IndraLab

"HERC2 promotes USP20 degradation.|Under unperturbed condition, HERC2 ubiquitinates USP20 and promotes ubiquitination mediated proteasomal degradation of USP20, regulating the status of K48 linked polyubiquitination of CLASPIN and ensuring appropriate protein levels of CLASPIN during the S-phase."

"USP20 is regulated by HERC2 following DNA damage or replication stress.The HECT domain of WT HERC but not the catalytic inactive mutant (CA) ubiquitinated USP20 in vitro (Figure ​(Figure4G).4G). Taken together, these results suggested that HERC2 functions as an E3 ligase of USP20 and negatively regulates USP20 in unstressed cells."

"VDU1 and VDU2 could be important substrates of pVHL E3 ligase complex. Finally, we demonstrate that VDU2 can also be ubiquitinated and degraded in a pVHL-dependent manner.pVHL mediates the degradation of hVDU2 by proteasome. we have demonstrated that both VDU1 and VDU2 also bind to the β-domain of pVHL and several naturally occurring mutations in the β-domain disrupt the interaction between VDU1/VDU2 and pVHL. If pVHL is mutated either in the α-domain or β-domain, VDU1 and VDU2 would not be ubiquitinated and degraded properly. This could lead to accumulation of these two proteins in the cells. Together, our results suggest that VDU1 and VDU2 might be relevent to pVHL-related tumorigenesis."