Analysis of DNA binding by human factor xeroderma pigmentosum complementation group A (XPA) provides insight into its interactions with nucleotide excision repair substrates
| Autor: | Michelle S. Roh, Agnieszka M. Topolska-Woś, Norie Sugitani, Markus Voehler, Walter J. Chazin |
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| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
endocrine system Xeroderma pigmentosum Saccharomyces cerevisiae Proteins HMG-box DNA Repair DNA repair Mutation Missense DNA Single-Stranded Saccharomyces cerevisiae Biology 010402 general chemistry medicine.disease_cause 01 natural sciences Biochemistry 03 medical and health sciences chemistry.chemical_compound medicine Humans Protein–DNA interaction Molecular Biology Nuclear Magnetic Resonance Biomolecular Mutation Xeroderma Pigmentosum Cell Biology medicine.disease Molecular biology 0104 chemical sciences Xeroderma Pigmentosum Group A Protein DNA binding site 030104 developmental biology DNA Repair Enzymes chemistry Amino Acid Substitution Structural Homology Protein DNA Molecular Biophysics Nucleotide excision repair Protein Binding |
| Zdroj: | The Journal of biological chemistry. 292(41) |
| ISSN: | 1083-351X |
| Popis: | Xeroderma pigmentosum (XP) complementation group A (XPA) is an essential scaffolding protein in the multiprotein nucleotide excision repair (NER) machinery. The interaction of XPA with DNA is a core function of this protein; a number of mutations in the DNA-binding domain (DBD) are associated with XP disease. Although structures of the central globular domain of human XPA and data on binding of DNA substrates have been reported, the structural basis for XPA's DNA-binding activity remains unknown. X-ray crystal structures of the central globular domain of yeast XPA (Rad14) with lesion-containing DNA duplexes have provided valuable insights, but the DNA substrates used for this study do not correspond to the substrates of XPA as it functions within the NER machinery. To better understand the DNA-binding activity of human XPA in NER, we used NMR to investigate the interaction of its DBD with a range of DNA substrates. We found that XPA binds different single-stranded/double-stranded junction DNA substrates with a common surface. Comparisons of our NMR-based mapping of binding residues with the previously reported Rad14-DNA crystal structures revealed similarities and differences in substrate binding between XPA and Rad14. This includes direct evidence for DNA contacts to the residues extending C-terminally from the globular core, which are lacking in the Rad14 construct. Moreover, mutation of the XPA residue corresponding to Phe-262 in Rad14, previously reported as being critical for DNA binding, had only a moderate effect on the DNA-binding activity of XPA. The DNA-binding properties of several disease-associated mutations in the DBD were investigated. These results suggest that for XPA mutants exhibiting altered DNA-binding properties, a correlation exists between the extent of reduction in DNA-binding affinity and the severity of symptoms in XP patients. |
| Databáze: | OpenAIRE |
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