Collective dynamics of kinesin

Area of Science:

• Biophysics
• Cell Biology
• Molecular Motors

Background:

• Motor proteins like kinesin-1 convert chemical energy into mechanical work, crucial for intracellular transport.
• Kinesin-1 moves along microtubules, but its collective behavior in cellular transport remains incompletely understood.
• Existing models often focus on single-motor steady-state dynamics, neglecting transient and collective effects.

Purpose of the Study:

• To develop a mechanistic model for kinesin-1 that describes both transient and steady-state dynamics.
• To simulate the collective behavior of multiple kinesin motors under various conditions.
• To analyze motor coordination and synchronization during cargo transport.

Main Methods:

• A mechanistic model was created, representing each kinesin domain with mechanical potentials linked to chemical kinetics.
• Simulations were performed for coupled kinesin motors with varying loads, linker stiffnesses, and motor numbers.
• Novel metrics were developed to analyze the synchronization of nonlinear, nonsmooth oscillators (kinesin motors).

Main Results:

• Under low loads, coupled kinesin motors exhibit loosely correlated dynamics.
• Increased load leads to enhanced motor correlation, improving force generation capabilities.
• Transporting larger numbers of motors does not significantly increase trajectory dimensionality, indicating high correlation without full synchronization.

Conclusions:

• The proposed model accurately captures transient and steady-state dynamics of kinesin motors.
• Motor coordination is load-dependent, with increased correlation enabling efficient force production under stress.
• Cells can utilize large numbers of kinesin motors for coordinated transport without requiring complete synchronization.