| CURRENT AND RECENT PROJECTS
- Simulation of tissue morphogenesis
- Cell mechanics: collective migration, fluidization and activation
- Tear film breakup in healthy and infected eyes
- Dynamics of moving contact lines
- Morphology of sheared foam
- Interfacial dynamics in complex fluids
- Self-assembly of micro-particles and droplets
(in collaboration with Tony Harris and Rodrigo Fernandez-Gonzalez of University of Toronto, and Len Pismen of the Technion)
Tissue growth and morphogenesis are fundamental processes in developmental biology. On the cellular level, cell size growth, cell division, and cell shape changes are controlled by signaling molecules that, in turn, are expressed according to a genetic blueprint. On the tissue level, different cell types arrange themselves in spatial patterns that eventually form the tissue or organ. Evidently, morphogenesis involves coupling between biochemical and mechanical mechanisms on several length and time scales. As an example, a schematic of the evolving epithelial morphology, triggered by loss of Dpp signaling, is shown below.
In a recent project, we built a mathematical model for dorsal closure during the embryogenesis of Drosophila. The amnioserosa tissue contracts through several phases during dorsal closure under the coordinated actions of the cell shape pulsation and "purse-string" contraction of a supracellular actin cable. Each is the result of mechano-chemical coupling involving intricate signaling pathways and actomyosin remodeling. In the following movies, the prediction of the model (left) is compared with an experimental observation (right) of Blanchard et al. (image and video used with permission, © 2010 The Company of Biologists).
More recently, we have probed the interaction of signaling proteins that control the dorsal closure process, and simulated cell intercalation through the T1 transition during Drosophila germband extension. Ongoing work deals with tissue-level simulation of the convergent extension of the germband, with a focus on the rosette dynamics, as well as collective migration of neural crest cells driven by contact inhibition and co-attraction.
|(Apical constriction and axial shortening produce an apical epithelial invagination. Adapted from Widmann and Dahmann with permission, © 2009 The Company of Biologists.)