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总部位于加利福尼亚州圣迭戈，在中国北京设有办公室，专注于为研究需求提供多克隆和单克隆抗体、ELISA试剂盒、蛋白质和定制服务。Aviva Systems Biology生产了24,000种经过验证的多克隆抗体，并提供近20,000种ELISA试剂盒，定制实验室服务包括蛋白表达和纯化、抗体开发，以及ELISA的开发、验证和生产。Aviva Systems Biology为与独特物种和靶标相关的研究提供独特工具，研究领域包括转录因子、癌症、心血管、细胞生物学、DNA损伤和修复、表观遗传学、信号转导、细胞分化、干细胞生物学等等。
