The dnd RNA Identifies Germ Cell Origin and Migration in Olive Flounder (Paralichthys olivaceus)

Figure 5

Schematic summary of Podnd transcripts distribution during embryogenesis in olive flounder. Red spots indicate Podnd signals. (a) 2-cell, (b) 4-cell, (c) 8-cell, and (d) 16-cell stages. ((a)–(d)) Podnd are located at the end of the first, second, and third cleavage furrows, (e) 32-cell stage: the signals aggregated into four single blastomeres, (f) morula stage, (g) blastula stage: the Podnd-positive cells increased from one to two and the sister cells are located adjacent to each other at every positive area, (h) early gastrula: Podnd mRNA mainly localized at the marginal region of the blastoderm, (i) mid gastrula stage: some Podnd-positive cells are located at the germ ring and the others moved towards to the dorsal side, ((g1) and (g2)) late gastrula stage, (g1) side view and (g2) top view: Podnd-positive cells aligned along both sides of the body axes in the posterior of the trunk region, (k) somite stage: Podnd-positive cells aligned as two lines along both sides of the embryonic body in the trunk region, (l) the Podnd-positive cells formed clusters above the hind gut in the presumptive genital ridge, (m) 1-2 d after hatching: Podnd-positive cells cluster in the presumptive genital ridge region at the posterior dorsal sides of gut, and (n) cross section: dnd-positive cells aligned at the genital ridge which was at the dorsal sides of the hind gut and ventral side of notochord.