Dexras1 mediates glucocorticoid-associated adipgenesis and diet-induced obesity

The Solomon H. Snyder Department of Neuroscience and Departments of Psychiatry and Behavioral Sciences and Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 12/2013; 110(51). DOI: 10.1073/pnas.1320454110
Source: PubMed


Adipogenesis, the conversion of precursor cells into adipocytes, is associated with obesity and is mediated by glucocorticoids acting via hitherto poorly characterized mechanisms. Dexras1 is a small G protein of the Ras family discovered on the basis of its marked induction by the synthetic glucocorticoid dexamethasone. We show that Dexras1 mediates adipogenesis and diet-induced obesity. Adipogenic differentiation of 3T3-L1 cells is abolished with Dexras1 depletion, whereas overexpression of Dexras1 elicits adipogenesis. Adipogenesis is markedly reduced in mouse embryonic fibroblasts from Dexras1-deleted mice, whereas adiposity and diet-induced weight gain are diminished in the mutant mice.

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