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arXiv · 1902.07904

Filamentous Active Matter: Band Formation, Bending, Buckling, and Defects

Gerrit Vliegenthart·Arvind Ravichandran·Marisol Ripoll·Thorsten Auth·Gerhard Gompper
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Abstract

Motor proteins drive persistent motion and self-organisation of cytoskeletal filaments. However, state-of-the-art microscopy techniques and continuum modelling approaches focus on large length and time scales. Here, we perform component-based computer simulations of polar filaments and molecular motors linking microscopic interactions and activity to self-organisation and dynamics from the two-filament level up to the mesoscopic domain level. Dynamic filament crosslinking and sliding, and excluded-volume interactions promote formation of bundles at small densities, and of active polar nematics at high densities. A buckling-type instability sets the size of polar domains and the density of topological defects. We predict a universal scaling of the active diffusion coefficient and the domain size with activity, and its dependence on parameters like motor concentration and filament persistence length. Our results provide a microscopic understanding of cytoplasmic streaming in cells and help to develop design strategies for novel engineered active materials.

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Gerrit Vliegenthart, Arvind Ravichandran, Marisol Ripoll, Thorsten Auth, Gerhard Gompper. 2019-02-21. Filamentous Active Matter: Band Formation, Bending, Buckling, and Defects. https://doi.org/10.1126/sciadv.aaw9975

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