zyg-1 single centrosomes undergo posterior-directed asymmetric transitions along the AP axis. (A) Still frames from time-lapse sequences of wild-type (WT), zyg-1, and spherical zyg-1 embryos. Black dots mark centrosomes. The cell cycle stage is indicated on the left. (B) Still frames from a time-lapse sequence of a zyg-1 embryo expressing GFP::γ-tubulin and GFP::histone. Arrowheads mark the centrosome. The line marks the plane of focus for kymographs in C. Times are given in seconds to NEB. (C) Kymographs from time-lapse videos of representative embryos. WT and zyg-1 embryos express GFP::γ-tubulin and GFP::histone. zyg-1; gpr-1/2(RNAi) embryo expresses GFP::γ-tubulin only for clarity. (D) Fixed WT and zyg-1 embryos stained for MTs, DNA, and GPR-1/2. MTs, microtubules. Bars, 10 µm.