USP7 (also known as HAUSP) is an important deubiquitinating enzyme (DUB) belonging to the ubiquitin specific protease (USP) subfamily. USP7 acts as a key regulator of cellular p53 levels, strongly stabilising p53 even in the presence of an excess of the p53 targeting ubiquitin E3 ligase MDM2, and inducing p53-dependent cell growth repression and apoptosis.
It has been shown that a partial reduction of endogenous USP7 levels destabilises endogenous p53. However, nearly complete ablation of USP7 stabilises and activates p53 because USP7 is also required for the stability of endogenous MDM2, which is constitutively self-ubiquitinated and degraded in vivo. In the absence of USP7, MDM2 appears to be extremely unstable, leading to indirect p53 activation. This feedback mediated p53 stabilisation is MDM2 dependent. USP7 therefore provides an important mechanism by which p53 can be stabilized directly by deubiquitination, suggesting that it may function as a tumour suppressor in vivo through the stabilisation of p53.
應用類型
免疫原
Peptide derived from C-terminus of human USP7 protein
