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Loss of Atg12, but not Atg5, in pro-opiomelanocortin neurons exacerbates diet-induced obesity.

ABSTRACT: The autophagy-related proteins ATG12 and ATG5 form a covalent complex essential for autophagy. Here, we demonstrate that ATG12 has distinct functions from ATG5 in pro-opiomelanocortin (POMC)-expressing neurons. Upon high-fat diet (HFD) consumption, mice lacking Atg12 in POMC-positive neurons exhibit accelerated weight gain, adiposity, and glucose intolerance, which is associated with increased food intake, reduced ambulation, and decreased LEP/leptin sensitivity. Importantly, although genetic deletion of either Atg12 or Atg5 renders POMC neurons autophagy-deficient, mice lacking Atg5 in POMC neurons do not exhibit these phenotypes. Hence, we propose nonautophagic functions for ATG12 in POMC neurons that counteract excessive weight gain in response to HFD consumption.

SUBMITTER: Malhotra R

PROVIDER: S-EPMC4502780 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Loss of Atg12, but not Atg5, in pro-opiomelanocortin neurons exacerbates diet-induced obesity.

Malhotra Ritu R Warne James P JP Salas Eduardo E Xu Allison W AW Debnath Jayanta J

Autophagy 20150101 1

The autophagy-related proteins ATG12 and ATG5 form a covalent complex essential for autophagy. Here, we demonstrate that ATG12 has distinct functions from ATG5 in pro-opiomelanocortin (POMC)-expressing neurons. Upon high-fat diet (HFD) consumption, mice lacking Atg12 in POMC-positive neurons exhibit accelerated weight gain, adiposity, and glucose intolerance, which is associated with increased food intake, reduced ambulation, and decreased LEP/leptin sensitivity. Importantly, although genetic de ...[more]

PMID: 25585051

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