Antagonistic control of myofiber size and muscle protein quality control by the ubiquitin ligase UBR4 during aging

Abstract

Sarcopenia is the age-associated functional decline and atrophy of muscle fibers, and it has been proposed that it might be counteracted by inducing myofiber hypertrophy. Here, the authors show that expression levels of the ubiquitin ligase UBR4 are increased with ageing, and that whilst its genetic ablation rescues muscle atrophy, it is also associated with reduced protein quality and impaired force production in Drosophila and mouse models.