Insulin resistance (IR) is a sine qua non of Type 2 diabetes and a pathogenic factor in many other disease states. The molecular basis of IR is complex, and associated with many interweaving pathways. We have focused on nuclear mechanisms of IR, comprising the combined actions of transcription factors (TFs) and epigenomic modifiers. In the prior funding cycle we have identified several transcriptional regulators of cellular and tissue IR using advanced epigenomic strategies. For the upcoming cycle, we propose to shift to the study of human IR; specifically, the identification of transcriptional mechanisms that drive the development of IR in human adipocytes. Toward this end, we have generated chromatin state maps of primary adipocytes from insulin resistant and sensitive subjects, leading to the identification of thousands of enhancers with differential activity in IR. First, we will link these enhancers to their target genes using a novel mathematical model, and then validate a number of these predictions using CRISPRi. Next, we will assess which of these enhancers and genes show evidence of allelic imbalance, thus implying a genetic basis for their differential enrichment and predicting SNPs responsible for this effect. A massively parallel reporter assay will further implicate individual SNPs and TF motifs as candidates for drivers of IR, thus enabling the prediction of upstream regulators that bind and activate the enhancers. Finally, we will validate causal SNPs using base editing in cultured adipocytes testing their effects on target gene expression and insulin sensitivity. We will also validate candidate upstream regulators using a combination of gain- and loss-of-function approaches in vitro and in vivo. The key deliverable of this proposal will be the elucidation of the detailed transcriptional mechanisms underlying noncoding variation leading to human IR.

Public Health Relevance

It is known that transcriptional mechanisms contribute to human insulin resistance, but it is unclear how genetic and epigenetic variation affect processes that promote disease risk. We have accumulated epigenomic, transcriptomic, and genetic data from the isolated adipocytes of multiple insulin sensitive and resistant human subjects. In this proposal we will identify specific noncoding variants that predispose to insulin resistance and will decipher the genes and pathways that promote Type 2 diabetes.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK102173-07
Application #
10088438
Study Section
Molecular and Cellular Endocrinology Study Section (MCE)
Program Officer
Silva, Corinne M
Project Start
2015-04-01
Project End
2023-01-31
Budget Start
2021-02-01
Budget End
2022-01-31
Support Year
7
Fiscal Year
2021
Total Cost
Indirect Cost
Name
Beth Israel Deaconess Medical Center
Department
Type
DUNS #
071723621
City
Boston
State
MA
Country
United States
Zip Code
02215
Kong, Xingxing; Yao, Ting; Zhou, Peng et al. (2018) Brown Adipose Tissue Controls Skeletal Muscle Function via the Secretion of Myostatin. Cell Metab 28:631-643.e3
Ahmad, Rasheed; Al-Roub, Areej; Kochumon, Shihab et al. (2018) The Synergy between Palmitate and TNF-? for CCL2 Production Is Dependent on the TRIF/IRF3 Pathway: Implications for Metabolic Inflammation. J Immunol 200:3599-3611
Roh, Hyun Cheol; Tsai, Linus T Y; Shao, Mengle et al. (2018) Warming Induces Significant Reprogramming of Beige, but Not Brown, Adipocyte Cellular Identity. Cell Metab 27:1121-1137.e5
De Filippis, Elena; Li, Ting; Rosen, Evan David (2018) Exposure of adipocytes to bisphenol-A in vitro interferes with insulin action without enhancing adipogenesis. PLoS One 13:e0201122
Roh, Hyun Cheol; Tsai, Linus T-Y; Lyubetskaya, Anna et al. (2017) Simultaneous Transcriptional and Epigenomic Profiling from Specific Cell Types within Heterogeneous Tissues In Vivo. Cell Rep 18:1048-1061
Shen, Yachen; Roh, Hyun Cheol; Kumari, Manju et al. (2017) Adipocyte glucocorticoid receptor is important in lipolysis and insulin resistance due to exogenous steroids, but not insulin resistance caused by high fat feeding. Mol Metab 6:1150-1160
Campbell, John N; Macosko, Evan Z; Fenselau, Henning et al. (2017) A molecular census of arcuate hypothalamus and median eminence cell types. Nat Neurosci 20:484-496
You, Dongjoo; Nilsson, Emma; Tenen, Danielle E et al. (2017) Dnmt3a is an epigenetic mediator of adipose insulin resistance. Elife 6:
Kazak, Lawrence; Chouchani, Edward T; Lu, Gina Z et al. (2017) Genetic Depletion of Adipocyte Creatine Metabolism Inhibits Diet-Induced Thermogenesis and Drives Obesity. Cell Metab 26:660-671.e3
Rosen, E D (2016) Epigenomic and transcriptional control of insulin resistance. J Intern Med 280:443-456

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