(A) let-92(RNAi) and paa-1(RNAi) one-cell embryos display phenotypes distinct from rsa-1(or598ts). ZYG-9 is used as a centrosome marker. (B) RSA-1 is observed at the centrosomes of wild-type and rsa-1(or598ts) embryos. (C) Yeast-two-hybrid assay indicates protein–protein interactions between the PP2A catalytic subunit, LET-92, and both RSA-1(WT) and RSA-1(or598). The PP2A structural subunit, PAA-1, interacts with the RSA-1(WT) protein but not RSA-1(or598). (D) Western blot probed with anti-PAA-1 and anti-tubulin (loading control). The band at the expected size of 55 kDa is lost in paa-1(RNAi) embryos. (E) Fixed wild-type embryos showing PAA-1 at the centrosomes and P-granules (punctae in posterior, right side of embryo). Arrows indicate location of one centrosome. rsa-1(or598ts) embryos have less PAA-1 at the centrosomes. Scale bar is 10 µm.