5154 Regulation Of T2D Genes In Human Adipocytes

Abstract

Abstract Disclosure: Q. Zhang: None. Type 2 diabetes (T2D) is a chronic disease that affects 415 million people around the world and was the fourth leading cause of death (2015). Insulin resistance (IR), one of the major pathophysiological mechanisms that characterize T2D, is defined as the state in which cells, tissues, or organisms no longer respond appropriately to endogenous or exogenous insulin. We have generated detailed transcriptomes and chromatin state maps from the isolated adipocytes of insulin sensitive (IS) and insulin resistant (IR) human subjects. Mapping IR/IS differentially enriched H3K27ac peaks onto T2D GWAS SNPs suggested several loci as noncoding regulatory elements (REs) of human IR. We focused on the IRS1 gene, a known T2D related locus that encodes a critical protein in the insulin signaling cascade. We developed a CRISPRi-based assay that enabled us to determine which noncoding regulatory elements are required for normal IRS1 expression in human adipocytes. Our data indicate that many IR/IS differentially regulated H3K27ac peaks are critical regulatory elements for IRS1 transcription, although we did not observe that peaks that were increased in the IS state had a larger effect, as predicted. Overall, we have developed a CRISPRi-based screening system for noncoding elements in human adipocytes, which can be deployed to study many different loci related to metabolic disease. Presentation: 6/2/2024