LEVERAGING ON CELL BIOLOGY TO UNDERSTAND PARKINSONS DISEASE

Transcript

• 00:00Pietro de Chamele,
• 00:02is a real titan of
• 00:04science, and
• 00:06it's such a pleasure to
• 00:07be able
• 00:08to interact and talk
• 00:10to you, Pietro.
• 00:11Pietro,
• 00:13actually was the
• 00:15the the chief of
• 00:17the department of cell biology
• 00:19and the chief of the
• 00:20department of neuroscience, the director
• 00:22of the Kavli Institute.
• 00:24He's also Howard Hughes investigator
• 00:27and a real legend in
• 00:29the field, and it's just
• 00:31a pleasure to to have
• 00:32you here. Thank you.
• 00:49Thank you,
• 00:51Clement, for your very nice
• 00:52introduction
• 00:53and for inviting me to
• 00:55this workshop.
• 00:57So, extensive genetic studies had
• 01:00identified more than twenty genes,
• 01:03which are responsible for familiar
• 01:05form of Parkinson's disease and
• 01:06many more genes
• 01:08would increase
• 01:09disease risk. And a key
• 01:11goal is to bridge the
• 01:12gap between
• 01:13genetics and disease mechanisms toward
• 01:15therapy.
• 01:17Really, an important goal is
• 01:18to identify
• 01:20the function of all these
• 01:21genes,
• 01:22and in particular, to understand
• 01:24whether the different genes lead
• 01:25to disease through different mechanisms
• 01:27or at least in part
• 01:28by converging on the same
• 01:30pathway.
• 01:31Because if this was the
• 01:32case as indicated here,
• 01:34therapeutic approaches to target
• 01:37a process downstream
• 01:38at the point of convergence
• 01:40of the gene
• 01:41would allow to use a
• 01:43single genetic
• 01:44strategy
• 01:45to cure
• 01:46Parkinson's
• 01:47dependent on different genes.
• 01:50So,
• 01:52to address this question, we
• 01:54need cell biology.
• 01:56The understanding of disease mechanism
• 01:58is a key premise to
• 01:59precision medicine and precision neurology.
• 02:04This slide lists
• 02:07the more than twenty genes
• 02:09that cause Parkinson's disease. Actually,
• 02:11this list is now a
• 02:12little bit longer.
• 02:14And if you analyze
• 02:16the cutative or non function
• 02:18of the gene,
• 02:19three
• 02:20functions emerge:
• 02:21Mitochondrial
• 02:22function, endolysisomal
• 02:24system,
• 02:25and synaptic transmission.
• 02:27As some of the gene
• 02:28are at the core
• 02:30of,
• 02:31projects from my own lab,
• 02:32from my career, I have
• 02:33been interested in membrane dynamics
• 02:35and membrane traffic in neurons.
• 02:37Some of these proteins are
• 02:38important in these processes,
• 02:40so I thought
• 02:41to exploit my expertise in
• 02:43cell biology to help learning
• 02:45about Parkinson's. And in particular,
• 02:47I focused
• 02:48on two genes,
• 02:50synaptogenin
• 02:51one
• 02:52and VP13C.
• 02:55Synaptogenin
• 02:56one is a gene that
• 02:57we identified many years ago.
• 02:59It is a gene implicated
• 03:00in synaptic transmission, particularly in
• 03:02synaptic vesicle recycling.
• 03:05Interestingly,
• 03:06it is a functional part
• 03:08of DnaJ6,
• 03:09also called auxilin, that was
• 03:10mentioned before in the talk
• 03:12of circular,
• 03:15the MRNAs.
• 03:17We have generated a model
• 03:19of this Parkinson's disease. We
• 03:21put the mutation in mice.
• 03:23These mice have neurological defects
• 03:25that resemble the human patient.
• 03:27We have extensively characterized these
• 03:29mice. There is a generation
• 03:31of some a subset
• 03:32of the pulmonary nerve terminal,
• 03:34but we will not talk
• 03:35about this today. My talk
• 03:36today will be exclusively focused
• 03:38on VPAT13C.
• 03:41So first a work of
• 03:42introduction and background.
• 03:44This slide shows the convergence
• 03:46of the endolyzoma system
• 03:48and of the autophagematophagy
• 03:50pathway.
• 03:51The endolyzonal system is a
• 03:53complex of organelles
• 03:55through which
• 03:56material internalized for the extracellular
• 03:58medium
• 03:59is
• 04:00fluid
• 04:01is directed to lysosome for
• 04:03degradation and metabolic recycling.
• 04:06And the mitophagy,
• 04:08autophagy is the process through
• 04:09which,
• 04:13portion of the cell structure
• 04:14in the cell that undergo
• 04:15degeneration
• 04:16are encapsulated by a membrane
• 04:18and then directed to lysosome
• 04:20for degradation.
• 04:22And,
• 04:24lysosome are the point of
• 04:25conversion of this pathway.
• 04:27A key function of lysosome
• 04:29is to digest
• 04:30and recycle metabolites,
• 04:32but another important function is
• 04:34they have to protect the
• 04:35cytosol
• 04:36from substances
• 04:38which end up in lysosol
• 04:39that can be,
• 04:40damaging for the cells. So,
• 04:42leakage could result in toxic
• 04:43effect,
• 04:44activation of innate immunity because,
• 04:46for example, some pathogen can
• 04:48be internalized through the pathway,
• 04:50DNA can escape into the
• 04:51site, so they can activate
• 04:52immunity.
• 04:53And also, if you have
• 04:55leakage, the acidic environment in
• 04:57the lysosome, which is critical
• 04:58for the function, is dissipated,
• 05:00and so this creates even
• 05:02further
• 05:03defect in lysosomal function.
• 05:05Several parts of the gene
• 05:08involved,
• 05:09lysosomal protein or protein upstream
• 05:11or lysosome,
• 05:12including with BFT13C,
• 05:14which is a topic of
• 05:15my talk today.
• 05:17Other
• 05:18genes encode mitochondrial protein, in
• 05:21particular two important ones, pink
• 05:23one and parkin, which are
• 05:24involved in quality control.
• 05:27And the idea is that
• 05:28when a, when a mitochondria
• 05:29is old and damaged,
• 05:31they induce the ubiquitination
• 05:32of protein at the surface
• 05:34and, therefore, they target into,
• 05:36mitophagy and eventually to lysosome.
• 05:39If you do not have
• 05:40this protein, you can have,
• 05:42activation
• 05:43of innate immunity because the
• 05:45DNA leak into the cytosol.
• 05:46But this protein is functionally
• 05:48functional, but, and you have
• 05:50a normal mitophagy, but then
• 05:51the lysosome leaks, then this
• 05:53DNA can,
• 05:55can leak into the cytosol
• 05:56and, again, produce this toxic
• 05:58effect. So, the lysosome are
• 05:59really critically important.
• 06:01And so,
• 06:02where is VP13C?
• 06:04VP13C
• 06:05is a protein that we
• 06:06have identified
• 06:08at the surface lysosome and
• 06:10the interface between lysosome and
• 06:12the endoplasmic
• 06:13reticulum.
• 06:15And so what does it
• 06:16do? And,
• 06:20this is the schematic
• 06:21drawing of a cell that
• 06:22show the different organelles present
• 06:24in the cell. All these
• 06:25organisms are surrounded by membrane.
• 06:27And also it's important that
• 06:28they receive the lipid because
• 06:30obviously all lipids undergo turnover.
• 06:32Most lipids are synthesized in
• 06:34the plasma reticulum,
• 06:36are delivered to other organelles
• 06:37in part by a membrane
• 06:39traffic as part of the
• 06:40membrane of the circular organelle.
• 06:42But an equally important pathway
• 06:45is a protein mediated,
• 06:48transport.
• 06:49So they are taken up
• 06:50into proteins that allow them
• 06:51to travel to, to cross
• 06:53the apous environment of the
• 06:55cell. And much of this
• 06:56protein
• 06:57dependent transport occur in membrane
• 06:59contact site because endoplasmic reticulum
• 07:02make contact with all the
• 07:03different organelle of the cell.
• 07:05And there are two types
• 07:06of lipid transfer proteins. One
• 07:08class has so called shuttle
• 07:09like lipid transfer proteins. The
• 07:11proteins that have lipid binding
• 07:13module, they shuttle back and
• 07:15forth between two membranes.
• 07:17And then there is another
• 07:18class of protein that had
• 07:19been identified here at Yale.
• 07:23This is work from our
• 07:24lab in collaboration
• 07:25with Karrie Reinisch,
• 07:27a colleague in
• 07:29cell biology, structural biology,
• 07:31identified
• 07:32a new class of protein
• 07:33that function is bridging. They
• 07:35directly connect two membranes
• 07:38and they can transport lipids
• 07:39with an hydrophobic group that
• 07:43go directly from one membrane
• 07:45to another, and this protein
• 07:46functions as cariurhinase, so in
• 07:49cooperation with scramblazers.
• 07:50And VBR13c
• 07:52is a founding member of
• 07:53this lamellar bridge like protein.
• 07:56So this is DBR322 c,
• 07:58the domain structure here, the
• 08:00predicted structure by alpha fold,
• 08:02and,
• 08:03the structure is being anticipated
• 08:05and confirmed by analysis of
• 08:08some fragment by carolinetr, by
• 08:10by crystallography and cryo EM.
• 08:12This is a surface representation
• 08:14of the molecule.
• 08:16Red and blue are
• 08:18positive charges.
• 08:19Gray is hydrophobic.
• 08:21And you can see that
• 08:22there is this hydrophobic group
• 08:23that go from one membrane
• 08:25to another through which lipid
• 08:26can slide as indicated in
• 08:28this cartoon.
• 08:29BPA, there are several BPA,
• 08:31four BPA thirteen isoform
• 08:34c is the one that
• 08:35is localized in contact as
• 08:37we've seen shown between endoplasmic
• 08:39reticulum and lysosome.
• 08:41The protein is anchored to
• 08:43endoplasmic reticulum through a protein
• 08:45called VAP and bind the
• 08:47lysosome
• 08:48by interacting
• 08:49with an adapter at the
• 08:50surface or lysosome called RAP
• 08:53seven.
• 08:54And what you see here
• 08:56is now
• 08:57the VPA thirteen c in
• 08:59real cells. This is the
• 09:00lysosome, so very high magnification
• 09:02while you're looking at the
• 09:03lysosome.
• 09:03Magenta is VPA thirteen
• 09:05expressing this cell. Green is
• 09:07the lysosomal membrane. The endoplasmic
• 09:09reticulum is not shown here,
• 09:11but the cartoon here illustrates
• 09:13the organization of this molecule
• 09:15at the interface.
• 09:16And this is actually the
• 09:18real thing. This is cryo
• 09:19electron tomography
• 09:24endoplasmic reticulum. This is a
• 09:25very thin endoplasmic reticulum,
• 09:27engrained the membrane of the
• 09:28lysosome, and this is the
• 09:30reconstruction.
• 09:31And this peg here are
• 09:32the VPIAT3C
• 09:33molecule, the interface between these
• 09:35two organelles. Keep in mind
• 09:37that in this particular case,
• 09:38the protein has been overexpressed.
• 09:40There are fewer molecules like
• 09:42this in a real cell,
• 09:43in a normal cell, but
• 09:44that's where VPF that is
• 09:45c is.
• 09:48So
• 09:49as I mentioned, it's the
• 09:50Parkinson's disease gene.
• 09:53It generated
• 09:55mice, which, like VBF thirteen
• 09:57c, this might actually do
• 09:59not reproduce,
• 10:00well,
• 10:01the the human pathology. This
• 10:03is a case for many
• 10:05model system
• 10:06of neurodegenerative diseases in mice.
• 10:08They have some behavioral defect
• 10:10by relatively mild defect. However,
• 10:12if you look at cells,
• 10:13a variety of cell type,
• 10:14in particular human cell, we
• 10:16see that in fact something
• 10:17is wrong with lysosome. There
• 10:19is an increased number of
• 10:20lysosome inactivation of Tfeb, which
• 10:22is a multi transcriptional regulator
• 10:23of lysomal gene, alteration of
• 10:25lysosomal lipids, and in particular,
• 10:27an activation of signaling pathway
• 10:29of innate immunity,
• 10:31which is the pathway they
• 10:32sense, at least in in
• 10:33this was an inner cell,
• 10:35human inner cells,
• 10:37the pathway of autoimmune
• 10:39of,
• 10:40a pathway that senses
• 10:41cytosolic
• 10:42DNA in the cytosol.
• 10:44This pathway is developed evolutionarily
• 10:46to protect cells from microbial
• 10:48invasion,
• 10:49but since mitochondria are evolution
• 10:51related to pathogen, they contain
• 10:53their own DNA, leakage of
• 10:55DNA from mitochondria can activate
• 10:57this pathway. And we found
• 10:58in VPA thirteen c, hila
• 11:00cell
• 11:01that is present of mitochondrial
• 11:03DNA in the cytosol,
• 11:04so there is a constitutive
• 11:06activation of the STING pathway.
• 11:08Also,
• 11:09Vp13C
• 11:10hila cell appears to have
• 11:11lysosomal defect
• 11:13that are responsible for defective
• 11:16degradation of activated stings. So,
• 11:18there is two mechanisms through
• 11:19which this pathway gets activated.
• 11:22So, the fact that this
• 11:23pathway is activated may distinct
• 11:24the parac
• 11:25lysosome
• 11:26have a defect, are more
• 11:28fragile.
• 11:30And,
• 11:32so we wanted to test
• 11:33directly whether lysosome of VPAT13
• 11:36C knockout cells are more
• 11:37fragile.
• 11:39And we use,
• 11:40the,
• 11:41when we studied the response
• 11:42to Lomi.
• 11:44Lomi is a small peptide,
• 11:46which is frequently used in
• 11:47study of lysosomal fragility.
• 11:50There is a compound that
• 11:51is taken up into cells,
• 11:54enter in lysosome,
• 11:55and there it is metabolized
• 11:57to membranolytic,
• 12:00small molecule,
• 12:01which produce
• 12:02holes or damage the lysomal
• 12:04membrane.
• 12:05And to test,
• 12:07to analyze this,
• 12:09GBSHD in single cell amorphragile,
• 12:11we use the galactin
• 12:13III assay. This galactin
• 12:15is a, is a, is
• 12:17a lectin
• 12:18that can express in the
• 12:20cytosol. We can actually express
• 12:21fluorescent galactin,
• 12:23and the protein normally is
• 12:25diffused through the cytosol,
• 12:27under normal condition.
• 12:29But if there are lesion
• 12:31in the lysosome,
• 12:32the galactin can enter the
• 12:34lysomal membrane and since selected,
• 12:36it recognizes the glycoprotein on
• 12:38the internal surface
• 12:40of the lysomal membrane. And
• 12:42so it can be visualized
• 12:43by the appearance of green
• 12:45lysosome.
• 12:46This cell has also been
• 12:47pre incubated. This is a
• 12:48high magnification of a cell.
• 12:50It's been pre incubated with,
• 12:54with a fluorescent dye, which
• 12:55is taken up in lysosome.
• 12:57So, when the lysosome breaks,
• 12:59you will see that this
• 13:00magenta dye is lost and
• 13:02instead the green accumulate into
• 13:05the lysosome because now the
• 13:06galactin entered this damaged lysosome.
• 13:09And when we measure the
• 13:11time it takes
• 13:13for this to happen in
• 13:14a wild type or in
• 13:15a mutant lysosome,
• 13:17in VPATC,
• 13:19knockout cell. And you can
• 13:20see there is a faster
• 13:23break of the lysosome of
• 13:26knockout cells.
• 13:27So if there is this
• 13:29faster break,
• 13:31does it mean
• 13:33that the under normal condition,
• 13:34VPAT thirteen c is actually
• 13:36recruited there to help repair.
• 13:40And so,
• 13:41there are what I just
• 13:42told you that this lysosome
• 13:44are more fragile
• 13:45and a fragile, a broken
• 13:47lysosome can undergo two phase,
• 13:49can either be degraded by
• 13:50lysophagy,
• 13:51or
• 13:52the damage can be repaired.
• 13:54So, now the question was,
• 13:55do we have any evidence
• 13:56that BPH10C
• 13:58can come and repair?
• 14:00And this is something
• 14:02that was tested
• 14:04by, Xinbo Wang in the
• 14:05lab.
• 14:07So, these are cells in
• 14:08which we have expressed
• 14:09fluorescent VP13C,
• 14:12and you can see some
• 14:13VP13C
• 14:14accumulated
• 14:16a lysosome. However, relatively few
• 14:18lysosome are
• 14:20are labeled under control condition.
• 14:22However, if we damage the
• 14:24cell with lomi, induced leak
• 14:27leakage, you will see that
• 14:28there is a dramatic and
• 14:30fast recruitment of the p
• 14:31f thirteen c. And this
• 14:33is shown here. And this
• 14:34happened literally in less than
• 14:36a minute.
• 14:37After thirty seconds, you already
• 14:39did strong accumulation, and then
• 14:41it keeps going up. And
• 14:42then there is a, eventually,
• 14:44the thing is reversed.
• 14:45If this is, if this
• 14:47recruitment correlates with the ability
• 14:49of, of VPM10C to bring
• 14:51lipid to the lysosome, we
• 14:53should see also the recruitment
• 14:54of the endoplasmic reticulum and
• 14:56lysosome to create this bridge.
• 14:58And this, in fact, is
• 14:59the case.
• 15:00These are cells before the
• 15:02high magnification
• 15:03of the cell before and
• 15:05after lomi. Here, we what
• 15:08you see at left right
• 15:09is this protein VAP,
• 15:11the anchoring site on the
• 15:12arm, and the left would
• 15:14be epitaxy. You can see
• 15:15here there are only few
• 15:17lysosome positive, but after Lomi,
• 15:19many lysosome are positive, and
• 15:20you have an accumulation of
• 15:22VAP at the same site.
• 15:24This is a fibroblastic cell.
• 15:26What about cells of the
• 15:27brain? So, we wanted to
• 15:28see whether this can happen
• 15:29in cells of the brain,
• 15:30in neuron, and microglial cells.
• 15:33And we know that there
• 15:34is a lot of IP
• 15:35activity in the brain and
• 15:36in particular microglial cells.
• 15:39So, we,
• 15:41this is, oh, by the
• 15:42way, before I go on,
• 15:44I wanted to share that
• 15:45this recruitment was confirmed by
• 15:46biochemistry. It was a collaboration
• 15:48by Shawn Ferguson
• 15:49that Amanda
• 15:50Bentley, the Susanist's lab,
• 15:53uses
• 15:54a,
• 15:55a magnetic procedure
• 15:57to purify
• 15:58a lysosome with a degree
• 15:59of purity. Cells are fed
• 16:01small iron particles. Then the
• 16:03lysosome,
• 16:05you are one way long
• 16:06enough for this particle to
• 16:07go in lysosome.
• 16:09The lysosome
• 16:10are affinity,
• 16:11are purified by a magnetic
• 16:12beads, and you can see
• 16:14that after purification,
• 16:15LAP1 is there before and
• 16:16after and only after there
• 16:18is an accumulation of EP13C.
• 16:23These are microglial cells. These
• 16:25are a cell of micro
• 16:27of microglial
• 16:28lineage. This is actually before
• 16:31microglia. This is derived from
• 16:32iPS cells. These iPS cells
• 16:35have been
• 16:38gene edited
• 16:40to FUSE HALO, which is
• 16:41a protein which can be
• 16:42tagged by fluorescent compound
• 16:45in the, in the genome.
• 16:47So, this cell expressed at
• 16:48the endogenous level,
• 16:50VTR13C.
• 16:52In green are the lysosome,
• 16:53which has been loaded with
• 16:55lyso tracker, a marker of
• 16:56the lysolome lumen. In red
• 16:57is VPAT13C.
• 16:59As we add LOMA to
• 17:00the cell, there is immediate
• 17:02loss of lyso tracker because
• 17:03of rupture. This is a
• 17:05very rapid movie. So at
• 17:06the start of the movie,
• 17:07we see loss, but it's
• 17:09really one minute. But what
• 17:10you see dramatically
• 17:12is the accumulation of VPF
• 17:13thirty c at the lysosome.
• 17:15And this is shown at
• 17:16high magnification. Here, there is
• 17:17a lysosome.
• 17:18You had Lomi very rapidly.
• 17:20The grain is lost, and
• 17:22you have accumulation of EPFLT
• 17:24at the service, and by
• 17:25FIB SEM, we can reconstruct
• 17:27lysosome of cell, and this
• 17:29to give you an idea
• 17:30of how we look the
• 17:31ER accumulated
• 17:32at
• 17:33the lysome.
• 17:34So,
• 17:35I mentioned earlier that,
• 17:38CELE developed a variety of
• 17:39mechanisms to repair lysosome.
• 17:42So, how can we
• 17:44put this, what I just
• 17:45showed you, in the context
• 17:46of which is known in
• 17:47lysosome repair?
• 17:48One basic mechanism to repair
• 17:50lysosome in the recruitment of
• 17:52the eschar complex, which is
• 17:53something which is calcium dependent.
• 17:55When you release lysosome,
• 17:57calcium escape,
• 17:59recruit,
• 18:00deschar complex.
• 18:01These are molecules that form
• 18:03filament that organize in a
• 18:05spiral, and if the spiral
• 18:06caustic,
• 18:07the hole is closed with
• 18:09the generation of vesicle inside
• 18:11the lysosome.
• 18:13Another repair mechanism
• 18:15is via the recruitment of
• 18:16endoplasmic reticulum and lipid exchange
• 18:19protein
• 18:20that fine tune the composition
• 18:21of the lipids of the
• 18:22membrane. I don't have the
• 18:23time to go in detail,
• 18:25but what we discover now
• 18:26here is a mechanism to
• 18:28deliver embarked lipids. So, really,
• 18:31this is a very high
• 18:32capacity transport mechanism that allows
• 18:34the flow of lipid from
• 18:35the cytosine to the lysome.
• 18:37And what is very interesting
• 18:38in this machinery here, the
• 18:40ESCORP,
• 18:41who picks the hole, close
• 18:43the hole, but at the
• 18:43expense of consuming
• 18:45bilayer because as you generate
• 18:47an intracellular vesicle,
• 18:49you use that bilayer.
• 18:50And we find that escort,
• 18:52the VPS, the TNC are
• 18:53recruited at the same time
• 18:54as the we we we
• 18:56function in close partnership.
• 18:59So, obviously,
• 19:00the,
• 19:02Shiba Wang was very interested
• 19:03in understanding how VP13 C
• 19:05is recruited. I do not
• 19:06have time to go in
• 19:07detail. I just show you
• 19:08this working model, and this
• 19:09working model shows that
• 19:12it is the occurrence of
• 19:13partial defect in the lysoral
• 19:15membrane that is able to
• 19:17recruit and activate VPA13C.
• 19:19We found AMFIID is in
• 19:20control condition. It is an
• 19:22out inhibitor configuration
• 19:24and the presence of packaging
• 19:26defect allows the binding of
• 19:28the lymphocytic
• 19:28heathies to the membrane and
• 19:30therefore to release the,
• 19:32the protein for an auto
• 19:33inhibitory configuration.
• 19:34Finally, let me go back
• 19:36to this cartoon here. This
• 19:37I spoke about three mechanisms
• 19:39of repair, but there is
• 19:40in the final one, which
• 19:42is CASM.
• 19:43CASM is the process through
• 19:44which when the lysosome is
• 19:45damaged, there is an activation
• 19:47of the proton pump because
• 19:49the,
• 19:49the, the acidic pH is
• 19:51lost and this is compensated
• 19:53by the activation of the
• 19:55proton pump. When the proton
• 19:56pump. When the proton pump
• 19:59is activated, it induces
• 20:01the activation
• 20:02of, the lipidation machinery for
• 20:05LC3.
• 20:06LC3, the small adapter present
• 20:08in the cytosol,
• 20:09which is the recruited lipid
• 20:10data recruited to the membrane
• 20:12by activation of spasm. And
• 20:14one of the effector of
• 20:15LC3
• 20:16is LER2. So LC3
• 20:18is able is an adapter
• 20:19that is able to bind
• 20:20protein with a leer motif,
• 20:22and Sean Ferguson has found
• 20:24that a major,
• 20:26effector of LC3 at the
• 20:27surface of lysomal
• 20:29LARP2 that we well know
• 20:31is a major Parkinson's disease
• 20:33project. And it's very interesting
• 20:35that two Parkinson's disease proteins
• 20:37are implicated in this repair
• 20:39or lysosome. I should also
• 20:40mention that Sean has shown
• 20:42that the STING pathway, which
• 20:44I showed to you is
• 20:45activated by BPH13C,
• 20:47is upstream of CASM.
• 20:49So STIM can activate CASM
• 20:51and therefore can really induce
• 20:53a strong recruitment LR2. So,
• 20:55I believe it's very interesting.
• 20:56There is a relationship between
• 20:57the two pathways. We co
• 20:59expressed BPL13C
• 21:00LR2 in cells. This is
• 21:02my last slide.
• 21:03And, we have found that
• 21:04both are recruited by Lome,
• 21:07by, in response,
• 21:08both are recruited in response
• 21:10to damaging the lysosome by
• 21:11Lome, but with different kinetics.
• 21:13First comes VPAT13C,
• 21:15then as VPAT13C
• 21:17shed, there are two counts,
• 21:18and we are very interested
• 21:19together with sure to understand
• 21:20the functional relationship between these
• 21:22two proteins. Conclusion,
• 21:25the Parkinson's disease gene VPAT13C
• 21:27encode the lipid transfer protein
• 21:29expected to mediate net lipid
• 21:30transport in contact between the
• 21:32RN
• 21:33and lysosome.
• 21:35Loss of ATTC
• 21:37function due to Parkinson disease
• 21:38mutation has an impact on
• 21:40lysome member integrity
• 21:41and on lysome member repair.
• 21:43Collectively, our results strengthen evidence
• 21:46that dysfunctional the endosomal system
• 21:48can play a role in
• 21:49Parkinson's disease.
• 21:50And finally, these are my
• 21:52collaborators
• 21:53and left a member of
• 21:54my lab, Elohira Sobeys, an
• 21:56alumna, and I want to
• 21:57acknowledge in particular
• 21:58our ACP team. They are
• 22:00the member of our team,
• 22:02which has been very,
• 22:03very powerful in,
• 22:06basically motivating
• 22:07us
• 22:08to study Parkinson's disease and
• 22:10to interact with each other
• 22:12to really advance the understanding
• 22:13of Parkinson's disease.