Fluid model of epithelial morphogenesis: Oscillations and structuring.

We have revised a mathematical model of epithelial morphogenesis by Belintsev et al. (1987) (BB model) taking into account the oscillatory nature of morphogenesis and stability analysis (Cherdantsev, 2014). Following the BB model in considering the feedback control of cell shape changes by mechanical forces, we modify it to represent epithelial surface movements observed in different types of Metazoan gastrulation.

Relocations of cell convergence sites and formation of pharyngula-like shapes in mechanically relaxed Xenopus embryos.

Influence of the relaxation of mechanical tensions upon collective cell movements, shape formation, and expression patterns of tissue-specific genes has been studied in Xenopus laevis embryos. We show that the local relaxation of tensile stresses within the suprablastoporal area (SBA) performed at the early-midgastrula stage leads to a complete arrest of normal convergent cell intercalation towards the dorsal midline. As a result, SBA either remains nondeformed or protrudes a strip of cells migrating ventralwards along one of the lateral lips of the opened blastopore.