Article

AMP-activated kinase links serotonergic signaling to glutamate release for regulation of feeding behavior in C. elegans.

Department of Physiology, University of California, San Francisco, San Francisco, CA 94158-2517, USA.
Cell metabolism (Impact Factor: 16.75). 07/2012; 16(1):113-21. DOI: 10.1016/j.cmet.2012.05.014
Source: PubMed

ABSTRACT Serotonergic regulation of feeding behavior has been studied intensively, both for an understanding of the basic neurocircuitry of energy balance in various organisms and as a therapeutic target for human obesity. However, its underlying molecular mechanisms remain poorly understood. Here, we show that neural serotonin signaling in C. elegans modulates feeding behavior through inhibition of AMP-activated kinase (AMPK) in interneurons expressing the C. elegans counterpart of human SIM1, a transcription factor associated with obesity. In turn, glutamatergic signaling links these interneurons to pharyngeal neurons implicated in feeding behavior. We show that AMPK-mediated regulation of glutamatergic release is conserved in rat hippocampal neurons. These findings reveal cellular and molecular mediators of serotonergic signaling.

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