Eric Keaveny: Nonlinear and collective dynamics of active filaments

Abstract:

In many biological contexts, fluid motion in and around cells is driven by motor proteins moving along and exerting forces on flexible biofilaments, such as microtubules. This occurs, for instance, in phenomena such as cytoplasmic streaming and cilia beating. In this talk, I will discuss the follower force model – a simple model that describes motor protein-driven filaments – and describe the numerical methods that we use to compute resulting filament dynamics. Using our computational framework alongside a Jacobian-Free Newton Krylov solver, we examine in detail the different states that emerge in the model (whirling, beating, quasi-periodic dynamics) as we vary the follower force strength, and classify the bifurcations that give rise to these states. In the last part of the talk, we will examine how the interactions between filaments lead to different coordinated states and explore how the underlying surface (topology and ability to move) affect the coordinated state.