Cytoplasmic streaming and amoeboid cell motility: Mathematical models and computational methods

University Of California-Davis, Davis CA

Investigators

Abstract

Recent experiments on cell locomotion through three-dimensional fibrous matrices have raised new questions about the basic mechanisms of cell locomotion. In particular, they have shown that some cells use pressure-driven protrusions called blebs to squeeze their way through the gaps in the matrix, and it has been hypothesized that this method of locomotion can be achieved without adhesive interactions with the surrounding environment. The goal of this project is to develop a comprehensive mathematical model of a blebbing cell and use this modeling framework to explore how cells use cytoplasmic streaming for locomotion. This model will be the first to provide an integrative picture of how local mechanical and chemical factors work together to drive directed cell locomotion. These models will involve the mechanochemical chemical interactions between the cytoskeleton, cytosol, cell membrane, extracellular fluid, and the surrounding solid structures. A necessary component to this project is accounting for the changing geometry of the cells. Given the complexity of the problem, efficient numerical simulations are needed to explore the models. The investigators develop a new mixed Eulerian-Lagrangian framework to unify the mathematical description of these complex interacting materials. Using this framework, new and efficient methods for solving the coupled equations that arise in the model are developed. Many problems in biology involve interactions between mechanics complex multiphase fluids, chemical reactions, and deforming structures. For example, the dynamics of growing bacterial biofilms and the transport of mucus in the respiratory system are two such processes. Our models and numerical methods can be adapted to explore these important complex systems. A graduate student will be trained as part of this research project. This project is ideally suited for training graduate students with the broad background necessary for research in mathematical biology and scientific computation. The student will interface directly with the experimental collaborators involved in the project to learn the essential skill of communicating ideas across disciplines.