PAR-5 depletion rescues the furrow initiation delay seen in lin-5(RNAi) embryos. (A) Schematic representation of an evolutionarily conserved pathway required for actomyosin ring assembly and the role of PAR-5 in negatively regulating ZEN-4 and CYK-4 oligomerization. (B–D) Representative images from the time-lapse confocal microscopy of embryo coexpressing CYK-4-mNG in control (n = 5) (B) and par-5(RNAi) (n = 5) (C), and par-5(RNAi); lin-5(RNAi) (n = 11) (D). n is the number of embryos analyzed. The scale bar is 10 µm. Insets with the corresponding images show the magnified view of the furrow region. Here, the scale bar is 5 µm. (E–H) Representative images acquired by time-lapse confocal microscopy of control embryos coexpressing GFP^Mem. and mCherry^Tub., which are either left untreated (E), or depleted for PAR-5 (F), lin-5(ts) embryos expressing GFP^Mem. and mCherry^Tub. that are treated with lin-5(RNAi) (G), or lin-5(ts) embryos expressing GFP^Mem. and mCherry^Tub. that are treated with lin-5(RNAi) and par-5(RNAi) (H), as indicated. Control (n = 17); par-5(RNAi) (n = 10); lin-5(ts)+lin-5(RNAi) (n = 10); lin-5 (ts)+lin-5(RNAi)+par-5 (RNAi) (n = 12). 0 s represents NEBD. n is the number of embryos analyzed. The scale bar is 10 µm.