Acts as a tumor suppressor in many tumor types; induces growth arrest or apoptosis depending on the physiological circumstances and cell type. Involved in cell cycle regulation as a trans-activator that acts to negatively regulate cell division by controlling a set of genes required for this process. One of the activated genes is an inhibitor of cyclin-dependent kinases. Apoptosis induction seems to be mediated either by stimulation of BAX and FAS antigen expression, or by repression of Bcl-2 expression. In cooperation with mitochondrial PPIF is involved in activating oxidative stress-induced necrosis; the function is largely independent of transcription. Induces the transcription of long intergenic non-coding RNA p21 (lincRNA-p21) and lincRNA-Mkln1. LincRNA-p21 participates in TP53-dependent transcriptional repression leading to apoptosis and seem to have to effect on cell-cycle regulation. Implicated in Notch signaling cross-over. Prevents CDK7 kinase activity when associated to CAK complex in response to DNA damage, thus stopping cell cycle progression. Isoform 2 enhances the transactivation activity of isoform 1 from some but not all TP53-inducible promoters. Isoform 4 suppresses transactivation activity and impairs growth suppression mediated by isoform 1. Isoform 7 inhibits isoform 1-mediated apoptosis. Regulates the circadian clock by repressing CLOCK-ARNTL/BMAL1-mediated transcriptional activation of PER2 (PubMed:24051492).
Aviva Systems Biology總部位于加利福尼亞州圣迭戈，在中國北京設有辦公室，專注于為研究需求提供多克隆和單克隆抗體、ELISA試劑盒、蛋白質和定制服務。Aviva Systems Biology生產了24,000種經過驗證的多克隆抗體，并提供近20,000種ELISA試劑盒，定制實驗室服務包括蛋白表達和純化、抗體開發，以及ELISA的開發、驗證和生產。Aviva Systems Biology為與獨特物種和靶標相關的研究提供獨特工具，研究領域包括轉錄因子、癌癥、心血管、細胞生物學、DNA損傷和修復、表觀遺傳學、信號轉導、細胞分化、干細胞生物學等等。
