FIG. 5.

Expression of a bacterial resolvase protein improves WRN cell survival and recombination. (A) Vectors for expression of active or catalytically inactive (D70N substitution) forms of the bacterial resolvase protein RusA (NLS, nuclear localization signal; GFP, green fluorescent protein) (11). (B) Survival of control (c) or WRN (W) SV40-transformed fibroblast cell lines transfected with control (vector) plasmid or plasmid expressing inactive (+RusA^inactive) or active (+RusA^active) RusA protein and treated with cis-Pt. (C) cis-Pt-induced neo⁺-recombinant colonies per 10⁶ viable cells after transfection of control (c) or WRN (W) cells as described for panel B. ∗, statistically significant difference compared with control or RusA^inactive-transfected cells (see the text). The error bars indicate standard deviations for two to five replicate experiments.