| First Author | Pringa E | Year | 2001 |
| Journal | J Biol Chem | Volume | 276 |
| Issue | 22 | Pages | 19617-23 |
| PubMed ID | 11274149 | Mgi Jnum | J:213909 |
| Mgi Id | MGI:5586805 | Doi | 10.1074/jbc.M100192200 |
| Citation | Pringa E, et al. (2001) Interaction of the ring finger-related U-box motif of a nuclear dot protein with ubiquitin-conjugating enzymes. J Biol Chem 276(22):19617-23 |
| abstractText | The U-box domain has been suggested to be a modified RING finger motif where the metal-coordinating cysteines and histidines have been replaced with other amino acids. Known U-box-containing proteins have been implicated in the ubiquitin/proteasome system. In a search for proteins interacting with the ubiquitin-conjugating enzyme UbcM4/UbcH7, we have identified a novel U-box containing protein, termed UIP5, that is exclusively found in the nucleus as part of a nuclear dot-like structure. Interaction between UbcM4 and UIP5 was observed in vivo and in vitro with bacterially expressed proteins. In addition to UbcM4, several other ubiquitin-conjugating enzymes (E2s) that share the same sequence within the L1 loop bind to UIP5. Mutational analysis showed that the U-box, like the RING finger in other proteins, forms the physical basis for the interaction with E2 enzymes. Further support for the structural similarity between U-box and RING finger comes from the observation that, in both cases, the same regions within the UbcM4 molecule are required for interaction. Our results establish at the molecular level a link between the U-box and the ubiquitin conjugating system and strongly suggest that proteins containing U-box domains are functionally closely related to RING finger proteins. |
