Figure 3.

WVPHEL mutants are hyperactive in HeLa cells. (A) Cells were transfected with 500 ng donor and 8 ng helper. After 14 days growth in G418 media, the cells were fixed, stained with 1% methylene blue in 70% ethanol and the stable transfectants were counted. Results with additional mutants are presented in Supplementary Figure S4. (B) Transfections with 500 ng donor plasmid were titrated with an increasing amount of wild-type and V119T helper plasmids. Error bars are the standard error of the mean after three independent experiments. Transposase expression across this range is not toxic (13). (C) The relative activity of the V119T mutation compared with wild-type from part B is plotted against the amount of helper plasmid.