The kinesin walk: a dynamic model with elastically coupled heads

Area of Science:

• Biophysics
• Molecular Motors
• Cellular Transport

Background:

• Kinesin is a motor protein crucial for intracellular transport.
• Two-headed kinesin molecules exhibit complex transport properties.
• In vitro motility assays are used to study kinesin behavior.

Purpose of the Study:

• To propose a simple and robust model for the kinesin stepping process.
• To explain the peculiar transport properties of two-headed kinesin.
• To validate the model against experimental data.

Main Methods:

• Development of a model for elastically coupled Brownian heads.
• Analytic and numerical treatment of the proposed model.
• Comparison of model predictions with experimental data for kinesin motility.

Main Results:

• The model successfully replicates observed kinesin transport properties.
• The model shows a very good fit to experimental data with minimal free parameters.
• Parameter variations primarily affect zero-load velocity, aligning with measurements.

Conclusions:

• The proposed model provides a robust explanation for two-headed kinesin behavior.
• The model is consistent with experimental findings on kinesin ATPase pathway.
• This work offers a simplified yet accurate framework for understanding kinesin motor function.