RNAi phenotypes of ES cells and iMEFs. (A) Proportion of TUNEL⁺ ES cells in KDs indicated. Means and standard deviations of triplicate samples are shown. (B) Colony morphology of ES cells depleted of the indicated proteins on day 4 of KD. Smc2, Mcm2, and Ints1 KDs exhibit a large number of rounded up and detached dead or dying cells. (C) Western blots for Smc2, Mcm, Ints1, and actin in ES cells depleted of the indicated proteins for 4 d. The arrow indicates Mcm2 in the pan-Mcm blot. (D) Morphology of iMEFs depleted of the indicated proteins. Cells were transfected on days 0, 2, 5, 8, and 11 and split back 1:8 on days 4, 7, and 10. Images were taken on day 11. Numbers in the bottom right corner represent the percentage of TUNEL⁺ cells in separate KD experiments. (E) Western blots for Smc2, Mcm, Ints1, and actin in iMEFs depleted of the indicated proteins at various points during the time course. “d” indicates length of KD in days. (C and E) The positions of molecular mass standards (in kilodaltons) are shown. (F) Proliferation of iMEFs depleted of the indicated proteins during the time course described in D. KD cells were split and counted at 3-d intervals. One of two independent experiments with comparable results is shown. Bars, 120 µm.