mir-1 coordinately regulates lysosomal v-ATPase and biogenesis to affect muscle contractility upon proteotoxic challenge during ageing

Muscle function relies on the precise architecture of dynamic contractile elements, which must be fine-tuned to maintain motility throughout life. Muscle is also highly plastic, and remodeled in response to stress, growth, neural and metabolic inputs. The evolutionarily conserved muscle microRNA, mir1, regulates distinct aspects of muscle biology during development, but whether it plays a role during ageing is unknown. Here we investigated the role of C. elegans mir-1 in muscle function in response to proteostatic stress during adulthood. mir-1 deletion results in improved mid-life muscle motility, pharyngeal pumping, and organismal longevity under conditions of polyglutamine repeat proteotoxic challenge. We identified multiple vacuolar ATPase subunits as subject to mir-1 control, and the regulatory subunit vha-13/ATP6VIA as a direct target downregulated via its 3’UTR to mediate mir-1 physiology. mir-1 further regulates nuclear localization of lysosomal biogenesis factor HLH-30/TFEB and lysosomal acidification. Our studies reveal that mir-1 coordinately regulates lysosomal v-ATPase and biogenesis to impact muscle function and health during ageing.