Figure 1

katnb1 mutant zebrafish exhibit defining attributes of IS

(A–D) Representative lateral views of calcein-stained katnb1^mh102/+ (A & A’; N = 2, n = 24) and katnb1^mh102/mh102 (B & B’; N = 2, n = 13) fish at 12 dpf (6 mm average length); and of katnb1^mh102/+ (C & C’; N = 4, n = 53) and katnb1^mh102/mh102 (D & D’; N = 4, n = 18) fish at 17 dpf (7 mm average length). Note onset of spinal curvatures in katnb1^mh102/mh102 zebrafish (arrowheads) in the absence of congenital vertebral malformations. Squares indicate location of higher magnification images (A′–D′). Scale bars, 1 mm.

(E–H) Three dimensional microCT projections of representative 3-month-old katnb1^mh102/+ (E & F; N = 2, n = 5) and katnb1^mh102/mh102 (G & H; N = 17, n = 68) zebrafish viewed in sagittal (E & G) and coronal (F & H) planes.

(I–L) Quantification of curve severity, direction, and position along the DV (I, J) and ML (K, L) axes of katnb1^mh102/mh102 mutant zebrafish. (I, K) Graphs depicting spinal curvatures of individual mutant fish: x axis indicates vertebral position of curve apices along the rostral to caudal plane; Y axis indicates magnitude of curvature (Cobb angle). Positive Cobb angles represents kyphotic curves in the DV axis and rightward curves in the ML axis. Negative Cobb angle represents lordotic curves in the DV axis and leftward curves in the ML axis. (J, L) Graphs depicting sums of all Cobb angle measurements in DV (J, p = 0.72) and ML (L, p = 0.31) axes for male and female katnb1^mh102/mh102 fish (N = 6, n = 47). Statistical analyses were performed using student’s t test.

(M and O) Quantification of curve severity, direction, and position along the DV (M) and ML (O) axes of ptk7a^hsc9/hsc9 mutant zebrafish.

(N and P) Quantification of curve severity as a measure of total Cobb angle, comparing katnb1^mh102/mh102 (N = 17, n = 68) and ptk7a^hsc9/hsc9 (N = 8, n = 17) mutant animals along the DV (N, p = 0.613) and ML (P, p = 0.0014) axis.