FIG. 3.

Medaka ES cell donors adopt the zebrafish developmental program. Red fluorescent protein (RFP)-labeled MES1 cells were transplanted into zebrafish blastulae and monitored for differentiation into cardiomyocytes in the heart. (A–D) Micrographs of chimeras at the lateral view at 1 dpf (A and B) and 2 dpf (C, D). (D) Larger magnification of the area framed in (C), highlighting MES1-derived cardiomyocytes in the heart. (E) Micrographs of chimeras at the dorsal view, highlighting a reduction in the relative MES1 signal in 3 areas (a, b and c) and the heart (circled) from 5 dpf (E) to 10 dpf (F). One and the same chimera at different days of development is shown in (B–F). The anterior is to the left. Asterisks depict MES1 derivatives outside the heart. ey, eye; ht, heart; so, somites; tl, tail; ys, yolk sac. Micrographs are merges between red fluorescent optics and bright-field optics. Scale bars, 100 μm. Color images available online at www.liebertonline.com/scd