Adult skeletal muscle harbours tissue specific stem cell population called satellite cells that are essential for postnatal muscle growth and repair. All satellite cells express the transcription factor Pax7 and a subset also expresses the homologous gene Pax3. Pax and Pax7 are also expressed in emerging embryonic muscle precursors. Recent studies have shown that satellite cells originate in the embryonic dermomyotome, however their developmental regulation throughout embryogenesis and the molecular control of their activation and proliferation in the adult remains unclear.