Figure 2

Figure 2

Two-dimensional (2D) analysis of vertebral thickness and intervertebral disk (IVD) structure in Chi/+ and p3h1^−/− zebrafish. (A, B) 2D vertebral thickness (V.Th) distribution along the z-axis of WT and untreated mutants (i) and between untreated and treated mutants (ii). Dashed lines outline the vertebral centrum and abdominal (aEP) or caudal (cEP) endplates. (C) IVD structure drawing displaying vertebral endplate elements and toluidine blue–stained sections showing WT and treated and untreated Chi/+. Scale bar: 40 μm. (D) IVD structure qualitative evaluation in WT, Chi/+ (i), and chi/+ untreated and treated with 4PBA, ALN, and 4PBA + ALN (ii). In the graph, the percentage of normal, enlarged, or dislocated IVDs on total number of analyzed IVDs is reported (^*p < .05, ^**p < .01, ^****p < .0001). (E, F) 2D landmark scatterplot of WT and untreated mutant vertebrae (i) and untreated and treated mutant vertebrae (ii). Each dot represents a single landmark. Abbreviations: ALN, alendronate; cf, collagen I fiber bundles; dc, dense collagen I fiber bundles; el, elastin layer; fb, fibroblasts; nc, notochord cells; ne, notochord epithelium; ns, notochord sheath; Ob, osteoblasts; ot, osteocytes; 4PBA, 4-phenylbutyrate.