Distinct mechanisms of E2F regulation by Drosophila RBF1 and RBF2.

ABSTRACT: RBF1, a Drosophila pRB family homolog, is required for cell cycle arrest and the regulation of E2F-dependent transcription. Here, we describe the properties of RBF2, a second family member. RBF2 represses E2F transcription and is present at E2F-regulated promoters. Analysis of in vivo protein complexes reveals that RBF1 and RBF2 interact with different subsets of E2F proteins. dE2F1, a potent transcriptional activator, is regulated specifically by RBF1. In contrast, RBF2 binds exclusively to dE2F2, a form of E2F that functions as a transcriptional repressor. We find that RBF2-mediated repression requires dE2F2. More over, RBF2 and dE2F2 act synergistically to antagonize dE2F1-mediated activation, and they co-operate to block S phase progression in transgenic animals. The network of interac

SUBMITTER: Stevaux O 

PROVIDER: S-EPMC126297 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature