title: E2F7, a novel E2F featuring DP-independent repression of a subset of E2F-regulated genes.
abstract: The E2F family of transcription factors play an essential role in the regulation of cell cycle progression. In a screen for E2F-regulated genes we identified a novel E2F family member, E2F7. Like the recently identified E2F-like proteins of Arabidopsis, E2F7 has two DNA binding domains and binds to the E2F DNA binding consensus site independently of DP co-factors. Consistent with being an E2F target gene, we found that the expression of E2F7 is cell cycle regulated. Ectopic expression of E2F7 results in suppression of E2F target genes and accumulation of cells in G1. Furthermore, E2F7 associates with E2F-regulated promoters in vivo, and this association increases in S phase. Interestingly, however, E2F7 binds only a subset of E2F-dependent promoters in vivo, and in agreement with this, inhibition of E2F7 expression results in specific derepression of these promoters. Taken together, these data demonstrate that E2F7 is a unique repressor of a subset of E2F target genes whose products are required for cell cycle progression.
authors.affiliation: European Institute of Oncology, Department of Experimental Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Di Stefano
authors.forename: Michael Rugaard
authors.initials: MR
authors.lastname: Jensen
authors.forename: Kristian
authors.initials: K
authors.lastname: Helin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D017931:DNA Primers; D004268:DNA-Binding Proteins; D019281:Dimerization; D050684:E2F Transcription Factors; D050702:E2F7 Transcription Factor; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006367:HeLa Cells; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: D018797:Cell Cycle Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050702:E2F7 Transcription Factor; C481054:E2F7 protein, human; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D008156:Luciferases