Fig 4

Surface topography profile of zebrafish bony rays and roughness calculation. (A) Procedure steps from the resection of the zebrafish caudal fins, to the analysis with AFM in tapping‐mode. (B) 3D representation of the cross‐section slices (obtained by cryosection process) analyzed by AFM. (C) The distal part of CTRL_REGEN group showing collagen fibers bundles (white single arrows) in flattened representations. (D) Approximation of the collagen fiber bundle from the white square in “B”; the double arrows shows the diameter of a periodic unit from a fibril (d ~ 75 nm). (E) Box‐plots with means (red horizontal line) and median (black horizontal line) of the roughness obtained from proximal and distal parts of fins by AFM. Capital letters indicate significant statistically difference between the different regions (proximal and distal) within the same treatment (p < .01). Lowercase letters indicate significant statistically difference between the same region (proximal or distal) among different treatments (p < .01).