First published online January 25, 2006
Development 133, 402e (2006)
© The Company of Biologists Limited
Muscling in on adult muscle development
Although the most dramatic increase in the mass of skeletal muscle occurs
after birth, research into skeletal muscle development has tended to focus on
the embryo. On p. 601,
Klein and colleagues readdress this balance by examining whether adult muscle
stem cells recapitulate the mechanisms of embryonic skeletal muscle growth.
They focused on the basic helix-group-helix transcription factor myogenin,
which is crucial for the development of embryonic skeletal muscle.
Surprisingly, they found that conditionally mutant mice that produce no
myogenin after late embryogenesis have no consistent muscular abnormalities.
At first the authors thought that myogenin might be compensated by other
myogenic factors, such as myogenic factor 6, myogenic differentiation 1 and
myogenic factor 5. But these proteins were not sufficiently upregulated in the
conditional mutants for this to be a plausible explanation. Instead, the
authors conclude that adult skeletal muscle development is independent of
myogenin, and they speculate on possible roles of the Mef2 proteins, which
invertebrates rely on for the development of embryonic muscle.
Related articles in Development:
- Loss of myogenin in postnatal life leads to normal skeletal muscle but reduced body size
- Jennifer R. Knapp, Judith K. Davie, Anita Myer, Eric Meadows, Eric N. Olson, and William H. Klein
Development 2006 133: 601-610.
[Abstract]
[Full Text]
