Effect of the rad26Δ mutation on survival of MMS-treated yeast cells lacking the APN1 and APN2 genes or, in addition, also lacking the RAD14 gene. Cells were treated with the indicated amounts of MMS (percentages, vol/vol) for 20 min at 30°C, following which MMS was inactivated with sodium thiosulfate and appropriate dilutions of cells were plated on YPD for viability determinations. The survival curves represent an average of three experiments for each strain. W.T., wild type.