Comprehensive characterization of HNF1A-driven beta-cell heterogeneity

PROJECT ABSTRACT The heterogeneity of pancreatic β-cells has been reported in many studies, but the field still lacks a consensus about its molecular signature and disease relevance. Our recent single cell multiome analysis suggested that HNF1A is a principal driver of a T2D-associated heterogeneity among the -cells from the same individual. By leveraging single cell Patch-seq data, we also discovered that HNF1A activity is associated with lower Na+ currents in β-cells and nominated a HNF1A target, FXYD2, as the primary mitigator. Since mutations in HNF1A are known to cause early onset diabetes (MODY3), there is a strong likelihood that HNF1A plays a causal role in T2D via governing -cell heterogeneity. In fact, many literatures studied HNF1A and its mutations due to the connection to MODY3, but little is known about its role in common diabetes in the context of -cell heterogeneity. It should be noted that although our previous work has demonstrated the power of single cell multiome to study -cell heterogeneity, the data did not allow us to directly compare the HNF1Ahi and HNF1Alo -cell populations due to technical difficulties. In this project we will develop new single cell multiome integration strategy to directly survey HNF1A function in -cell heterogeneity. We will establish stem cell models to manipulate HNF1A dosage in hESC-derived -cells, which will not only provide mechanistic insights into how HNF1A mediates MODY3 and -cell heterogeneity, but also offer new opportunity to improve the functionality of hPSC-derived -like cells for therapeutical benefits. We will also develop new cell line model to allow genetic and chemical screens for the upstream regulators of HNF1A in -cells. Taken together, our project will establish a new concept linking MODY3 gene HNF1A to common diabetes in the context of -cell heterogeneity.