Fig. 1

Vmat2 mutants. A, Results of the HRM analysis showing the distinctive melting curves of each genotype. B, Sequencing chromatograms of tail-clipped DNA showing the sequence and the newly generated stop codon of a vmat2^−/− zebrafish. C, Identification of genotypes by restriction digestion of PCR products. D, Bar charts showing results of reverse transcription-quantitative PCR (RT-qPCR) analysis on larvae of the indicated genotype at 6 dpf. Vmat2^−/− larvae exhibit 60% less vmat2 transcript than vmat2^+/+ larvae. E and F, Ventral views of whole-mount 6 dpf larval brains, anterior to the left, processed for vmat2 RNA in situ hybridisation (ISH). Vmat2 expression was clearly lower in mutants than in vmat2^+/+ larvae. Scale bar = 75 µm. n = 5 for each genotype. G, Bar chart showing heart rate in larvae of the indicated genotype at 6 dpf. n = 7 for each genotype. The heart rate was lower in mutants than in vmat2^+/+ siblings. Data are mean ± SEM. Student's t test was used for statistical analysis. ^†P < .01. ^‡P < .001