p53 tumour suppressor family (IPR002117)

Short name: p53_tumour_suppressor

Overlapping homologous superfamilies

Family relationships


The p53 tumour suppressor [PMID: 2046748, PMID: 2142001, PMID: 2142762, PMID: 2137806, PMID: 1639769] is a protein found in increased amounts in a wide variety of transformed cells. It is also detectable in many proliferating non-transformed cells, but it is undetectable or present at low levels in resting cells. It is frequently mutated or inactivated in many types of cancer. p53 seems to act as a tumour suppressor in some, but probably not all, tumour types. p53 has been implicated in cell cycle regulation, particularly in the monitoring of genomic DNA integrity prior to replication; for this reason it has been dubbed `guardian of the genome'.

p53 is a sequence-specific DNA-binding protein and transcription factor. The structure of p53 comprises 4 domains: an N-terminal transactivation domain; a central DNA-binding domain; an oligomerisation domain; and a C-terminal, basic, regulatory domain [PMID: 7796267, PMID: 8023159]. The structure of the oligomerisation domain consists of a dimer of dimers, each dimer consisting of 2 anti-parallel alpha-helices and an anti-parallel beta-sheet. The sheets lie on opposite sides of the tetramer and the helices form an unusual 4-helix bundle [PMID: 7796267, PMID: 8023159]. While the majority of p53 mutations found in human cancers are located in the DNA-binding domain, some are also found in the oligomerisation domain.

This entry also includes the p53 family members p63 [PMID: 9315105], p73 [PMID: 11932750] and transcription factor cep-1 [PMID: 11696333].

GO terms

Biological Process

GO:0006915 apoptotic process
GO:0006355 regulation of transcription, DNA-templated

Molecular Function

GO:0003677 DNA binding
GO:0003700 DNA-binding transcription factor activity

Cellular Component

GO:0005634 nucleus

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns