Figure 2

vwa1 knockout in zebrafish causes craniofacial defects. (A) General phenotypic changes in F0 mosaic and F2 homozygous embryos. Morphology was assessed at 5 dpf; un-injected WT larvae were used as controls (WT). Black arrow, lower jaw underdevelopment. Blue arrow: altered swim bladder development. Red arrow: pericardial edema. (B) Cartilage formation at 5 dpf, detected by Alcian Blue staining. Compared to controls, F0 crispants and F2 homozygous larvae showed hypoplastic Meckel’s cartilage and palatoquadrate, a significantly widened angle between ceratohyals, and a reduction in the number of hypoplastic ceratobranchial cartilages. m, Meckel’s cartilage; pq, palatoquadrate; cb, ceratobranchial; ch, ceratohyal; hs, hyosymplectic. (C) RT-qPCR analysis of vwa1 expression levels in F0 crispants and the −7 bp deletion mutant line at 5 dpf. n = 3 independent experiments. * p < 0.05; ** p < 0.01.