4e54
From Proteopedia
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== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/DDB1_HUMAN DDB1_HUMAN] Required for DNA repair. Binds to DDB2 to form the UV-damaged DNA-binding protein complex (the UV-DDB complex). The UV-DDB complex may recognize UV-induced DNA damage and recruit proteins of the nucleotide excision repair pathway (the NER pathway) to initiate DNA repair. The UV-DDB complex preferentially binds to cyclobutane pyrimidine dimers (CPD), 6-4 photoproducts (6-4 PP), apurinic sites and short mismatches. Also appears to function as a component of numerous distinct DCX (DDB1-CUL4-X-box) E3 ubiquitin-protein ligase complexes which mediate the ubiquitination and subsequent proteasomal degradation of target proteins. The functional specificity of the DCX E3 ubiquitin-protein ligase complex is determined by the variable substrate recognition component recruited by DDB1. DCX(DDB2) (also known as DDB1-CUL4-ROC1, CUL4-DDB-ROC1 and CUL4-DDB-RBX1) may ubiquitinate histone H2A, histone H3 and histone H4 at sites of UV-induced DNA damage. The ubiquitination of histones may facilitate their removal from the nucleosome and promote subsequent DNA repair. DCX(DDB2) also ubiquitinates XPC, which may enhance DNA-binding by XPC and promote NER. DCX(DTL) plays a role in PCNA-dependent polyubiquitination of CDT1 and MDM2-dependent ubiquitination of TP53 in response to radiation-induced DNA damage and during DNA replication. DCX(ERCC8) (the CSA complex) plays a role in transcription-coupled repair (TCR). May also play a role in ubiquitination of CDKN1B/p27kip when associated with CUL4 and SKP2.<ref>PMID:12732143</ref> <ref>PMID:15448697</ref> <ref>PMID:14739464</ref> <ref>PMID:15882621</ref> <ref>PMID:16260596</ref> <ref>PMID:16482215</ref> <ref>PMID:17079684</ref> <ref>PMID:16407242</ref> <ref>PMID:16407252</ref> <ref>PMID:16678110</ref> <ref>PMID:16940174</ref> <ref>PMID:17041588</ref> <ref>PMID:16473935</ref> <ref>PMID:18593899</ref> <ref>PMID:18381890</ref> <ref>PMID:18332868</ref> | [https://www.uniprot.org/uniprot/DDB1_HUMAN DDB1_HUMAN] Required for DNA repair. Binds to DDB2 to form the UV-damaged DNA-binding protein complex (the UV-DDB complex). The UV-DDB complex may recognize UV-induced DNA damage and recruit proteins of the nucleotide excision repair pathway (the NER pathway) to initiate DNA repair. The UV-DDB complex preferentially binds to cyclobutane pyrimidine dimers (CPD), 6-4 photoproducts (6-4 PP), apurinic sites and short mismatches. Also appears to function as a component of numerous distinct DCX (DDB1-CUL4-X-box) E3 ubiquitin-protein ligase complexes which mediate the ubiquitination and subsequent proteasomal degradation of target proteins. The functional specificity of the DCX E3 ubiquitin-protein ligase complex is determined by the variable substrate recognition component recruited by DDB1. DCX(DDB2) (also known as DDB1-CUL4-ROC1, CUL4-DDB-ROC1 and CUL4-DDB-RBX1) may ubiquitinate histone H2A, histone H3 and histone H4 at sites of UV-induced DNA damage. The ubiquitination of histones may facilitate their removal from the nucleosome and promote subsequent DNA repair. DCX(DDB2) also ubiquitinates XPC, which may enhance DNA-binding by XPC and promote NER. DCX(DTL) plays a role in PCNA-dependent polyubiquitination of CDT1 and MDM2-dependent ubiquitination of TP53 in response to radiation-induced DNA damage and during DNA replication. DCX(ERCC8) (the CSA complex) plays a role in transcription-coupled repair (TCR). May also play a role in ubiquitination of CDKN1B/p27kip when associated with CUL4 and SKP2.<ref>PMID:12732143</ref> <ref>PMID:15448697</ref> <ref>PMID:14739464</ref> <ref>PMID:15882621</ref> <ref>PMID:16260596</ref> <ref>PMID:16482215</ref> <ref>PMID:17079684</ref> <ref>PMID:16407242</ref> <ref>PMID:16407252</ref> <ref>PMID:16678110</ref> <ref>PMID:16940174</ref> <ref>PMID:17041588</ref> <ref>PMID:16473935</ref> <ref>PMID:18593899</ref> <ref>PMID:18381890</ref> <ref>PMID:18332868</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | UV light-induced photoproducts are recognized and removed by the nucleotide-excision repair (NER) pathway. In humans, the UV-damaged DNA-binding protein (UV-DDB) is part of a ubiquitin E3 ligase complex (DDB1-CUL4A(DDB2)) that initiates NER by recognizing damaged chromatin with concomitant ubiquitination of core histones at the lesion. We report the X-ray crystal structure of the human UV-DDB in a complex with damaged DNA and show that the N-terminal domain of DDB2 makes critical contacts with two molecules of DNA, driving N-terminal-domain folding and promoting UV-DDB dimerization. The functional significance of the dimeric UV-DDB [(DDB1-DDB2)(2)], in a complex with damaged DNA, is validated by electron microscopy, atomic force microscopy, solution biophysical, and functional analyses. We propose that the binding of UV-damaged DNA results in conformational changes in the N-terminal domain of DDB2, inducing helical folding in the context of the bound DNA and inducing dimerization as a function of nucleotide binding. The temporal and spatial interplay between domain ordering and dimerization provides an elegant molecular rationale for the unprecedented binding affinities and selectivities exhibited by UV-DDB for UV-damaged DNA. Modeling the DDB1-CUL4A(DDB2) complex according to the dimeric UV-DDB-AP24 architecture results in a mechanistically consistent alignment of the E3 ligase bound to a nucleosome harboring damaged DNA. Our findings provide unique structural and conformational insights into the molecular architecture of the DDB1-CUL4A(DDB2) E3 ligase, with significant implications for the regulation and overall organization of the proteins responsible for initiation of NER in the context of chromatin and for the consequent maintenance of genomic integrity. | ||
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| + | Damaged DNA induced UV-damaged DNA-binding protein (UV-DDB) dimerization and its roles in chromatinized DNA repair.,Yeh JI, Levine AS, Du S, Chinte U, Ghodke H, Wang H, Shi H, Hsieh CL, Conway JF, Van Houten B, Rapic-Otrin V Proc Natl Acad Sci U S A. 2012 Jul 20. PMID:22822215<ref>PMID:22822215</ref> | ||
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| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 4e54" style="background-color:#fffaf0;"></div> | ||
==See Also== | ==See Also== | ||
Current revision
Damaged DNA induced UV-damaged DNA-binding protein (UV-DDB) dimerization and its roles in chromatinized DNA repair
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