| Structural highlights
Function
UBC9_HUMAN Accepts the ubiquitin-like proteins SUMO1, SUMO2, SUMO3 and SUMO4 from the UBLE1A-UBLE1B E1 complex and catalyzes their covalent attachment to other proteins with the help of an E3 ligase such as RANBP2 or CBX4. Can catalyze the formation of poly-SUMO chains. Necessary for sumoylation of FOXL2 and KAT5. Essential for nuclear architecture and chromosome segregation.[1] [2] [3] [4] [5] [6] [7]
Publication Abstract from PubMed
The conjugation of ubiquitin (Ub) or ubiquitin-like proteins (UBL) to target proteins is a crucial post-translational modification that typically involves nucleophilic attack by a lysine on a charged E2 enzyme (E2~Ub/UBL), forming an oxyanion intermediate. Stabilizing this intermediate through an oxyanion hole is vital for progression of the reaction. Still, the mechanism of oxyanion stabilization in E2 enzymes remains unclear, although an asparagine residue in the conserved HPN motif of E2 enzymes was suggested to stabilize the oxyanion intermediate. Here, we study the E2 enzyme UFC1, which presents a TAK rather than an HPN motif. Crystal structures of UFC1 mutants, including one that mimics the oxyanion intermediate, combined with in vitro activity assays, suggest that UFC1 utilizes two distinct types of oxyanion holes, one that stabilizes the oxyanion intermediate during trans-ufmylation mediated by the E3 ligase, and another that stabilizes cis-driven auto-ufmylation. Our findings indicate that oxyanion stabilization is influenced by multiple factors, including C-alpha hydrogen bonding, and is adaptable, enabling different modes of action.
UFC1 reveals the multifactorial and plastic nature of oxyanion holes in E2 conjugating enzymes.,Kumar M, Banerjee S, Cohen-Kfir E, Mitelberg MB, Tiwari S, Isupov MN, Dessau M, Wiener R Nat Commun. 2025 Apr 25;16(1):3912. doi: 10.1038/s41467-025-58826-y. PMID:40280917[8]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Yasugi T, Howley PM. Identification of the structural and functional human homolog of the yeast ubiquitin conjugating enzyme UBC9. Nucleic Acids Res. 1996 Jun 1;24(11):2005-10. PMID:8668529
- ↑ Tatham MH, Jaffray E, Vaughan OA, Desterro JM, Botting CH, Naismith JH, Hay RT. Polymeric chains of SUMO-2 and SUMO-3 are conjugated to protein substrates by SAE1/SAE2 and Ubc9. J Biol Chem. 2001 Sep 21;276(38):35368-74. Epub 2001 Jul 12. PMID:11451954 doi:10.1074/jbc.M104214200
- ↑ Kim YE, Kim DY, Lee JM, Kim ST, Han TH, Ahn JH. Requirement of the coiled-coil domain of PML-RARalpha oncoprotein for localization, sumoylation, and inhibition of monocyte differentiation. Biochem Biophys Res Commun. 2005 May 13;330(3):746-54. PMID:15809060 doi:10.1016/j.bbrc.2005.03.052
- ↑ Kuo FT, Bentsi-Barnes IK, Barlow GM, Bae J, Pisarska MD. Sumoylation of forkhead L2 by Ubc9 is required for its activity as a transcriptional repressor of the Steroidogenic Acute Regulatory gene. Cell Signal. 2009 Dec;21(12):1935-44. doi: 10.1016/j.cellsig.2009.09.001. Epub, 2009 Sep 8. PMID:19744555 doi:10.1016/j.cellsig.2009.09.001
- ↑ Figueroa-Romero C, Iniguez-Lluhi JA, Stadler J, Chang CR, Arnoult D, Keller PJ, Hong Y, Blackstone C, Feldman EL. SUMOylation of the mitochondrial fission protein Drp1 occurs at multiple nonconsensus sites within the B domain and is linked to its activity cycle. FASEB J. 2009 Nov;23(11):3917-27. doi: 10.1096/fj.09-136630. Epub 2009 Jul 28. PMID:19638400 doi:10.1096/fj.09-136630
- ↑ Capili AD, Lima CD. Structure and analysis of a complex between SUMO and Ubc9 illustrates features of a conserved E2-Ubl interaction. J Mol Biol. 2007 Jun 8;369(3):608-18. Epub 2007 Apr 6. PMID:17466333 doi:10.1016/j.jmb.2007.04.006
- ↑ Sekiyama N, Arita K, Ikeda Y, Hashiguchi K, Ariyoshi M, Tochio H, Saitoh H, Shirakawa M. Structural basis for regulation of poly-SUMO chain by a SUMO-like domain of Nip45. Proteins. 2009 Dec 4. PMID:20077568 doi:10.1002/prot.22667
- ↑ Kumar M, Banerjee S, Cohen-Kfir E, Mitelberg MB, Tiwari S, Isupov MN, Dessau M, Wiener R. UFC1 reveals the multifactorial and plastic nature of oxyanion holes in E2 conjugating enzymes. Nat Commun. 2025 Apr 25;16(1):3912. PMID:40280917 doi:10.1038/s41467-025-58826-y
|
