A new population of stem cells, present in skeletal muscle, is identified in two papers to be published online by Nature on 21 April 2005 (Vol. 434, No. 7036). Groups led by Margaret Buckingham and Christophe Marcelle show that the cells are of prime importance in the formation of skeletal muscle in the embryo and fetus, and argue that understanding the origin of muscle cells may help in developing therapies to combat muscle disease.
Although the origin of early embryonic muscle cells is understood, far less is known about the later stages, in which progenitor cells embedded in the muscle mass continuously form new cells in the fetus, long after the early embryonic structures have disappeared. Buckingham and her team identify a cell population in mice that continues to proliferate in the trunk and limbs during development. These cells express the transcription factors Pax3 and Pax7, the absence of which causes later muscle development to fail.
Marcelle and colleagues trace lineage in the chick to show that the origin of this cell population is in a region of the embryo called the somite, and that these cells give rise to satellite cells - the committed stem cells of adult skeletal muscle. By showing that the majority, if not all, satellite cells originate in the somite, the results presented help to resolve earlier controversial data suggesting that muscle cells originate in blood.
For Advance Online Publication of Buckingham paper, click here.
For Advance Online Publication of Marcelle paper, click here.
Margaret Buckingham (Pasteur Institute, Paris, France)
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Christophe Marcelle (Universite de la Mediterranee, Marseille, France)
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Message posted by: Trevor M. D'Souza