Fig. 5. PLK-1 levels correlate with the timing of mitotic entry after par-2 or par-3 inactivation. (A,B,D,E) Images from DIC time-lapse microscopy of wild-type (A,D), par-2(RNAi) (B) or par-3(it71) embryos (E) (see corresponding Movies 1-4). Black arrowheads indicate cleavage furrow ingression; white arrowheads with intact outline indicate intact nuclei; white arrowheads with broken outline indicate nuclei undergoing NEBD, which is apparent by loss of the smooth line corresponding to the nuclear envelope; circles indicate centrosomes in AB, the separation of which gives an indication of the advancement of mitosis. Cleavage furrow ingression at the onset of cytokinesis in P₀ is defined as t=0, and the time after that is indicated in seconds. (C,F) Average duration of interphase ±s.e.m. in AB and P₁ in wild-type and par-2(RNAi) (C) or wild-type and par-3(it71) (F) embryos. See Table S1 in the supplementary material for numerical values and statistical analysis. (G) Relative PLK-1 levels ±s.e.m. in anterior and posterior of one-cell stage wild-type, par-2(RNAi) and par-3(it71) embryos. Wild-type anterior, 0.68±0.04, n=12; wild-type posterior, 0.45±0.03, n=12; par-2(RNAi), 0.61±0.08, n=9; par-3(it71), 0.47±0.06, n=7. Student's t-test for wild-type anterior and par-2(RNAi), P=0.1; for wild-type posterior and par-2(RNAi), P=1.7x10^-4; for wild-type anterior and par-3(it71), P=7.36x10^-7; for wild-type posterior and par-3(it71), P=0.42. PLK-1 levels in par-2(RNAi) embryos are similar to those of the wild-type anterior, whereas PLK-1 levels in par-3(it71) are similar to those of the wild-type posterior.