Fig. 1. Cardiac morphology in wea mutant embryos. (A-D) Lateral views of live embryos at 48 hpf, anterior to the left. (A,B) Atrial plane of focus. Compared with the wild-type (wt) atrium (A, arrow), the wea mutant atrium (B, arrow) appears dilated. (C,D) Ventricular plane of focus. Compared with the wild-type ventricle (C, arrow), the wea mutant ventricle (D, arrow) appears slightly compact. Mutant embryos shown are wea^m58 homozygotes. The wea^m58 and wea^sk7 mutant phenotypes are identical in all characterized aspects; data in all figures are from wea^m58 mutants.