Muscle: Stem and Progenitor Cells in Adults

Muscle cells are specialized adult cells in the body that can contract. These cells are composed of contractile filaments known as actin and myosin that are acted upon by several molecular motors and slide against each other to execute a contractile motion. There are three major types of muscle cells in our body: skeletal muscle, smooth muscle, and cardiac muscle. All three types of muscle arise from the mesoderm, one of the three embryonic germinal layers that form during development.

Within the mesoderm, their origins are slightly different. Skeletal muscle cells are formed by the differentiation and fusion of committed progenitor cells known as myoblasts into large multinucleated myofibers. Cardiac muscle, on the other hand, is formed from a region of progenitor cells that are committed ...