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
. 1997 Aug;17(8):4750-60.
doi: 10.1128/MCB.17.8.4750.

Muscle LIM protein promotes myogenesis by enhancing the activity of MyoD

Affiliations

Muscle LIM protein promotes myogenesis by enhancing the activity of MyoD

Y Kong et al. Mol Cell Biol. 1997 Aug.

Abstract

The muscle LIM protein (MLP) is a muscle-specific LIM-only factor that exhibits a dual subcellular localization, being present in both the nucleus and in the cytoplasm. Overexpression of MLP in C2C12 myoblasts enhances skeletal myogenesis, whereas inhibition of MLP activity blocks terminal differentiation. Thus, MLP functions as a positive developmental regulator, although the mechanism through which MLP promotes terminal differentiation events remains unknown. While examining the distinct roles associated with the nuclear and cytoplasmic forms of MLP, we found that nuclear MLP functions through a physical interaction with the muscle basic helix-loop-helix (bHLH) transcription factors MyoD, MRF4, and myogenin. This interaction is highly specific since MLP does not associate with nonmuscle bHLH proteins E12 or E47 or with the myocyte enhancer factor-2 (MEF2) protein, which acts cooperatively with the myogenic bHLH proteins to promote myogenesis. The first LIM motif in MLP and the highly conserved bHLH region of MyoD are responsible for mediating the association between these muscle-specific factors. MLP also interacts with MyoD-E47 heterodimers, leading to an increase in the DNA-binding activity associated with this active bHLH complex. Although MLP lacks a functional transcription activation domain, we propose that it serves as a cofactor for the myogenic bHLH proteins by increasing their interaction with specific DNA regulatory elements. Thus, the functional complex of MLP-MyoD-E protein reveals a novel mechanism for both initiating and maintaining the myogenic program and suggests a global strategy for how LIM-only proteins may control a variety of developmental pathways.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Mol Cell Biol. 1982 Sep;2(9):1044-51 - PubMed
    1. Genes Dev. 1996 Nov 1;10(21):2794-804 - PubMed
    1. Nature. 1984 Sep 6-11;311(5981):33-8 - PubMed
    1. Cell. 1987 Dec 24;51(6):987-1000 - PubMed
    1. Cell. 1988 Jul 1;54(1):5-16 - PubMed

Publication types

MeSH terms