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6ww3
From Proteopedia
Crystal structure of HERC2 ZZ domain in complex with SUMO1 tail
Structural highlights
DiseaseSUMO1_HUMAN Defects in SUMO1 are the cause of non-syndromic orofacial cleft type 10 (OFC10) [MIM:613705; also called non-syndromic cleft lip with or without cleft palate 10. OFC10 is a birth defect consisting of cleft lips with or without cleft palate. Cleft lips are associated with cleft palate in two-third of cases. A cleft lip can occur on one or both sides and range in severity from a simple notch in the upper lip to a complete opening in the lip extending into the floor of the nostril and involving the upper gum. Note=A chromosomal aberation involving SUMO1 is the cause of OFC10. Translocation t(2;8)(q33.1;q24.3). The breakpoint occurred in the SUMO1 gene and resulted in haploinsufficiency confirmed by protein assays.[1] FunctionSUMO1_HUMAN Ubiquitin-like protein that can be covalently attached to proteins as a monomer or a lysine-linked polymer. Covalent attachment via an isopeptide bond to its substrates requires prior activation by the E1 complex SAE1-SAE2 and linkage to the E2 enzyme UBE2I, and can be promoted by E3 ligases such as PIAS1-4, RANBP2 or CBX4. This post-translational modification on lysine residues of proteins plays a crucial role in a number of cellular processes such as nuclear transport, DNA replication and repair, mitosis and signal transduction. Involved for instance in targeting RANGAP1 to the nuclear pore complex protein RANBP2. Polymeric SUMO1 chains are also susceptible to polyubiquitination which functions as a signal for proteasomal degradation of modified proteins. May also regulate a network of genes involved in palate development.[2] [3] [4] [5] HERC2_HUMAN E3 ubiquitin-protein ligase that regulates ubiquitin-dependent retention of repair proteins on damaged chromosomes. Recruited to sites of DNA damage in response to ionizing radiation (IR) and facilitates the assembly of UBE2N and RNF8 promoting DNA damage-induced formation of 'Lys-63'-linked ubiquitin chains. Acts as a mediator of binding specificity between UBE2N and RNF8. Involved in the maintenance of RNF168 levels. E3 ubiquitin-protein ligase that promotes the ubiquitination and proteasomal degradation of XPA which influences the circadian oscillation of DNA excision repair activity.[6] [7] [8] Publication Abstract from PubMedHuman ubiquitin ligase HERC2, a component of the DNA repair machinery, has been linked to neurological diseases and cancer. Here, we show that the ZZ domain of HERC2 (HERC2ZZ) binds to histone H3 tail and tolerates posttranslational modifications commonly present in H3. The crystal structure of the HERC2ZZ:H3 complex provides the molecular basis for this interaction and highlights a critical role of the negatively charged site of HERC2ZZ in capturing of A1 of H3. NMR, mutagenesis, and fluorescence data reveal that HERC2ZZ binds to H3 and the N-terminal tail of SUMO1, a previously reported ligand of HERC2ZZ, with comparable affinities. Like H3, the N-terminal tail of SUMO1 occupies the same negatively charged site of HERC2ZZ in the crystal structure of the complex, although in contrast to H3 it adopts an alpha-helical conformation. Our data suggest that HERC2ZZ may play a role in mediating the association of HERC2 with chromatin. Structural Insight into Binding of the ZZ Domain of HERC2 to Histone H3 and SUMO1.,Liu J, Xue Z, Zhang Y, Vann KR, Shi X, Kutateladze TG Structure. 2020 Jul 23. pii: S0969-2126(20)30236-7. doi:, 10.1016/j.str.2020.07.003. PMID:32726574[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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