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Solution Structure of the Human Ubiquitin-conjugating Enzyme Variant Uev1aSolution Structure of the Human Ubiquitin-conjugating Enzyme Variant Uev1a
Structural highlights
FunctionUB2V1_HUMAN Has no ubiquitin ligase activity on its own. The UBE2V1-UBE2N heterodimer catalyzes the synthesis of non-canonical poly-ubiquitin chains that are linked through Lys-63. This type of poly-ubiquitination activates IKK and does not seem to involve protein degradation by the proteasome. Plays a role in the activation of NF-kappa-B mediated by IL1B, TNF, TRAF6 and TRAF2. Mediates transcriptional activation of target genes. Plays a role in the control of progress through the cell cycle and differentiation. Plays a role in the error-free DNA repair pathway and contributes to the survival of cells after DNA damage. Promotes TRIM5 capsid-specific restriction activity and the UBE2V1-UBE2N heterodimer acts in concert with TRIM5 to generate 'Lys-63'-linked polyubiquitin chains which activate the MAP3K7/TAK1 complex which in turn results in the induction and expression of NF-kappa-B and MAPK-responsive inflammatory genes.[1] [2] [3] [4] [5] [6] [7] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedLys(63)-linked polyubiquitination of TRAF2 or TRAF6 is an essential step within the signal transduction cascade responsible for activation of p38, c-Jun N-terminal kinase, and the transcription factor NF-kappaB. Attachment of ubiquitin (Ub) to a TRAF, and conjugation of Ub molecules to form a polyUb chain, is catalyzed by a heterodimer composed of a catalytically active E2 (hUbc13), involved in covalent bond transfer, and hUev1a, an E2-like protein involved in substrate Ub binding. Given the key biochemical processes in which hUev1a is involved, it is important to determine the molecular basis of the catalytic mechanism for Lys(63)-linked protein ubiquitination. Nuclear magnetic resonance (NMR) spectroscopy was used to determine the structure of hUev1a and its interactions with Ub and hUbc13. A structural model for the Ub-hUev1a-hUbc13-Ub tetramer was developed to gain chemical insight into the synthesis of Lys(63)-linked Ub chains. We propose that a network of hydrogen bonds involving hUbc13-Asp(81) and Ub-Glu(64) positions Ub-Lys(63) proximal to the active site. Interestingly, restrained molecular dynamics simulations in implicit solvent indicate that deprotonation of Ub-Lys(63) does not involve a general Asp or Glu base and may occur when the amino group approaches the thioester carbonyl carbon near the Burgi-Dunitz trajectory. Structure and interactions of the ubiquitin-conjugating enzyme variant human Uev1a: implications for enzymatic synthesis of polyubiquitin chains.,Hau DD, Lewis MJ, Saltibus LF, Pastushok L, Xiao W, Spyracopoulos L Biochemistry. 2006 Aug 15;45(32):9866-77. PMID:16893187[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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