DEPTOR cell-autonomously promotes adipogenesis and associates with obesity

An understanding of the mechanisms regulating white adipose tissue (WAT) formation is key for developing of new tools to treat obesity and its related diseases. Here, we identify DEPTOR as a positive regulator of adipogenesis whose expression is associated with obesity. In a polygenic mouse model of obesity/leanness, Deptor is part of the Fob3a QTL linked to obesity and we fine that Deptor is the highest priority candidate gene regulating WAT accumulation in this model. Using a doxycycline-inducible mouse model for Deptor overexpression, we confirmed that Deptor promotes WAT expansion in vivo. DEPTOR expression is elevated in WAT of obese humans and strongly correlates with the degree of obesity. We show that DEPTOR is induced during adipogenesis and that its overexpression cell-autonomously promotes, while its suppression blocks, adipogenesis. DEPTOR positively regulates adipogenesis by promoting the activity of the pro-adipogenic factors Akt/PKB and PPAR-gamma. These results establish DEPTOR as a physiological regulator of adipogenesis and provide new insights into the molecular mechanisms controlling WAT formation. 2 groups of F2 mice for opossing genotype at Fob3a QTL (FF versus VV) - parental strains of the F2 cross were the Fat line and congenic V-line; 5 biological replications per group; reference for Fat line: Horvat S. et al. (2000) MAMMALIAN GENOME 11(1): 2-7