Publication details
An essential function of the extreme C-terminus of MDM2 can be provided by MDMX
| Authors | |
|---|---|
| Year of publication | 2007 |
| Type | Article in Periodical |
| Magazine / Source | EMBO Journal |
| MU Faculty or unit | |
| Citation | |
| Field | Genetics and molecular biology |
| Keywords | E3; MDM2; MDMX; p53; ubiquitin |
| Description | MDM2 (HDM2) is a ubiquitin ligase that can target the p53 tumor suppressor protein for degradation. The RING domain is essential for the E3 activity of MDM2, and we show here that the extreme C-terminal tail of MDM2 is also critical for efficient E3 activity. Loss of E3 function in MDM2 mutants deleted of the C-terminal tail correlated with a failure of these mutants to oligomerize with MDM2, or with the related protein MDMX (HDMX). However, MDM2 containing point mutations within the C-terminus that inactivated E3 function retained the ability to oligomerize with the wild-type MDM2 RING domain and MDMX, and our results indicate that oligomers containing both wild-type MDM2 and a C-terminal mutant protein retain E3 function both in auto-degradation and degradation of p53. Interestingly, the E3 activity of C-terminal point mutants of MDM2 can also be supported by interaction with wild-type MDMX, suggesting that MDMX can directly contribute to E3 function. |