Figure 5.

Irradiation of embryos reduces the number of PGCs. (A) Schematic representation of the localization of PGCs. At E6.5, epiblast cells that become directed to the PGC fate are located in the proximal region of the embryo close to the embryonic/extraembryonic boundary (shaded area). At E8.5, PGCs are located at the base of the allantois around the hindgut pocket (Arrow shows the view for B–D). (B –D). Embryos were stained with alkaline phosphatase (blue) to mark PGCs. (B) Control; (C,D) embryos irradiated with 0.5 Gy at E6.25 or E7.25, respectively, and collected at E8.5. (Arrows) Stained PGCs. (e) Embryonic region; (ex) extraembryonic region; (D) distal; (Pr) proximal.