Abstract

This talk concerns “dorsal closure”, a dynamic and complex process during the embryogenesis of Drosophila. Experiments have documented distinct phases of dorsal closure, each with rich and sometimes contradictory observations. We build a mathematical model to rationalize the results and test various hypotheses put forth by experimenters. The cells are coupled mechanically through the position of the nodes and the elastic forces on the edges. Besides, each cell has radial spokes on which myosin motors can attach and exert contractile forces on the nodes, the myosin dynamics itself being controlled by a signaling molecule. This simple model successfully reproduces the cell and tissue pulsation in the early phase of dorsal closure, as well as the consistent contraction in the slow phase through a cellular ratcheting mechanism.

Co-authors: Qiming Wang (Univ of British Columbia), Len Pismen (Technion)