Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1996 Feb;132(4):657-66.
doi: 10.1083/jcb.132.4.657.

Myogenin expression, cell cycle withdrawal, and phenotypic differentiation are temporally separable events that precede cell fusion upon myogenesis

V Andrés  1 , K Walsh
Affiliations

Myogenin expression, cell cycle withdrawal, and phenotypic differentiation are temporally separable events that precede cell fusion upon myogenesis

V Andrés et al. J Cell Biol. 1996 Feb.

Abstract

During terminal differentiation of skeletal myoblasts, cells fuse to form postmitotic multinucleated myotubes that cannot reinitiate DNA synthesis. Here we investigated the temporal relationships among these events during in vitro differentiation of C2C12 myoblasts. Cells expressing myogenin, a marker for the entry of myoblasts into the differentiation pathway, were detected first during myogenesis, followed by the appearance of mononucleated cells expressing both myogenin and the cell cycle inhibitor p21. Although expression of both proteins was sustained in mitogen-restimulated myocytes, 5-bromodeoxyuridine incorporation experiments in serum-starved cultures revealed that myogenin-positive cells remained capable of replicating DNA. In contrast, subsequent expression of p21 in differentiating myoblasts correlated with the establishment of the postmitotic state. Later during myogenesis, postmitotic (p21-positive) mononucleated myoblasts activated the expression of the muscle structural protein myosin heavy chain, and then fused to form multinucleated myotubes. Thus, despite the asynchrony in the commitment to differentiation, skeletal myogenesis is a highly ordered process of temporally separable events that begins with myogenin expression, followed by p21 induction and cell cycle arrest, then phenotypic differentiation, and finally, cell fusion.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Annu Rev Physiol. 1991;53:201-16 - PubMed
    1. Cell. 1983 Aug;34(1):281-93 - PubMed
    1. Mol Cell Biol. 1991 Aug;11(8):4104-10 - PubMed
    1. Exp Cell Res. 1984 Jun;152(2):331-47 - PubMed
    1. Mol Cell Biol. 1986 May;6(5):1412-21 - PubMed

Publication types