Deletion of RBM20 exon 9 impairs skeletal muscle growth and satellite cell function in pigs.

Maintaining healthy skeletal tissue is essential for overall well-being and quality of life. Skeletal muscle plays a key role in this process, yet models for studying its detailed function are limited. While RNA-binding motif protein 20 (RBM20) is primarily associated with dilated cardiomyopathy (DCM), its role in skeletal muscle remains largely unexplored. This study investigates RBM20 function in skeletal muscle using an RBM20 exon 9 deletion pig model (RBM20E9D). The deletion of exon 9 resulted in loosely arranged muscle fibers, large inter-fiber gaps, and irregular organization, leading to impaired muscle growth and development. Analysis of skeletal muscle satellite cells revealed significantly reduced proliferation, diminished myotube formation in vitro, and disrupted sarcomere structure due to exon 9 deletion. Given the critical role of satellite cell proliferation and differentiation in muscle repair, RBM20E9D pigs offer a novel model for studying the mechanisms underlying skeletal muscle injury, repair, and growth.