Structural highlightsFunctionUB2D2_HUMAN Accepts ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. In vitro catalyzes 'Lys-48'-linked polyubiquitination. Mediates the selective degradation of short-lived and abnormal proteins. Functions in the E6/E6-AP-induced ubiquitination of p53/TP53. Mediates ubiquitination of PEX5 and autoubiquitination of STUB1 and TRAF6. Involved in the signal-induced conjugation and subsequent degradation of NFKBIA, FBXW2-mediated GCM1 ubiquitination and degradation, MDM2-dependent degradation of p53/TP53 and the activation of MAVS in the mitochondria by DDX58/RIG-I in response to viral infection. Essential for viral activation of IRF3.[1] [2] [3] [4] [5] [6] [7] [8]
Publication Abstract from PubMed
RING-domain E3 ligases enhance transfer of ubiquitin to substrate proteins by stabilizing the RING-bound thioester-linked E2 approximately ubiquitin conjugate in a defined conformation that primes the active site for nucleophilic attack. Here we report that the monomeric RING domains from the human E3 ligases Arkadia and Ark2C bind directly to free ubiquitin with an affinity comparable to that of other dedicated ubiquitin-binding domains. Further work showed that the Ark-like RING domain and the noncovalently bound ubiquitin molecule coordinately stabilize the E2-conjugated ubiquitin (donor ubiquitin) in the 'closed' conformation. Our studies identify the RING domain of Arkadia as a ubiquitin-binding domain and provide insight into a new ubiquitin-dependent mechanism used by monomeric RING domains to activate ubiquitin transfer. This study also suggests how substrates that have been monoubiquitinated could be favored for further ubiquitination.
Secondary ubiquitin-RING docking enhances Arkadia and Ark2C E3 ligase activity.,Wright JD, Mace PD, Day CL Nat Struct Mol Biol. 2015 Dec 14. doi: 10.1038/nsmb.3142. PMID:26656854[9]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See AlsoReferences
- ↑ Gonen H, Bercovich B, Orian A, Carrano A, Takizawa C, Yamanaka K, Pagano M, Iwai K, Ciechanover A. Identification of the ubiquitin carrier proteins, E2s, involved in signal-induced conjugation and subsequent degradation of IkappaBalpha. J Biol Chem. 1999 May 21;274(21):14823-30. PMID:10329681
- ↑ Saville MK, Sparks A, Xirodimas DP, Wardrop J, Stevenson LF, Bourdon JC, Woods YL, Lane DP. Regulation of p53 by the ubiquitin-conjugating enzymes UbcH5B/C in vivo. J Biol Chem. 2004 Oct 1;279(40):42169-81. Epub 2004 Jul 26. PMID:15280377 doi:10.1074/jbc.M403362200
- ↑ Windheim M, Peggie M, Cohen P. Two different classes of E2 ubiquitin-conjugating enzymes are required for the mono-ubiquitination of proteins and elongation by polyubiquitin chains with a specific topology. Biochem J. 2008 Feb 1;409(3):723-9. PMID:18042044 doi:10.1042/BJ20071338
- ↑ Chiang MH, Chen LF, Chen H. Ubiquitin-conjugating enzyme UBE2D2 is responsible for FBXW2 (F-box and WD repeat domain containing 2)-mediated human GCM1 (glial cell missing homolog 1) ubiquitination and degradation. Biol Reprod. 2008 Nov;79(5):914-20. doi: 10.1095/biolreprod.108.071407. Epub 2008, Aug 13. PMID:18703417 doi:10.1095/biolreprod.108.071407
- ↑ Grou CP, Carvalho AF, Pinto MP, Wiese S, Piechura H, Meyer HE, Warscheid B, Sa-Miranda C, Azevedo JE. Members of the E2D (UbcH5) family mediate the ubiquitination of the conserved cysteine of Pex5p, the peroxisomal import receptor. J Biol Chem. 2008 May 23;283(21):14190-7. doi: 10.1074/jbc.M800402200. Epub 2008 , Mar 22. PMID:18359941 doi:10.1074/jbc.M800402200
- ↑ Zeng W, Xu M, Liu S, Sun L, Chen ZJ. Key role of Ubc5 and lysine-63 polyubiquitination in viral activation of IRF3. Mol Cell. 2009 Oct 23;36(2):315-25. doi: 10.1016/j.molcel.2009.09.037. PMID:19854139 doi:10.1016/j.molcel.2009.09.037
- ↑ Zeng W, Sun L, Jiang X, Chen X, Hou F, Adhikari A, Xu M, Chen ZJ. Reconstitution of the RIG-I pathway reveals a signaling role of unanchored polyubiquitin chains in innate immunity. Cell. 2010 Apr 16;141(2):315-30. doi: 10.1016/j.cell.2010.03.029. PMID:20403326 doi:10.1016/j.cell.2010.03.029
- ↑ David Y, Ziv T, Admon A, Navon A. The E2 ubiquitin conjugating enzymes direct polyubiquitination to preferred lysines. J Biol Chem. 2010 Jan 8. PMID:20061386 doi:M109.089003
- ↑ Wright JD, Mace PD, Day CL. Secondary ubiquitin-RING docking enhances Arkadia and Ark2C E3 ligase activity. Nat Struct Mol Biol. 2015 Dec 14. doi: 10.1038/nsmb.3142. PMID:26656854 doi:http://dx.doi.org/10.1038/nsmb.3142
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