E4F1

The zinc finger protein encoded by this gene is one of several cellular transcription factors whose DNA-binding activities are regulated through the action of adenovirus E1A. A 50-kDa amino-terminal product is generated from the full-length protein through proteolytic cleavage. The protein is differentially regulated by E1A-induced phosphorylation. The full-length gene product represses transcription from the E4 promoter in the absence of E1A, while the 50-kDa form acts as a transcriptional activator in its presence. [provided by RefSeq]

E4F1

May function as a transcriptional repressor. May also function as a ubiquitin ligase mediating ubiquitination of chromatin-associated TP53. Functions in cell survival and proliferation through control of the cell cycle. Functions in the p53 and pRB tumor suppressor pathways and regulates the cyclin CCNA2 transcription.

Identified as a cellular target of the adenoviral oncoprotein E1A, it is required for both transcriptional activation and repression of viral genes.

Cell cycle Source: UniProtKB-KW
Cell division Source: UniProtKB-KW
DNA replication Source: Ensembl
Negative regulation of transcription by RNA polymerase II Source: UniProtKB
Positive regulation of transcription by RNA polymerase II Source: GO_Central
Protein ubiquitination Source: UniProtKB-UniPathway
Regulation of cell cycle Source: UniProtKB
Regulation of cell cycle process Source: UniProtKB
Regulation of growth Source: UniProtKB-KW
Regulation of mitotic cell cycle, embryonic Source: Ensembl
Regulation of transcription by RNA polymerase II Source: GO_Central

Nucleoplasm; Cytoplasm. A small fraction is detected in the cytoplasm. Excluded from the nucleolus where it is targeted upon CDKN2A overexpression. Localizes to the mitotic spindle during embryogenesis.

Proteolytic cleavage produces a 50 kDa N-terminal peptide (p50E4F) which has a DNA-binding activity and activates transcription in presence of the adenoviral E1A protein. The major full-length protein (p120E4F) functions as a repressor of transcription.
Phosphorylated; p120E4F and p50E4F are both phosphorylated. Phosphorylation is cell cycle-dependent and differentially regulates DNA-binding activity and function of both forms.
May be sumoylated by UBE2I upon interaction with CDKN2A.