Combinatorial control of muscle development by basic helix-loop-helix and MADS-box transcription factors.
Members of the MyoD family of muscle-specific basic helix-loop-helix (bHLH) proteins function within a genetic pathway to control skeletal muscle development. Mutational analyses of these factors suggested that their DNA binding domains mediated interaction with a coregulator required for activation of muscle-specific transcription. Members of the myocyte enhancer binding factor 2 (MEF2) family of MADS-box proteins are expressed at high levels in muscle and neural cells and at lower levels in several other cell types. MEF2 factors are unable to activate muscle gene expression alone, but they potentiate the transcriptional activity of myogenic bHLH proteins. This potentiation appears to be mediated by direct interactions between the DNA binding domains of these different types of transcription factors. Biochemical and genetic evidence suggests that MEF2 factors are the coregulators for myogenic bHLH proteins. The presence of MEF2 and cell-specific bHLH proteins in other cell types raises the possibility that these proteins may also cooperate to regulate other programs of cell-specific gene expression. We present a model to account for such cooperative interactions.
Molkentin
J D
JD
Hamon Center for Basic Cancer Research, University of Texas, Southwestern Medical Center at Dallas 75235-9148, USA.
Olson
E N
EN
D000595:Amino Acid Sequence; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins; D018507:Gene Expression Regulation, Developmental; D018257:Helix-Loop-Helix Motifs; D064326:MEF2 Transcription Factors; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000166:cytology / Q000196:embryology*; D018006:Myogenic Regulatory Factors / Q000235:genetics / Q000378:metabolism*; D018008:Myogenin / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D051792:Basic Helix-Loop-Helix Proteins; D004247:DNA; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D064326:MEF2 Transcription Factors; D018006:Myogenic Regulatory Factors; D018008:Myogenin; D014157:Transcription Factors; C499409:Mef2 protein, Drosophila