MEX is a testis-specific E3 ubiquitin ligase that promotes death receptor-induced apoptosis.

ABSTRACT: In the present study, we report the identification and characterization of MEX (MEKK1-related protein X), a protein with homology to MEKK1 that is expressed uniquely in the testis. MEX is comprises four putative zinc-binding domains including an N-terminal SWIM (SWI2/SNF2 and MuDR) domain of unknown function and two RING (really interesting new gene) fingers separated by a ZZ zinc finger domain. Biochemical analyses revealed that MEX is self-ubiquitinated and targeted for degradation through the proteasome pathway. MEX can act as an E3, Ub (ubiquitin) ligase, through the E2, Ub-conjugating enzymes UbcH5a, UbcH5c or UbcH6. A region of MEX that contains the RING fingers and the ZZ zinc finger was required for interaction with UbcH5a and MEX self-association, whereas the SWIM domain was criti

SUBMITTER: Nishito Y 

PROVIDER: S-EPMC1482824 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature