Fig. 4

MZptk7audm400 mutants displayed delayed vertebrae mineralization, segmentation defects and a wavy notochord. (A,B) Representative lateral views of calcein staining images of MZptk7audm400 mutants and their control siblings at 7 dpf (A) and 15 dpf (B). Arrow points to the mineralization of vertebrae. (C) The number of mineralized vertebrae is significantly reduced in MZptk7audm400 mutants compared with their control siblings at 7 dpf (n=26 and 17, respectively; P<0.0001) and 15 dpf (n=13 and 25, respectively; P<0.001). (D) Examples of segmentation defects detected in MZptk7audm400 mutants upon calcein staining at 15 dpf, including wedged vertebrae (arrowhead), skipping of mineralization (bracket), V1-V2 fusion (arrow) and hemivertebrae (asterisks). (E) Representative lateral views of calcein staining images alone (top) or merged with brightfield images (bottom) of MZptk7audm400 mutants and their control siblings at 9 dpf (starved). Bracket indicates skipping of mineralization, and asterisks indicate aberrant mineralization initiation points. (F) Representative dorsal views of Alizarin Red staining alone (top) or merged with brightfield images (bottom) of MZptk7audm400 mutants and their control siblings at 15 dpf. The numbers of vertebrae and of myotomes are indicated in the upper and lower panels, respectively. Dashed line indicates the center of the vertebral axis. (G) Examples of severe bends and kinks detected in the anterior part of the spines of MZptk7audm400 mutants upon Alizarin Red staining (indicated by arrows). (H) Dorsal views of brightfield images of 2 dpf embryos focusing on the notochord. Dashed line indicates the boundaries of the notochord. Note the wavy morphology in the anterior part of the notochord in MZptk7audm400 mutants. P-values were calculated using two-tailed Welch's t-test. ***P<0.001, ****P<0.0001. Scale bars: 1 mm in A,B; 200 µm in D-H.