The objective of Project 2 is to characterize the involvement of MBT (malignant brain tumor domain) proteins in prefrontal cortex (PFC) and nucleus accumbens (NAc) in mediating depression- and antidepressant-like responses in animal models. MBT proteins are the best known """"""""readers""""""""-i.e., effectors-for several key methylation states of histones, including repessive histone methylation at Lys 9 of histone H3 (H3K9me2). However, virtually nothing is known about the function of MBT proteins in brain. We have found that 3 MBT proteins, L3MBTL1, L3MBTL2, and SFMBT1, are highly expressed in PFC and NAc, where they display dramatic regulation in response to several forms of chronic stress. Depressed humans show similar altered levels of some of these same MBT proteins. Moreover, mice lacking L3MBTL1 show a pro-depression-like phenotype, consistent with findings in Project 1 that downregulation of H3K9me2 increases susceptibility to chronic stress. We have generated mutant lines of the other MBT proteins and now propose the comprehensive characterization of: 1) the regulation of L3MBTL1, L3MBTL2, and SFMBT1 in our Center's battery of depression models, and 2) the behavioral phenotypes of conditional and brain region-specific knockout, or overexpression, of these three MBT proteins. We will then use our novel method, which permits the genome-wide analysis of chromatin modifications specifically within adult PFC neurons, to map the binding of MBT proteins and their key target sites of histone methylation, including H3K9me2, in PFC neurons in chronic stress models, with parallel studies performed on PFC neurons from depressed humans (Project 4). We will also study conditional knockouts of several key histone methyltransferases, including G9a (with Project 1), which catalyze the methylated histone sites read by MBT proteins, based on the hypothesis that similar phenotypes will be observed. We are particularly excited about comparing preclinical and clinical chromatin datasets through which we will construct, specifically for PFC neurons of mouse and human, a genome-wide map of """"""""epigenetic risk loci"""""""" highly relevant for depression. Together, this work provides a template for the analysis of the role played by other histone reader proteins in depression.

Public Health Relevance

Depression has a lifetime risk of ~15% for the U.S. general population, yet available antidepressant therapies are based on serendipitous discoveries over 6 decades ago, and fully treat <50% of all affected individuals. An improved understanding of the molecular basis of depression will lead to improved treatments and diagnostic tests-a high priority for the National Institutes of Health.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Specialized Center (P50)
Project #
5P50MH096890-03
Application #
8672685
Study Section
Special Emphasis Panel (ZMH1-ERB-S)
Project Start
Project End
Budget Start
2014-05-01
Budget End
2015-04-30
Support Year
3
Fiscal Year
2014
Total Cost
$277,377
Indirect Cost
Name
Icahn School of Medicine at Mount Sinai
Department
Type
DUNS #
078861598
City
New York
State
NY
Country
United States
Zip Code
10029
Monteggia, Lisa M; Heimer, Hakon; Nestler, Eric J (2018) Meeting Report: Can We Make Animal Models of Human Mental Illness? Biol Psychiatry 84:542-545
Muir, Jessie; Lorsch, Zachary S; Ramakrishnan, Charu et al. (2018) In Vivo Fiber Photometry Reveals Signature of Future Stress Susceptibility in Nucleus Accumbens. Neuropsychopharmacology 43:255-263
Hamilton, Peter J; Burek, Dominika J; Lombroso, Sonia I et al. (2018) Cell-Type-Specific Epigenetic Editing at the Fosb Gene Controls Susceptibility to Social Defeat Stress. Neuropsychopharmacology 43:272-284
Mao, Wenjie; Salzberg, Anna C; Uchigashima, Motokazu et al. (2018) Activity-Induced Regulation of Synaptic Strength through the Chromatin Reader L3mbtl1. Cell Rep 23:3209-3222
Aleyasin, Hossein; Flanigan, Meghan E; Golden, Sam A et al. (2018) Cell-Type-Specific Role of ?FosB in Nucleus Accumbens In Modulating Intermale Aggression. J Neurosci 38:5913-5924
Lorsch, Zachary S; Loh, Yong-Hwee Eddie; Purushothaman, Immanuel et al. (2018) Estrogen receptor ? drives pro-resilient transcription in mouse models of depression. Nat Commun 9:1116
Aleyasin, Hossein; Flanigan, Meghan E; Russo, Scott J (2018) Neurocircuitry of aggression and aggression seeking behavior: nose poking into brain circuitry controlling aggression. Curr Opin Neurobiol 49:184-191
Hultman, Rainbo; Ulrich, Kyle; Sachs, Benjamin D et al. (2018) Brain-wide Electrical Spatiotemporal Dynamics Encode Depression Vulnerability. Cell 173:166-180.e14
Zhang, Song; Zhang, Hongxing; Ku, Stacy M et al. (2018) Sex Differences in the Neuroadaptations of Reward-related Circuits in Response to Subchronic Variable Stress. Neuroscience 376:108-116
Kaufman, Joan; Wymbs, Nicholas F; Montalvo-Ortiz, Janitza L et al. (2018) Methylation in OTX2 and related genes, maltreatment, and depression in children. Neuropsychopharmacology 43:2204-2211

Showing the most recent 10 out of 215 publications