Developmental dynamics of skeletal muscle can be recapitulated in vitro from pig embryonic stem cells

Given the value of pigs as a large-animal model bridging rodents and humans, a porcine in vitro system for skeletal muscle development is a prerequisite for advancing both fundamental and translational research. Here, we establish a stepwise and high-resolution in vitro fate-map of pig skeletal muscle development from embryonic stem cells (ESCs). Single-cell analysis revealed three "myogenic states" faithfully recapitulating the conserved in vivo developmental trajectory: (1) specification of posterior presomitic mesoderm (PSM), (2) PSM patterning and somitogenesis, and (3) myogenesis from somite. Furthermore, we uncover porcine molecular signatures by identifying CDH15 and ADAM22 as markers for pig ESC-derived myogenic progenitors capable of generating multinucleated myotubes. Altogether, we present a comprehensive in vitro roadmap of pig skeletal muscle development by constructing previously uncharacterized developmental dynamics as a continuum. These findings offer a powerful resource for comparative developmental biology and translational preclinical research.