The DNA damage-recognition problem in human and other eukaryotic cells: the XPA damage binding protein

摘要: The capacity of human and other eukaryotic cells to recognize a disparate variety damaged sites in DNA, selectively excise repair them, resides deceptively small simple protein, 38-42 kDa zinc-finger binding XPA (xeroderma pigmentosum group A), that has no inherent catalytic properties. One key its damage-recognition ability DNA-binding domain which combines zinc finger single-strand region may infiltrate single-stranded regions caused by helix-destabilizing lesions. Another is the augmentation interactions with proteins helicases co-operate are unloaded at site facilitate further unwinding DNA subsequent catalysis. properties these reactions suggest there must be considerable conformational changes associated provide flexible fit wide structures DNA.