A5: Mesoscopic models of cytoskeletal rheology
Collaborating PIs: Helmut Grubmüller, Andreas Janshoff, Sarah Köster, Stefan Klumpp, Anne Wald
Overarching research question: How can we construct mesoscopic models of cytoskeletal rheology that explicitly account for heterogeneity and active processes?
The aim of this project is to construct mesoscopic models of cytoskeletal rheology that explicitly account for heterogeneity and active processes. This allows us to go beyond the phenomenological application of models developed for passive materials, and produce new insights into the physical origins of low-frequency power-law rheology in the cytoskeleton. Starting from models for passive disordered materials (soft glassy rheology) we include explicit active mechanisms such as detachment and sliding of motors along filaments. Next local filament rheology and the effect of passive and active cross-linkers are included. For heterogeneity on larger length scales we then incorporate also variability in filament length and thickness, including bundling effects. We generally aim for models where analytical predictions can be extracted, at least in scaling (e.g. low frequency) limits, supplemented as necessary by numerical solutions or approximations that will be verified using stochastic simulations.
Core field: theoretical physics/mathematics
PhD training objectives: model construction (mesoscopic models, disorder, active SGR, test filament approaches, effective medium method, cavity theory etc.); model evaluation (numerical solutions or stochastic simulation for linear and nonlinear rheology, scaling limits for low frequency); analysis and fitting to experimental data (including familiarity with experimental accuracy and potential limitations).