Figure 1. Isolation of single PGCs from 7.5 dpc early bud (A–H) and late bud (I–N) stage Blimp1-mRFP embryos.

(A,C,E,G,I,K,M) Light microscopy images. (B,D,F,H,J,L,N) Fluorescent microscopy images. At both EB and LB stages mRFP was detected as a cluster in the posterior part of the embryo (dashed rectangle) and in the visceral endoderm (arrowheads). For isolating PGCs, the posterior regions bearing PGCs were cut off carefully to remove the visceral endoderm (E,F,K,L). The resulting tissue fragments were disaggregated through trypsinization, and single PGCs with fluorescence were collected unambiguously using micromanipulators under a fluorescent microscope (G,H,M,N).