Motor crosslinking augments elasticity in active nematics.

Area of Science:

• Soft Matter Physics
• Biophysics
• Materials Science

Background:

• Active materials generate flows from internal stresses.
• Understanding mesoscopic behavior dependence on microscopic properties is crucial.
• Knowledge gap exists in relating hydrodynamic parameters to microscopic element properties.

Purpose of the Study:

• To connect the structure and dynamics of active nematics to their microscopic properties.
• To investigate the role of motor processivity, speed, and valency.
• To elucidate how microscopic features influence macroscopic behavior.

Main Methods:

• Combined experimental approaches with multiscale modeling.
• Studied active nematics composed of biopolymer filaments and molecular motors.
• Varied motor kinetics and passive filament crosslinking.

Main Results:

• Filament crosslinking by motors and passive agents dominates over excluded volume effects on nematic elasticity.
• Motor speed and crosslinking exhibit a competitive, non-monotonic relationship with nematic flow.
• Passive filament crosslinking significantly dictates energy transfer into nematic flow.

Conclusions:

• Motor proteins are key in both generating activity and contributing to nematic elasticity.
• Microscopic properties critically influence the emergent hydrodynamic and elastic behaviors of active nematics.
• Findings offer insights for the rational engineering of active materials.