Mature skeletal muscle is a stable tissue imposing low homeostatic demand on its stem cells, which remain in a quiescent state in their niche over time. We have shown that these long-lived resting stem cells attenuate proteotoxicity and avoid senescence through basal autophagy. This protective "clean-up" system is lost during aging, resulting in stem cell regenerative decline. Thus, autophagy is required for muscle stem cell homeostasis maintenance.

Work in the authors’ laboratories has been supported by: MINECO, Spain SAF2012-38547, SAF2015-67369-R, AFM, E-Rare/Eranet, Fundació Marató-TV3, MDA, EU-FP7 (Myoage, Optistem and Endostem) and DuchennePP-NL, to PM-C; and ISCIII, Spain (FISPS09/01267, FIS-PI13/02512, CP09/00184, PI14/01529) and CIBERNED to MM-V. L.G.-P. was supported by a Predoctoral Fellowship from Programa de Formación de Personal Investigador (Spain).