Collaborative Research: Multiscale Study of Active Cellular Matter: Simulation, Modeling, and Analysis

New York University, New York NY

Investigators

Abstract

Active cellular matter is the basis of novel synthetic active fluids made of mixtures of suspended cytoskeletal filaments and molecular motors. By consuming chemical fuel, the molecular motors (e.g., kinesins) can bind to and create actively moving crosslinks between the biofilaments (e.g., microtubules) to drive their relative motion, which leads to large-scale collective motions in the filament/motor mixture through hydrodynamic coupling. Synthetic active suspensions made of small numbers of components reveal how higher-order aspects of assembly and organization are built in living cells. These systems also present new challenges to our understanding, design, and analysis of materials, and have the potential to provide valuable new technologies such as autonomously moving and self-healing materials. In this work, the investigators study active cellular matter composed of microtubules and molecular motors through multiscale methods, and tightly coupled modeling, analysis, and simulation. The project aims to understand the fundamental interactions underlying stress generation within bundles of rigid/flexible biofilaments that undergo dynamic instability, as well as the nonlinear dynamics and hierarchical pattern formation in large-scale collective motions. The project will also predict key material properties including its coherent structures, local heterogeneity, time- and length-scales, and material rheology. To resolve the physics at different length- and time-scales, several methods will be developed and integrated: (1) microtubule-motor interactions will be simulated using a kinetic Monte Carlo method; (2) the hydrodynamic interactions between objects of various shapes will be modeled using a nonlocal slender body/boundary integral method, together with fast summation methods; (3) a pseudo-spectral method will be implemented to simulate the collective motion through a continuous active liquid-crystal type model.