Characterization of premature liver polyploidy in DNA repair (Ercc1)-deficient mice.

ERCC1-XPF is the endonuclease that cuts 5' of the damage in nucleotide excision repair (NER). Unlike other NER proteins, ERCC1-XPF is also involved in recombination and the repair of DNA interstrand cross-links. Unique among the NER gene knockouts, Ercc1 null mice are severely runted with high levels of hepatocyte polyploidy.

The formation of UV-induced chromosome aberrations involves ERCC1 and XPF but not other nucleotide excision repair genes.

ERCC1-XPF, through its role in nucleotide excision repair (NER), is essential for the repair of DNA damage caused by UV light. ERCC1-XPF is also involved in recombinational repair processes distinct from NER. In rodent cells chromosome aberrations are a common consequence of UV irradiation.

Nucleotide excision repair gene (ERCC1) deficiency causes G(2) arrest in hepatocytes and a reduction in liver binucleation: the role of p53 and p21.

A wide range of DNA lesions, both UV and chemically induced, are dealt with by the nucleotide excision repair (NER) pathway. Defects in NER result in human syndromes such as xeroderma pigmentosum (XP), where there is a 1000-fold increased incidence of skin cancer. The ERCC1 protein is essential for NER, but ERCC1 knockout mice are not a model for XP.