Jian Xu, PhD

Education & Training:
Bsc. Genetics, Fudan University, Shanghai, China (2000)
PhD. Molecular Biology, Fudan University, Shanghai, China (2005)

Research interest: My research focuses on translational work examining the role of STriatal Enriched Protein tyrosine phosphatase (STEP) in neuropsychiatric disorders, including Alzheimer’s disease (AD) and schizophrenia (SZ).

Selected publications:

1. Peer-reviewed articles

Xu J, Kurup P, Baguley TD, Foscue E, Ellman JA, Nairn AC, Lombroso PJ (2015) Inhibition of the tyrosine phosphatase STEP61 restores BDNF expression and reverses motor and cognitive deficits in phencyclidine-treated mice.
Cell Mol Life Sci doi:10.1007/s00018-015-2057-1. [Epub ahead of print]

Jang SS, Royston SE, Xu J, Cavaretta JP, Vest MO, Lee KY, Lee S, Jeong HG, Lombroso PJ, Chung HJ (2015) Regulation of STEP61 and tyrosine-phosphorylation of NMDA and AMPA receptors during homeostatic synaptic plasticity. Mol Brain 8:55.

Xu J, Kurup P, Azkona G, Baguley TD, Saavedra A, Nairn AC, Ellman JA, Pérez-Navarro E, Lombroso PJ (2015) Down-regulation of BDNF in cell and animal models increases striatal-enriched protein tyrosine phosphatase 61 (STEP61 ) levels.
J Neurochem doi: 10.1111/jnc.13295. [Epub ahead of print]

Xu J, Kurup P, Foscue E, Lombroso PJ (2015) Striatal-enriched protein tyrosine phosphatase regulates the PTPα/Fyn signaling pathway. J Neurochem 134:629-641.

Kurup PK, Xu J, Videira RA, Ononenyi C, Baltazar G, Lombroso PJ, Nairn AC (2015) STEP₆₁ is a substrate of the E3 ligase parkin and is upregulated in Parkinson's disease. Proc Natl Acad Sci U S A 112:1202-1207.

Xu J, Chatterjee M, Baguley TD, Brouillette J, Kurup P, Ghosh D, Kanyo J, Zhang Y, Seyb K, Ononenyi C, Foscue E, Anderson GM, Gresack J, Cuny GD, Glicksman MA, Greengard P, Lam TT, Tautz L, Nairn AC, Ellman JA, Lombroso PJ. Inhibitor of the Tyrosine Phosphatase STEP Reverses Cognitive Deficits in a Mouse Model of Alzheimer’s Disease. PLoS Biol 12:e1001923.

Gladding CM, Fan J, Zhang LY, Wang L, Xu J, Li EH, Lombroso PJ, Raymond LA (2014) Alterations in STriatal-Enriched protein tyrosine Phosphatase expression, activation, and downstream signaling in early and late stages of the YAC128 Huntington's disease mouse model. J Neurochem 130:145-159.

Darcq E, Hamida SB, Wu S, Phamluong K, Kharazia V, Xu J, Lombroso P, Ron D (2014) Inhibition of striatal-enriched tyrosine phosphatase 61 in the dorsomedial striatum is sufficient to increased ethanol consumption. J Neurochem 129:1024-1034.

Dabrowska J, Hazra R, Guo JD, Li C, Dewitt S, Xu J, Lombroso PJ, Rainnie DG (2013) Striatal-Enriched Protein Tyrosine Phosphatase-STEPs Toward Understanding Chronic Stress-Induced Activation of Corticotrophin Releasing Factor Neurons in the Rat Bed Nucleus of the Stria Terminalis. Biol Psychiatry 74:817-826.

Xu J, Kurup P, Nairn AC, Lombroso PJ (2012) Striatal-enriched protein tyrosine phosphatase in Alzheimer's disease. Adv Pharmacol 64:303-325.

Carty NC, Xu J, Kurup P, Brouillette J, Goebel-Goody SM, Austin DR, Yuan P, Chen G, Correa PR, Haroutunian V, Pittenger C, Lombroso PJ (2012) The tyrosine phosphatase STEP: Implications in schizophrenia and the molecular mechanism underlying antipsychotic medications. Transl Psychiatry 2:e137.

Xu J, Kurup P, Bartos JA, Patriarchi T, Hell JW, Lombroso PJ (2012) STriatal-enriched protein tyrosine phosphatase (STEP) regulates Pyk2 activity. J Biol Chem 287:20942-20956.

Sergienko E¹, Xu J¹, Liu WH, Dahl R, Critton DA, Su Y, Brown BT, Chan X, Yang L, Bobkova EV, Vasile S, Yuan H, Rascon J, Colayco S, Sidique S, Cosford ND, Chung TD, Mustelin T, Page R, Lombroso PJ, Tautz L (2012) Inhibition of hematopoietic protein tyrosine phosphatase augments and prolongs ERK1/2 and p38 activation. ACS Chem Biol 7(2):367-377.(¹equal contribution)

Gladding CM, Sepers MD, Xu J, Zhang LY, Milnerwood AJ, Lombroso PJ, Raymond LA (2012) Calpain and Striatal-Enriched Protein Tyrosine Phosphatase (STEP) Activation Contribute to Extrasynaptic NMDA Receptor Localization in a Huntington's Disease Mouse Model. Hum Mol Genet 21:3739-3752.

Zhang Y, Kurup P, Xu J, Anderson GM, Greengard P, Nairn AC, Lombroso PJ (2011) Reduced levels of the tyrosine phosphatase STEP block β amyloid-mediated GluA1/GluA2 receptor internalization. J Neurochem 119:664-672.

Saavedra A, Giralt A, Rué L, Xifró X, Xu J, Ortega Z, Lucas JJ, Lombroso PJ, Alberch J, Pérez-Navarro E (2011) Striatal-enriched protein tyrosine phosphatase expression and activity in Huntington's disease: a STEP in the resistance to excitotoxicity. J Neurosci 31(22):8150-8162.

Zhang YF, Kurup P, Xu J, Carty NC, Fernandez S, Nygaard HB, Pittenger C, Greengard P, Strittmatter SM, Nairn AC, Lombroso PJ (2010) Genetic reduction of STEP tyrosine phosphatase reverses cognitive and cellular deficits in a mouse model of Alzheimer’s disease. Proc Natl Acad Sci U S A 107:19014-19019.

Kurup P, Zhang Y, Xu J, Venkitaramani DV, Haroutunian V, Nairn A.C, Paul Greengard, Lombroso PJ (2010) Abeta-mediated NMDAR endocytosis in Alzheimer’s disease involves ubiquitination of the tyrosine phosphatase STEP. J Neurosci 30: 5948-5957.

Baum ML, Kurup P, Xu J, Lombroso PJ (2010) A STEP forward in neural function and degeneration. Commun Integr Biol 3:419-422.

Kurup P, Zhang Y, Venkitaramani DV, Xu J, Lombroso PJ (2010) The role of STEP in Alzheimer's disease. Channels 4:347-350.

Xu J, Kurup P, Zhang YF, Goebel-Goody SM, Wu PH, Hawasli AH, Baum ML, Bibb JA, Lombroso PJ (2009) Extrasynaptic NMDA receptors couple preferentially to excitotoxicity via calpain-mediated cleavage of STEP. J Neurosci 29:9330-9343.

Braithwaite SP, Xu J, Leung J, Urfer R, Nikolich K, Oksenberg D, Lombroso PJ, Shamloo M (2008) Expression and function of striatal enriched protein tyrosine phosphatase is profoundly altered in cerebral ischemia. Eur J Neurosci 27: 2444-2452.

Wang L¹, Xu J¹, Ji CN, Gu SH, Lv Y, Li S, Xu YR, Xie Y, Mao YM (2005) Cloning, expression and characterization of human glutathione S-transferase Omega 2. Int J Mol Med 16:19-27. (¹equal contribution)

Chen JX, Xu J, Zhao W, Hu GH, Cheng HP, Kang Y, Xie Y, Lu YC (2005) Characterization of human LNX, a novel ligand of Numb protein X that is downregulated in human gliomas. Int J Biochem Cell Biol 37 (11): 2273-2283.

Xu J, He T, Wang L, Wu QH, Zhao EP, Wu MQ, Dou TH, Ji CN, Gu SH, Yin K, Xie Y, Mao YM (2004) Molecular cloning and characterization of a novel human BTBD8 gene containing double BTB/POZ domains. Int J Mol Med 13:193-197.

Chen JX¹, Xu J¹, Ying K, Cao GT, Hu GH, Wang L, Luo C, Lou MQ, Mao YJ, Xie Y, Lu YC (2004) Molecular cloning and characterization of a novel human BTB domain-containing gene, BTBD10, which is down-regulated in glioma. Gene 340 (1): 61-69. (¹equal contribution)

Chen JX, Lu YC, Xu J, Huang Y, Cheng HP, Hu GH, Luo C, Lou MQ, Cao GT, Xie Y, Ying K (2004) Identification and characterization of NBEAL1, a novel human neurobeachin-like 1 protein gene from fetal brain, which is up regulated in glioma. Brain Res Mol Brain Res 125 (1-2): 147-155.

Xu J, Gu SH, Wang S, Dai JL, Ji CN, Jin YS, Qian J, Wang L, Ye X, Xie Y, Mao YM (2003) Characterization of a novel splicing variant of KLHL5, a member of the kelch protein family. Mol Biol Rep 30:239-242.

Xu J, Ji CN, Wang L, Cao YQ, Dai JL, Ye X, Zeng L, Dai JF, Wu QH, Xie Y, Mao YM (2003) Cloning and expression of a novel human C5orf12 gene, a member of the TMS_TDE family. Mol Biol Rep 30:47-52.

Xu J, Wu H, Zhang CZ, Cao JQ, Wang L, Zeng L, Ye X, Wu QH, Dai JF, Xie Y, Mao YM (2002) Identification of a novel human DDX40 gene, a new member of the DEAH-box protein family. J Hum Genet 47:681-683.

Xu J, Zhou ZX, Zeng L, Huang Y, Zhao W, Cheng C, Xu M, Xie Y, Mao YM (2001) Cloning, expression and characterization of a novel human REPS1 gene. Biochim Biophys Acta 1522:118-121.

2. Book Chapters

Kurup P, Xu J, Goebel-Goody S, Paul S, Lombroso PJ (2013) Striatal-Enriched Protein Tyrosine phosphatase (STEP). S. Choi (ed.), Encyclopedia of Signaling Molecules DOI 10.1007/978-1-4419-0461-4-630.