1snh: Difference between revisions
No edit summary |
No edit summary |
||
Line 18: | Line 18: | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: Akutsu, H | [[Category: Akutsu, H]] | ||
[[Category: Choi, B S | [[Category: Choi, B S]] | ||
[[Category: Ikegami, T | [[Category: Ikegami, T]] | ||
[[Category: Lee, J H | [[Category: Lee, J H]] | ||
[[Category: Park, C J | [[Category: Park, C J]] | ||
[[Category: Shin, J S | [[Category: Shin, J S]] | ||
[[Category: Cpd]] | [[Category: Cpd]] | ||
[[Category: Dna]] | [[Category: Dna]] | ||
[[Category: G-t mismatch]] | [[Category: G-t mismatch]] | ||
[[Category: Major groove widening]] | [[Category: Major groove widening]] |
Revision as of 21:21, 15 January 2015
Solution structure of the DNA Decamer Duplex Containing Double TG Mismatches of Cis-syn Cyclobutane Pyrimidine DimerSolution structure of the DNA Decamer Duplex Containing Double TG Mismatches of Cis-syn Cyclobutane Pyrimidine Dimer
Structural highlights
Publication Abstract from PubMedThe cis-syn cyclobutane pyrimidine dimer (CPD) is a cytotoxic, mutagenic and carcinogenic DNA photoproduct and is repaired by the nucleotide excision repair (NER) pathway in mammalian cells. The XPC-hHR23B complex as the initiator of global genomic NER binds to sites of certain kinds of DNA damage. Although CPDs are rarely recognized by the XPC-hHR23B complex, the presence of mismatched bases opposite a CPD significantly increased the binding affinity of the XPC-hHR23B complex to the CPD. In order to decipher the properties of the DNA structures that determine the binding affinity for XPC-hHR23B to DNA, we carried out structural analyses of the various types of CPDs by NMR spectroscopy. The DNA duplex which contains a single 3' T*G wobble pair in a CPD (CPD/GA duplex) induces little conformational distortion. However, severe distortion of the helical conformation occurs when a CPD contains double T*G wobble pairs (CPD/GG duplex) even though the T residues of the CPD form stable hydrogen bonds with the opposite G residues. The helical bending angle of the CPD/GG duplex was larger than those of the CPD/GA duplex and properly matched CPD/AA duplex. The fluctuation of the backbone conformation and significant changes in the widths of the major and minor grooves at the double T*G wobble paired site were also observed in the CPD/GG duplex. These structural features were also found in a duplex that contains the (6-4) adduct, which is efficiently recognized by the XPC-hHR23B complex. Thus, we suggest that the unique structural features of the DNA double helix (that is, helical bending, flexible backbone conformation, and significant changes of the major and/or minor grooves) might be important factors in determining the binding affinity of the XPC-hHR23B complex to DNA. NMR structure of the DNA decamer duplex containing double T*G mismatches of cis-syn cyclobutane pyrimidine dimer: implications for DNA damage recognition by the XPC-hHR23B complex.,Lee JH, Park CJ, Shin JS, Ikegami T, Akutsu H, Choi BS Nucleic Acids Res. 2004 Apr 30;32(8):2474-81. Print 2004. PMID:15121904[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
|