Cell-level modelling of active forces in early-stage development*

Gastrulation is an essential, highly conserved process in the development of all vertebrate embryos, including humans. It involves large-scale cell and tissue movements. When not executed properly, it can lead to a wide range of congenital defects, or, in more extreme cases, cause abortion of development. Gastrulation requires the integration of critical cell behaviours such as cell differentiation, division, and movement through chemical and mechanical cell-cell signalling, to achieve the morphogenesis essential for proper functions. These interactions between signalling and cell behaviours create complex feedback loops between tissue, cell, and molecular length- and timescales that have evolved to enable the robust formation of complex multi-cellular structures. In this talk, using the vertex model for cell-level description of epithelial tissues, we will discuss how various active processes, such as mechano-chemical feedback, cell growth, division, ingression, etc. couple to cell mechanics and lead to pattern formation and flows in model tissues. We will also make qualitative comparisons to the primitive steak formation (i.e. the gastrulation) in chick embryos.