A functional role for the p62-ERK1 axis in the control of energy homeostasis and adipogenesis.

Department of Cancer and Cell Biology, The Vontz Center for Molecular Studies, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, USA.
EMBO Reports (Impact Factor: 7.86). 02/2010; 11(3):226-32. DOI: 10.1038/embor.2010.7
Source: PubMed

ABSTRACT In vivo genetic inactivation of the signalling adapter p62 leads to mature-onset obesity and insulin resistance, which correlate with reduced energy expenditure (EE) and increased adipogenesis, without alterations in feeding or locomotor functions. Enhanced extracellular signal-regulated kinase (ERK) activity in adipose tissue from p62-knockout (p62(-/-)) mice, and differentiating fibroblasts, suggested an important role for this kinase in the metabolic alterations of p62(-/-) mice. Here, we show that genetic inactivation of ERK1 in p62(-/-) mice reverses their increased adiposity and adipogenesis, lower EE and insulin resistance. These results establish genetically that p62 is a crucial regulator of ERK1 in metabolism.

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May 27, 2014