Fig. 6 Antisense morpholino nucleotides (MOs) effectively affected development of heart as well as expression of vmhc promoter reporter gene (green fluorescent protein [GFP]). Living embryos are shown at 48 hours postfertilization (hpf). A-H: Representative transgenic embryos showing the effects of ventricle-specific GFP expression in vmhc:gfp compared with the control (A; Mock, injection buffer injected), GATA4 MO-injected (B; MO4), GATA5 MO-injected (C; MO5), GATA6 MO-injected (D; MO6), GATA4 and GATA5 MO-injected (E; MO4+5), GATA4 and GATA6 MO-injected (F; MO4+6), GATA5 and GATA6 MO-injected (G; MO5+6), GATA4, GATA5 and GATA6 MO-injected (H; MO4+5+6) embryos. At 48 hpf, the control embryos showed no significant difference in GFP expression compared with either the GATA4 or GATA6 morphants. GATA5 morphant displayed cardia bifida but the GFP intensity was not reduced (C). In contrast, simultaneous injection of GATA4 and GATA6 MOs resulted in embryos with significantly decreased ventricular GFP expression (F). Views are dorsal and anterior to the left. The percentages of embryo with each intensity are indicated in parentheses.