Figure 7

Schematic drawings show difference in the defects of germ cell migration in Adamts9 or its ortholog knockouts in C. elegans, Drosophila, and zebrafish models. Green dots denote primordial germ cells (PGC). Only the posterior gonad arm is shown for C. elegans. (A) PGCs migrate in wildtype C elegans, (B) no migration occurs in gon-1 mutant (modified from Blelloch and Kimble^14,15). (C) PGCs migrate correctly in wildtype Drosophila and clustered together at gonadal ridge at stage 16 embryo. (D) PGC mis-migrate in AdamTS-A knockout embryos (modified from Ismat et al.¹⁷). E–H. All PGC migrate toward gonadal ridge in zebrafish embryos, though these PGC were distributed in wider area (D2 > D1) in the Adamts9 knockouts at 15 h post fertilization (hpf, E: wildtype; F: Adamts9 KO) and 24 hpf (G: wildtype; H: Adamts9 KO), i.e. delayed migration. The migration of PGC is completed around 24hpf in wildtype embryos, but 48hpf in Adamts9 KO zebrafish embryos (see Fig. 6 for detail).