Journal
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Volume 499, Issue 3, Pages 493-498Publisher
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.bbrc.2018.03.176
Keywords
AMPK; FOXO; Mul1; Starvation; Skeletal muscle; Autophagy
Categories
Ask authors/readers for more resources
AMP-activated protein kinase (AMPK) is a critical enzyme in conditions of cellular energy deficit such as exercise, hypoxia or nutritional stress. AMPK is well known to regulate protein degradation pathways notably through FOXO-related axis. In this study, we investigated the implication of AMPK activation in FOXO3 expression and stability in skeletal muscle primary myotubes. First, time course and dose response studies revealed optimal AICAR treatment duration and dose in skeletal muscle cells. Then, experiments with cycloheximide treatment of primary myotubes highlighted that AICAR infusion extends FOXO3 protein half-life. Our results also showed that AICAR treatment or nutrient depletion increases FOXO3 expression in primary myotubes and the expression of the mitochondrial E3 ligase Mull involved in mitochondrial turnover (mitophagy). In AMPK KO cells, nutrient depletion failed to alter the level of some FOXO3-dependent atrophic genes, including LC3B, BNIP3, and the mitochondrial E3 ligase Mul1, but not the expression of other genes (i.e. FOXO1, Gabarapl1, MAFbx, MuRF1). In summary, our data highlight that AMPK stabilizes FOXO3 and suggest a role in the first initiation step of mitochondrial segregation in muscle cells. (C) 2018 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available