Survival, mutagenesis, and host cell reactivation in a Chinese hamster ovary cell ERCC1 knock-out mutant

Positive selection-negative selection gene targeting was used to disrupt the nucleotide excision repair gene ERCC1 in a Chinese hamster ovary cell line, CHO-K1. Southern and Northern analysis showed that a cell clone isolated by this targeting approach, CHO-7-27, had an ERCC1 gene structure consistent with targeted disruption of ERCC1 exon V, and did not express ERCC1 mRNA. CHO-7-27 was further characterized with respect to UV and mitomycin C …