Nucleotide excision repair (NER) is one of the major DNA repair pathways in eukaryotic cells preventing genetic abnormalities caused by DNA damage. NER removes a wide set of structurally diverse lesions such as pyrimidine dimers arising upon UV irradiation and bulky chemical adducts arising upon exposure to environmental carcinogens or chemotherapeutic drugs. In view of the extraordinarily broad substrate specificity of NER, it is of interest to understand how a certain set of proteins recognizes various DNA lesions in the context of a large excess of intact DNA. This review focuses on contribution of photoaffinity labeling technique in the study of DNA damage recognition and following stages resulting in preincision complex assembly, the key and still most unclear steps of NER.

Keywords: nucleotide excision repair, damage recognition, preincision complex, photoreactive DNA