| Structural highlights
Function
[UB2V2_HUMAN] Has no ubiquitin ligase activity on its own. The UBE2V2/UBE2N heterodimer catalyzes the synthesis of non-canonical poly-ubiquitin chains that are linked through 'Lys-63'. This type of poly-ubiquitination does not lead to protein degradation by the proteasome. 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.[1] [2] [3] [4] [UBE2N_HUMAN] The UBE2V1-UBE2N and UBE2V2-UBE2N heterodimers catalyze the synthesis of non-canonical 'Lys-63'-linked polyubiquitin chains. This type of polyubiquitination does not lead to protein degradation by the proteasome. 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. Acts together with the E3 ligases, HLTF and SHPRH, in the 'Lys-63'-linked poly-ubiquitination of PCNA upon genotoxic stress, which is required for DNA repair. Appears to act together with E3 ligase RNF5 in the 'Lys-63'-linked polyubiquitination of JKAMP thereby regulating JKAMP function by decreasing its association with components of the proteasome and ERAD. 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 (By similarity).[5] [6] [7] [8] [9]
Publication Abstract from PubMed
Initiation of the DNA damage and innate immune responses is dependent upon the flow of chemical information through coupled protein-protein interaction networks and driven by the synthesis and recognition of Lys 63 linked polyubiquitin (polyUb) chains on adaptor proteins. The central chemical step in Lys 63-linked protein ubiquitination involves the reaction of a specific lysine on a target protein with Ub that is covalently attached as a thioester conjugate to the Ub conjugating enzyme (E2) Ubc13. The active site cysteine of Ubc13, and E2 enzymes in general, is buttressed by a flexible loop. The role of loop dynamics in catalysis was investigated by mutating the central and hinge residues to glycine. The loop dynamics were experimentally characterized through measurement of enzyme kinetics, main chain NMR relaxation, X-ray crystallographic studies, and in vivo studies in yeast. The experimental data were complemented by analysis of MD simulations of the dynamics and kinetics for the loop motion. The results show that fast pico- to nanosecond time scale active site loop fluctuations play a crucial role in regulating the catalytic activity of Ubc13 by functioning as a stochastic active site gate, which is characterized by precisely balanced rates of opening and closing. In vivo functional complementation assays in yeast demonstrate that defects within this regulatory mechanism can have profound biological consequences, given that Ubc13 is the only E2 dedicated to synthesizing Lys 63-linked polyUb chains.
Stochastic Gate Dynamics Regulate the Catalytic Activity of Ubiquitination Enzymes.,Rout MK, Hodge CD, Markin CJ, Xu X, Glover JN, Xiao W, Spyracopoulos L J Am Chem Soc. 2014 Dec 5. PMID:25423605[10]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Xiao W, Lin SL, Broomfield S, Chow BL, Wei YF. The products of the yeast MMS2 and two human homologs (hMMS2 and CROC-1) define a structurally and functionally conserved Ubc-like protein family. Nucleic Acids Res. 1998 Sep 1;26(17):3908-14. PMID:9705497
- ↑ Hofmann RM, Pickart CM. Noncanonical MMS2-encoded ubiquitin-conjugating enzyme functions in assembly of novel polyubiquitin chains for DNA repair. Cell. 1999 Mar 5;96(5):645-53. PMID:10089880
- ↑ Bothos J, Summers MK, Venere M, Scolnick DM, Halazonetis TD. The Chfr mitotic checkpoint protein functions with Ubc13-Mms2 to form Lys63-linked polyubiquitin chains. Oncogene. 2003 Oct 16;22(46):7101-7. PMID:14562038 doi:10.1038/sj.onc.1206831
- ↑ 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
- ↑ Hofmann RM, Pickart CM. Noncanonical MMS2-encoded ubiquitin-conjugating enzyme functions in assembly of novel polyubiquitin chains for DNA repair. Cell. 1999 Mar 5;96(5):645-53. PMID:10089880
- ↑ Bothos J, Summers MK, Venere M, Scolnick DM, Halazonetis TD. The Chfr mitotic checkpoint protein functions with Ubc13-Mms2 to form Lys63-linked polyubiquitin chains. Oncogene. 2003 Oct 16;22(46):7101-7. PMID:14562038 doi:10.1038/sj.onc.1206831
- ↑ Tcherpakov M, Delaunay A, Toth J, Kadoya T, Petroski MD, Ronai ZA. Regulation of endoplasmic reticulum-associated degradation by RNF5-dependent ubiquitination of JNK-associated membrane protein (JAMP). J Biol Chem. 2009 May 1;284(18):12099-109. doi: 10.1074/jbc.M808222200. Epub 2009, Mar 6. PMID:19269966 doi:10.1074/jbc.M808222200
- ↑ 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
- ↑ Pertel T, Hausmann S, Morger D, Zuger S, Guerra J, Lascano J, Reinhard C, Santoni FA, Uchil PD, Chatel L, Bisiaux A, Albert ML, Strambio-De-Castillia C, Mothes W, Pizzato M, Grutter MG, Luban J. TRIM5 is an innate immune sensor for the retrovirus capsid lattice. Nature. 2011 Apr 21;472(7343):361-5. doi: 10.1038/nature09976. PMID:21512573 doi:10.1038/nature09976
- ↑ Rout MK, Hodge CD, Markin CJ, Xu X, Glover JN, Xiao W, Spyracopoulos L. Stochastic Gate Dynamics Regulate the Catalytic Activity of Ubiquitination Enzymes. J Am Chem Soc. 2014 Dec 5. PMID:25423605 doi:http://dx.doi.org/10.1021/ja505440b
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