David Geffen School of Medicine at UCLA

UCLA Neurology
P.O. Box 951769, GONDA 2309
Los Angeles, CA 90095-1769
Tel: (310) 794-1186
Email: jrexach@mednet.ucla.edu

UCLA Memory Clinic
Clinic Appts: (310) 794-1195 {Memory Evaluation}
Clinic Fax: (310) 794-7491


Neurology and Neurobehavioral Genetics.



Rexach Lab

ADRC - Biomarker Core

Research Interests

New therapeutic targets are needed for neurodegenerative disease including Alzheimer’s and related dementias. The immune system includes many of the most successful therapeutic targets in medicine. My research lab seeks to uncover mechanism by which glia and immune factors influence disease pathology in dementia to inform novel therapeutic strategies. We integrate single cell and tissue transcriptomics, epigenetic profiling, human genetics, and stem cell-based experimental models to identify neuroimmune regulators of dementia. A major focus of our current work is the interplay of glial immune signaling and neuronal dysfunction in dementia, including the role of interferon-mediated immune suppression in disease pathology.

In addition to this basic research, I am an attending at the UCLA Neurogenetics clinic where we apply advanced genomics technologies to the molecular diagnosis of adult-onset genetic diseases, including inherited neurodegenerative disorders.

Education and Degrees

1999-2003 -- B.A. Biology (Magna Cum Laude), B.A. Chemistry (Magma Cum Laude), Cornell University, Ithaca, NY

2003-2005, 2010-2012 -- Doctorate in Medicine (M.D.), David Geffen School of Medicine at UCLA, Los Angeles, CA

2005-2010 -- Ph.D., Neuroscience, University of California Los Angeles, Los Angeles, CA

2005-2010 -- Visiting Scholar in Chemistry; Specialty in Chemical Biology, California Institute of Technology, Pasadena, CA

2012-2013 -- Internship in Medicine, Cedars Sinai Medical Center, Los Angeles, CA

2013-2016 -- Residency in Neurology, University of California Los Angeles, Los Angeles, CA

2016-2018 -- Fellowship in Neurogenetics; Specialty in Neurobehavioral Genetics, University of California Los Angeles, Los Angeles, CA

Board Certifications

California Medical License (active)

Board Certified by American Board of Psychiatry and Neurology (active)


Rexach JE*, Ngo K*, Hane L, Petty LE, Perlman S, Valera JM, Deignan JL, Mao Y, Aker M, Posey JE, Jhangiani SN, Coban-Akdemir ZH, Boerwinkle E, Muzny D, Nelson AB, Hassin-Baer S, Poke G, Neas K, Geschwind MD, Grody WW, Gibbs R, Geschwind DH, Lupski JR, Below JE, Nelson SF, Fogel BL (2019). A Diagnostic Ceiling for Exome Sequencing in Cerebellar Ataxia and Related Neurological Disorders. Human Mutation. 2019 Nov 6

Xao C, M Binkley E, Rexach J, Knight-Johnson A, Khemani P, Fogel BL, Das S, M Stone E, Gomez CM. A family with spinocerebellar ataxia and retinitis pigmentosa attributed to an ELOVL4 mutation. Neurol Genet. 2019 Sep 23;5(5):e357.

Rexach JE, Swarup V, Chang T, Geschwind DH. Dementia risk genes engage gene networks poised to tune the immune response towards chronic inflammatory states. April 2019 bioRxiv. 597542. In Review.

Rexach JE, Lee H, Martinez-Agosto JA, Nemeth AH, Fogel BH (2019). Clinical Application of Next Generation Sequencing to the Practice of Neurology. Lancet Neurology. 18 (5), 492-503.

Swarup V*, Hinz FI*, Rexach JE, Noguchi K, Toyoshiba H, Oda A, Hirai K,, Sarkar A, Seyfried NT, IFGC, Grossman M, Van Deerlin VM, Trojanowski JQ, Lah JL, Levey AL, Kondou S, Geschwind DH. Identification of evolutionarily conserved gene networks that mediate neurodegeneration. Nature Medicine. 2018 Dec 3; 25: 152-164.

Wang AC, Jensen EH, Rexach JE, Vinters HV, Hsieh-Wilson, LC. Loss of O-GlcNAc glycosylation in forebrain excitatory neurons induces neurodegeneration. Proc Natl Acad Sci. 2016 Dec 27;113(52): 15120-15125.

Trikamji B, Rexach JE, Mishra SK. A case of spinocerebellar ataxia with a reversible splenium lesion due to malnutrition and vitamin deficiency. Journal of Clinical Neuromuscular Disease. 2015; 17(2):95-7.

Clark PM*, Rexach JE*, Hsieh-Wilson LC. Visualization of O-GlcNAc glycosylation stoichiometry and dynamics using resolvable poly(ethylene glycol) mass tags. Current protocols in chemical biology. 2013; 5(4):281-302.

Rexach JE*, Clark PM*, Mason DE, Neve RL, Peters EC, Hsieh-Wilson LC. Dynamic O-GlcNAc modification regulates CREB-mediated gene expression and memory formation. Nature Chemical Biology. 2012; 8(3):253-61.

Rexach JE, Rogers CJ, Yu SH, Tao J, Sun YE, Hsieh-Wilson LC. Quantification of O-glycosylation stoichiometry and dynamics using resolvable mass tags. Nature Chemical Biology. 2010; 6(9):645-51.

Rexach JE*, Clark PM*, Hsieh-Wilson LC. Chemical approaches to understanding O-GlcNAc glycosylation in the brain. Nature Chemical Biology. 2008; 4(2):97-106.

Khidekel N, Ficarro SB, Clark PM, Bryan MC, Swaney DL, Rexach JE, Sun YE, Coon JJ, Peters EC, Hsieh-Wilson LC. Probing the dynamics of O-GlcNAc glycosylation in the brain using quantitative proteomics. Nature Chemical Biology. 2007; 3(6):339-48.

Bredy TW, Wu H, Crego C, Zellhoefer JE, Sun YE, Barad M. Histone modifications around individual BDNF gene promoters in prefrontal cortex are associated with extinction of conditioned fear. Learning & Memory. 2007; 14(4):268-76.

* Co-first author