Supplementary materials - Supplementary Figures

Supplementary materials - Supplementary Figures

Mesenchyme

bone

Figure 1: Left: sketch of the initial interface used for the linear analysis. Right: close view of the initial numerical interface from Figure 3 of the Main article (top left).

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Figure 2: Bone deposition patterns in skull vault sutures. (a) 3D reconstruction of the sagittal suture of a P20 mouse from synchrotron x-ray microtomography data with a 1.36 voxel size; upper view; osteocytes are represented in red and are more concentrated in convex regions (blue arrowhead) than in concave regions (red arrowhead); (b) 3D reconstruction of the same data-set in frontal section; indirect signs of bone resorption in the concave regions (arrowhead); osteocytes are represented in yellow.

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Figure 3: (a) LacZ staining on a frontal section of a sagittal suture of an adult R26-Wnt1-Cre mouse; neural-crest derived cells appear in blue; a central band in the mesenchyme of the suture (arrowhead) is neural-crest derived; (g) same sample; the osteocytes that integrate into the bone are neural-crest derived and migrate from the central mesenchyme (arrowhead).

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Figure 4: Sutural interdigitations and Sharpey’s fibres in the rat. (a) Fragment of the frontal suture of an adult Rattus rattus, 3D reconstruction from synchrotron X-ray microtomography data with a 0.678 voxel size. (b, c) Sections b and c, respectively defined in figure (a), showed interdigitations and collagen fibres connecting the 2 borders of the suture (red arrows); sections from synchrotron x-ray microtomography data with a 0.678 voxel size. 4

Figure 5: Sutural interdigitations in a basal extant actinopterygian. Juvenile (a) and adult (b) parietal sutures in Polypterus bichir showing the progressive complexification of the suture in the coronal plane; sections from synchrotron X-ray microtomography data with a 14.92 voxel size (juvenile sample) and a 30.2 voxel size (adult sample).

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