Cardiac valve genes were abnormally expressed in the AVC of scote382 mutant hearts. (A-R) Wild-type (A-C,G-I, M-N,Q) and scote382 (D-F,J–L,O-P,R) embryos were analyzed by in situ hybridization with cardiac valve markers notch1b (A-F), bmp4 (G–L), dll4 (M-P) and spp1 (Q–R) at 48hpf (A,D,G,J), 60hpf (B,E,H,K,M,O), and 72hpf (C,F,I,L,N,P–R). Note that endocardial notch1b and dll4 were ectopically expressed in the ventricle of scote382 mutants but myocardial bmp4 was not affected in scote382 mutants from 48 to 72hpf. spp1, an endocardial–mesenchymal transition marker gene, was not expressed in the AVC of scote382 mutants (red arrowhead in R). The atrium and ventricle are demarcated with red arrowheads. Black arrowheads (Q,R) point to the outflow tract. a, atrium; v, ventricle; wt, wild type. Dotted lines outline the heart.