1: EMBO J. 2002 Nov 1;21(21):5775-86. 

Interaction of YY1 with E2Fs, mediated by RYBP, provides a mechanism for
specificity of E2F function.

Schlisio S, Halperin T, Vidal M, Nevins JR.

Department of Molecular Genetics and Microbiology and Howard Hughes Medical
Institute, Duke University Medical Center, Durham, NC 27710, USA.

To explore mechanisms for specificity of function within the family of E2F
transcription factors, we have identified proteins that interact with individual
E2F proteins. A two-hybrid screen identified RYBP (Ring1- and YY1-binding
protein) as a protein that interacts specifically with the E2F2 and E2F3 family
members, dependent on the marked box domain in these proteins. The Cdc6 promoter
contains adjacent E2F- and YY1-binding sites, and both are required for promoter
activity. In addition, YY1 and RYBP, in combination with either E2F2 or E2F3,
can stimulate Cdc6 promoter activity synergistically, dependent on the marked
box domain of E2F3. Using chromatin immunoprecipitation assays, we show that
both E2F2 and E2F3, as well as YY1 and RYBP, associate with the Cdc6 promoter at
G(1)/S of the cell cycle. In contrast, we detect no interaction of E2F1 with the
Cdc6 promoter. We suggest that the ability of RYBP to mediate an interaction
between E2F2 or E2F3 and YY1 is an important component of Cdc6 activation and
provides a basis for specificity of E2F function.

PMID: 12411495 [PubMed - indexed for MEDLINE]


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