Valerie Morin

Abstract Myoblast fusion into multinucleated myotubes is essential for skeletal muscle development and repair, yet how tissue-scale mechanics contributes to this process remains poorly understood. Here, we show that primary myoblasts behave as an evolving active nematic system in which actomyosin-dependent stresses, extracellular-matrix (ECM) remodeling and fusion-driven myotube growth are dynamically coupled.

Abstract Myogenesis in amniotes unfolds through two consecutive waves. The primary myotube lineage is characterized by the expression of slow myosin, sometimes in combination with fast myosin, and may serve as a scaffold for the secondary lineage, which expresses exclusively fast myosin. The embryonic origin of these two lineages, their relationship, and their connection to adult muscle stem cells are unknown.