838304444445 00:20:15.550 --> 00:20:17.950 But if you look in the cerebral cortex, NOTE Confidence: 0.943838304444445 00:20:17.950 --> 00:20:19.990 it's only expressed in a subset of cells, NOTE Confidence: 0.943838304444445 00:20:19.990 --> 00:20:22.062 And this was the first clue that it NOTE Confidence: 0.943838304444445 00:20:22.062 --> 00:20:24.318 may be different in the inhibitory NOTE Confidence: 0.943838304444445 00:20:24.318 --> 00:20:25.986 in the excitatory neurons. NOTE Confidence: 0.943838304444445 00:20:25.990 --> 00:20:28.915 And it turns out that ARX is expressed in NOTE Confidence: 0.943838304444445 00:20:28.915 --> 00:20:32.064 all of the ventricular zone of the cortex, NOTE Confidence: 0.943838304444445 00:20:32.070 --> 00:20:34.222 but it turns off as soon as those NOTE Confidence: 0.943838304444445 00:20:34.222 --> 00:20:35.748 cells exit the cell cycle. NOTE Confidence: 0.943838304444445 00:20:35.750 --> 00:20:36.103 However, NOTE Confidence: 0.943838304444445 00:20:36.103 --> 00:20:37.868 in the inhibitory neurons coming NOTE Confidence: 0.943838304444445 00:20:37.868 --> 00:20:39.840 out of that ganglionic evidence. NOTE Confidence: 0.943838304444445 00:20:39.840 --> 00:20:42.840 It stays on all the way into adulthood. NOTE Confidence: 0.943838304444445 00:20:42.840 --> 00:20:45.240 So it seems to have different NOTE Confidence: 0.943838304444445 00:20:45.240 --> 00:20:47.282 role differential roles in these NOTE Confidence: 0.943838304444445 00:20:47.282 --> 00:20:49.466 two different stem cells all the NOTE Confidence: 0.943838304444445 00:20:49.466 --> 00:20:51.640 way into the mature neuron. NOTE Confidence: 0.943838304444445 00:20:51.640 --> 00:20:54.680 So to study this what we did is NOTE Confidence: 0.943838304444445 00:20:54.680 --> 00:20:56.919 we generated a mouse that had NOTE Confidence: 0.943838304444445 00:20:56.920 --> 00:20:59.237 a that that was a Flox mouse. NOTE Confidence: 0.943838304444445 00:20:59.240 --> 00:21:01.160 It has we inserted crease it NOTE Confidence: 0.943838304444445 00:21:01.160 --> 00:21:03.398 was on either side of Exxon two. NOTE Confidence: 0.943838304444445 00:21:03.400 --> 00:21:05.787 Remember Exxon two at the beginning of NOTE Confidence: 0.943838304444445 00:21:05.787 --> 00:21:08.277 the homeo domains when we remove Exxon 2. NOTE Confidence: 0.943838304444445 00:21:08.280 --> 00:21:10.400 It actually everything else is out of frame. NOTE Confidence: 0.943838304444445 00:21:10.400 --> 00:21:13.256 You have no homeo domain and we NOTE Confidence: 0.943838304444445 00:21:13.256 --> 00:21:15.959 believe this is a null mutation. NOTE Confidence: 0.943838304444445 00:21:15.960 --> 00:21:18.096 We could then cross this mouse NOTE Confidence: 0.943838304444445 00:21:18.096 --> 00:21:20.645 that we generated with a variety of NOTE Confidence: 0.943838304444445 00:21:20.645 --> 00:21:22.745 different Cree driver mice and we NOTE Confidence: 0.943838304444445 00:21:22.745 --> 00:21:25.461 could remove a RX from just excitatory NOTE Confidence: 0.943838304444445 00:21:25.461 --> 00:21:29.800 or just inhibitory mice, sorry cells. NOTE Confidence: 0.943838304444445 00:21:29.800 --> 00:21:31.396 Now to take one step back, NOTE Confidence: 0.943838304444445 00:21:31.400 --> 00:21:32.102 a knockout, NOTE Confidence: 0.943838304444445 00:21:32.102 --> 00:21:34.910 A germline knockout had been made by Doctor NOTE Confidence: 0.943838304444445 00:21:34.974 --> 00:21:37.396 Kitamura in Japan and that was lethal. NOTE Confidence: 0.943838304444445 00:21:37.400 --> 00:21:38.942 So we couldn't study any later NOTE Confidence: 0.943838304444445 00:21:38.942 --> 00:21:39.713 effects with it. NOTE Confidence: 0.943838304444445 00:21:39.720 --> 00:21:41.862 So we wanted to really hone down NOTE Confidence: 0.943838304444445 00:21:41.862 --> 00:21:43.600 on different regions of the brain. NOTE Confidence: 0.943838304444445 00:21:43.600 --> 00:21:44.360 So that's what we did. NOTE Confidence: 0.943838304444445 00:21:44.360 --> 00:21:47.438 So here we've crossed this mouse NOTE Confidence: 0.943838304444445 00:21:47.440 --> 00:21:49.180 with one that expresses creed NOTE Confidence: 0.943838304444445 00:21:49.180 --> 00:21:50.920 just in the ganglionic eminence. NOTE Confidence: 0.943838304444445 00:21:50.920 --> 00:21:53.760 And so ARX is normal in these NOTE Confidence: 0.943838304444445 00:21:53.760 --> 00:21:55.280 excitatory radially migrating cells, NOTE Confidence: 0.943838304444445 00:21:55.280 --> 00:21:57.120 but it's completely absent NOTE Confidence: 0.943838304444445 00:21:57.120 --> 00:21:58.960 from the ganglionic eminence. NOTE Confidence: 0.943838304444445 00:21:58.960 --> 00:22:00.600 And when we do that, NOTE Confidence: 0.943838304444445 00:22:00.600 --> 00:22:02.040 what we see and hopefully I'll NOTE Confidence: 0.943838304444445 00:22:02.040 --> 00:22:03.000 get this to work. NOTE Confidence: 0.905900966666667 00:22:06.440 --> 00:22:08.442 There we go. So on your left NOTE Confidence: 0.905900966666667 00:22:08.442 --> 00:22:10.360 side is a normal brain. NOTE Confidence: 0.905900966666667 00:22:10.360 --> 00:22:12.980 We've genetically labeled all the NOTE Confidence: 0.905900966666667 00:22:12.980 --> 00:22:15.684 inhibitory neurons with a green dye NOTE Confidence: 0.905900966666667 00:22:15.684 --> 00:22:17.798 GFP and you can see them migrating NOTE Confidence: 0.905900966666667 00:22:17.798 --> 00:22:19.602 out of the ganglionic eminence NOTE Confidence: 0.905900966666667 00:22:19.602 --> 00:22:21.756 up towards the cortex and then NOTE Confidence: 0.905900966666667 00:22:21.819 --> 00:22:23.955 turning and going into the cortex. NOTE Confidence: 0.905900966666667 00:22:23.960 --> 00:22:26.198 Now what happens in the mutant NOTE Confidence: 0.905900966666667 00:22:26.200 --> 00:22:27.016 is that these cells, NOTE Confidence: 0.905900966666667 00:22:27.016 --> 00:22:28.240 you don't see quite the connection, NOTE Confidence: 0.905900966666667 00:22:28.240 --> 00:22:29.864 but they're migrating out NOTE Confidence: 0.905900966666667 00:22:29.864 --> 00:22:31.520 of the ganglionic eminence, NOTE Confidence: 0.905900966666667 00:22:31.520 --> 00:22:34.040 they're going up into the cortex. NOTE Confidence: 0.905900966666667 00:22:34.040 --> 00:22:35.720 But I'm sorry going up door sleep, NOTE Confidence: 0.905900966666667 00:22:35.720 --> 00:22:37.834 but they don't turn out of their NOTE Confidence: 0.905900966666667 00:22:37.834 --> 00:22:40.119 stream and go out into the cortex. NOTE Confidence: 0.905900966666667 00:22:40.120 --> 00:22:41.518 And also I don't know how NOTE Confidence: 0.905900966666667 00:22:41.518 --> 00:22:42.680 well you can see it, NOTE Confidence: 0.905900966666667 00:22:42.680 --> 00:22:44.175 but there's cells migrating out NOTE Confidence: 0.905900966666667 00:22:44.175 --> 00:22:46.382 here in the marginal zone and those NOTE Confidence: 0.905900966666667 00:22:46.382 --> 00:22:48.626 are completely absent from the ARX. NOTE Confidence: 0.905900966666667 00:22:48.626 --> 00:22:50.736 So it's completely eliminated one NOTE Confidence: 0.905900966666667 00:22:50.736 --> 00:22:52.923 stream of these inhibitory neurons NOTE Confidence: 0.905900966666667 00:22:52.923 --> 00:22:55.877 and it's there's a defect in the NOTE Confidence: 0.905900966666667 00:22:55.953 --> 00:22:58.248 migration of that other stream. NOTE Confidence: 0.905900966666667 00:22:58.250 --> 00:22:59.810 Now when we study these mice, NOTE Confidence: 0.905900966666667 00:22:59.810 --> 00:23:01.142 I can tell you the brain NOTE Confidence: 0.905900966666667 00:23:01.142 --> 00:23:01.808 is structurally normal. NOTE Confidence: 0.905900966666667 00:23:01.810 --> 00:23:02.770 This has all been published, NOTE Confidence: 0.905900966666667 00:23:02.770 --> 00:23:04.450 so I'm not going to go through details. NOTE Confidence: 0.905900966666667 00:23:04.450 --> 00:23:05.970 The brain is structurally normal. NOTE Confidence: 0.905900966666667 00:23:05.970 --> 00:23:08.410 The corpus callosum is intact. NOTE Confidence: 0.905900966666667 00:23:08.410 --> 00:23:11.090 The cell layers are intact. NOTE Confidence: 0.905900966666667 00:23:11.090 --> 00:23:13.337 Every single one of these mice that NOTE Confidence: 0.905900966666667 00:23:13.337 --> 00:23:15.262 we've tested has epilepsy from the NOTE Confidence: 0.905900966666667 00:23:15.262 --> 00:23:17.590 very first time we can look at it. NOTE Confidence: 0.905900966666667 00:23:17.590 --> 00:23:20.026 So they develop different types of epilepsy. NOTE Confidence: 0.905900966666667 00:23:20.030 --> 00:23:22.284 We see these spikes and slow wave NOTE Confidence: 0.905900966666667 00:23:22.284 --> 00:23:24.004 with an electrical decrement like NOTE Confidence: 0.905900966666667 00:23:24.004 --> 00:23:26.426 here that's what you see in children NOTE Confidence: 0.905900966666667 00:23:26.426 --> 00:23:28.390 with infantile spasm syndrome, NOTE Confidence: 0.905900966666667 00:23:28.390 --> 00:23:30.946 exactly like what you see with NOTE Confidence: 0.905900966666667 00:23:30.946 --> 00:23:32.224 the ARX mutations. NOTE Confidence: 0.905900966666667 00:23:32.230 --> 00:23:34.105 These are these Jacksonian type NOTE Confidence: 0.905900966666667 00:23:34.105 --> 00:23:35.980 seizures which start and then NOTE Confidence: 0.905900966666667 00:23:36.043 --> 00:23:37.947 propagate throughout the brain. NOTE Confidence: 0.905900966666667 00:23:37.950 --> 00:23:40.771 So we see an evolution and different NOTE Confidence: 0.905900966666667 00:23:40.771 --> 00:23:43.029 types of seizures starting from NOTE Confidence: 0.905900966666667 00:23:43.030 --> 00:23:45.424 the earliest time we can record it. NOTE Confidence: 0.905900966666667 00:23:45.430 --> 00:23:47.998 So these mice all have seizures. NOTE Confidence: 0.905900966666667 00:23:48.000 --> 00:23:51.280 And the brains, as I said, NOTE Confidence: 0.905900966666667 00:23:51.280 --> 00:23:53.560 are completely normal. NOTE Confidence: 0.905900966666667 00:23:53.560 --> 00:23:57.360 Now in contrast, if we remove a RX, NOTE Confidence: 0.905900966666667 00:23:57.360 --> 00:23:59.760 instead of from the ganglionic Eminence, NOTE Confidence: 0.905900966666667 00:23:59.760 --> 00:24:02.370 we remove it from the excited where NOTE Confidence: 0.905900966666667 00:24:02.370 --> 00:24:04.595 the excitatory neurons are being NOTE Confidence: 0.905900966666667 00:24:04.595 --> 00:24:07.320 derived using a different Cree driver, NOTE Confidence: 0.905900966666667 00:24:07.320 --> 00:24:09.540 what we see is something NOTE Confidence: 0.905900966666667 00:24:09.540 --> 00:24:10.428 completely different. NOTE Confidence: 0.905900966666667 00:24:10.430 --> 00:24:12.182 Now what you see is that NOTE Confidence: 0.905900966666667 00:24:12.182 --> 00:24:13.830 the the brains are small. NOTE Confidence: 0.905900966666667 00:24:13.830 --> 00:24:15.954 Remember I told you the brains NOTE Confidence: 0.905900966666667 00:24:15.954 --> 00:24:17.830 are structurally normal with the NOTE Confidence: 0.905900966666667 00:24:17.830 --> 00:24:19.830 removal from the inhibitory neurons. NOTE Confidence: 0.905900966666667 00:24:19.830 --> 00:24:21.390 The cortex is very thin, NOTE Confidence: 0.905900966666667 00:24:21.390 --> 00:24:23.202 it's actually dislaminated and NOTE Confidence: 0.905900966666667 00:24:23.202 --> 00:24:25.467 you have no corpus callosum. NOTE Confidence: 0.905900966666667 00:24:25.470 --> 00:24:27.507 So here you can see a normal NOTE Confidence: 0.905900966666667 00:24:27.507 --> 00:24:29.396 corpus callosum and here you see NOTE Confidence: 0.905900966666667 00:24:29.396 --> 00:24:30.986 a genesis of corpus callosum. NOTE Confidence: 0.905900966666667 00:24:30.990 --> 00:24:33.792 So by removing it from the NOTE Confidence: 0.905900966666667 00:24:33.792 --> 00:24:35.660 excitatory projection neurons you NOTE Confidence: 0.905900966666667 00:24:35.737 --> 00:24:38.147 get all the structural defects. NOTE Confidence: 0.905900966666667 00:24:38.150 --> 00:24:40.229 That you get none of the epilepsy. NOTE Confidence: 0.905900966666667 00:24:40.230 --> 00:24:41.586 We've looked at hundreds of mice. NOTE Confidence: 0.905900966666667 00:24:41.590 --> 00:24:44.350 We've never seen a seizure. NOTE Confidence: 0.905900966666667 00:24:44.350 --> 00:24:46.460 So now we're starting to NOTE Confidence: 0.905900966666667 00:24:46.460 --> 00:24:48.483 distinguish where does the kind NOTE Confidence: 0.905900966666667 00:24:48.483 --> 00:24:50.148 of cognitive behavioral and where NOTE Confidence: 0.905900966666667 00:24:50.148 --> 00:24:52.460 do some of the other neurologic NOTE Confidence: 0.905900966666667 00:24:52.460 --> 00:24:54.750 phenotypes where they derive from, NOTE Confidence: 0.905900966666667 00:24:54.750 --> 00:24:56.425 from a cell migration standpoint NOTE Confidence: 0.905900966666667 00:24:56.425 --> 00:24:58.100 and and this just shows. NOTE Confidence: 0.905900966666667 00:24:58.100 --> 00:25:00.020 The disruption of the cortical lamination, NOTE Confidence: 0.905900966666667 00:25:00.020 --> 00:25:03.188 we can look at at specific genes that NOTE Confidence: 0.905900966666667 00:25:03.188 --> 00:25:05.561 are expressed in specific laminate NOTE Confidence: 0.905900966666667 00:25:05.561 --> 00:25:07.553 and show defects predominantly NOTE Confidence: 0.905900966666667 00:25:07.553 --> 00:25:10.060 in the upper layer cells. NOTE Confidence: 0.905900966666667 00:25:10.060 --> 00:25:12.300 And those upper layer cells in the NOTE Confidence: 0.9553487 00:25:12.300 --> 00:25:14.500 mouse come from those intermediate NOTE Confidence: 0.9553487 00:25:14.500 --> 00:25:16.700 progenitor cells that I mentioned. NOTE Confidence: 0.9553487 00:25:16.700 --> 00:25:18.940 And so we looked at those intermediate NOTE Confidence: 0.9553487 00:25:18.940 --> 00:25:20.660 progenitor cells and what we found NOTE Confidence: 0.9553487 00:25:20.660 --> 00:25:23.516 doing single cell is that they are NOTE Confidence: 0.9553487 00:25:23.516 --> 00:25:26.600 missing something called CDKN 1C. NOTE Confidence: 0.9553487 00:25:26.600 --> 00:25:29.720 ARX is regulating CDKN 1C, NOTE Confidence: 0.9553487 00:25:29.720 --> 00:25:31.484 and that's a gene that's important for NOTE Confidence: 0.9553487 00:25:31.484 --> 00:25:33.478 cells being able to reenter the cell cycle. NOTE Confidence: 0.9553487 00:25:33.480 --> 00:25:35.358 So what's happening is these cells, NOTE Confidence: 0.9553487 00:25:35.360 --> 00:25:38.940 because they no longer express the CDKN 1C, NOTE Confidence: 0.9553487 00:25:38.940 --> 00:25:42.000 are exiting the cell cycle prematurely. NOTE Confidence: 0.9553487 00:25:42.000 --> 00:25:44.525 Therefore you're not getting the NOTE Confidence: 0.9553487 00:25:44.525 --> 00:25:47.640 correct number of of rounds of mitosis NOTE Confidence: 0.9553487 00:25:47.640 --> 00:25:49.240 in the intermediate progenitor NOTE Confidence: 0.9553487 00:25:49.240 --> 00:25:51.972 cell and you've got a defect in NOTE Confidence: 0.9553487 00:25:51.972 --> 00:25:53.837 those mostly upper layer neurons. NOTE Confidence: 0.934383218333333 00:25:55.900 --> 00:25:59.284 We can actually test that by going in NOTE Confidence: 0.934383218333333 00:25:59.284 --> 00:26:02.740 and we built a a system to actually NOTE Confidence: 0.934383218333333 00:26:02.740 --> 00:26:04.580 repress actually what happened. NOTE Confidence: 0.934383218333333 00:26:04.580 --> 00:26:05.840 Sorry, I just misspoke. NOTE Confidence: 0.934383218333333 00:26:05.840 --> 00:26:07.988 There's over expression of the CDKN 1C. NOTE Confidence: 0.934383218333333 00:26:07.988 --> 00:26:09.976 The ARX is a repressor of that. NOTE Confidence: 0.934383218333333 00:26:09.980 --> 00:26:12.689 We then knocked it down and we can see NOTE Confidence: 0.934383218333333 00:26:12.689 --> 00:26:15.603 the return of the proliferation and we NOTE Confidence: 0.934383218333333 00:26:15.603 --> 00:26:18.301 actually can rescue that phenotype of NOTE Confidence: 0.934383218333333 00:26:18.301 --> 00:26:21.097 loss of the mostly superficial neurons. NOTE Confidence: 0.934383218333333 00:26:21.100 --> 00:26:23.746 So this showed that that was one of the NOTE Confidence: 0.934383218333333 00:26:23.746 --> 00:26:25.618 mechanisms by which ARX was functioning. NOTE Confidence: 0.931867333333333 00:26:28.470 --> 00:26:31.068 So with this all in mind, NOTE Confidence: 0.931867333333333 00:26:31.070 --> 00:26:32.840 I want to turn our attention NOTE Confidence: 0.931867333333333 00:26:32.840 --> 00:26:34.890 to this set of two kids. NOTE Confidence: 0.931867333333333 00:26:34.890 --> 00:26:37.692 Now at the top is a child NOTE Confidence: 0.931867333333333 00:26:37.692 --> 00:26:40.227 who has an ARX mutation. NOTE Confidence: 0.931867333333333 00:26:40.230 --> 00:26:43.052 And that mutation, that child has had NOTE Confidence: 0.931867333333333 00:26:43.052 --> 00:26:45.344 epilepsy starting at about six months NOTE Confidence: 0.931867333333333 00:26:45.350 --> 00:26:47.374 in severe intellectual disabilities, NOTE Confidence: 0.931867333333333 00:26:47.374 --> 00:26:50.410 never was able to feed himself. NOTE Confidence: 0.931867333333333 00:26:50.410 --> 00:26:52.545 And you can see has the so-called NOTE Confidence: 0.931867333333333 00:26:52.545 --> 00:26:54.185 lizencephaly, the smooth brain NOTE Confidence: 0.931867333333333 00:26:54.185 --> 00:26:55.965 Lysos meaning smooth encephaly, NOTE Confidence: 0.931867333333333 00:26:55.970 --> 00:26:57.048 brain lizencephaly. NOTE Confidence: 0.931867333333333 00:26:57.048 --> 00:26:59.743 And you can see predominantly NOTE Confidence: 0.931867333333333 00:26:59.743 --> 00:27:01.850 in this posterior part. NOTE Confidence: 0.931867333333333 00:27:01.850 --> 00:27:04.886 There's no suicide here at all. NOTE Confidence: 0.931867333333333 00:27:04.890 --> 00:27:06.770 Here you can see posteriorly. NOTE Confidence: 0.931867333333333 00:27:06.770 --> 00:27:09.962 Now the child at the bottom also has NOTE Confidence: 0.931867333333333 00:27:09.962 --> 00:27:12.971 an ARX mutation, also had epilepsy. NOTE Confidence: 0.931867333333333 00:27:12.971 --> 00:27:16.839 It didn't start till about 9 to 10 months NOTE Confidence: 0.931867333333333 00:27:16.839 --> 00:27:19.544 and had severe intellectual disability. NOTE Confidence: 0.931867333333333 00:27:19.550 --> 00:27:23.906 But this brain is structurally normal. NOTE Confidence: 0.931867333333333 00:27:23.910 --> 00:27:27.213 The brain of the child at the top had NOTE Confidence: 0.931867333333333 00:27:27.213 --> 00:27:30.938 a truncation mutation loss of a RX. NOTE Confidence: 0.931867333333333 00:27:30.938 --> 00:27:33.885 The child at the bottom had an NOTE Confidence: 0.931867333333333 00:27:33.885 --> 00:27:36.469 alanine tract expansion mutation. NOTE Confidence: 0.931867333333333 00:27:36.470 --> 00:27:39.470 Now if we think about what I just told you, NOTE Confidence: 0.931867333333333 00:27:39.470 --> 00:27:41.110 the brain is structurally normal, NOTE Confidence: 0.931867333333333 00:27:41.110 --> 00:27:44.142 but you have the seizures if you have NOTE Confidence: 0.931867333333333 00:27:44.142 --> 00:27:47.208 a defect in your inhibitory neurons. NOTE Confidence: 0.931867333333333 00:27:47.210 --> 00:27:48.218 But it's only when you have NOTE Confidence: 0.931867333333333 00:27:48.218 --> 00:27:49.330 a defect in the migration, NOTE Confidence: 0.931867333333333 00:27:49.330 --> 00:27:52.048 the movement of those excitatory neurons NOTE Confidence: 0.931867333333333 00:27:52.050 --> 00:27:54.888 that you have the structural defects. NOTE Confidence: 0.931867333333333 00:27:54.890 --> 00:27:56.546 So we predicted that that's what NOTE Confidence: 0.931867333333333 00:27:56.546 --> 00:27:58.568 we would see if we tested this. NOTE Confidence: 0.931867333333333 00:27:58.570 --> 00:28:02.170 So that's what we did experimentally. NOTE Confidence: 0.931867333333333 00:28:02.170 --> 00:28:03.650 So to do these experiments, NOTE Confidence: 0.931867333333333 00:28:03.650 --> 00:28:05.369 we went in and and you can do something NOTE Confidence: 0.931867333333333 00:28:05.369 --> 00:28:06.608 called in utero electropration. NOTE Confidence: 0.931867333333333 00:28:06.610 --> 00:28:09.290 This is where you can take a mouse, NOTE Confidence: 0.931867333333333 00:28:09.290 --> 00:28:10.658 a gravid mom, NOTE Confidence: 0.931867333333333 00:28:10.658 --> 00:28:12.938 you can exteriorize the uterus. NOTE Confidence: 0.931867333333333 00:28:12.940 --> 00:28:15.664 You can go in and check some of NOTE Confidence: 0.931867333333333 00:28:15.664 --> 00:28:17.884 an expression construct into the NOTE Confidence: 0.931867333333333 00:28:17.884 --> 00:28:20.264 ventricle of the into the pup while NOTE Confidence: 0.931867333333333 00:28:20.264 --> 00:28:22.238 it's in the uterus and you put NOTE Confidence: 0.931867333333333 00:28:22.238 --> 00:28:23.978 these electrodes on either side, NOTE Confidence: 0.931867333333333 00:28:23.980 --> 00:28:25.200 you electroplate it just like NOTE Confidence: 0.931867333333333 00:28:25.200 --> 00:28:26.420 you would in a gel. NOTE Confidence: 0.931867333333333 00:28:26.420 --> 00:28:29.276 The DNA goes into the brain and then NOTE Confidence: 0.931867333333333 00:28:29.276 --> 00:28:32.275 you can actually return the grab the NOTE Confidence: 0.931867333333333 00:28:32.275 --> 00:28:34.060 uterus back into the mom sewer up NOTE Confidence: 0.931867333333333 00:28:34.060 --> 00:28:36.334 and those mice can go on and even be NOTE Confidence: 0.931867333333333 00:28:36.334 --> 00:28:38.578 delivered so we can study them later NOTE Confidence: 0.931867333333333 00:28:38.580 --> 00:28:41.650 and what you see is if you do that normally. NOTE Confidence: 0.931867333333333 00:28:41.650 --> 00:28:43.526 The cells migrate out to the cortex. NOTE Confidence: 0.931867333333333 00:28:43.530 --> 00:28:46.078 So this is just with the GFP NOTE Confidence: 0.931867333333333 00:28:46.078 --> 00:28:48.248 electroprated into our ARX Flox mice, NOTE Confidence: 0.931867333333333 00:28:48.250 --> 00:28:49.278 no Cree. NOTE Confidence: 0.931867333333333 00:28:49.278 --> 00:28:51.848 So they're just wild type. NOTE Confidence: 0.931867333333333 00:28:51.850 --> 00:28:54.025 If we introduce a brain NOTE Confidence: 0.931867333333333 00:28:54.025 --> 00:28:56.674 four or this how 3F4 Cree. NOTE Confidence: 0.931867333333333 00:28:56.674 --> 00:29:00.250 What you see when you electroprate in GFP, NOTE Confidence: 0.931867333333333 00:29:00.250 --> 00:29:02.567 now they've lost all of their ARX. NOTE Confidence: 0.931867333333333 00:29:02.570 --> 00:29:05.727 You see that these cells don't migrate. NOTE Confidence: 0.931867333333333 00:29:05.730 --> 00:29:08.484 If we rescue this with a wild type ARX, NOTE Confidence: 0.931867333333333 00:29:08.490 --> 00:29:10.488 you see the cells migrate out to the surface, NOTE Confidence: 0.931867333333333 00:29:10.490 --> 00:29:11.930 just not very nicely. NOTE Confidence: 0.931867333333333 00:29:11.930 --> 00:29:14.090 You have a very nice rescue. NOTE Confidence: 0.931867333333333 00:29:14.090 --> 00:29:16.570 But if you do that with the sorry, NOTE Confidence: 0.931867333333333 00:29:16.570 --> 00:29:18.723 and if you do that with the ARX NOTE Confidence: 0.931867333333333 00:29:18.723 --> 00:29:21.088 that has that expansion mutation, NOTE Confidence: 0.931867333333333 00:29:21.090 --> 00:29:23.286 you also rescue that radial migration. NOTE Confidence: 0.931867333333333 00:29:23.290 --> 00:29:25.649 These cells migrate out to the surface. NOTE Confidence: 0.931867333333333 00:29:25.650 --> 00:29:27.990 So the expansion mutation doesn't seem NOTE Confidence: 0.931867333333333 00:29:27.990 --> 00:29:30.090 to affect these excitatory neurons, NOTE Confidence: 0.931867333333333 00:29:30.090 --> 00:29:31.805 at least their ability to migrate out. NOTE Confidence: 0.95175457 00:29:35.660 --> 00:29:38.138 Now contrast that to the inhibitory neurons. NOTE Confidence: 0.95175457 00:29:38.140 --> 00:29:40.534 So now what we've done is when you put NOTE Confidence: 0.95175457 00:29:40.534 --> 00:29:42.724 it in the wild type, the cells migrate NOTE Confidence: 0.95175457 00:29:42.724 --> 00:29:44.460 out very nicely up into the cortex. NOTE Confidence: 0.95175457 00:29:44.460 --> 00:29:46.480 So now we've just electroplate NOTE Confidence: 0.95175457 00:29:46.480 --> 00:29:48.096 into the ganglionic eminence. NOTE Confidence: 0.95175457 00:29:48.100 --> 00:29:50.494 The cells migrate up when you put it in, NOTE Confidence: 0.95175457 00:29:50.500 --> 00:29:53.056 when you remove a RX from the whole brain, NOTE Confidence: 0.95175457 00:29:53.060 --> 00:29:54.190 you see that these cells NOTE Confidence: 0.95175457 00:29:54.190 --> 00:29:55.094 no longer migrate up. NOTE Confidence: 0.95175457 00:29:55.100 --> 00:29:57.396 They kind of get stuck down here NOTE Confidence: 0.95175457 00:29:57.396 --> 00:29:59.620 in what will become striatum. NOTE Confidence: 0.95175457 00:29:59.620 --> 00:30:02.300 If we rescue with the wild type ARX, NOTE Confidence: 0.95175457 00:30:02.300 --> 00:30:04.246 you can see that again these cells NOTE Confidence: 0.95175457 00:30:04.246 --> 00:30:05.800 are migrating up very nicely. NOTE Confidence: 0.95175457 00:30:05.800 --> 00:30:07.560 Yeah, you can see that. NOTE Confidence: 0.95175457 00:30:07.560 --> 00:30:09.310 But if we do that with the NOTE Confidence: 0.95175457 00:30:09.310 --> 00:30:10.560 alanine tract expansion mutation, NOTE Confidence: 0.95175457 00:30:10.560 --> 00:30:12.800 they don't. NOTE Confidence: 0.95175457 00:30:12.800 --> 00:30:16.106 So the alanine tract expansion seems NOTE Confidence: 0.95175457 00:30:16.106 --> 00:30:18.740 to be differentially affecting NOTE Confidence: 0.95175457 00:30:18.740 --> 00:30:22.625 the inhibitory neurons and a whole NOTE Confidence: 0.95175457 00:30:22.625 --> 00:30:24.515 series of experiments that we did, NOTE Confidence: 0.95175457 00:30:24.520 --> 00:30:27.810 we went on to show that it was due to NOTE Confidence: 0.95175457 00:30:27.906 --> 00:30:31.466 the ability of a RX and Progenitor cells NOTE Confidence: 0.95175457 00:30:31.466 --> 00:30:35.568 to affect different transcriptional pathways. NOTE Confidence: 0.95175457 00:30:35.570 --> 00:30:37.610 So in the inhibitory neurons, NOTE Confidence: 0.95175457 00:30:37.610 --> 00:30:39.165 what happens when you have NOTE Confidence: 0.95175457 00:30:39.165 --> 00:30:40.409 an alanine tract expansion? NOTE Confidence: 0.95175457 00:30:40.410 --> 00:30:41.730 Remember transcription isn't NOTE Confidence: 0.95175457 00:30:41.730 --> 00:30:43.930 isolated to 1 transcription factor, NOTE Confidence: 0.95175457 00:30:43.930 --> 00:30:46.030 it's a transcriptional complex usually NOTE Confidence: 0.95175457 00:30:46.030 --> 00:30:48.810 with 40 to 60 different proteins. NOTE Confidence: 0.95175457 00:30:48.810 --> 00:30:51.230 And so this complex usually NOTE Confidence: 0.95175457 00:30:51.230 --> 00:30:53.166 has stabilizers and cofactors. NOTE Confidence: 0.95175457 00:30:53.170 --> 00:30:56.176 And what happens in the we showed NOTE Confidence: 0.95175457 00:30:56.176 --> 00:30:57.754 through Co immunoprecipitation. NOTE Confidence: 0.95175457 00:30:57.754 --> 00:31:01.905 This complex falls apart and this T LE1 NOTE Confidence: 0.95175457 00:31:01.905 --> 00:31:04.665 which is a gaucho like transcriptional NOTE Confidence: 0.95175457 00:31:04.665 --> 00:31:06.575 repressor involved in repressing NOTE Confidence: 0.95175457 00:31:06.575 --> 00:31:10.112 things like Ed F3 and also that CDKN NOTE Confidence: 0.95175457 00:31:10.112 --> 00:31:13.808 1C that I mentioned no longer get repressed. NOTE Confidence: 0.95175457 00:31:13.810 --> 00:31:16.302 They continue to be overexpressed and that NOTE Confidence: 0.95175457 00:31:16.302 --> 00:31:19.010 leads to defects in these inhibitory norms. NOTE Confidence: 0.95175457 00:31:19.010 --> 00:31:19.661 However, NOTE Confidence: 0.95175457 00:31:19.661 --> 00:31:21.614 the transcriptional complex NOTE Confidence: 0.95175457 00:31:21.614 --> 00:31:23.567 is structurally different. NOTE Confidence: 0.95175457 00:31:23.570 --> 00:31:25.235 In the excitatory neurons such NOTE Confidence: 0.95175457 00:31:25.235 --> 00:31:27.339 that even with that polyne alanine NOTE Confidence: 0.95175457 00:31:27.339 --> 00:31:29.583 tract expansion that leads to a NOTE Confidence: 0.95175457 00:31:29.583 --> 00:31:31.529 conformational change in this protein, NOTE Confidence: 0.95175457 00:31:31.530 --> 00:31:34.890 you still get the structure of this, NOTE Confidence: 0.95175457 00:31:34.890 --> 00:31:37.285 the cofactors coming together and NOTE Confidence: 0.95175457 00:31:37.285 --> 00:31:39.680 it still can repress molecules NOTE Confidence: 0.95175457 00:31:39.758 --> 00:31:42.740 like LMO one which are required for NOTE Confidence: 0.95175457 00:31:42.740 --> 00:31:44.850 the excitatory neuron migration. NOTE Confidence: 0.95175457 00:31:44.850 --> 00:31:47.433 And so this shows how this one NOTE Confidence: 0.95175457 00:31:47.433 --> 00:31:49.034 transcription factor with a NOTE Confidence: 0.95175457 00:31:49.034 --> 00:31:51.174 single mutation can have different NOTE Confidence: 0.95175457 00:31:51.174 --> 00:31:52.886 functions in different cell, NOTE Confidence: 0.95175457 00:31:52.890 --> 00:31:54.810 in different progenitor cells NOTE Confidence: 0.95175457 00:31:54.810 --> 00:31:56.730 leading to different phenotypes. NOTE Confidence: 0.95175457 00:31:56.730 --> 00:31:59.778 Whereas in in if you remove a RX NOTE Confidence: 0.95175457 00:31:59.778 --> 00:32:02.410 it'll affect both of them together NOTE Confidence: 0.95175457 00:32:02.410 --> 00:32:04.695 and that's what happens with NOTE Confidence: 0.95175457 00:32:04.695 --> 00:32:06.523 the Liz encephaly phenotype. NOTE Confidence: 0.95175457 00:32:06.530 --> 00:32:10.592 Now we went on to take a non NOTE Confidence: 0.95175457 00:32:10.592 --> 00:32:13.147 unbiased proteomics approach to say. NOTE Confidence: 0.95175457 00:32:13.150 --> 00:32:14.190 Wow, this is really interesting. NOTE Confidence: 0.95175457 00:32:14.190 --> 00:32:15.370 What are all the proteins NOTE Confidence: 0.95175457 00:32:15.370 --> 00:32:16.550 that interact with a RX? NOTE Confidence: 0.95175457 00:32:16.550 --> 00:32:19.287 Because we want to understand that whole NOTE Confidence: 0.95175457 00:32:19.287 --> 00:32:21.108 transcriptional complex and we actually NOTE Confidence: 0.95175457 00:32:21.108 --> 00:32:23.184 uncovered a number of different proteins. NOTE Confidence: 0.95175457 00:32:23.190 --> 00:32:25.845 But unfortunately we were really NOTE Confidence: 0.95175457 00:32:25.845 --> 00:32:27.801 looking for other transcription factors NOTE Confidence: 0.95175457 00:32:27.801 --> 00:32:29.583 that are interacting with a RX, NOTE Confidence: 0.95175457 00:32:29.590 --> 00:32:30.654 and I'm going to come back to NOTE Confidence: 0.95175457 00:32:30.654 --> 00:32:31.430 that in a minute. NOTE Confidence: 0.95175457 00:32:31.430 --> 00:32:33.201 What we did find is a number NOTE Confidence: 0.95175457 00:32:33.201 --> 00:32:34.868 of things that are involved in NOTE Confidence: 0.95175457 00:32:34.868 --> 00:32:36.434 the when signaling pathway, NOTE Confidence: 0.95175457 00:32:36.434 --> 00:32:38.574 which is important for proliferation NOTE Confidence: 0.95175457 00:32:38.574 --> 00:32:40.492 in those cortical ventricular cells. NOTE Confidence: 0.95175457 00:32:40.492 --> 00:32:42.970 So I'm not going to that's that's NOTE Confidence: 0.95175457 00:32:43.034 --> 00:32:44.078 work we published. NOTE Confidence: 0.95175457 00:32:44.080 --> 00:32:45.800 I'm not going to talk about it today. NOTE Confidence: 0.95175457 00:32:45.800 --> 00:32:49.363 But we also found that it affected NOTE Confidence: 0.95175457 00:32:49.363 --> 00:32:52.078 dorsal ventral patterning in the brain. NOTE Confidence: 0.935608953846154 00:32:52.080 --> 00:32:55.491 So if you take the brain and this is NOTE Confidence: 0.935608953846154 00:32:55.491 --> 00:32:57.651 expression of Olig 2, some work we NOTE Confidence: 0.935608953846154 00:32:57.651 --> 00:32:59.818 published just a few years ago here NOTE Confidence: 0.935608953846154 00:32:59.818 --> 00:33:03.220 you can see a very nice border where a NOTE Confidence: 0.935608953846154 00:33:03.314 --> 00:33:06.658 RX is normally sorry where all Olig 2. NOTE Confidence: 0.935608953846154 00:33:06.660 --> 00:33:08.796 Stops being expressed, and you can NOTE Confidence: 0.935608953846154 00:33:08.796 --> 00:33:11.236 see that here in the coronal plane. NOTE Confidence: 0.935608953846154 00:33:11.236 --> 00:33:14.896 And if you look at it in the sagittal plane, NOTE Confidence: 0.935608953846154 00:33:14.896 --> 00:33:18.528 you can see that it stops at the top of NOTE Confidence: 0.935608953846154 00:33:18.528 --> 00:33:21.336 that gang, that lateral ganglionic eminence. NOTE Confidence: 0.935608953846154 00:33:21.340 --> 00:33:23.500 But that's not what happens NOTE Confidence: 0.935608953846154 00:33:23.500 --> 00:33:24.856 in the ARX mutant. NOTE Confidence: 0.935608953846154 00:33:24.856 --> 00:33:27.260 You can see that this olive two, NOTE Confidence: 0.935608953846154 00:33:27.260 --> 00:33:29.160 normally only expressed in the NOTE Confidence: 0.935608953846154 00:33:29.160 --> 00:33:31.060 ventral part of the brain, NOTE Confidence: 0.935608953846154 00:33:31.060 --> 00:33:33.168 is now expressed extensively NOTE Confidence: 0.935608953846154 00:33:33.168 --> 00:33:35.276 across the dorsal cortex. NOTE Confidence: 0.935608953846154 00:33:35.280 --> 00:33:37.872 And you can see it going up beyond where NOTE Confidence: 0.935608953846154 00:33:37.872 --> 00:33:41.216 we would normally see it in the wild type. NOTE Confidence: 0.935608953846154 00:33:41.216 --> 00:33:43.580 So this suggested that in addition NOTE Confidence: 0.935608953846154 00:33:43.665 --> 00:33:45.637 to a proliferation effect, NOTE Confidence: 0.935608953846154 00:33:45.640 --> 00:33:48.797 it was affecting patterning of the brain. NOTE Confidence: 0.935608953846154 00:33:48.800 --> 00:33:51.880 So what's important about that? NOTE Confidence: 0.935608953846154 00:33:51.880 --> 00:33:53.736 Oh, so we went on and showed that NOTE Confidence: 0.935608953846154 00:33:53.736 --> 00:33:55.478 it's not just the wind pathway, NOTE Confidence: 0.935608953846154 00:33:55.480 --> 00:33:56.892 but it's also FGFA. NOTE Confidence: 0.935608953846154 00:33:56.892 --> 00:33:59.010 And Sonic Hedgehog and we basically NOTE Confidence: 0.935608953846154 00:33:59.081 --> 00:34:01.419 were able to separate out all these NOTE Confidence: 0.935608953846154 00:34:01.419 --> 00:34:03.689 pathways and how that was affecting NOTE Confidence: 0.935608953846154 00:34:03.689 --> 00:34:06.089 all of two and downstream components. NOTE Confidence: 0.935608953846154 00:34:06.090 --> 00:34:06.316 Again, NOTE Confidence: 0.935608953846154 00:34:06.316 --> 00:34:08.124 these are not things I'm going to talk NOTE Confidence: 0.935608953846154 00:34:08.124 --> 00:34:09.730 about today in the interest of time. NOTE Confidence: 0.935608953846154 00:34:09.730 --> 00:34:11.146 But what we, NOTE Confidence: 0.935608953846154 00:34:11.146 --> 00:34:13.506 the reason we became interested NOTE Confidence: 0.935608953846154 00:34:13.506 --> 00:34:16.448 in this patterning is because NOTE Confidence: 0.935608953846154 00:34:16.450 --> 00:34:19.467 these mice as I've alluded to have NOTE Confidence: 0.935608953846154 00:34:19.467 --> 00:34:21.452 behavioral defects and we wanted NOTE Confidence: 0.935608953846154 00:34:21.452 --> 00:34:23.322 to understand what's the biologic NOTE Confidence: 0.935608953846154 00:34:23.322 --> 00:34:25.820 basis of these behavioral defects. NOTE Confidence: 0.935608953846154 00:34:25.820 --> 00:34:28.412 So it turns out that and again some studies NOTE Confidence: 0.935608953846154 00:34:28.412 --> 00:34:30.891 we did a few years ago back in 2014, NOTE Confidence: 0.935608953846154 00:34:30.891 --> 00:34:33.046 we showed that these mice NOTE Confidence: 0.935608953846154 00:34:33.046 --> 00:34:34.339 have normal strength. NOTE Confidence: 0.935608953846154 00:34:34.340 --> 00:34:36.060 We had they have a lot of they, NOTE Confidence: 0.935608953846154 00:34:36.060 --> 00:34:38.970 they have normal ability to recognize NOTE Confidence: 0.935608953846154 00:34:38.970 --> 00:34:41.450 things in a remember things in a swim NOTE Confidence: 0.935608953846154 00:34:41.450 --> 00:34:43.615 test when you do Morris water maze. NOTE Confidence: 0.935608953846154 00:34:43.620 --> 00:34:45.540 But they're socially abnormal. NOTE Confidence: 0.935608953846154 00:34:45.540 --> 00:34:48.915 And this is typical of mice that are NOTE Confidence: 0.935608953846154 00:34:48.915 --> 00:34:51.340 believed to be in the human equivalent NOTE Confidence: 0.935608953846154 00:34:51.340 --> 00:34:53.340 of the autism spectrum disorder, NOTE Confidence: 0.935608953846154 00:34:53.340 --> 00:34:56.940 which as I said is part of the ARX phenotype. NOTE Confidence: 0.935608953846154 00:34:56.940 --> 00:34:58.796 And so here the I'm just going to NOTE Confidence: 0.935608953846154 00:34:58.796 --> 00:35:00.202 show you one socialization test NOTE Confidence: 0.935608953846154 00:35:00.202 --> 00:35:02.592 we did where you you take this is NOTE Confidence: 0.935608953846154 00:35:02.592 --> 00:35:04.004 called the novel mouse experiment NOTE Confidence: 0.935608953846154 00:35:04.004 --> 00:35:06.436 and where you what you do is you NOTE Confidence: 0.935608953846154 00:35:06.436 --> 00:35:08.709 put one mouse in this plexiglass NOTE Confidence: 0.935608953846154 00:35:08.709 --> 00:35:10.614 thing with these little holes. NOTE Confidence: 0.935608953846154 00:35:10.620 --> 00:35:12.223 And you put in the other side NOTE Confidence: 0.935608953846154 00:35:12.223 --> 00:35:14.069 of it and either an empty one NOTE Confidence: 0.935608953846154 00:35:14.069 --> 00:35:15.512 of these or an inanimate object, NOTE Confidence: 0.935608953846154 00:35:15.512 --> 00:35:17.123 you can put like a stuffed animal NOTE Confidence: 0.935608953846154 00:35:17.123 --> 00:35:18.497 or something like that in it. NOTE Confidence: 0.935608953846154 00:35:18.500 --> 00:35:20.460 And this is the test mouse right here. NOTE Confidence: 0.935608953846154 00:35:20.460 --> 00:35:23.020 And this mouse has never seen this mouse. NOTE Confidence: 0.935608953846154 00:35:23.020 --> 00:35:23.794 They're social creatures. NOTE Confidence: 0.935608953846154 00:35:23.794 --> 00:35:25.342 They're going to go and interact NOTE Confidence: 0.935608953846154 00:35:25.342 --> 00:35:26.100 with each other. NOTE Confidence: 0.935608953846154 00:35:26.100 --> 00:35:27.402 And you can see that when you NOTE Confidence: 0.935608953846154 00:35:27.402 --> 00:35:28.499 put in these novel mice, NOTE Confidence: 0.935608953846154 00:35:28.500 --> 00:35:31.380 the the blue bar shows you how much time, NOTE Confidence: 0.935608953846154 00:35:31.380 --> 00:35:33.865 the percent of time that they're spending NOTE Confidence: 0.935608953846154 00:35:33.865 --> 00:35:36.249 with that novel with that new mouse. NOTE Confidence: 0.935608953846154 00:35:36.250 --> 00:35:38.770 Whereas the mutants don't do that. NOTE Confidence: 0.935608953846154 00:35:38.770 --> 00:35:40.429 So they've got a socialization defect and NOTE Confidence: 0.935608953846154 00:35:40.429 --> 00:35:42.288 we showed that through several different, NOTE Confidence: 0.935608953846154 00:35:42.290 --> 00:35:45.450 but like I said this is just one of those. NOTE Confidence: 0.945285241666667 00:35:45.450 --> 00:35:47.808 So coming back to this patterning, NOTE Confidence: 0.945285241666667 00:35:47.810 --> 00:35:49.826 this was really interesting to us because NOTE Confidence: 0.945285241666667 00:35:49.826 --> 00:35:52.142 if you look at patterning dorsal ventral NOTE Confidence: 0.945285241666667 00:35:52.142 --> 00:35:54.629 patterning in the spinal cord where it's NOTE Confidence: 0.945285241666667 00:35:54.629 --> 00:35:58.082 been best elucidated work by Tom Jessel NOTE Confidence: 0.945285241666667 00:35:58.082 --> 00:36:01.696 and James Briscoe and others, many others. NOTE Confidence: 0.945285241666667 00:36:01.700 --> 00:36:04.148 What what we now know is that there's NOTE Confidence: 0.945285241666667 00:36:04.148 --> 00:36:06.784 specific cell types that come from different NOTE Confidence: 0.945285241666667 00:36:06.784 --> 00:36:08.739 regions along the progenitor zone, NOTE Confidence: 0.945285241666667 00:36:08.740 --> 00:36:11.340 from dorsal to ventral in the spinal cord, NOTE Confidence: 0.945285241666667 00:36:11.340 --> 00:36:15.076 and that these are defined by Sonic hedgehog NOTE Confidence: 0.945285241666667 00:36:15.076 --> 00:36:17.700 expressed out of the noto cord and then NOTE Confidence: 0.945285241666667 00:36:17.766 --> 00:36:20.259 in the floor plate and on the roof plate, NOTE Confidence: 0.945285241666667 00:36:20.260 --> 00:36:21.880 BMP's and wins, NOTE Confidence: 0.945285241666667 00:36:21.880 --> 00:36:25.633 and these both induce and repress. NOTE Confidence: 0.945285241666667 00:36:25.633 --> 00:36:27.766 Different transcription factors, NOTE Confidence: 0.945285241666667 00:36:27.770 --> 00:36:30.590 setting up these different domains NOTE Confidence: 0.945285241666667 00:36:30.590 --> 00:36:33.410 along the dorsal ventral axis. NOTE Confidence: 0.945285241666667 00:36:33.410 --> 00:36:36.186 And the same thing seems to be happening NOTE Confidence: 0.945285241666667 00:36:36.186 --> 00:36:38.650 in setting up different domains in NOTE Confidence: 0.945285241666667 00:36:38.650 --> 00:36:40.770 the cerebral cortex that define, NOTE Confidence: 0.945285241666667 00:36:40.770 --> 00:36:44.410 as I mentioned before, where the thalamic, NOTE Confidence: 0.945285241666667 00:36:44.410 --> 00:36:45.301 thalamic cortical projections NOTE Confidence: 0.945285241666667 00:36:45.301 --> 00:36:46.489 are going to be. NOTE Confidence: 0.945285241666667 00:36:46.490 --> 00:36:48.008 So you're getting your, you know, NOTE Confidence: 0.945285241666667 00:36:48.010 --> 00:36:49.662 visual cortex back here. NOTE Confidence: 0.945285241666667 00:36:49.662 --> 00:36:51.727 You get your motor cortex, NOTE Confidence: 0.945285241666667 00:36:51.730 --> 00:36:53.170 your sensory cortex. NOTE Confidence: 0.945285241666667 00:36:53.170 --> 00:36:55.570 All of these primary cortices NOTE Confidence: 0.945285241666667 00:36:55.570 --> 00:36:58.029 are coming out of definition, NOTE Confidence: 0.945285241666667 00:36:58.030 --> 00:37:00.046 and that definition starts NOTE Confidence: 0.945285241666667 00:37:00.046 --> 00:37:03.510 with these different gradients, NOTE Confidence: 0.945285241666667 00:37:03.510 --> 00:37:06.310 first identified by Denis O'Leary NOTE Confidence: 0.945285241666667 00:37:06.310 --> 00:37:07.990 and his group, NOTE Confidence: 0.945285241666667 00:37:07.990 --> 00:37:10.657 that you get a gradient of different NOTE Confidence: 0.945285241666667 00:37:10.657 --> 00:37:12.845 factors that turn on different NOTE Confidence: 0.945285241666667 00:37:12.845 --> 00:37:15.265 transcription factors in the brain, NOTE Confidence: 0.945285241666667 00:37:15.270 --> 00:37:18.721 and it's the overlap of these different NOTE Confidence: 0.945285241666667 00:37:18.721 --> 00:37:21.210 patterns of these signaling molecules. NOTE Confidence: 0.945285241666667 00:37:21.210 --> 00:37:23.710 Turning on transcription factors that NOTE Confidence: 0.945285241666667 00:37:23.710 --> 00:37:26.786 define these different regions of the brain, NOTE Confidence: 0.945285241666667 00:37:26.790 --> 00:37:27.023 well, NOTE Confidence: 0.945285241666667 00:37:27.023 --> 00:37:28.654 we had not actually been able to NOTE Confidence: 0.945285241666667 00:37:28.654 --> 00:37:30.270 find any transcription factors. NOTE Confidence: 0.945285241666667 00:37:30.270 --> 00:37:32.028 So we took a new approach, NOTE Confidence: 0.945285241666667 00:37:32.030 --> 00:37:33.682 something called Samoa which NOTE Confidence: 0.945285241666667 00:37:33.682 --> 00:37:35.747 stands for single molecule assay. NOTE Confidence: 0.945285241666667 00:37:35.750 --> 00:37:38.529 And this is a highly sensitive methodology NOTE Confidence: 0.945285241666667 00:37:38.529 --> 00:37:41.975 to be able to look at a single NOTE Confidence: 0.945285241666667 00:37:41.975 --> 00:37:44.150 molecules interacting with each other. NOTE Confidence: 0.945285241666667 00:37:44.150 --> 00:37:46.292 And we had to build a transcription NOTE Confidence: 0.945285241666667 00:37:46.292 --> 00:37:47.830 factor library because one didn't NOTE Confidence: 0.945285241666667 00:37:47.830 --> 00:37:49.225 exist for just the brains, NOTE Confidence: 0.945285241666667 00:37:49.230 --> 00:37:51.490 we took all we actually. NOTE Confidence: 0.945285241666667 00:37:51.490 --> 00:37:53.352 We cloned into a library all the NOTE Confidence: 0.945285241666667 00:37:53.352 --> 00:37:54.431 transcription factors that are NOTE Confidence: 0.945285241666667 00:37:54.431 --> 00:37:56.516 expressed in the brain and we then NOTE Confidence: 0.945285241666667 00:37:56.516 --> 00:37:58.808 asked which ones interact with ARX. NOTE Confidence: 0.945285241666667 00:37:58.810 --> 00:37:59.970 And when we did that NOTE Confidence: 0.946962533333333 00:38:02.410 --> 00:38:04.738 we were able to find a number of NOTE Confidence: 0.946962533333333 00:38:04.738 --> 00:38:06.690 different factor transcription factors. NOTE Confidence: 0.946962533333333 00:38:06.690 --> 00:38:08.334 Now that interacted with arx and NOTE Confidence: 0.946962533333333 00:38:08.334 --> 00:38:10.372 you can see they have overlapping NOTE Confidence: 0.946962533333333 00:38:10.372 --> 00:38:12.128 patterns in different regions, NOTE Confidence: 0.946962533333333 00:38:12.130 --> 00:38:14.650 so some just in the cortex, NOTE Confidence: 0.946962533333333 00:38:14.650 --> 00:38:17.536 others just in the ganglionic eminence. NOTE Confidence: 0.946962533333333 00:38:17.540 --> 00:38:18.914 And others that are both in NOTE Confidence: 0.946962533333333 00:38:18.914 --> 00:38:20.304 the cortex and the ganglionic NOTE Confidence: 0.946962533333333 00:38:20.304 --> 00:38:21.980 eminence in different patterns. NOTE Confidence: 0.946962533333333 00:38:21.980 --> 00:38:24.311 So this one just like ARX stronger NOTE Confidence: 0.946962533333333 00:38:24.311 --> 00:38:26.540 in the more posterior brain, NOTE Confidence: 0.946962533333333 00:38:26.540 --> 00:38:29.140 less so in the anterior. NOTE Confidence: 0.946962533333333 00:38:29.140 --> 00:38:31.820 And when we take and look at these NOTE Confidence: 0.946962533333333 00:38:31.820 --> 00:38:33.020 different transcription factors, NOTE Confidence: 0.946962533333333 00:38:33.020 --> 00:38:34.777 what we see is that the patterning, NOTE Confidence: 0.946962533333333 00:38:34.780 --> 00:38:37.012 the gene expression that define these NOTE Confidence: 0.946962533333333 00:38:37.012 --> 00:38:39.700 different regions in the brain is disrupted. NOTE Confidence: 0.946962533333333 00:38:39.700 --> 00:38:42.822 So you can see here in the NOTE Confidence: 0.946962533333333 00:38:42.822 --> 00:38:45.158 ARX and it's a a loss. NOTE Confidence: 0.946962533333333 00:38:45.158 --> 00:38:48.386 Of your frontal cortex and a NOTE Confidence: 0.946962533333333 00:38:48.386 --> 00:38:51.699 expansion of the ventral cortex. NOTE Confidence: 0.946962533333333 00:38:51.700 --> 00:38:56.576 When we lose a RX and to try and then map, NOTE Confidence: 0.946962533333333 00:38:56.580 --> 00:38:58.659 but we want to try and map, NOTE Confidence: 0.946962533333333 00:38:58.660 --> 00:38:59.360 well, OK, NOTE Confidence: 0.946962533333333 00:38:59.360 --> 00:39:01.110 these these these regions are NOTE Confidence: 0.946962533333333 00:39:01.110 --> 00:39:03.420 abnormal and the behaviors abnormal. NOTE Confidence: 0.946962533333333 00:39:03.420 --> 00:39:05.100 Can we connect those two? NOTE Confidence: 0.946962533333333 00:39:05.100 --> 00:39:07.500 So we wanted to look at the actual NOTE Confidence: 0.946962533333333 00:39:07.500 --> 00:39:08.915 Axon trajectories from these NOTE Confidence: 0.946962533333333 00:39:08.915 --> 00:39:10.415 different regions to strike, NOTE Confidence: 0.946962533333333 00:39:10.420 --> 00:39:12.690 start mapping that out and NOTE Confidence: 0.946962533333333 00:39:12.690 --> 00:39:15.890 so we can go into a mouse. NOTE Confidence: 0.946962533333333 00:39:15.890 --> 00:39:17.954 And we can actually inject these NOTE Confidence: 0.946962533333333 00:39:17.954 --> 00:39:19.716 different tracers that go along NOTE Confidence: 0.946962533333333 00:39:19.716 --> 00:39:21.648 axons are ones that cross axons. NOTE Confidence: 0.946962533333333 00:39:21.650 --> 00:39:23.290 And when we do that, NOTE Confidence: 0.946962533333333 00:39:23.290 --> 00:39:24.730 what you can see here in the sensory, NOTE Confidence: 0.946962533333333 00:39:24.730 --> 00:39:26.490 so this is Ventrilateral, NOTE Confidence: 0.946962533333333 00:39:26.490 --> 00:39:28.250 this is ventral posterior. NOTE Confidence: 0.946962533333333 00:39:28.250 --> 00:39:31.379 You can see the normal mapping of NOTE Confidence: 0.946962533333333 00:39:31.379 --> 00:39:33.946 the ventral lateral from the brain. NOTE Confidence: 0.946962533333333 00:39:33.946 --> 00:39:36.682 But here the ventral posterior despite NOTE Confidence: 0.946962533333333 00:39:36.682 --> 00:39:38.822 you having normal axons coming NOTE Confidence: 0.946962533333333 00:39:38.822 --> 00:39:40.366 through the internal commissure, NOTE Confidence: 0.946962533333333 00:39:40.370 --> 00:39:42.066 sorry, the internal capsule. NOTE Confidence: 0.946962533333333 00:39:42.066 --> 00:39:44.610 They don't go to ventral posterior. NOTE Confidence: 0.946962533333333 00:39:44.610 --> 00:39:47.193 So we can show very specific mapping NOTE Confidence: 0.946962533333333 00:39:47.193 --> 00:39:49.271 abnormalities and then correlate those NOTE Confidence: 0.946962533333333 00:39:49.271 --> 00:39:51.075 with these behavioral abnormalities NOTE Confidence: 0.946962533333333 00:39:51.075 --> 00:39:53.569 that we're seeing in the brain. NOTE Confidence: 0.946962533333333 00:39:53.570 --> 00:39:56.618 So we're going everywhere from the NOTE Confidence: 0.946962533333333 00:39:56.618 --> 00:39:58.466 molecular understanding of how the NOTE Confidence: 0.946962533333333 00:39:58.466 --> 00:40:00.899 cortex is defined to how that sets NOTE Confidence: 0.946962533333333 00:40:00.899 --> 00:40:02.694 up projections and connections and NOTE Confidence: 0.946962533333333 00:40:02.694 --> 00:40:04.768 what that does for the behavior NOTE Confidence: 0.946962533333333 00:40:04.768 --> 00:40:07.048 of the brain giving us a really a NOTE Confidence: 0.946962533333333 00:40:07.050 --> 00:40:10.260 view from behavior to the molecule. NOTE Confidence: 0.946962533333333 00:40:10.260 --> 00:40:12.990 In the brain and in these developmental NOTE Confidence: 0.946962533333333 00:40:12.990 --> 00:40:13.380 disorders. NOTE Confidence: 0.947441742857143 00:40:16.100 --> 00:40:17.857 So that's some ongoing work we're doing. NOTE Confidence: 0.947441742857143 00:40:17.860 --> 00:40:20.947 And and now I want to shift a little NOTE Confidence: 0.947441742857143 00:40:20.947 --> 00:40:23.779 bit in the last 15 minutes or so NOTE Confidence: 0.947441742857143 00:40:23.780 --> 00:40:26.012 and talk about some other relatively NOTE Confidence: 0.947441742857143 00:40:26.012 --> 00:40:28.416 new work we've been doing and that NOTE Confidence: 0.947441742857143 00:40:28.416 --> 00:40:31.340 is related to these two brains. NOTE Confidence: 0.947441742857143 00:40:31.340 --> 00:40:34.460 So I already told you about this or NOTE Confidence: 0.947441742857143 00:40:34.460 --> 00:40:37.811 showed you the brain of the ARX with an NOTE Confidence: 0.947441742857143 00:40:37.811 --> 00:40:39.750 alanine tract expansion where you have an. NOTE Confidence: 0.947441742857143 00:40:39.750 --> 00:40:43.278 A structurally normal brain, but with NOTE Confidence: 0.947441742857143 00:40:43.278 --> 00:40:45.630 epilepsy and intellectual disabilities. NOTE Confidence: 0.947441742857143 00:40:45.630 --> 00:40:50.256 Now these two kids also have epilepsy, NOTE Confidence: 0.947441742857143 00:40:50.256 --> 00:40:52.494 mild intellectual disabilities, NOTE Confidence: 0.947441742857143 00:40:52.494 --> 00:40:56.224 but a structurally normal brain. NOTE Confidence: 0.947441742857143 00:40:56.230 --> 00:40:58.106 Now there may be some signal abnormality. NOTE Confidence: 0.947441742857143 00:40:58.110 --> 00:41:00.070 You can see a little bit of brightness NOTE Confidence: 0.947441742857143 00:41:00.070 --> 00:41:01.947 here in the thalamus and in the NOTE Confidence: 0.947441742857143 00:41:01.947 --> 00:41:03.550 basal ganglia here in this one. NOTE Confidence: 0.947441742857143 00:41:03.550 --> 00:41:05.748 And and that's typical of these disorders. NOTE Confidence: 0.947441742857143 00:41:05.750 --> 00:41:09.758 These are due to mitochondrial disorders. NOTE Confidence: 0.947441742857143 00:41:09.760 --> 00:41:11.895 So these are mitochondrial related NOTE Confidence: 0.947441742857143 00:41:11.895 --> 00:41:14.402 epilepsies and these have always been NOTE Confidence: 0.947441742857143 00:41:14.402 --> 00:41:16.802 thought to be due to a energy problem NOTE Confidence: 0.947441742857143 00:41:16.802 --> 00:41:19.274 that the the might be neurons require NOTE Confidence: 0.947441742857143 00:41:19.274 --> 00:41:21.571 a tremendous amount of of energy and NOTE Confidence: 0.947441742857143 00:41:21.571 --> 00:41:23.353 you just have an energy deficiency. NOTE Confidence: 0.947441742857143 00:41:23.360 --> 00:41:24.680 If we could replace that, NOTE Confidence: 0.947441742857143 00:41:24.680 --> 00:41:26.675 we'd be able to fix their epilepsy. NOTE Confidence: 0.947441742857143 00:41:26.680 --> 00:41:28.423 Turns out it hasn't been that simple NOTE Confidence: 0.947441742857143 00:41:28.423 --> 00:41:30.479 and it it doesn't work that well. NOTE Confidence: 0.947441742857143 00:41:30.480 --> 00:41:31.800 So we we started thinking, NOTE Confidence: 0.947441742857143 00:41:31.800 --> 00:41:32.572 you know, NOTE Confidence: 0.947441742857143 00:41:32.572 --> 00:41:34.888 maybe it's more complicated than that. NOTE Confidence: 0.947441742857143 00:41:34.890 --> 00:41:37.018 And so we first looked at the NOTE Confidence: 0.947441742857143 00:41:37.018 --> 00:41:39.475 literature and it turns out that a NOTE Confidence: 0.947441742857143 00:41:39.475 --> 00:41:41.320 significant percentage of kids that NOTE Confidence: 0.947441742857143 00:41:41.320 --> 00:41:43.523 have mitochondrial disorders have NOTE Confidence: 0.947441742857143 00:41:43.523 --> 00:41:48.570 either abnormal Eegs or frank epilepsy. NOTE Confidence: 0.947441742857143 00:41:48.570 --> 00:41:51.895 And so we started studying this and NOTE Confidence: 0.947441742857143 00:41:51.895 --> 00:41:53.890 we looked at both the excitatory and NOTE Confidence: 0.947441742857143 00:41:53.890 --> 00:41:55.768 inhibitory neurons because our prediction is, NOTE Confidence: 0.947441742857143 00:41:55.770 --> 00:41:57.774 remember the inhibitory when you have NOTE Confidence: 0.947441742857143 00:41:57.774 --> 00:42:00.369 a defect in the excitatory neurons, NOTE Confidence: 0.947441742857143 00:42:00.370 --> 00:42:01.610 the brains are structurally normal, NOTE Confidence: 0.947441742857143 00:42:01.610 --> 00:42:04.928 but with inhibitory neurons you get a. NOTE Confidence: 0.947441742857143 00:42:04.930 --> 00:42:07.506 Seizures and intellectual disabilities. NOTE Confidence: 0.947441742857143 00:42:07.506 --> 00:42:12.112 So on the left side we've labeled NOTE Confidence: 0.947441742857143 00:42:12.112 --> 00:42:15.567 migrating excitatory neurons in green, NOTE Confidence: 0.947441742857143 00:42:15.570 --> 00:42:18.210 and then in red we've labeled NOTE Confidence: 0.947441742857143 00:42:18.210 --> 00:42:19.090 their mitochondria. NOTE Confidence: 0.947441742857143 00:42:19.090 --> 00:42:21.498 And what you can see is it migrates NOTE Confidence: 0.947441742857143 00:42:21.498 --> 00:42:23.226 across is that the mitochondria NOTE Confidence: 0.947441742857143 00:42:23.226 --> 00:42:25.836 stay just in front of the cell body NOTE Confidence: 0.947441742857143 00:42:25.836 --> 00:42:27.607 as it migrates all the way across, NOTE Confidence: 0.947441742857143 00:42:27.610 --> 00:42:28.602 and we've mapped that. NOTE Confidence: 0.947441742857143 00:42:28.602 --> 00:42:31.300 At the top you can see a quantitation NOTE Confidence: 0.947441742857143 00:42:31.300 --> 00:42:32.510 of that. NOTE Confidence: 0.947441742857143 00:42:32.510 --> 00:42:33.750 But if you look at the of the, NOTE Confidence: 0.947441742857143 00:42:33.750 --> 00:42:34.054 sorry, NOTE Confidence: 0.947441742857143 00:42:34.054 --> 00:42:36.486 the one on the right that's in a NOTE Confidence: 0.947441742857143 00:42:36.486 --> 00:42:38.262 migrating inhibitory neuron and NOTE Confidence: 0.947441742857143 00:42:38.262 --> 00:42:39.670 the mitochondria behave very NOTE Confidence: 0.947441742857143 00:42:39.670 --> 00:42:41.430 differently in all of them. NOTE Confidence: 0.947441742857143 00:42:41.430 --> 00:42:42.220 Inhibitory neurons, NOTE Confidence: 0.947441742857143 00:42:42.220 --> 00:42:44.590 they move around through the cells. NOTE Confidence: 0.947441742857143 00:42:44.590 --> 00:42:45.570 Sometimes they go up NOTE Confidence: 0.947441742857143 00:42:45.570 --> 00:42:46.550 into the leading process, NOTE Confidence: 0.947441742857143 00:42:46.550 --> 00:42:48.126 particularly at branch points, NOTE Confidence: 0.947441742857143 00:42:48.126 --> 00:42:50.490 sometimes they're behind the cell body NOTE Confidence: 0.947441742857143 00:42:50.554 --> 00:42:52.668 and sometimes they're in front of it. NOTE Confidence: 0.947441742857143 00:42:52.670 --> 00:42:53.270 So there's this NOTE Confidence: 0.95434236 00:42:55.910 --> 00:42:57.705 tremendous dynamic movement in the NOTE Confidence: 0.95434236 00:42:57.705 --> 00:42:59.500 inhibitory neurons that you don't NOTE Confidence: 0.95434236 00:42:59.562 --> 00:43:01.147 see in the excitatory neurons. NOTE Confidence: 0.95434236 00:43:01.150 --> 00:43:03.070 And so to study this further, NOTE Confidence: 0.95434236 00:43:03.070 --> 00:43:04.670 so this is just observation, NOTE Confidence: 0.95434236 00:43:04.670 --> 00:43:06.790 we actually started to interrogate NOTE Confidence: 0.95434236 00:43:06.790 --> 00:43:09.335 that we used a genetic model NOTE Confidence: 0.95434236 00:43:09.335 --> 00:43:12.170 where we removed this Ant 1-2, NOTE Confidence: 0.95434236 00:43:12.170 --> 00:43:15.830 this is a transporter of a TP. NOTE Confidence: 0.95434236 00:43:15.830 --> 00:43:17.930 We also did it pharmacologically NOTE Confidence: 0.95434236 00:43:17.930 --> 00:43:19.190 using boncretic acid, NOTE Confidence: 0.95434236 00:43:19.190 --> 00:43:21.605 which actually is an inhibitor of this NOTE Confidence: 0.95434236 00:43:21.605 --> 00:43:23.526 transporter or we used oligomycin, NOTE Confidence: 0.95434236 00:43:23.526 --> 00:43:26.527 which is an inhibitor of the last NOTE Confidence: 0.95434236 00:43:26.527 --> 00:43:29.297 step in the oxidative phosphorylation. NOTE Confidence: 0.95434236 00:43:29.300 --> 00:43:30.540 And I will tell you, NOTE Confidence: 0.95434236 00:43:30.540 --> 00:43:32.538 but I'm not going to show you any data NOTE Confidence: 0.95434236 00:43:32.540 --> 00:43:34.815 to ensure that it wasn't just lycolysis. NOTE Confidence: 0.95434236 00:43:34.820 --> 00:43:35.876 We blocked lycolysis. NOTE Confidence: 0.95434236 00:43:35.876 --> 00:43:38.700 What we were able to show is that NOTE Confidence: 0.95434236 00:43:38.700 --> 00:43:40.300 radial migration is completely NOTE Confidence: 0.90250405 00:43:46.760 --> 00:43:48.304 whereas the inhibitory neuron NOTE Confidence: 0.90250405 00:43:48.304 --> 00:43:50.234 is required for is requires NOTE Confidence: 0.90250405 00:43:50.234 --> 00:43:51.600 oxidative phosphorylation. NOTE Confidence: 0.90250405 00:43:51.600 --> 00:43:52.656 But I'm not going to talk NOTE Confidence: 0.90250405 00:43:52.656 --> 00:43:53.360 about that part again, NOTE Confidence: 0.90250405 00:43:53.360 --> 00:43:56.466 this has been published now if NOTE Confidence: 0.90250405 00:43:56.466 --> 00:43:59.160 you look, let's see, let's. NOTE Confidence: 0.944566485714286 00:44:01.240 --> 00:44:02.717 How come these movies are not playing? NOTE Confidence: 0.91832676 00:44:06.640 --> 00:44:08.120 They were working a second ago. Okay, NOTE Confidence: 0.914349101818182 00:44:11.320 --> 00:44:13.208 I'm not going to be able to show NOTE Confidence: 0.914349101818182 00:44:13.208 --> 00:44:16.000 you these movies on your left is in NOTE Confidence: 0.914349101818182 00:44:16.000 --> 00:44:19.030 in culture looking at inhibitory NOTE Confidence: 0.914349101818182 00:44:19.030 --> 00:44:22.352 neurons and what you'd see is that NOTE Confidence: 0.914349101818182 00:44:22.352 --> 00:44:25.537 that on the top, a normal one. NOTE Confidence: 0.914349101818182 00:44:25.537 --> 00:44:27.832 These, these inhibitory neurons have NOTE Confidence: 0.914349101818182 00:44:27.832 --> 00:44:29.859 tremendous branching as they migrate. NOTE Confidence: 0.914349101818182 00:44:29.860 --> 00:44:32.058 And it it'll just kind of zoom NOTE Confidence: 0.914349101818182 00:44:32.058 --> 00:44:34.290 across the the field at the bottom. NOTE Confidence: 0.914349101818182 00:44:34.290 --> 00:44:36.696 What you'll see is that when you add NOTE Confidence: 0.914349101818182 00:44:36.696 --> 00:44:39.208 oligomycin or when we do it with bancrecic NOTE Confidence: 0.914349101818182 00:44:39.208 --> 00:44:41.379 acid or when we do it genetically, NOTE Confidence: 0.914349101818182 00:44:41.380 --> 00:44:43.459 they don't just migrate across the field. NOTE Confidence: 0.914349101818182 00:44:43.460 --> 00:44:45.924 They go forward and then you see a NOTE Confidence: 0.914349101818182 00:44:45.924 --> 00:44:48.203 leading process coming out of the rear NOTE Confidence: 0.914349101818182 00:44:48.203 --> 00:44:50.209 and the cell actually turning around NOTE Confidence: 0.914349101818182 00:44:50.209 --> 00:44:52.243 and going backwards and going back NOTE Confidence: 0.914349101818182 00:44:52.243 --> 00:44:54.168 and forth and not branching as much. NOTE Confidence: 0.914349101818182 00:44:54.168 --> 00:44:56.111 And then if you look in the genetic NOTE Confidence: 0.914349101818182 00:44:56.111 --> 00:44:57.707 model where we actually are looking NOTE Confidence: 0.914349101818182 00:44:57.707 --> 00:44:59.229 at the cells migrating up, NOTE Confidence: 0.914349101818182 00:44:59.230 --> 00:45:00.862 you'll see a defect in those NOTE Confidence: 0.914349101818182 00:45:00.862 --> 00:45:02.629 cells going up into the cortex, NOTE Confidence: 0.914349101818182 00:45:02.630 --> 00:45:06.068 these inhibitory neurons. NOTE Confidence: 0.914349101818182 00:45:06.070 --> 00:45:10.590 What what we found is that when we do this, NOTE Confidence: 0.914349101818182 00:45:10.590 --> 00:45:12.830 we. So why do cells turn around? NOTE Confidence: 0.914349101818182 00:45:12.830 --> 00:45:14.380 It turns out all epithelial NOTE Confidence: 0.914349101818182 00:45:14.380 --> 00:45:15.631 cells are polarized, right? NOTE Confidence: 0.914349101818182 00:45:15.631 --> 00:45:16.594 And they're polarized. NOTE Confidence: 0.914349101818182 00:45:16.594 --> 00:45:19.228 You have the nucleus and then you have the NOTE Confidence: 0.914349101818182 00:45:19.230 --> 00:45:21.830 MTOC, the microtubule organizing center. NOTE Confidence: 0.914349101818182 00:45:21.830 --> 00:45:23.228 It's also known as the centriole. NOTE Confidence: 0.914349101818182 00:45:23.230 --> 00:45:24.030 In the dividing cell, NOTE Confidence: 0.914349101818182 00:45:24.030 --> 00:45:24.830 it's the same thing. NOTE Confidence: 0.914349101818182 00:45:24.830 --> 00:45:26.546 It's where the microtubules are organized NOTE Confidence: 0.914320166 00:45:29.030 --> 00:45:31.706 as cells migrate that that MTOC moves NOTE Confidence: 0.914320166 00:45:31.706 --> 00:45:33.512 out into the leading process and then NOTE Confidence: 0.914320166 00:45:33.512 --> 00:45:35.306 the nucleus gets pulled behind it. NOTE Confidence: 0.914320166 00:45:35.310 --> 00:45:37.390 That's how they migrate out. NOTE Confidence: 0.914320166 00:45:37.390 --> 00:45:38.758 But in these cells, NOTE Confidence: 0.914320166 00:45:38.758 --> 00:45:40.468 when you lose the mitochondria, NOTE Confidence: 0.914320166 00:45:40.470 --> 00:45:42.094 you lose that polarization. NOTE Confidence: 0.914320166 00:45:42.094 --> 00:45:44.530 And both in the genetic model NOTE Confidence: 0.914320166 00:45:44.601 --> 00:45:46.876 and in the pharmacologic models. NOTE Confidence: 0.914320166 00:45:46.880 --> 00:45:49.280 The mitochondria, sorry, the MTOC, NOTE Confidence: 0.914320166 00:45:49.280 --> 00:45:51.160 is found over the top of the nucleus NOTE Confidence: 0.914320166 00:45:51.160 --> 00:45:52.837 or sometimes even behind the nucleus, NOTE Confidence: 0.914320166 00:45:52.840 --> 00:45:54.015 and that's when those cells NOTE Confidence: 0.914320166 00:45:54.015 --> 00:45:54.720 are turning around. NOTE Confidence: 0.914320166 00:45:54.720 --> 00:45:57.751 So you're losing the polar polarity that NOTE Confidence: 0.914320166 00:45:57.751 --> 00:46:00.639 a normal epithelial cell in a neuron has. NOTE Confidence: 0.914320166 00:46:00.640 --> 00:46:04.600 And that's what we have found NOTE Confidence: 0.914320166 00:46:04.600 --> 00:46:06.268 so more recently, NOTE Confidence: 0.914320166 00:46:06.268 --> 00:46:10.160 and that that works all been published. NOTE Confidence: 0.914320166 00:46:10.160 --> 00:46:11.946 So more recently we started asking, well, NOTE Confidence: 0.914320166 00:46:11.946 --> 00:46:14.268 mitochondria move through the cell, why? NOTE Confidence: 0.914320166 00:46:14.268 --> 00:46:16.984 Why are they moving in inhibitory neurons? NOTE Confidence: 0.914320166 00:46:16.990 --> 00:46:19.636 And it turns out that mitochondria are NOTE Confidence: 0.914320166 00:46:19.636 --> 00:46:21.989 moved along using molecular motors, NOTE Confidence: 0.914320166 00:46:21.990 --> 00:46:24.549 moved along microtubules. NOTE Confidence: 0.914320166 00:46:24.550 --> 00:46:26.950 And so we started thinking about, NOTE Confidence: 0.914320166 00:46:26.950 --> 00:46:27.634 you know, NOTE Confidence: 0.914320166 00:46:27.634 --> 00:46:29.782 how could we disrupt that and NOTE Confidence: 0.914320166 00:46:29.782 --> 00:46:32.006 the way that the mitochondria NOTE Confidence: 0.914320166 00:46:32.006 --> 00:46:33.990 attached these molecular motors, NOTE Confidence: 0.914320166 00:46:33.990 --> 00:46:36.684 because dyneins and kinesins move many NOTE Confidence: 0.914320166 00:46:36.684 --> 00:46:39.190 types of cargo throughout the cell, NOTE Confidence: 0.914320166 00:46:39.190 --> 00:46:41.386 putting things that like Polybee studying, NOTE Confidence: 0.914320166 00:46:41.390 --> 00:46:43.958 but the they they attached to NOTE Confidence: 0.914320166 00:46:43.958 --> 00:46:45.670 the mitochondria using these. NOTE Confidence: 0.914320166 00:46:45.670 --> 00:46:46.470 Adapter proteins, NOTE Confidence: 0.914320166 00:46:46.470 --> 00:46:49.270 which are called mirror one and mirror NOTE Confidence: 0.914320166 00:46:49.270 --> 00:46:52.070 two and there's another one called track, NOTE Confidence: 0.914320166 00:46:52.070 --> 00:46:53.906 Now mirror one and mirror two, NOTE Confidence: 0.914320166 00:46:53.910 --> 00:46:55.686 sorry, mirror two is almost not NOTE Confidence: 0.914320166 00:46:55.686 --> 00:46:57.230 expressed in the developing brain. NOTE Confidence: 0.914320166 00:46:57.230 --> 00:46:59.785 So we just focused on mirror one. NOTE Confidence: 0.914320166 00:46:59.790 --> 00:47:02.790 And so mirror one's the main adapter protein. NOTE Confidence: 0.914320166 00:47:02.790 --> 00:47:05.230 And if we take a knockout mirror one, NOTE Confidence: 0.914320166 00:47:05.230 --> 00:47:07.378 what you see is hearing in NOTE Confidence: 0.914320166 00:47:07.378 --> 00:47:09.630 normal mice in radial migration, NOTE Confidence: 0.914320166 00:47:09.630 --> 00:47:12.340 you can see that the. NOTE Confidence: 0.914320166 00:47:12.340 --> 00:47:13.492 Mitochondria are always out NOTE Confidence: 0.914320166 00:47:13.492 --> 00:47:14.932 at the front of that, NOTE Confidence: 0.914320166 00:47:14.940 --> 00:47:16.578 just like I showed you before, NOTE Confidence: 0.914320166 00:47:16.580 --> 00:47:17.876 are always out at the front NOTE Confidence: 0.914320166 00:47:17.876 --> 00:47:18.740 of the leading process. NOTE Confidence: 0.914320166 00:47:18.740 --> 00:47:21.140 These cells are migrating up. NOTE Confidence: 0.914320166 00:47:21.140 --> 00:47:23.280 If you look at the when NOTE Confidence: 0.914320166 00:47:23.280 --> 00:47:24.980 we knock out mirror one, NOTE Confidence: 0.914320166 00:47:24.980 --> 00:47:27.284 most of the time the mirror ones at NOTE Confidence: 0.914320166 00:47:27.284 --> 00:47:29.833 the back of the nucleus and again NOTE Confidence: 0.914320166 00:47:29.833 --> 00:47:31.733 these cells migrate out normally. NOTE Confidence: 0.914320166 00:47:31.740 --> 00:47:33.498 So it's not affecting their migration, NOTE Confidence: 0.914320166 00:47:33.500 --> 00:47:35.275 it's just affecting the localization NOTE Confidence: 0.914320166 00:47:35.275 --> 00:47:36.340 of the mitochondria. NOTE Confidence: 0.914320166 00:47:36.340 --> 00:47:38.340 Sometimes it's even in front and in back, NOTE Confidence: 0.914320166 00:47:38.340 --> 00:47:41.328 like you see here and here. NOTE Confidence: 0.914320166 00:47:41.330 --> 00:47:42.066 In contrast, NOTE Confidence: 0.914320166 00:47:42.066 --> 00:47:44.642 when we look at the inhibitory neurons, NOTE Confidence: 0.914320166 00:47:44.650 --> 00:47:46.421 we see that the the the mitochondria NOTE Confidence: 0.914320166 00:47:46.421 --> 00:47:48.124 all of a sudden just aggregate NOTE Confidence: 0.914320166 00:47:48.124 --> 00:47:49.888 at the front of the cell. NOTE Confidence: 0.914320166 00:47:49.890 --> 00:47:51.846 So we do something called expansion NOTE Confidence: 0.914320166 00:47:51.846 --> 00:47:53.498 microscopy where we can actually NOTE Confidence: 0.914320166 00:47:53.498 --> 00:47:55.528 get a better look at these cells. NOTE Confidence: 0.914320166 00:47:55.530 --> 00:47:57.228 Looking at the mitochondria we see NOTE Confidence: 0.914320166 00:47:57.228 --> 00:47:59.890 not only is are they they stuck, NOTE Confidence: 0.914320166 00:47:59.890 --> 00:48:02.370 but they're also abnormal. NOTE Confidence: 0.914320166 00:48:02.370 --> 00:48:04.536 They become very small and punctate NOTE Confidence: 0.914320166 00:48:04.536 --> 00:48:06.865 as opposed to being nice and NOTE Confidence: 0.914320166 00:48:06.865 --> 00:48:08.485 long and sometimes branched. NOTE Confidence: 0.914320166 00:48:08.490 --> 00:48:09.898 As you see here, NOTE Confidence: 0.914320166 00:48:09.898 --> 00:48:12.650 so this is the defects that we see. NOTE Confidence: 0.914320166 00:48:12.650 --> 00:48:14.870 And we also see the same NOTE Confidence: 0.914320166 00:48:14.870 --> 00:48:15.610 polarization defects. NOTE Confidence: 0.914320166 00:48:15.610 --> 00:48:17.283 So we can look at the direction NOTE Confidence: 0.914320166 00:48:17.283 --> 00:48:18.831 these cells are migrating and we NOTE Confidence: 0.914320166 00:48:18.831 --> 00:48:20.644 this is just how we calculated it. NOTE Confidence: 0.914320166 00:48:20.650 --> 00:48:22.570 Oh, whoops. NOTE Confidence: 0.914320166 00:48:22.570 --> 00:48:24.970 Oh, I must have, sorry I took out a slide. NOTE Confidence: 0.914320166 00:48:24.970 --> 00:48:26.850 But when we quantitate this, NOTE Confidence: 0.914320166 00:48:26.850 --> 00:48:28.272 you can see that there's a NOTE Confidence: 0.914320166 00:48:28.272 --> 00:48:29.220 huge number of cells NOTE Confidence: 0.940812677777778 00:48:29.276 --> 00:48:30.902 that are going in the wrong NOTE Confidence: 0.940812677777778 00:48:30.902 --> 00:48:32.374 direction here. They're all supposed NOTE Confidence: 0.940812677777778 00:48:32.374 --> 00:48:34.210 to be going north up this way. NOTE Confidence: 0.935245477142857 00:48:36.680 --> 00:48:38.790 And these mice are also NOTE Confidence: 0.935245477142857 00:48:38.790 --> 00:48:39.634 behaviorally abnormal. NOTE Confidence: 0.935245477142857 00:48:39.640 --> 00:48:40.792 So normally mice, NOTE Confidence: 0.935245477142857 00:48:40.792 --> 00:48:43.096 if you put these little white NOTE Confidence: 0.935245477142857 00:48:43.096 --> 00:48:45.560 pads like this one you see here, NOTE Confidence: 0.935245477142857 00:48:45.560 --> 00:48:47.839 they build a nest out of it and NOTE Confidence: 0.935245477142857 00:48:47.839 --> 00:48:49.792 you can see the wild type mouse NOTE Confidence: 0.935245477142857 00:48:49.792 --> 00:48:51.450 over there building this nice NOTE Confidence: 0.935245477142857 00:48:51.450 --> 00:48:53.514 normal round nest that they use. NOTE Confidence: 0.935245477142857 00:48:53.520 --> 00:48:55.356 But if you look at these NOTE Confidence: 0.935245477142857 00:48:55.356 --> 00:48:56.274 marijuana knockout mice, NOTE Confidence: 0.935245477142857 00:48:56.280 --> 00:48:58.400 they they don't build a nest at all. NOTE Confidence: 0.935245477142857 00:48:58.400 --> 00:49:00.598 You can see some don't do anything, NOTE Confidence: 0.935245477142857 00:49:00.600 --> 00:49:01.755 some tear it up a little bit, NOTE Confidence: 0.935245477142857 00:49:01.760 --> 00:49:03.237 some tear it up a little more, NOTE Confidence: 0.935245477142857 00:49:03.240 --> 00:49:05.865 but they don't make an organized nest. NOTE Confidence: 0.935245477142857 00:49:05.870 --> 00:49:09.410 They also have a interesting NOTE Confidence: 0.935245477142857 00:49:09.410 --> 00:49:11.344 behavioral phenotype where NOTE Confidence: 0.935245477142857 00:49:11.344 --> 00:49:14.428 they they have a high anxiety. NOTE Confidence: 0.935245477142857 00:49:14.430 --> 00:49:17.374 So the way you test anxiety in the NOTE Confidence: 0.935245477142857 00:49:17.374 --> 00:49:20.354 mouse is that normally a mouse if you NOTE Confidence: 0.935245477142857 00:49:20.354 --> 00:49:23.940 put it into a open field they're they NOTE Confidence: 0.935245477142857 00:49:23.940 --> 00:49:27.068 they'll explore the entire box okay. NOTE Confidence: 0.935245477142857 00:49:27.068 --> 00:49:30.416 But if you if they have. NOTE Confidence: 0.935245477142857 00:49:30.420 --> 00:49:32.202 What's thought to be anxiety and NOTE Confidence: 0.935245477142857 00:49:32.202 --> 00:49:33.524 again you know, anthropomorphosizing. NOTE Confidence: 0.935245477142857 00:49:33.524 --> 00:49:35.220 What a mouse does, NOTE Confidence: 0.935245477142857 00:49:35.220 --> 00:49:36.860 if it has high anxiety, NOTE Confidence: 0.935245477142857 00:49:36.860 --> 00:49:39.220 they will tend to stay outside of the NOTE Confidence: 0.935245477142857 00:49:39.220 --> 00:49:41.660 center and stay at the edges of the box. NOTE Confidence: 0.935245477142857 00:49:41.660 --> 00:49:43.304 And here's what our mice with NOTE Confidence: 0.935245477142857 00:49:43.304 --> 00:49:44.700 mirror one mutations look like. NOTE Confidence: 0.935245477142857 00:49:44.700 --> 00:49:47.787 They stay at the outside of the box as NOTE Confidence: 0.935245477142857 00:49:47.787 --> 00:49:50.819 opposed to exploring the middle of the box. NOTE Confidence: 0.935245477142857 00:49:50.820 --> 00:49:52.650 The other thing that's quite interesting NOTE Confidence: 0.935245477142857 00:49:52.650 --> 00:49:55.311 is if you look at a mouse in what's NOTE Confidence: 0.935245477142857 00:49:55.311 --> 00:49:56.696 called an elevated plus maze, NOTE Confidence: 0.935245477142857 00:49:56.700 --> 00:49:58.708 and this is a little more than an NOTE Confidence: 0.935245477142857 00:49:58.708 --> 00:50:00.179 elevated plus maze because the. NOTE Confidence: 0.935245477142857 00:50:00.180 --> 00:50:03.568 The arms that go up and down NOTE Confidence: 0.935245477142857 00:50:03.568 --> 00:50:05.033 are actually enclosed, NOTE Confidence: 0.935245477142857 00:50:05.033 --> 00:50:08.977 whereas the ones that go sideways are open. NOTE Confidence: 0.935245477142857 00:50:08.980 --> 00:50:09.484 And once again, NOTE Confidence: 0.935245477142857 00:50:09.484 --> 00:50:10.940 if you look at a wild type mouse, NOTE Confidence: 0.935245477142857 00:50:10.940 --> 00:50:12.780 it'll explore all of those. NOTE Confidence: 0.935245477142857 00:50:12.780 --> 00:50:14.016 But interestingly, these mice, NOTE Confidence: 0.935245477142857 00:50:14.016 --> 00:50:16.579 and this is a little different than anxiety. NOTE Confidence: 0.935245477142857 00:50:16.580 --> 00:50:19.500 This is thought to be kind of a NOTE Confidence: 0.935245477142857 00:50:19.500 --> 00:50:21.020 claustrophobia type phenotype. NOTE Confidence: 0.935245477142857 00:50:21.020 --> 00:50:22.802 You see that they don't enter NOTE Confidence: 0.935245477142857 00:50:22.802 --> 00:50:24.300 that closed box at all, NOTE Confidence: 0.935245477142857 00:50:24.300 --> 00:50:26.368 They're anxious about entering NOTE Confidence: 0.935245477142857 00:50:26.368 --> 00:50:27.919 the closed arms. NOTE Confidence: 0.935245477142857 00:50:27.920 --> 00:50:28.572 Of this, NOTE Confidence: 0.935245477142857 00:50:28.572 --> 00:50:30.528 whereas the wild type go through NOTE Confidence: 0.935245477142857 00:50:30.528 --> 00:50:32.879 all of the arms of these boxes. NOTE Confidence: 0.935245477142857 00:50:32.880 --> 00:50:34.256 So again, NOTE Confidence: 0.935245477142857 00:50:34.256 --> 00:50:39.204 these behavioral defects and we think NOTE Confidence: 0.935245477142857 00:50:39.204 --> 00:50:41.314 the brains are structurally normal, NOTE Confidence: 0.935245477142857 00:50:41.320 --> 00:50:43.090 the brains of the kids are NOTE Confidence: 0.935245477142857 00:50:43.090 --> 00:50:43.680 structurally normal. NOTE Confidence: 0.935245477142857 00:50:43.680 --> 00:50:46.000 They have these different NOTE Confidence: 0.935245477142857 00:50:46.000 --> 00:50:47.160 behavioral phenotypes, NOTE Confidence: 0.935245477142857 00:50:47.160 --> 00:50:49.680 they have epilepsy just like these mice do. NOTE Confidence: 0.92769987 00:50:53.070 --> 00:50:54.806 And so we're now looking to see and NOTE Confidence: 0.92769987 00:50:54.806 --> 00:50:56.673 and this is going to be the end of NOTE Confidence: 0.92769987 00:50:56.673 --> 00:50:58.119 the story that we're looking to NOTE Confidence: 0.92769987 00:50:58.119 --> 00:50:59.715 see what the connectivity is and NOTE Confidence: 0.92769987 00:50:59.715 --> 00:51:02.430 what the changes in gene expression NOTE Confidence: 0.92769987 00:51:02.430 --> 00:51:04.242 leading us to really think that NOTE Confidence: 0.92769987 00:51:04.242 --> 00:51:06.026 this epilepsy phenotype that you NOTE Confidence: 0.92769987 00:51:06.026 --> 00:51:07.871 have in the behavioral phenotype NOTE Confidence: 0.92769987 00:51:07.871 --> 00:51:09.830 is not just an energy defect. NOTE Confidence: 0.92769987 00:51:09.830 --> 00:51:12.050 It's actually a neurodevelopmental NOTE Confidence: 0.92769987 00:51:12.050 --> 00:51:14.825 defect from these inhibitory neurons. NOTE Confidence: 0.92769987 00:51:14.830 --> 00:51:16.030 And this is just a summation NOTE Confidence: 0.92769987 00:51:16.030 --> 00:51:17.030 diagram where you see the, NOTE Confidence: 0.958942771428571 00:51:19.790 --> 00:51:20.936 the excitatory neurons, NOTE Confidence: 0.958942771428571 00:51:20.936 --> 00:51:22.464 they migrate out normally. NOTE Confidence: 0.958942771428571 00:51:22.470 --> 00:51:24.318 We don't know that they function normally NOTE Confidence: 0.958942771428571 00:51:24.318 --> 00:51:26.070 with the with without mirror one, NOTE Confidence: 0.958942771428571 00:51:26.070 --> 00:51:27.568 but we know they migrate normally and NOTE Confidence: 0.958942771428571 00:51:27.568 --> 00:51:29.388 they form a structurally normal brain. NOTE Confidence: 0.958942771428571 00:51:29.390 --> 00:51:31.250 But in contrast, these inhibitory NOTE Confidence: 0.958942771428571 00:51:31.250 --> 00:51:33.110 neurons don't migrate out normally. NOTE Confidence: 0.958942771428571 00:51:33.110 --> 00:51:34.720 The mitochondria stay localized right NOTE Confidence: 0.958942771428571 00:51:34.720 --> 00:51:37.006 at the front as opposed to distributing NOTE Confidence: 0.958942771428571 00:51:37.006 --> 00:51:38.866 in different parts of the cell. NOTE Confidence: 0.958942771428571 00:51:38.870 --> 00:51:41.372 And we actually have been able NOTE Confidence: 0.958942771428571 00:51:41.372 --> 00:51:43.908 to show that this is due to NOTE Confidence: 0.958942771428571 00:51:43.910 --> 00:51:46.310 the the the inhibitory neurons. NOTE Confidence: 0.958942771428571 00:51:46.310 --> 00:51:47.682 They need mitochondria in NOTE Confidence: 0.958942771428571 00:51:47.682 --> 00:51:49.397 the rear of the cell. NOTE Confidence: 0.958942771428571 00:51:49.400 --> 00:51:53.075 Because they require a separate type of. NOTE Confidence: 0.958942771428571 00:51:53.080 --> 00:51:55.000 It's kind of like thinking about NOTE Confidence: 0.958942771428571 00:51:55.000 --> 00:51:56.899 squeezing a toothpaste at the back. NOTE Confidence: 0.958942771428571 00:51:56.899 --> 00:51:59.090 They need that for their migration in NOTE Confidence: 0.958942771428571 00:51:59.156 --> 00:52:01.599 addition to the pulling from the front, NOTE Confidence: 0.958942771428571 00:52:01.600 --> 00:52:03.030 whereas the excitatory neurons don't NOTE Confidence: 0.958942771428571 00:52:03.030 --> 00:52:05.320 seem to need that or as much of that. NOTE Confidence: 0.92415216 00:52:07.480 --> 00:52:10.717 So let me end by just doing a NOTE Confidence: 0.92415216 00:52:10.717 --> 00:52:12.312 brief summary and then thanking NOTE Confidence: 0.92415216 00:52:12.312 --> 00:52:13.997 the people who did the work. NOTE Confidence: 0.92415216 00:52:14.000 --> 00:52:15.565 Hopefully I've given you a NOTE Confidence: 0.92415216 00:52:15.565 --> 00:52:17.546 little bit of insight into how NOTE Confidence: 0.92415216 00:52:17.546 --> 00:52:19.316 inner neurons might be involved. NOTE Confidence: 0.92415216 00:52:19.320 --> 00:52:20.592 In these different NOTE Confidence: 0.92415216 00:52:20.592 --> 00:52:21.440 neurodevelopmental disabilities, NOTE Confidence: 0.92415216 00:52:21.440 --> 00:52:24.072 by by being able to tease out the NOTE Confidence: 0.92415216 00:52:24.072 --> 00:52:26.121 specific role of the inhibitory NOTE Confidence: 0.92415216 00:52:26.121 --> 00:52:28.550 neurons in the epilepsy versus the NOTE Confidence: 0.92415216 00:52:28.550 --> 00:52:30.540 structural defects and now even NOTE Confidence: 0.92415216 00:52:30.614 --> 00:52:32.844 the behavioral defects and how NOTE Confidence: 0.92415216 00:52:32.844 --> 00:52:35.074 that affects these different mice. NOTE Confidence: 0.92415216 00:52:35.080 --> 00:52:37.754 We begin to get new insights in NOTE Confidence: 0.917715220833333 00:52:43.680 --> 00:52:45.575 to how these different defects NOTE Confidence: 0.917715220833333 00:52:45.575 --> 00:52:48.200 led to new studies in terms of. NOTE Confidence: 0.917715220833333 00:52:48.200 --> 00:52:49.675 What, how you might be NOTE Confidence: 0.917715220833333 00:52:49.675 --> 00:52:50.560 treating these patients. NOTE Confidence: 0.917715220833333 00:52:50.560 --> 00:52:52.648 So for example through another set NOTE Confidence: 0.917715220833333 00:52:52.648 --> 00:52:54.760 of experiments I didn't talk about, NOTE Confidence: 0.917715220833333 00:52:54.760 --> 00:52:59.548 we there there was identified a an NOTE Confidence: 0.917715220833333 00:52:59.548 --> 00:53:01.124 estrogen related molecule that's NOTE Confidence: 0.917715220833333 00:53:01.124 --> 00:53:03.178 actually pretty effective for the NOTE Confidence: 0.917715220833333 00:53:03.178 --> 00:53:05.238 alanine tract expansion mouse mutants. NOTE Confidence: 0.917715220833333 00:53:05.240 --> 00:53:07.544 And Jeff Nobles and at Baylor gave this NOTE Confidence: 0.917715220833333 00:53:07.544 --> 00:53:09.219 estrogen to these mice and actually NOTE Confidence: 0.917715220833333 00:53:09.219 --> 00:53:11.467 did a very nice job at improving them NOTE Confidence: 0.917715220833333 00:53:11.467 --> 00:53:13.679 and that went into a clinical trial NOTE Confidence: 0.917715220833333 00:53:13.679 --> 00:53:16.415 which I actually don't know the results of. NOTE Confidence: 0.917715220833333 00:53:16.420 --> 00:53:19.756 It also has led to several different groups NOTE Confidence: 0.917715220833333 00:53:19.756 --> 00:53:23.655 now looking at replacing the inhibitory NOTE Confidence: 0.917715220833333 00:53:23.655 --> 00:53:26.458 neurons using differentiated IPSC cells. NOTE Confidence: 0.917715220833333 00:53:26.458 --> 00:53:28.612 And so you're specifically looking at NOTE Confidence: 0.917715220833333 00:53:28.612 --> 00:53:30.655 not just differentiated inter neurons NOTE Confidence: 0.917715220833333 00:53:30.655 --> 00:53:33.602 but even subtypes which I didn't really NOTE Confidence: 0.917715220833333 00:53:33.664 --> 00:53:36.199 talk about specifically parvalbumin as NOTE Confidence: 0.917715220833333 00:53:36.199 --> 00:53:38.734 opposed to the somatostatin subpopulations. NOTE Confidence: 0.917715220833333 00:53:38.740 --> 00:53:40.676 I also hope that I've given you a NOTE Confidence: 0.917715220833333 00:53:40.676 --> 00:53:42.295 little bit insight how different NOTE Confidence: 0.917715220833333 00:53:42.295 --> 00:53:44.670 mutations in the same gene. NOTE Confidence: 0.917715220833333 00:53:44.670 --> 00:53:47.190 Can result in two different phenotypes. NOTE Confidence: 0.917715220833333 00:53:47.190 --> 00:53:49.350 So when you lose that gene you you affect NOTE Confidence: 0.917715220833333 00:53:49.350 --> 00:53:51.430 both excitatory and inhibitory neurons, NOTE Confidence: 0.917715220833333 00:53:51.430 --> 00:53:52.750 at least for a RX, NOTE Confidence: 0.917715220833333 00:53:52.750 --> 00:53:54.230 whereas the alanine tract NOTE Confidence: 0.917715220833333 00:53:54.230 --> 00:53:56.450 expansion only seem to affect one NOTE Confidence: 0.917715220833333 00:53:56.518 --> 00:53:58.590 population of inhibitory neurons, NOTE Confidence: 0.917715220833333 00:53:58.590 --> 00:54:00.250 giving you different phenotypes NOTE Confidence: 0.917715220833333 00:54:00.250 --> 00:54:02.740 in these different cell types and NOTE Confidence: 0.917715220833333 00:54:02.809 --> 00:54:04.789 therefore different phenotypes. NOTE Confidence: 0.917715220833333 00:54:04.790 --> 00:54:05.402 I've also, NOTE Confidence: 0.917715220833333 00:54:05.402 --> 00:54:06.626 through the mitochondria work, NOTE Confidence: 0.917715220833333 00:54:06.630 --> 00:54:09.062 talked about how metabolic NOTE Confidence: 0.917715220833333 00:54:09.062 --> 00:54:12.034 perturbations in the inhibitory neurons. NOTE Confidence: 0.917715220833333 00:54:12.034 --> 00:54:14.398 Because they require that NOTE Confidence: 0.917715220833333 00:54:14.398 --> 00:54:15.580 oxidated phosphorylation, NOTE Confidence: 0.917715220833333 00:54:15.580 --> 00:54:17.358 they no longer are able to function NOTE Confidence: 0.917715220833333 00:54:17.358 --> 00:54:19.190 and I think this contributes to NOTE Confidence: 0.917715220833333 00:54:19.190 --> 00:54:20.870 the phenotype in these patients NOTE Confidence: 0.917715220833333 00:54:20.870 --> 00:54:22.852 and really should we should start NOTE Confidence: 0.917715220833333 00:54:22.852 --> 00:54:24.736 thinking about new ways for therapy NOTE Confidence: 0.917715220833333 00:54:24.740 --> 00:54:27.890 as opposed to just trying to correct NOTE Confidence: 0.917715220833333 00:54:27.890 --> 00:54:30.739 the energetics in the brain itself. NOTE Confidence: 0.917715220833333 00:54:30.740 --> 00:54:34.350 So let me end there and really thank NOTE Confidence: 0.917715220833333 00:54:34.350 --> 00:54:36.180 the people that have done this. NOTE Confidence: 0.917715220833333 00:54:36.180 --> 00:54:38.328 All the recent work on the marijuana NOTE Confidence: 0.917715220833333 00:54:38.328 --> 00:54:40.380 has been done by a postdoc in my lab, NOTE Confidence: 0.917715220833333 00:54:40.380 --> 00:54:41.348 Abby Myers, NOTE Confidence: 0.917715220833333 00:54:41.348 --> 00:54:46.076 who just now has a job as a as an NOTE Confidence: 0.917715220833333 00:54:46.076 --> 00:54:48.216 assistant professor at Hamilton College. NOTE Confidence: 0.917715220833333 00:54:48.220 --> 00:54:51.124 The work on the Alanine tract NOTE Confidence: 0.917715220833333 00:54:51.124 --> 00:54:53.860 expansion was done by AM DPHD NOTE Confidence: 0.917715220833333 00:54:53.860 --> 00:54:57.288 student in in my lab a while back. NOTE Confidence: 0.917715220833333 00:54:57.288 --> 00:54:58.716 MacLean is Ralia. NOTE Confidence: 0.917715220833333 00:54:58.720 --> 00:55:01.254 All the epilepsy work is done in NOTE Confidence: 0.917715220833333 00:55:01.254 --> 00:55:02.800 collaboration with Eric Marsh, NOTE Confidence: 0.917715220833333 00:55:02.800 --> 00:55:04.800 who was a postdoc in my lab and NOTE Confidence: 0.917715220833333 00:55:04.800 --> 00:55:06.680 we still collaborate together. NOTE Confidence: 0.917715220833333 00:55:06.680 --> 00:55:10.886 And the some of the other work I I NOTE Confidence: 0.917715220833333 00:55:10.886 --> 00:55:13.439 mentioned was done by Erica Lynn Hendel. NOTE Confidence: 0.917715220833333 00:55:13.439 --> 00:55:16.637 She did the early mitochondrial work NOTE Confidence: 0.917715220833333 00:55:16.637 --> 00:55:20.157 and all of this is supported and and NOTE Confidence: 0.917715220833333 00:55:20.160 --> 00:55:24.896 really my labs been largely run I would NOTE Confidence: 0.917715220833333 00:55:24.896 --> 00:55:28.030 say by Ginam Cho and now young Shin Lin. NOTE Confidence: 0.917715220833333 00:55:28.030 --> 00:55:29.390 As they've been with me NOTE Confidence: 0.917715220833333 00:55:29.390 --> 00:55:30.750 for a number of years. NOTE Confidence: 0.917715220833333 00:55:30.750 --> 00:55:32.080 So with that I'll stop and I'm NOTE Confidence: 0.917715220833333 00:55:32.080 --> 00:55:33.309 happy to take any questions. NOTE Confidence: 0.917715220833333 00:55:33.310 --> 00:55:34.670 Thank you very much. NOTE Confidence: 0.9301902 00:55:40.870 --> 00:55:41.350 Yes, NOTE Confidence: 0.943608066666667 00:55:44.750 --> 00:55:47.550 didn't show any data, NOTE Confidence: 0.9402536 00:55:47.550 --> 00:55:48.630 but what about NOTE Confidence: 0.9402536 00:55:51.270 --> 00:55:51.430 this NOTE Confidence: 0.9905706 00:55:53.590 --> 00:55:55.708 polarization microphone may actually be NOTE Confidence: 0.87457219 00:55:59.270 --> 00:56:01.070 that could affect migration? NOTE Confidence: 0.917956666666667 00:56:02.120 --> 00:56:04.316 Yeah, yeah. So I you're right, NOTE Confidence: 0.917956666666667 00:56:04.320 --> 00:56:07.080 I didn't show we we have done the NOTE Confidence: 0.917956666666667 00:56:07.080 --> 00:56:08.982 the energetics data looking at a NOTE Confidence: 0.917956666666667 00:56:08.982 --> 00:56:10.952 TP localization in the cell and NOTE Confidence: 0.917956666666667 00:56:10.952 --> 00:56:12.557 it's it's kind of interesting. NOTE Confidence: 0.917956666666667 00:56:12.560 --> 00:56:13.540 I'll come to your calcium NOTE Confidence: 0.917956666666667 00:56:13.540 --> 00:56:14.520 question in just a second. NOTE Confidence: 0.917956666666667 00:56:14.520 --> 00:56:15.896 It's actually very interesting. NOTE Confidence: 0.917956666666667 00:56:15.896 --> 00:56:17.960 If you look at adult neurons, NOTE Confidence: 0.917956666666667 00:56:17.960 --> 00:56:21.230 mitochondria actually have to go out NOTE Confidence: 0.917956666666667 00:56:21.230 --> 00:56:24.435 into the into the processes of the NOTE Confidence: 0.917956666666667 00:56:24.435 --> 00:56:26.930 cell mostly the dendrites where new. NOTE Confidence: 0.917956666666667 00:56:26.930 --> 00:56:28.602 Synapses are being formed. NOTE Confidence: 0.917956666666667 00:56:28.602 --> 00:56:30.692 So synaptic plasticity is highly NOTE Confidence: 0.917956666666667 00:56:30.692 --> 00:56:32.427 dependent on mitochondria being NOTE Confidence: 0.917956666666667 00:56:32.427 --> 00:56:34.517 shuttled through this same mechanism NOTE Confidence: 0.917956666666667 00:56:34.517 --> 00:56:36.725 along with molecular motors out to NOTE Confidence: 0.917956666666667 00:56:36.725 --> 00:56:39.038 those sites and then they move back NOTE Confidence: 0.917956666666667 00:56:39.038 --> 00:56:41.126 as those synapses are being formed. NOTE Confidence: 0.917956666666667 00:56:41.130 --> 00:56:41.490 We think NOTE Confidence: 0.9402536 00:56:47.150 --> 00:56:48.560 that's a similar defect the cell NOTE Confidence: 0.9402536 00:56:48.560 --> 00:56:50.150 and in your it isn't heard. NOTE Confidence: 0.9402536 00:56:50.150 --> 00:56:51.930 I haven't I am showing we have done a little NOTE Confidence: 0.9402536 00:56:51.972 --> 00:56:53.505 bit of calcium signaling on with this. NOTE Confidence: 0.9402536 00:56:53.510 --> 00:56:55.382 We've done it more to look at the epilepsy NOTE Confidence: 0.9402536 00:56:55.382 --> 00:56:57.511 and looking at the calcium waves for example NOTE Confidence: 0.9402536 00:56:57.511 --> 00:56:59.180 in the hippocampus and in the cortex. NOTE Confidence: 0.9402536 00:56:59.180 --> 00:57:01.820 And and there are significant abnormalities. NOTE Confidence: 0.9402536 00:57:01.820 --> 00:57:04.230 We have not yet looked at it in terms of NOTE Confidence: 0.9402536 00:57:04.290 --> 00:57:06.578 intracellular localization of calcium, NOTE Confidence: 0.9402536 00:57:06.580 --> 00:57:08.460 which as you know is is a little bit harder. NOTE Confidence: 0.9402536 00:57:08.460 --> 00:57:11.660 But we that that is something I'd like to do, NOTE Confidence: 0.9402536 00:57:11.660 --> 00:57:12.738 but we just haven't done that yet. NOTE Confidence: 0.9402536 00:57:12.740 --> 00:57:15.700 Yeah. Yeah. So wondering if you NOTE Confidence: 0.9603804 00:57:17.980 --> 00:57:24.164 follow that, but the certain fact is that NOTE Confidence: 0.9603804 00:57:24.164 --> 00:57:26.724 underlying the sociability and anxiety. NOTE Confidence: 0.9603804 00:57:26.730 --> 00:57:29.530 The same circuits affected by epilepsy or NOTE Confidence: 0.9402536 00:57:33.210 --> 00:57:36.820 yeah, it's it's hard to disentangle NOTE Confidence: 0.9402536 00:57:36.820 --> 00:57:39.222 that we think So at least the one NOTE Confidence: 0.9402536 00:57:39.222 --> 00:57:41.088 circuit we have we think correlates NOTE Confidence: 0.9402536 00:57:41.088 --> 00:57:43.325 very nicely with some of the one of NOTE Confidence: 0.9402536 00:57:43.325 --> 00:57:44.850 the behavioral phenotypes that we have. NOTE Confidence: 0.9352219 00:57:46.930 --> 00:57:49.654 When you look at these mice NOTE Confidence: 0.9352219 00:57:49.654 --> 00:57:52.150 and the epilepsy we see a. NOTE Confidence: 0.9352219 00:57:52.150 --> 00:57:54.448 Simultaneous disorganization of NOTE Confidence: 0.9352219 00:57:54.448 --> 00:57:57.670 electrical activity in in both NOTE Confidence: 0.9352219 00:57:57.670 --> 00:57:59.510 hemispheres and both hippocampus. NOTE Confidence: 0.9352219 00:57:59.510 --> 00:58:03.011 So when we when we do our analysis, NOTE Confidence: 0.9352219 00:58:03.011 --> 00:58:05.537 we put two frontal electrodes in NOTE Confidence: 0.9352219 00:58:05.537 --> 00:58:07.829 and two hippocampus electrodes in. NOTE Confidence: 0.9352219 00:58:07.830 --> 00:58:10.270 So we're recording 4 sites NOTE Confidence: 0.9352219 00:58:10.270 --> 00:58:12.600 simultaneously in these mice and NOTE Confidence: 0.9352219 00:58:12.600 --> 00:58:14.450 we see disorganization of the NOTE Confidence: 0.9352219 00:58:14.450 --> 00:58:16.442 cortex in and the hippocampus NOTE Confidence: 0.9352219 00:58:16.442 --> 00:58:19.052 in all areas and seizures can NOTE Confidence: 0.9352219 00:58:19.052 --> 00:58:20.788 come from different locations. NOTE Confidence: 0.9352219 00:58:20.790 --> 00:58:22.785 So we don't think it's circuit specific. NOTE Confidence: 0.9352219 00:58:22.790 --> 00:58:25.400 We think it's a more generalized NOTE Confidence: 0.9352219 00:58:25.400 --> 00:58:27.790 disorganization of the of all the circuits. NOTE Confidence: 0.9402536 00:58:30.190 --> 00:58:30.510 Yeah, NOTE Confidence: 0.9654121 00:58:35.710 --> 00:58:36.630 yeah, absolutely. NOTE Confidence: 0.9402536 00:58:46.350 --> 00:58:46.710 Yeah. NOTE Confidence: 0.6223776 00:58:54.210 --> 00:58:58.651 Yeah, yeah. So we, we started to look NOTE Confidence: 0.6223776 00:58:58.651 --> 00:59:01.430 at both fission and fusion and and NOTE Confidence: 0.6223776 00:59:01.430 --> 00:59:03.685 unfortunately those experiments had fizzled. NOTE Confidence: 0.6223776 00:59:03.690 --> 00:59:06.430 So I don't have any data to NOTE Confidence: 0.6223776 00:59:06.430 --> 00:59:08.690 show you we tried to do that. NOTE Confidence: 0.6223776 00:59:08.690 --> 00:59:11.386 We do think that it's a failure of NOTE Confidence: 0.6223776 00:59:11.386 --> 00:59:12.810 fission as opposed to a fusion. NOTE Confidence: 0.6223776 00:59:12.810 --> 00:59:15.960 We think they can break apart, but. NOTE Confidence: 0.6223776 00:59:15.960 --> 00:59:18.610 When we've studied that, we've studied NOTE Confidence: 0.6223776 00:59:18.610 --> 00:59:21.400 that in a couple different ways. NOTE Confidence: 0.6223776 00:59:21.400 --> 00:59:23.696 The cells get really sick when we NOTE Confidence: 0.6223776 00:59:23.696 --> 00:59:25.959 try and disrupt that specifically. NOTE Confidence: 0.6223776 00:59:25.960 --> 00:59:27.640 And so I don't think we, NOTE Confidence: 0.6223776 00:59:27.640 --> 00:59:29.158 the cells get sick, they die, NOTE Confidence: 0.6223776 00:59:29.160 --> 00:59:30.516 they don't move, they don't divide, NOTE Confidence: 0.6223776 00:59:30.520 --> 00:59:32.200 they don't do a lot of things. NOTE Confidence: 0.6223776 00:59:32.200 --> 00:59:33.256 And so that's been a really NOTE Confidence: 0.6223776 00:59:33.256 --> 00:59:34.359 hard thing for us to study, NOTE Confidence: 0.6223776 00:59:34.360 --> 00:59:35.520 at least in these neurons. NOTE Confidence: 0.6223776 00:59:35.520 --> 00:59:38.240 I know you can study it in other cell types, NOTE Confidence: 0.6223776 00:59:38.240 --> 00:59:40.207 but when we try and introduce some NOTE Confidence: 0.6223776 00:59:40.207 --> 00:59:42.070 of those genes that are involved NOTE Confidence: 0.6223776 00:59:42.070 --> 00:59:43.996 in both fission and fusion or NOTE Confidence: 0.6223776 00:59:43.996 --> 00:59:46.156 actually we've disrupted them. It is. NOTE Confidence: 0.6223776 00:59:46.156 --> 00:59:48.460 It is not gone very well for us. NOTE Confidence: 0.6223776 00:59:48.460 --> 00:59:49.979 So I wish I could answer that. NOTE Confidence: 0.6223776 00:59:49.980 --> 00:59:50.720 We've tried. NOTE Confidence: 0.6223776 00:59:50.720 --> 00:59:52.940 It's a it's a great question NOTE Confidence: 0.6223776 00:59:52.940 --> 00:59:54.256 and I'd like to get an answer, NOTE Confidence: 0.6223776 00:59:54.260 --> 00:59:57.540 but that's been a hard thing to study. NOTE Confidence: 0.6223776 00:59:57.540 --> 00:59:57.900 Yes Sir, NOTE Confidence: 0.850692246 01:00:00.940 --> 01:00:02.764 totally something that NOTE Confidence: 0.850692246 01:00:02.764 --> 01:00:05.084 I'm told it got wrong. NOTE Confidence: 0.850692246 01:00:05.084 --> 01:00:07.806 So I'm really fascinated to try to NOTE Confidence: 0.850692246 01:00:07.806 --> 01:00:10.152 connect with 1/3 of the dollars. NOTE Confidence: 0.850692246 01:00:10.152 --> 01:00:12.240 Seems like there is a rather NOTE Confidence: 0.850692246 01:00:12.240 --> 01:00:13.920 large gap in there. NOTE Confidence: 0.850692246 01:00:13.920 --> 01:00:17.838 I don't get any together or NOTE Confidence: 0.850692246 01:00:17.840 --> 01:00:20.070 just one basic question is NOTE Confidence: 0.850692246 01:00:20.070 --> 01:00:23.520 that's the thing just seems NOTE Confidence: 0.9603802925 01:00:25.920 --> 01:00:27.680 like there's this behavioral. NOTE Confidence: 0.946657475454545 01:00:34.680 --> 01:00:36.612 Yeah, you're right. It's a big NOTE Confidence: 0.946657475454545 01:00:36.612 --> 01:00:38.640 jump from molecular to behavioral. NOTE Confidence: 0.946657475454545 01:00:38.640 --> 01:00:40.464 But that is what we're trying to piece NOTE Confidence: 0.946657475454545 01:00:40.464 --> 01:00:42.160 together one, one part at a time. NOTE Confidence: 0.942266388 01:00:44.490 --> 01:00:48.472 In terms of the specificity, the behavior NOTE Confidence: 0.942266388 01:00:48.472 --> 01:00:52.327 is actually becomes very specific. NOTE Confidence: 0.942266388 01:00:52.330 --> 01:00:54.298 Why can I say that? Well, we do, NOTE Confidence: 0.942266388 01:00:54.298 --> 01:00:56.370 you do this whole battery of tests, NOTE Confidence: 0.942266388 01:00:56.370 --> 01:00:57.418 we did smell tests. NOTE Confidence: 0.942266388 01:00:57.418 --> 01:00:58.990 You do these bearing of different NOTE Confidence: 0.942266388 01:00:59.039 --> 01:01:00.491 marbles and things like that and NOTE Confidence: 0.942266388 01:01:00.491 --> 01:01:02.447 look at how fast they can find them. NOTE Confidence: 0.942266388 01:01:02.450 --> 01:01:07.985 You can do these memory tests you can do. NOTE Confidence: 0.942266388 01:01:07.990 --> 01:01:09.430 You you have to test gate, NOTE Confidence: 0.942266388 01:01:09.430 --> 01:01:11.190 you have to test strength because if they, NOTE Confidence: 0.942266388 01:01:11.190 --> 01:01:12.210 if they're not strong enough NOTE Confidence: 0.942266388 01:01:12.210 --> 01:01:13.358 or they can't walk, they don't, NOTE Confidence: 0.942266388 01:01:13.358 --> 01:01:14.506 they can't do some of these things, NOTE Confidence: 0.942266388 01:01:14.510 --> 01:01:17.390 they won't go over and see that other mouse. NOTE Confidence: 0.942266388 01:01:17.390 --> 01:01:20.134 So there's a whole battery of tests we NOTE Confidence: 0.942266388 01:01:20.134 --> 01:01:22.592 do and show that they're all normal. NOTE Confidence: 0.942266388 01:01:22.592 --> 01:01:24.596 I mean these mice behave normally NOTE Confidence: 0.942266388 01:01:24.596 --> 01:01:26.546 in in almost all these tests, NOTE Confidence: 0.942266388 01:01:26.550 --> 01:01:29.028 but it gets very specific for these NOTE Confidence: 0.942266388 01:01:29.028 --> 01:01:30.459 socialization tests where we've NOTE Confidence: 0.942266388 01:01:30.459 --> 01:01:33.197 see all the defects. So the the, NOTE Confidence: 0.942266388 01:01:33.197 --> 01:01:36.760 the specificity of it is very good. NOTE Confidence: 0.942266388 01:01:36.760 --> 01:01:37.760 Now the next step, though, NOTE Confidence: 0.942266388 01:01:37.760 --> 01:01:40.176 is what does it mean? I mean, NOTE Confidence: 0.942266388 01:01:40.176 --> 01:01:41.606 that's the anthropomorphosizing, right? NOTE Confidence: 0.942266388 01:01:41.606 --> 01:01:43.836 What is an autistic mouse? NOTE Confidence: 0.942266388 01:01:43.840 --> 01:01:45.880 I mean, you don't really know that, right? NOTE Confidence: 0.942266388 01:01:45.880 --> 01:01:49.520 So we use these kind of surrogates NOTE Confidence: 0.942266388 01:01:49.520 --> 01:01:52.640 that the field has, has adopted to use. NOTE Confidence: 0.942266388 01:01:52.640 --> 01:01:55.680 And and that's, I think, the best we can do. NOTE Confidence: 0.942266388 01:01:55.680 --> 01:01:56.680 But there is, I think, NOTE Confidence: 0.942266388 01:01:56.680 --> 01:01:58.040 a high degree of specificity. NOTE Confidence: 0.946962478333333 01:02:01.160 --> 01:02:02.219 2 questions. First, NOTE Confidence: 0.946962478333333 01:02:02.219 --> 01:02:04.888 have you gone beyond the fact you NOTE Confidence: 0.946962478333333 01:02:04.888 --> 01:02:06.496 have a transcriptional regulator? NOTE Confidence: 0.946962478333333 01:02:06.500 --> 01:02:10.902 And there's migratory in terms of NOTE Confidence: 0.946962478333333 01:02:10.902 --> 01:02:12.346 looking the downstream mechanism NOTE Confidence: 0.946962478333333 01:02:12.346 --> 01:02:14.420 and what are the gradients NOTE Confidence: 0.946962478333333 01:02:14.420 --> 01:02:17.044 there caused in migratory. NOTE Confidence: 0.946962478333333 01:02:17.044 --> 01:02:19.218 And I'll give you the second question, NOTE Confidence: 0.946962478333333 01:02:19.220 --> 01:02:22.180 if you look at stamping structure, NOTE Confidence: 0.946962478333333 01:02:22.180 --> 01:02:25.180 please sample any change there. NOTE Confidence: 0.930190133333333 01:02:30.540 --> 01:02:32.370 I don't have it in here. Yeah. NOTE Confidence: 0.930190133333333 01:02:32.370 --> 01:02:35.050 So we actually published. NOTE Confidence: 0.930190133333333 01:02:35.050 --> 01:02:35.876 Several articles. NOTE Confidence: 0.930190133333333 01:02:35.876 --> 01:02:37.808 They're all in J. Neuroscience. NOTE Confidence: 0.930190133333333 01:02:37.808 --> 01:02:39.754 Dan Lysco was a graduate student in NOTE Confidence: 0.930190133333333 01:02:39.754 --> 01:02:41.732 my lab who was really interested in NOTE Confidence: 0.930190133333333 01:02:41.732 --> 01:02:44.086 this and and he started looking at NOTE Confidence: 0.930190133333333 01:02:44.086 --> 01:02:45.470 gradients of different molecules NOTE Confidence: 0.930190133333333 01:02:45.534 --> 01:02:47.580 and their role in the migration NOTE Confidence: 0.930190133333333 01:02:47.580 --> 01:02:49.876 and actually connecting the NOTE Confidence: 0.930190133333333 01:02:49.876 --> 01:02:53.190 gradients of different things, NOTE Confidence: 0.930190133333333 01:02:53.190 --> 01:02:55.140 particularly in the wind signaling NOTE Confidence: 0.930190133333333 01:02:55.140 --> 01:02:57.090 pathway which is expressed NOTE Confidence: 0.930190133333333 01:02:57.090 --> 01:03:00.978 both in the meninges and in the NOTE Confidence: 0.930190133333333 01:03:00.978 --> 01:03:03.306 that that migratory stream. NOTE Confidence: 0.930190133333333 01:03:03.310 --> 01:03:06.154 And show that that went signaling NOTE Confidence: 0.930190133333333 01:03:06.154 --> 01:03:08.625 going through the receptors through NOTE Confidence: 0.930190133333333 01:03:08.625 --> 01:03:10.613 the frizzled receptors actually NOTE Confidence: 0.930190133333333 01:03:10.613 --> 01:03:14.111 connects to the micro to the both NOTE Confidence: 0.930190133333333 01:03:14.111 --> 01:03:15.922 actin and microtubule cytoskeleton NOTE Confidence: 0.930190133333333 01:03:15.922 --> 01:03:18.806 and affects the ability of that to NOTE Confidence: 0.930190133333333 01:03:18.806 --> 01:03:21.070 branch and do things in the migration. NOTE Confidence: 0.921062423 01:03:27.990 --> 01:03:31.448 So, so that and. And also the NOTE Confidence: 0.921062423 01:03:31.448 --> 01:03:34.698 the other one actually that he NOTE Confidence: 0.921062423 01:03:34.698 --> 01:03:38.920 studied even more was SD F4 and so NOTE Confidence: 0.934662822222222 01:03:42.160 --> 01:03:45.104 CDCX CR4 and CX CL12 which is the NOTE Confidence: 0.934662822222222 01:03:45.104 --> 01:03:47.436 ligand and he was able to show NOTE Confidence: 0.934662822222222 01:03:47.436 --> 01:03:49.358 that those are modulated by a RX. NOTE Confidence: 0.943128857142857 01:03:52.000 --> 01:03:53.519 We haven't looked at all at synaptic, NOTE Confidence: 0.943128857142857 01:03:53.520 --> 01:03:54.955 it would be another area to go, NOTE Confidence: 0.943128857142857 01:03:54.960 --> 01:03:57.320 but we have not done that, yeah. NOTE Confidence: 0.93019015 01:04:01.560 --> 01:04:05.000 Look at the difference that make this NOTE Confidence: 0.9503169 01:04:07.040 --> 01:04:11.080 thing to run out or in NOTE Confidence: 0.933544596666667 01:04:14.000 --> 01:04:14.879 human and so NOTE Confidence: 0.948304255 01:04:17.840 --> 01:04:21.008 we've kind of we've done descriptive NOTE Confidence: 0.948304255 01:04:21.008 --> 01:04:24.572 pathology in the human and we've been able NOTE Confidence: 0.948304255 01:04:24.572 --> 01:04:28.068 to look at 2 humans with a RX mutations. NOTE Confidence: 0.948304255 01:04:28.070 --> 01:04:29.918 And they do have a deficit in NOTE Confidence: 0.948304255 01:04:29.918 --> 01:04:31.126 the inhibitory neurons that's NOTE Confidence: 0.948304255 01:04:31.126 --> 01:04:32.906 greater than their excitatory ones. NOTE Confidence: 0.948304255 01:04:32.910 --> 01:04:34.950 But the the two brains we've looked at NOTE Confidence: 0.948304255 01:04:34.950 --> 01:04:36.988 both had the Liz encephalophenotype. NOTE Confidence: 0.948304255 01:04:36.990 --> 01:04:39.160 So they also had a, a structural defect. NOTE Confidence: 0.948304255 01:04:39.160 --> 01:04:42.310 So it wasn't so easy to parse that out. NOTE Confidence: 0.948304255 01:04:42.310 --> 01:04:43.590 And then we, you know, NOTE Confidence: 0.948304255 01:04:43.590 --> 01:04:45.110 most of the works been in the mouse. NOTE Confidence: 0.948304255 01:04:45.110 --> 01:04:46.268 We have not been able to, NOTE Confidence: 0.948304255 01:04:46.270 --> 01:04:48.722 we've not done anything in the humans in NOTE Confidence: 0.948304255 01:04:48.722 --> 01:04:50.864 terms of trying to study the migration, NOTE Confidence: 0.948304255 01:04:50.870 --> 01:04:52.910 but we'd like to do that. NOTE Confidence: 0.948304255 01:04:52.910 --> 01:04:57.102 And just recently, I've gotten 2 patients. NOTE Confidence: 0.948304255 01:04:57.102 --> 01:04:59.326 They're they're actually brothers NOTE Confidence: 0.948304255 01:04:59.326 --> 01:05:02.580 that have a RX mutations. NOTE Confidence: 0.948304255 01:05:02.580 --> 01:05:04.458 The parents have consented and we've NOTE Confidence: 0.948304255 01:05:04.458 --> 01:05:06.938 gotten and we're in the process of making NOTE Confidence: 0.948304255 01:05:06.940 --> 01:05:09.580 IPSC's from those ARX mutation patients, NOTE Confidence: 0.948304255 01:05:09.580 --> 01:05:12.140 which are going to allow us to then NOTE Confidence: 0.948304255 01:05:12.140 --> 01:05:15.019 look at the migration of those cells, NOTE Confidence: 0.948304255 01:05:15.020 --> 01:05:16.798 both putting them into like nude mice NOTE Confidence: 0.948304255 01:05:16.798 --> 01:05:19.040 but also in culture to be able to study NOTE Confidence: 0.948304255 01:05:19.040 --> 01:05:21.075 how do they behave when we differentiate NOTE Confidence: 0.948304255 01:05:21.075 --> 01:05:23.469 them to inner neurons or excitatory neurons. NOTE Confidence: 0.948304255 01:05:23.470 --> 01:05:25.504 So that is the next step to kind of NOTE Confidence: 0.948304255 01:05:25.504 --> 01:05:27.323 make that transition and understand NOTE Confidence: 0.948304255 01:05:27.323 --> 01:05:29.627 what's the relationship of these two, NOTE Confidence: 0.948304255 01:05:29.630 --> 01:05:30.264 the humans. NOTE Confidence: 0.948304255 01:05:30.264 --> 01:05:32.483 So that's what we're doing right now NOTE Confidence: 0.948304255 01:05:32.483 --> 01:05:34.590 to do that and I'm excited to have NOTE Confidence: 0.948304255 01:05:34.590 --> 01:05:36.150 these two patients and grateful there NOTE Confidence: 0.90374499 01:05:41.150 --> 01:05:44.732 is some evidence. Yeah. NOTE Confidence: 0.90374499 01:05:44.732 --> 01:05:46.420 So I think that's. NOTE Confidence: 0.90374499 01:05:46.420 --> 01:05:48.332 So to work that you did a number NOTE Confidence: 0.90374499 01:05:48.332 --> 01:05:50.367 of years ago that was published in NOTE Confidence: 0.90374499 01:05:50.367 --> 01:05:52.291 Neuron and then work that Thomas NOTE Confidence: 0.90374499 01:05:52.291 --> 01:05:54.446 Noakowski at UCSF has recently NOTE Confidence: 0.90374499 01:05:54.446 --> 01:05:57.069 done doing single cell work really NOTE Confidence: 0.90374499 01:05:57.069 --> 01:05:59.939 I think defines that there is a NOTE Confidence: 0.90374499 01:05:59.939 --> 01:06:01.619 subpopulation of the inhibitory NOTE Confidence: 0.90374499 01:06:01.619 --> 01:06:03.614 neurons that are coming from NOTE Confidence: 0.90374499 01:06:03.614 --> 01:06:05.460 the cortical ventricular zone. NOTE Confidence: 0.942998163636364 01:06:07.980 --> 01:06:09.744 All the studies in mice don't NOTE Confidence: 0.942998163636364 01:06:09.744 --> 01:06:11.260 seem to have supported that. NOTE Confidence: 0.942998163636364 01:06:11.260 --> 01:06:12.860 That's at least my feeling from it you. NOTE Confidence: 0.942998163636364 01:06:12.860 --> 01:06:13.820 Yeah, but I I didn't see yet. NOTE Confidence: 0.6285699 01:06:16.920 --> 01:06:20.760 Maybe, yes Marks. Yeah. Yeah. NOTE Confidence: 0.938576485 01:06:28.600 --> 01:06:29.878 Yeah. So I think that's right. NOTE Confidence: 0.938576485 01:06:29.880 --> 01:06:31.665 And I do think that there are NOTE Confidence: 0.938576485 01:06:31.665 --> 01:06:33.045 those cells that are coming NOTE Confidence: 0.938576485 01:06:33.045 --> 01:06:35.104 from there and by studying these NOTE Confidence: 0.938576485 01:06:35.104 --> 01:06:36.328 ipsc's and differentiating NOTE Confidence: 0.938576485 01:06:36.328 --> 01:06:37.960 them along different lines, NOTE Confidence: 0.938576485 01:06:37.960 --> 01:06:40.120 we should be able to get at these answers. NOTE Confidence: 0.938576485 01:06:40.120 --> 01:06:41.040 But I don't know now NOTE Confidence: 0.957026046666667 01:06:44.040 --> 01:06:46.720 any other questions? All right. NOTE Confidence: 0.957026046666667 01:06:46.720 --> 01:06:47.995 Well, thank you very much.