7449 A Genome-wide CRISPR Screen Identifies Drivers of Impaired Glucose Uptake in Human Insulin Resistance

Abstract

Abstract Disclosure: N. Haider: None. Y. Lee: None. P. Yi: None. C.R. Kahn: None. Insulin resistance is a major risk factor in the development of type 2 diabetes (T2D), and metabolic syndrome. Although 25% of people within the general non-diabetic population are insulin resistant, the primary underlying cause of insulin resistance remains elusive. In this study, we have used induced pluripotent stem cells (iPSC) derived from non-diabetic humans at both ends of the insulin sensitivity spectrum, i.e., the top 20% of insulin resistance vs. the top 20% of insulin sensitive, as well as individuals with T2D to model human insulin resistance. We find that iPSCs differentiated into myoblasts (iMyos) from T2D and non-diabetic individuals in the highest quintile of insulin resistance (I-Res) show impaired insulin signaling and defective insulin-stimulated glucose uptake, as compared to iMyos from the insulin sensitive individuals (I-Sen), indicating that these cells in vitro mirror the alterations seen in vivo in a cell autonomous manner. To uncover the primary upstream drivers that contribute to the impaired glucose uptake associated with insulin resistance, we conducted a genome-wide loss-of-function screen using a CRISPR-based approach to identify genes that positively or negatively regulated glucose uptake in I-Res and T2D iMyos. Knockdown of ∼525 genes show effect to rescue the impaired glucose uptake in both I-Res and T2D iMyos, i.e., were negative regulators of glucose uptake. We hypothesized that important negative regulators of glucose uptake might be over-expressed at the protein level in I-Res and T2D iMyos and crossing the iMyos proteomics data with the CRISPR screen revealed 8 top candidates that are increased at the protein level and whose knockdown rescued glucose uptake in I-Res and T2D iMyos. These included candidates associated with cytoskeleton changes, protein kinases, transmembrane transport, mitochondrial and nuclear proteins. In summary, iPSC derived myoblasts from patients with insulin resistance and T2D mirror defects in glucose uptake observed in vivo. Combining CRISPR screening and global proteomics, we have identified important upstream regulators of insulin resistance in humans. Presentation: 6/2/2024