Random bursts determine dynamics of active filaments

Area of Science:

• Physics
• Biophysics
• Statistical Mechanics

Background:

• Active matter systems possess local energy, preventing thermal equilibrium.
• Fluctuating active systems display statistical properties distinct from equilibrium systems.
• Understanding nonthermal distributions is key to characterizing active matter behavior.

Purpose of the Study:

• Investigate the emergence of nonthermal distributions in active matter.
• Utilize the actin filament gliding assay as a model system.
• Elucidate the fundamental mechanisms driving these nonequilibrium phenomena.

Main Methods:

• Employing the actin filament gliding assay.
• Analyzing energy injection and dissipation dynamics.
• Utilizing stochastic computer simulations and kinetic modeling.

Main Results:

• Demonstrated interplay between local energy injection and nonequilibrium dissipation.
• Observed emergence of nonthermal filament curvature distributions.
• Showcased non-Gaussian shape of curvature statistics.

Conclusions:

• The mechanism involves energy injection analogous to a heat bath and dynamic variable jumps.
• Nonthermal distributions arise from the coupling of energy dynamics and dissipation.
• Simulations and models quantitatively reproduce experimental findings on filament curvature and dynamics.