Validation of the MEP by microdissection. (A) Survival curves of diploid parent (UCC8600, n = 147, median = 37) and MEP (UCC5185, n = 90, median = 36) strains generated by micromanipulation on YEPD without estradiol. Median life spans are not significantly different (Mann–Whitney nonparametric t-test, P = 0.3904). (B) Survival curves of MEP strain UCC5185 generated by micromanipulation on YEPD with 1 μm estradiol (+ED, n = 39, median = 36) or without it (−ED, n = 90, median = 36). The survival curve for +ED includes only naive mother cells that did not exhibit rapid M-phase arrest upon transfer to estradiol. (C) The distribution of the number of cells per microcolony generated by daughter cells born during +ED RLS analysis presented in B. (D) Survival curves of UCC5185 naive daughters (n = 118, median = 2) transferred to YEPD + 1 μm estradiol and their resulting progeny (granddaughters, n = 269, median <1). The two leaky daughters have been censored from the analysis. In each case, the RLSs of cells that failed to complete a single division were scored as 1 generation.