Figure 1

(A) Schematics of the vmhcl mutant allele generated using TALEN. The Hinfl restriction enzyme recognition site used for genotyping is boxed. Dashed lines indicate deleted nucleotides. The asterisk indicates an early translational stop codon. fs, frameshift. (B) Quantitative reverse transcription PCR (RT-PCR) revealed reduced expression of the transcript in both heterozygous (vmhcl^e13/+) and homozygous (vmhcl^e13/e13) mutants. (C–E) Representative images and quantification of the VSA and atrial surface area (ASA) in fish at 3 dpf. The asterisk indicates edema. A, atrium; V, ventricle; n = 4; 1 way ANOVA. (F) Percent FS of the vmhcl^e13/e13 mutant compared to WT control at 3 dpf. n = 14; data are presented as the mean ± SD. Paired 2-tailed Student’s t tests were used for statistical analyses. (G and H) The vmhcl^e13/e13 mutants exhibited disrupted sarcomere structure at 3 dpf. Fluorescence immunostaining using anti-myosin heavy chain 1 (F59) and anti-troponin T antibodies are shown. (I) Transmission electron microscope (TEM) images confirmed the disrupted sarcomere structure in the vmhcl^e13/e13 mutants. Arrows indicate sarcomeric Z-discs in the vmhcl^e13/e13 mutant compared to WT control. Asterisks point to degenerated sarcomere in the vmhcl^e13/e13 mutant. Scale bars: 500 μm in C, 200 μm in D, 10 μm in G and H, and 2 μm in I.