Muscle stem cells colonize a niche located between the plasma membrane of the muscle cell and the surrounding basal lamina. These niches contain muscle stem cells from which both muscle cells and new stem cells are generated, even in newborn babies.
New research has shown that mouse muscle progenitor cells lacking components of the Notch signaling pathway cannot colonize their niche. Instead the muscle progenitor cells locate in tissue between the muscle fibers and cause a weakening of the muscles.
Researchers also found the Notch signaling pathway to have a second function in muscle development, that of preventing the differentiation of stem cells into muscle cells through suppression of the muscle developmental factor MyoD. This function seems to ensure there will always be a pool of stem cells for muscle repair and regeneration.
Adapted from the Delbrück Center for Molecular Medicine -