Muscle repair after physiological damage relies on nuclear migration for cellular reconstruction
William Roman, Helena Pinheiro, Mafalda R. Pimentel, Jessica Segalés, Luis M. Oliveira, Esther García-Domínguez, Mari Carmen Gómez‐Cabrera, Antonio L. Serrano, Edgar R. Gomes, Pura Muñoz‐Cánoves
Abstract
Regeneration of skeletal muscle is a highly synchronized process that requires muscle stem cells (satellite cells). We found that localized injuries, as experienced through exercise, activate a myofiber self-repair mechanism that is independent of satellite cells in mice and humans. Mouse muscle injury triggers a signaling cascade involving calcium, Cdc42, and phosphokinase C that attracts myonuclei to the damaged site via microtubules and dynein. These nuclear movements accelerate sarcomere repair and locally deliver messenger RNA (mRNA) for cellular reconstruction. Myofiber self-repair is a cell-autonomous protective mechanism and represents an alternative model for understanding the restoration of muscle architecture in health and disease.