Adult skeletal muscle has a remarkable ability to regenerate following myot
rauma. Because adult myofibers are terminally differentiated, the regenerat
ion of skeletal muscle is largely dependent on a small population of reside
nt cells termed satellite cells. Although this population of cells was iden
tified 40 years ago, little is known regarding the molecular phenotype or r
egulation of the satellite cell. The use of cell culture techniques and tra
nsgenic animal models has improved our understanding of this unique cell po
pulation; however, the capacity and potential of these cells remain ill-def
ined. This review will highlight the origin and unique markers of the satel
lite cell population, the regulation by growth factors, and the response to
physiological and pathological stimuli. We conclude by highlighting the po
tential therapeutic uses of satellite cells and identifying future research
goals for the study of satellite cell biology.