p53
p53 (tumour protein p53, encoded by the TP53 gene) is a multifunctional transcription factor and tumour suppressor. It responds to cellular stress by inducing cell cycle arrest, DNA repair or apoptosis, and is also known as cellular tumour antigen p53 or LFS1. Browse Assay Genie's current range of p53 research reagents below, or read on for the biology behind the target.
p53 is a multifunctional transcription factor that induces cell cycle arrest, DNA repair or apoptosis upon binding to its target DNA sequence. It acts as a tumour suppressor in many tumour types, driving growth arrest or apoptosis depending on the physiological circumstances and cell type. It negatively regulates cell division by controlling expression of a set of genes required for that process, including an inhibitor of cyclin-dependent kinases. In response to DNA damage it also prevents CDK7 kinase activity when associated with the CAK complex, halting cell cycle progression.
Apoptosis induction appears to be mediated by stimulation of BAX and FAS antigen expression, or by repression of Bcl-2 expression. Its pro-apoptotic activity is activated through interaction with PPP1R13B/ASPP1 or TP53BP2/ASPP2, and inhibited when PPP1R13L/iASPP displaces that interaction. Together with mitochondrial PPIF, p53 contributes to oxidative stress-induced necrosis, a function largely independent of transcription. It induces transcription of lincRNA-p21 and lincRNA-Mkln1, is implicated in Notch signalling cross-over, and regulates the circadian clock by repressing CLOCK-BMAL1-mediated activation of PER2.
The p53 gene encodes a protein with transcriptional activation, DNA binding and oligomerisation domains, and belongs to the p53 family. The protein is found in the nucleus, including PML bodies, as well as the cytoplasm, endoplasmic reticulum, mitochondrial matrix and centrosome. Mutations in TP53 are associated with a variety of human cancers, including hereditary cancers such as Li-Fraumeni syndrome. Alternative splicing, alternate promoters and alternate translation initiation give rise to multiple isoforms: isoform 2 enhances isoform 1 transactivation at some promoters, isoform 4 suppresses it, and isoform 7 inhibits isoform 1-mediated apoptosis.
Mutations in TP53 are associated with a variety of human cancers, making p53 central to studies of tumour suppression.
p53 promotes apoptosis via BAX, FAS and Bcl-2 regulation, and contributes to oxidative stress-induced necrosis with mitochondrial PPIF.
p53 induces cell cycle arrest and DNA repair, and blocks CDK7 activity in the CAK complex after DNA damage.
Mutations in the p53 gene underlie hereditary cancers such as Li-Fraumeni syndrome, linking it to inherited cancer predisposition research.
p53 is a transcription factor that responds to diverse cellular stresses by regulating target genes. Depending on circumstances and cell type, it induces cell cycle arrest, apoptosis, senescence, DNA repair or changes in metabolism, which underlies its role as a tumour suppressor.
The gene symbol is TP53, the HGNC name is tumour protein p53, and UniProt lists cellular tumour antigen p53. Aliases include p53 and LFS1. Alternative splicing, alternate promoters and alternate translation initiation produce multiple isoforms with differing effects on transactivation and apoptosis.
The mouse and rat both have a Tp53 ortholog. In humans, TP53 mutations are associated with many cancers, including Li-Fraumeni syndrome. Check the datasheet of any product for its validated reactivity.
Other p53 family members, p53-binding proteins and related tumour suppressor pathway targets with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P04637; product specifications from Assay Genie datasheets.