A Dynamic Escape Problem of Molecular Motors

Area of Science:

• Biophysics
• Molecular Biology
• Biomechanical Engineering

Background:

• Skeletal muscle exhibits unique behavior near stall forces, where myosin proteins struggle to bind actin.
• Myosin-V utilizes thermal agitation to enhance force production and reach, suggesting a broader principle for molecular motors.

Purpose of the Study:

• To explore the dynamics of a molecular motor model incorporating Brownian motion.
• To demonstrate how thermal agitation can be harvested for mechanical work in molecular machinery.
• To investigate a model that overcomes limitations of simple attractive forces and rate functions.

Main Methods:

• A spatially two-dimensional mechanical model was revisited to simulate molecular motor dynamics.
• The model incorporates Brownian motion and variable lattice spacing.
• It avoids rate functions and empirically inspired spatial potential functions.

Main Results:

• Thermal agitation can be harvested for useful mechanical work by molecular motors.
• The model illustrates overcoming local elastic energy well boundaries.
• Variable lattice spacing is accommodated, allowing for potential misalignment of myosin II with actin.

Conclusions:

• Thermal motion is a viable mechanism for molecular motors to perform mechanical work.
• The model provides a foundation for designing artificial molecular-scale motors.
• This approach offers insights into biomechanical phenomena without relying on complex potential functions.