Active restructuring of cytoskeleton composites leads to increased mechanical stiffness, memory, and heterogeneity

  title={Active restructuring of cytoskeleton composites leads to increased mechanical stiffness, memory, and heterogeneity},
  author={Janet Y Sheung and Daisy H. Achiriloaie and Karthik Reddy Peddireddy and Gloria Lee and Michael J Rust and Moumita Das and Jennifer L. Ross and Rae M. Robertson-Anderson},
The composite cytoskeleton, comprising interacting networks of semiflexible actin and rigid microtubules, actively generates forces and restructures using motor proteins such as myosins to enable key mechanical processes including cell motility and mitosis. Yet, how motor-driven activity alters the mechanics of cytoskeleton composites remains an open challenge. Here, we perform optical tweezers microrheology on actin-microtubule composites driven by myosin II motors to show that motor activity… 
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