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Fig. 5
Biomechanical strains correlate with sites of cell maturation. Finite Element models showing locations of Von Mises strain (in microstrain) during mouth opening (IM and PH muscles are applied), closure (AM muscles applied) and in situations where the IM, AM and PH muscles are applied simultaneously to replicate rigid paralysis (A–C). Ventral view (A), Frontal view (B) and Lateral view (C). Confocal stacks of the ventral jaw and jaw joint in the double transgenic line col2a1:mcherry (red) and sox10:eGFP (green) in 5 dpf control zebrafish (D, D′) and immobilised (E,E′) zebrafish. Cells in yellow are seen where the two trangenes are coexpressed. Green cells (which are sox10+ve, col2-ve and therefore less differentiated) are concentrated in the joint regions and in the anterior tip of the MC. Note the altered distribution in the immobilised fish which corresponds to the shape changes observed. Finite Element models showing locations of Maximum principal strain [tension] (F) and Minimum principal strain [compression] (G) in the anterior tip of the MC when the IM muscle alone is applied. Confocal images of the MC anterior tip region (H,I) showing expansion of the distribution of sox10 positive cells in MS222 treated larvae (I) relative to controls (H).