(A) Live embryos of the indicated genotypes and stages expressing GFP::PGL-1 (green) and mCherry::H2B (red) or GFP::PGL-1 only (last two). Arrows in meg-3 meg-4 point to oocyte granules. For pptr-1 zygotes, the number of zygotes with visible posterior P granules is indicated. P0 is 1-cell stage, P1 is 2-cell stage, P4 is 28-cell stage. (B) Number of GFP::PGL-1 granules in zygotes in anaphase of the first mitosis. Each dot represents a different zygote, and mean and standard deviation are shown. Asterisks indicate data that are statistically significantly different from wild-type (one asterisk: p < 0.005, three asterisks: p < 0.0001). (C) Percent sterility of adult hermaphrodites of the indicated genotypes grown at 20°C. Number of hermaphrodites scored (n) is written above the x axis. (D) Primordial germ cells in the L1 larval stage expressing GFP::PGL-1. By this stage, PGCs express P granule components (Kawasaki et al., 2004). Perinuclear P granules form in all three genotypes. GFP::PGL-levels are lower in the meg mutants due to the lack of P granules inherited from the early embryonic stages. Full genotypes are meg-1(vr10), meg-1(vr10) meg-2(RNAi), meg-3(tm4259), meg-1(vr10) meg-3(tm4259), meg-4(ax2081), meg-3(tm4259) meg-4(ax2026), pptr-1(tm3103), pptr-1(tm3103);meg-1(vr10), pptr-1(tm3103);meg-3(tm4259), mbk-2(pk1427) and mbk-2(pk1427); meg-3(RNAi) meg-4(RNAi).