Centrosome protein centrin 2/caltractin 1 is part of the xeroderma pigmentosum group C complex that initiates global genome nucleotide excision repair

Nucleotide excision repair (NER) is carried out by xeroderma pigmentosum (X P) factors. Before the excision reaction, DNA damage is recognized by a com plex originally thought to contain the XP group C responsible gene product (XPC) and the human homologue of Rad23 B (HR23B). Here, we show that centri n 2/caltractin 1 (CEN2) is also a component of the XPC repair complex. We d emonstrate that nearly all XPC complexes contain CEN2, that CEN2 interacts directly with XPC, and that CEN2, in cooperation with HR23B, stabilizes XPC , which stimulates XPC NER activity in vitro. CEN2 has been shown to play a n important role in centrosome duplication. Thus, those findings suggest th at the XPC-CEN2 interaction may reflect coupling of cell division and NER.