Metabolism-related disorders pose a major global disease burden, as the rate of obesity rises worldwide. Fat tissue is a key site of metabolic regulation, and understanding how fat cells (adipocytes) develop forms the foundation for designing effective therapeutic and intervention strategies. This proposal aimed to understand the gene regulatory network (GRN) underlying fat cell development (adipogenesis) and to which extent this GRN is modulated by transcription factor (TF) isoforms. Adipogenesis is regulated by a network of successively activated TFs. Many of these TFs exist as multiple isoforms, a handful of which are known to function divergently from their reference forms. Most functional characterization studies have been restricted to gene-level studies, largely ignoring isoforms. Because TFs function at critical steps in adipogenesis, such functionally different isoforms could determine the difference between cells that differentiate into mature fat cells and those that remain in the precursor states. This project aimed to investigate the extent to which TF isoforms are functionally different in the context of adipogenesis by conducting two screens: an in vitro screen for TF isoforms demonstrating different DNA binding specificities using a microfluidics-based assay, and an in vivo screen for isoforms that alter adipocyte differentiation using a novel droplet-based single-cell technology assay. Findings from this project were expected to improve our understanding of transcriptional mechanisms in adipogenesis and have broad implications for the role of TF isoforms in gene regulation.
