cell of skeletal muscle skeletal muscle satellite cell An elongated, spindle-shaped, cell that is located between the basal lamina and the plasmalemma of a muscle fiber. These cells are mostly quiescent, but upon activation they divide to produce cells that generate new muscle fibers. https://cellxgene.cziscience.com/cellguide/CL_0000594 Skeletal muscle satellite cells are not traditionally referred to as myoblasts. They are a heterogeneous population whose division, following activiation, contributes to the formation of skeletal muscle fibers and to maintenance of the skeletal muscle statelite cell population. Skeletal muscle satellite cells (SMSCs) are a type of adult stem cell that nestles on the outer surface of the myofiber, positioned between the sarcolemma (plasma membrane of the muscle cell) and peripheral basement membrane. The primary function of SMSCs lies in their capacity to facilitate the growth and repair of damaged skeletal muscle. Upon muscle injury or trauma, these normally quiescent cells activate, proliferate, and differentiate into myoblasts. These myoblasts subsequently mature and fuse to form myotubes, which ultimately help in the repair and rebuilding of muscle fibers. This response is an integral part of the skeletal muscle's ability to recover from injury and adapt to enhanced or changing physical demands, thereby maintaining and improving muscle function. Furthermore, SMSCs also contribute to hypertrophic muscle growth due to resistance exercise and endurance training, with the notable feature of their multi-nucleated nature resulting from the fusion of differentiated myoblasts. The additional nuclei support enhanced protein synthesis, thus allowing the muscle fibers to grow and strengthen in response to exercise. In aging and in diseases, the number or functionality of these cells can decrease, leading to impaired muscle regeneration and progressive muscle weakness. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) ZFA:0009272 muscle precursor cell