Fig. 1
From: Mechanism and regulation of DNA damage recognition in nucleotide excision repair
A model for DNA damage recognition and verification in mammalian GG-NER. The XPC protein complex recognizes and binds to DNA sites with disrupted/destabilized base pair(s) regardless of the presence (left) or absence (right) of relevant lesions. After loading of the TFIIH complex, the XPD helicase subunit in TFIIH scans a DNA strand in 5′-3′ direction in conjunction with XPA, and the presence of a lesion is finally verified by blockage of this translocation. Even though a lesion is not present exactly at the XPC-bound site, this scanning mechanism may provide NER with a chance to find some nearby lesions