Fig. 5. Mechanotransductive triggers of active morphogenetic movements in bilaterian early embryogenesis and organogenesis.

a,b- Fog-dependent mechanical induction of Rho-dependent apical stabilisation of Myo-II by snail-dependent Myo-II-dependent pulsations (red loop I in b), potentially auto-amplified (grey loop arrow in mid-sage 6 (10’)). Fog-dependent mechanical stimulation of Myo-II-dependent posterior endoderm invagination initiation by the stretching induced by mesoderm invagination (red loop II in b) auto-amplified (blue box, grey loop arrow (potentially Fog dependent)), suggested as also Fog-independent (black arrow in b leading to full endoderm invagination). Adapted from⁷². c Mechanical induction of apical stabilisation of Myo-II by contractile forces of apoptotic cells in folding initiating joint formation in Drosophila leg organogenesis. Adapted from⁷⁸.