2a7l
Structure of the human hypothetical ubiquitin-conjugating enzyme, LOC55284Structure of the human hypothetical ubiquitin-conjugating enzyme, LOC55284
Structural highlights
FunctionUBE2W_HUMAN Accepts ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. Catalyzes monoubiquitination. Involved in degradation of misfolded chaperone substrates by mediating monoubiquitination of STUB1/CHIP, leading to recruitment of ATXN3 to monoubiquitinated STUB1/CHIP, and restriction of the length of ubiquitin chain attached to STUB1/CHIP substrates by ATXN3. After UV irradiation, but not after mitomycin-C (MMC) treatment, acts as a specific E2 ubiquitin-conjugating enzyme for the Fanconi anemia complex by associating with E3 ubiquitin-protein ligase FANCL and catalyzing monoubiquitination of FANCD2, a key step in the DNA damage pathway. In vitro catalyzes 'Lys-11'-linked polyubiquitination. Transfers ubiquitin in complex with RING/U-box type E3s that do not have active site cysteine residues to form thioester bonds with ubiquitin, and preferentially ubiquitinates the N-terminus of substrates, such as ATXN3, STUB1 and SUMO2.[1] [2] [3] [4] [5] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedHere we describe a systematic structure-function analysis of the human ubiquitin (Ub) E2 conjugating proteins, consisting of the determination of 15 new high-resolution three-dimensional structures of E2 catalytic domains, and autoubiquitylation assays for 26 Ub-loading E2s screened against a panel of nine different HECT (homologous to E6-AP carboxyl terminus) E3 ligase domains. Integration of our structural and biochemical data revealed several E2 surface properties associated with Ub chain building activity; (1) net positive or neutral E2 charge, (2) an "acidic trough" located near the catalytic Cys, surrounded by an extensive basic region, and (3) similarity to the previously described HECT binding signature in UBE2L3 (UbcH7). Mass spectrometry was used to characterize the autoubiquitylation products of a number of functional E2-HECT pairs, and demonstrated that HECT domains from different subfamilies catalyze the formation of very different types of Ub chains, largely independent of the E2 in the reaction. Our data set represents the first comprehensive analysis of E2-HECT E3 interactions, and thus provides a framework for better understanding the molecular mechanisms of ubiquitylation. A human ubiquitin conjugating enzyme (E2)-HECT E3 ligase structure-function screen.,Sheng Y, Hong JH, Doherty R, Srikumar T, Shloush J, Avvakumov GV, Walker JR, Xue S, Neculai D, Wan JW, Kim SK, Arrowsmith CH, Raught B, Dhe-Paganon S Mol Cell Proteomics. 2012 Aug;11(8):329-41. Epub 2012 Apr 10. PMID:22496338[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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