Fig. 2. Mutants initiate migration and form bilateral clusters in a similar manner to wild-type embryos. (A-O) Dorsal views of wild-type, p53 and outsiders mutant PGC development at stages 10-14. Anterior is left in all figures. PGCs are labeled with an anti-Vasa antibody. (A) At stage 10, wild-type PGCs moved out of the posterior midgut. (F,K) The initial PGC movements in p53 and out appear normal. (B) At stage 11, bilateral segregation of PGCs occurred in the wild-type embryos. (G,L) PGCs in p53 and out mutants form bilateral clusters. However, there are occasionally PGCs left in the midline. (C) During stage 12, wild-type PGCs form clusters. (H,M) Bilateral clusters are also seen in p53 and out mutants. Note that some PGCs remained in the midline of some p53 embryos. (D) At stage 13, PGCs form tightly associated linear arrays of cells. (I,N) In both p53 and out embryos, most PGCs were aligned. However, isolated PGCs were observed. (E) At stage 14, PGCs in wild-type embryos coalesce with SGPs. (J,O) p53 and out mutant embryos exhibit very similar phenotypes. PGCs are able to migrate to the gonads; however, many PGCs persisted ectopic to the gonads.