MiR-431 promotes differentiation and regeneration of old skeletal muscle by targeting Smad4.

ABSTRACT: The myogenic capacity of myoblasts decreases in skeletal muscle with age. In addition to environmental factors, intrinsic factors are important for maintaining the regenerative potential of muscle progenitor cells, but their identities are largely unknown. Here, comparative analysis of microRNA (miRNA) expression profiles in young and old myoblasts uncovered miR-431 as a novel miRNA showing markedly reduced abundance in aged myoblasts. Importantly, elevating miR-431 improved the myogenic capacity of old myoblasts, while inhibiting endogenous miR-431 lowered myogenesis. Bioinformatic and biochemical analyses revealed that miR-431 directly interacted with the 3' untranslated region (UTR) of Smad4 mRNA, which encodes one of the downstream effectors of TGF-β signaling. In keeping with the low

SUBMITTER: Lee KP 

PROVIDER: S-EPMC4536309 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature