AMPK regulates germline stem cell quiescence and integrity through an endogenous small RNA pathway

Abstract

13C. elegans larvae can undergo a global developmental arrest following the execution of a diapause-14 like state called 'dauer' in response to unfavourable growth conditions. Survival in this stage 15 surpasses the normal lifespan of reproductive animals quite dramatically, and without any apparent 16 negative impact on their reproductive fitness. During this period, the germ cells become quiescent 17 and must retain their reproductive integrity so the animal can reproduce following recovery. This 18 germline stem cell (GSC) arrest requires the activity of AMP-activated protein kinase (AMPK) 19 and in its absence the germ line undergoes hyperplasia. We show here that AMPK mutant animals 20 exhibit complete sterility after recovery from dauer, suggesting that germ cell integrity is 21 compromised during this stage in the absence of AMPK. These defects correlate with altered 22 soma communicates with the germ line to establish the appropriate epigenetic modifications 36 required to adapt to acute environmental challenges. 37