Activity and topological defects in 3D morphogenesis

During morphogenesis, a group of cells can change shape and orientation, including breaking previous global symmetry. Simulations of this process often impose this symmetry breaking on the system, whereas we would like to make these changes emergent from the evolution of the individual cells. We extend a previously developed discrete 3D cell model, which can capture cell morphological effects such as budding, gastrulation, and neurulation. This model couples the evolution equations of two polarities and position and its simplicity allows the simulation of thousands of interacting cells at reasonable computational cost. We now extend it to include the presence of a diffusive chemical agent, activity, and parameter dependence on topological defects in polarity. With a particular interest on how these results relate to organoids, we examine the presence of these effects on the morphological changes.