Identification of a damaged-DNA binding domain of the XPA protein.
The XPA (xeroderma pigmentosum group A) protein is a zinc metalloprotein consisting of 273 amino acids which binds preferentially to UV- or chemical carcinogen-damaged DNA, suggesting that it is involved in the recognition of several types of DNA damage during nucleotide excision repair processes. Here we identify a DNA binding domain of the XPA protein. The region of the XPA protein responsible for preferential binding to DNA damaged by UV or cis-diammine-dichloroplatinum(II) (cisplatin) is contained within a truncated derivative of the XPA protein, MF122, consisting of 122 amino acids and containing a C4 type zinc finger motif. CD (circular dichroism) measurements of the MF122 protein showed that it has a helix-rich secondary structure, suggesting that it is a discretely folded, functional mini-domain. The MF122 protein should be useful for structural investigation of the XPA protein and of its interaction with damaged DNA.
Kuraoka
I
I
Institute for Molecular and Cellular Biology, Osaka University, Japan.
Morita
E H
EH
Saijo
M
M
Matsuda
T
T
Morikawa
K
K
Shirakawa
M
M
Tanaka
K
K
D001483:Base Sequence; D001665:Binding Sites; D015139:Blotting, Southern; D015153:Blotting, Western; D002942:Circular Dichroism; D004249:DNA Damage; D017931:DNA Primers; D004260:DNA Repair; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis; D011485:Protein Binding; D017433:Protein Structure, Secondary; D011836:Radiation Tolerance / Q000235:genetics; D014983:Xeroderma Pigmentosum / Q000235:genetics*; D051760:Xeroderma Pigmentosum Group A Protein; D016335:Zinc Fingers
D017931:DNA Primers; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D010446:Peptide Fragments; C497314:XPA protein, human; D051760:Xeroderma Pigmentosum Group A Protein