Establishment of poly(ADP-ribose) polymerase-deficient mouse embryonic stem cell lines

Many studies revealed that poly(ADP-ribose) polymerase (Parp) is involved i n DNA-damage recovery, cell-death induction and maintenance of genomic stab ility. We generated mouse Parp(+/-) embryonic stem (ES) cell lines by disru pting one allele of Parp exon 1 with a neomycin-resistance gene-cassette an d subsequently produced Parp(-/-) ES cells by disrupting the remaining alle le with a puromycin-resistance gene-cassette. Parp activity was decreased t o half in Parp(+/-) ES cell clones and lost in Parp(-/-) ES cell clones. Gr owth rates of Parp(+/-) and Parp(-/-) ES cell clones were similar to that o f parental J1 ES cells, indicating that Parp is not required for ES cell pr oliferation. These Parp(-/-) ES cells will be useful to study biological ro le of poly(ADP-ribosyl)ation reaction.