A3: Cooperative molecular motors as active cross-linkers that shape cytoskeletal network structure

Lead PI: Stefan Klumpp
Collaborating PIs: Helmut Grubmüller, Sarah Köster, Peter Lénárt, Tim Salditt, Peter Sollich, Claudia Steinem
Overarching research question: How does tunable processivity emerge in assemblies of non-processive molecular motors and how does it shape the structure of cytoskeletal networks?

The properties of cytoskeletal networks depend on the properties of the filaments themselves and on their interactions that are often mediated by crosslinkers and molecular motors. We focus on the structure and mechanics of multicomponent cytoskeletal networks, i.e. networks consisting of two (or three) filament types. We will combine analytical and simulation approaches to study how the impressive non-linear elasticity of individual intermediate filaments influences the mechanical properties of a network, and how they interact with the actin network and its contractile activity that is powered by myosin motors. We plan to investigate the network structure, the microrheologal properties and the responses to global mechanical perturbations. Models will be developed in close contact with the experimental groups in the RTG.

Core field: theoretical physics/mathematics
PhD training objectives: model development; simulations (stochastic kinetics, Monte Carlo, Langevin dynamics); theoretical methods (stochastic dynamics, nonequilibrium statistical physics); data analysis (simulation, theory-based inference from experimental data).