E2F1 inhibition of transcription activation by myogenic basic helix-loop-helix regulators

✍ Scribed by Jian Wang; Qian Huang; Wei Tang; Bernardo Nadal-Ginard

• Book ID: 102655876
• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 604 KB
• Volume: 62
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/(sici)1097-4644(199609)62:3<405::aid-jcb10>3.0.co;2-h

✦ Synopsis

Cellular transcription factor E2F1 is thought to regulate the expression of genes important for cell cycle progression and cell proliferation. Deregulated E2F1 expression induces S-phase entry in quiescent cells and inhibits myogenic differentiation. We show here that E2F1 inhibits the activation of gene transcription by myogenic basic helix-loop-helix proteins myoD and myogenin. Transfection assay using different deletion constructs indicates that both the DNA binding and the transactivation domains of E2F1 are required for its inhibition of myoD transcription activation. However, the retinoblastoma protein (RB) binding domain is not required. Furthermore, co-transfection with the RB, which inhibits the transcription activity of E2F1, can also repress E2F1 inhibition of myoD transactivation. These results suggest an essential role of E2F1 -mediated transcription in its inhibition of myogenesis.