Fig. 4. RNAi of OID genes affects cortical granules. (A) Organization of the C. elegans gonad, showing approximate cell cycle stages based upon the position of oocytes and embryos in wild-type animals. (B-D) Cortical granules labeled with UGTP-1::GFP (indicated by arrows; insets show higher magnification of vesicles). In wild-type animals, embryo +1 was undergoing meiosis I and contains cortical granules, whereas embryo +2 was in the first mitotic division and lacks cortical granules. (C) chs-1(RNAi) oocytes and embryos showed the same UGTP-1::GFP pattern as the wild type. (D) apc-2(RNAi) caused retention of clustered UGTP-1::GFP-labeled cortical granules. (E) sep-1(RNAi) caused retention of UGTP-1::GFP-labeled cortical granules in the first three embryos. Scale bar: 10 µm.