XERODERMA-PIGMENTOSUM GROUP-E BINDING-FACTOR RECOGNIZES A BROAD-SPECTRUM OF DNA-DAMAGE

Xeroderma pigmentosum complementation group E binding factor (XPE-BF) is a damaged DNA binding protein that is deficient in a subset of patients from complementation group E of xeroderma pigmentosum. The protein recognizes various forms of DNA damage including some cyclobutane pyrimidine dimers, 6-4 photoproducts, cis-diamminedichloroplatinum(II) adducts, and single-stranded DNA. We now show that it also recognizes damage induced by nitrogen mustard, N-methyl-N'-nitro-N-nitrosoguanidine, and depurination, but has no detectable affinity for DNA adducts generated by trans-diamminedichloroplatinum(II), 4-nitroquinoline-N-oxide, 8-methoxypsoralen, or enzymatically methylated cytosine and adenine. The failure to recognize 4-nitroquinoline-N-oxide and 8-methoxypsoralen adducts is consistent with previous reports that XPE cells carry out wild-type levels of repair synthesis after DNA damage by those drugs. These results demonstrate that XPE-BF is a versatile damage recognition protein, but suggest that other proteins must contribute to the recognition of DNA lesions for the human excision repair pathway.