| First Author | Lu J | Year | 1999 |
| Journal | Proc Natl Acad Sci U S A | Volume | 96 |
| Issue | 2 | Pages | 552-7 |
| PubMed ID | 9892671 | Mgi Jnum | J:52277 |
| Mgi Id | MGI:1328714 | Doi | 10.1073/pnas.96.2.552 |
| Citation | Lu J, et al. (1999) MyoR: a muscle-restricted basic helix-loop-helix transcription factor that antagonizes the actions of MyoD. Proc Natl Acad Sci U S A 96(2):552-7 |
| abstractText | Skeletal muscle development is controlled by a family of muscle-specific basic helix-loop-helix (bHLH) transcription factors that activate muscle genes by binding E-boxes (CANNTG) as heterodimers with ubiquitous bHLH proteins, called E proteins. Myogenic bHLH factors are expressed in proliferating undifferentiated myoblasts, but they do not initiate myogenesis until myoblasts exit the cell cycle. We describe a bHLH protein, MyoR (for myogenic repressor), that is expressed in undifferentiated myoblasts in culture and is down-regulated during differentiation. MyoR is also expressed specifically in the skeletal muscle lineage between days 10.5 and 16.5 of mouse embryogenesis and down-regulated thereafter during the period of secondary myogenesis. MyoR forms heterodimers with E proteins that bind the same DNA sequence as myogenic bHLH/E protein heterodimers, but MyoR acts as a potent transcriptional repressor that blocks myogenesis and activation of E-box-dependent muscle genes. These results suggest a role for MyoR as a lineage-restricted transcriptional repressor of the muscle differentiation program. |
