Xeroderma pigmentosum complementation group C protein (XPC) serves as a general sensor of damaged DNA.
The Xeroderma pigmentosum complementation group C protein (XPC) serves as the primary initiating factor in the global genome nucleotide excision repair pathway (GG-NER). Recent reports suggest XPC also stimulates repair of oxidative lesions by base excision repair. However, whether XPC distinguishes among various types of DNA lesions remains unclear. Although the DNA binding properties of XPC have been studied by several groups, there is a lack of consensus over whether XPC discriminates between DNA damaged by lesions associated with NER activity versus those that are not. In this study we report a high-throughput fluorescence anisotropy assay used to measure the DNA binding affinity of XPC for a panel of DNA substrates containing a range of chemical lesions in a common sequence. Our results demonstrate that while XPC displays a preference for binding damaged DNA, the identity of the lesion has little effect on the binding affinity of XPC. Moreover, XPC was equally capable of binding to DNA substrates containing lesions not repaired by GG-NER. Our results suggest XPC may act as a general sensor of damaged DNA that is capable of recognizing DNA containing lesions not repaired by NER.
Department of Biochemistry, Center for Structural Biology, Center in Molecular Toxicology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, USA.
Steven M
SM
Shell
Edward K
EK
Hawkins
Miaw-Sheue
MS
Tsai
Aye Su
AS
Hlaing
Carmelo J
CJ
Rizzo
Walter J
WJ
Chazin
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D004249:DNA Damage; D004260:DNA Repair / Q000502:physiology; D045643:DNA Repair Enzymes / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005454:Fluorescence Polarization; D057166:High-Throughput Screening Assays; D006801:Humans; D061987:Sf9 Cells; D018411:Spodoptera / Q000378:metabolism
D004268:DNA-Binding Proteins; C513287:RAD23B protein, human; C086984:XPC protein, human; D004247:DNA; D045643:DNA Repair Enzymes
Base excision repair; DNA binding; High-throughput assay; Lesion recognition; Nucleotide excision repair; XPC