The Role of Mechanics and Geometry in Cell and Tissue Morphodynamics

Abstract:  

Living cells and tissues undergo dramatic changes in shape in response to mechanical forces, yet the physical principles governing these transformations are often unclear. Despite the apparent complexity of cell and tissue morphodynamics, their dynamics may sometimes be understood from surprisingly simple physical principles. I will discuss two examples. First, I will examine the mechanics of nuclear deformation as cells migrate through confined geometries. A model based on conservation of nuclear volume and the excess surface area stored in the nuclear lamina explains how the nucleus can undergo large, drop-like deformations and predicts when confinement generates tension in the lamina. Second, I will consider the dramatic collapse and eversion of epithelial acini. Experiments and mechanical modeling suggest that differences between apical and basal surface tensions provide the energetic driving force for this transformation. New dynamic simulations reveal a possible mechanical pathway by which an initially polarized epithelial cyst becomes unstable, collapses, and ultimately everts. Together, these examples illustrate how geometry, surface tension, and mechanical constraints can produce complex morphodynamics across cellular and multicellular scales.

Bio:

Richard B. Dickinson is Professor and Interim Chair of Chemical Engineering at the University of Florida. He received his Ph.D. in Chemical Engineering from the University of Minnesota and completed postdoctoral research at the University of Wisconsin–Madison and the University of Bonn, Germany. His research lies at the intersection of engineering, physics, and cell biology, with an emphasis on the mechanics of cell migration, cytoskeletal and nuclear mechanics, and the role of mechanical forces in cell and tissue morphodynamics. He previously served as Chair of Chemical Engineering at UF and as Division Director of Chemical, Bioengineering, Environmental, and Transport Systems (CBET) at the National Science Foundation. His honors include the NSF CAREER Award and election as Fellow of the American Institute of Chemical Engineers (AIChE) and of the American Institute for Medical and Biological Engineering (AIMBE).