transcription factor E2F1; E2F-1; PBR3; PRB-binding protein E2F-1; retinoblastoma-associated protein 1; RBAP-1; retinoblastoma-binding protein 3; RBBP-3 (E2F1, RBBP3)

Function

• transcription activator that binds DNA cooperatively with dp proteins through the E2 recognition site, 5'-TTTC[CG]CGC-3' found in the promoter region of a number of genes whose products are involved in cell cycle regulation or in DNA replication
• E2F1 can mediate both cell proliferation & p53-dependent apoptosis
• component of the DRTF1/E2F transcription factor complex
• the DRTF1/E2F complex functions in the control of cell-cycle progression from G1 to S phase
• forms heterodimers with DP family members
• E2F1 binds preferentially RB1 protein (cell-cycle dependent)
• E2F1 complexes bind specifically hypophosphorylated retinoblastoma protein RB1.
• during the cell cycle, RB1 becomes phosphorylated in mid-to-late G1 phase, detaches from the DRTF1/E2F complex, rendering E2F transcriptionally active
• interacts with TRRAP, which probably mediates its interaction with histone acetyltransferase complexes, leading to transcription activation
• binds TOPBP1 & EAPP
• interacts with ARID3A
• phosphorylated by CDK2 & cyclin A-CDK2 in the S-phase
• E2F1 induces p14ARF & p53 homolog p73.
• activation of p73 is required for E2F1 induced apoptosis independent of p53

Structure

belongs to the E2F/DP family

Compartment

nucleus

Pathology

• viral oncoproteins, notably E1A, T-antigen & HPV E7, are capable of sequestering RB protein, thus releasing active DRTF1/E2 complex

More general terms

• E2F
• retinoblastoma-binding protein

Database

• UniProt: http://www.uniprot.org/uniprot/Q01094.html
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:1869
• OMIM: https://mirror.omim.org/entry/189971
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=1869