Fig. S3

Characterization of hematopoietic progenitors in embryonic c-myb mutants at 24 h postfertilization (hpf). (A) Low power view of wild-type and mutant embryos simultaneously hybridized with probes specific for scl (red fluorescence) and c-myb (green fluorescence). The photograph of the wild-type embryo is merged from 45 optical slices at 5-μm thickness; the photograph of the mutant embryo is merged from 33 slices. (B) High-power view of A, focusing on the intermediate cell mass (ICM) and posterior blood island (PBI; this panel is also shown in Fig. 3A). The photograph of the wild-type embryo is merged from 22 optical slices at 5-μm thickness; the photograph of the mutant embryo is merged from 20 slices. (C) Same as in B but presenting only c-myb signals (green), indicating that c-myb levels are increased rather than the number of c-myb positive cells. (D) Same as in B but presenting only scl signals (red).