Figure 1
Cardial phenotypes of raw mutant embryos. (A, B, C, G, H, I, M, N) Wild-type (WT) embryos; (D, E, F, J, K, L, P, Q) raw1 mutant embryos. (A) EPC was visualized with anti-Eve antibodies at stage 16. (D) EPC was completely absent in raw1 mutant embryos. (B) The EC11 antibody was used to label pericardial cells at stage 16. (E) Pericardial cells were abolished in raw1 mutant embryos. (C) E2-3-9 enhancer trap line shows the presence of 2 svp-specific cardioblasts per hemisegment in WT embryos (arrows). (F) Most svp-expressing cardioblasts were absent in raw mutants. (G) The expression of Tin in dorsal mesoderm was revealed using anti-Tin antibodies in WT embryos at stage 12. (J) The expression of Tin was not affected in raw1 mutant embryos at similar stages. (H) Tin was expressed in heart cells at stage 14 in wild type embryos. (K) Overproduction of heart precursors was observed in raw1 mutant embryos at stage 14 (braces). (I) Tin was confined in matured myocardial cells at stage 16 in the wild type (L). The number of myocardial cells was greatly reduced in raw1 mutants during late embryogenesis (brackets). (M) Cardial and muscle cells were monitored by the expression of him-GFP reporter at stage 14. (P) The number of him- GFP expressing cardial precursors increased dramatically (braces). Note that the enhancer activity of him was also enhanced in musculature of raw1 mutants at stage 14. (N) The expression of him-GFP was confined to all cardial and pericaridial cells, while its expression in muscle cells was reduced greatly at stage 16. (Q) The him- GFP expressing heart cells were dramatically reduced (brackets). Note that the expression of him- GFP in muscle persisted in raw1 mutants during late embryogenesis. (O) Number of heart cells in wild-type (gray bar) and raw1 mutant (black bar) embryos at stage 14 and 16 was revealed by Tin immunoreactivity and expression of him-GFP reporter. Data were expressed as the mean ± SD and were analyzed by Student's t-test (n = 15). * indicates p < 0.01; ** indicates p < 0.001. st, stage.