2mt6
From Proteopedia
Solution structure of the human ubiquitin conjugating enzyme Ube2w
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] Publication Abstract from PubMedUbiquitination of the alphaN-terminus of protein substrates has been reported sporadically since the early 1980s. However, the identity of an enzyme responsible for this unique ubiquitin (Ub) modification has only recently been elucidated. We show the Ub-conjugating enzyme (E2) Ube2w uses a unique mechanism to facilitate the specific ubiquitination of the alpha-amino group of its substrates that involves recognition of backbone atoms of intrinsically disordered N termini. We present the NMR-based solution ensemble of full-length Ube2w that reveals a structural architecture unlike that of any other E2 in which its C terminus is partly disordered and flexible to accommodate variable substrate N termini. Flexibility of the substrate is critical for recognition by Ube2w, and either point mutations in or the removal of the flexible C terminus of Ube2w inhibits substrate binding and modification. Mechanistic insights reported here provide guiding principles for future efforts to define the N-terminal ubiquitome in cells. Intrinsic disorder drives N-terminal ubiquitination by Ube2w.,Vittal V, Shi L, Wenzel DM, Scaglione KM, Duncan ED, Basrur V, Elenitoba-Johnson KS, Baker D, Paulson HL, Brzovic PS, Klevit RE Nat Chem Biol. 2014 Dec 1. doi: 10.1038/nchembio.1700. PMID:25436519[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Homo sapiens | Large Structures | Brzovic PS | Klevit RE | Shi L | Vittal V | Wenzel DM