Effects of Cytoskeletal Network Mesh Size on Cargo Transport

TL;DR

This study investigates how the mesh size of cytoskeletal networks affects cargo transport within cells, combining experiments, theory, and simulations to understand transport efficiency and trajectory behavior.

Contribution

It introduces an experimental method to vary cytoskeletal mesh size and develops an analytical theory and simulations to predict cargo transport properties.

Findings

Transport efficiency varies with mesh size.

Analytical model accurately predicts run length.

Simulations match experimental trajectories.

Abstract

Intracellular transport of cargoes in the cell is essential for the organization and functioning cells, especially those that are large and elongated. The cytoskeletal networks inside large cells can be highly complex, and this cytoskeletal organization can have impacts on the distance and trajectories of travel. Here, we experimentally created microtubule networks with varying mesh sizes and examined the ability of kinesin-driven quantum dot cargoes to traverse the network. Using the experimental data, we deduced parameters for cargo detachment at intersections and away from intersections, allowing us to create an analytical theory for the run length as a function of mesh size. We also used these parameters to perform simulations of cargoes along paths extracted from the experimental networks. We find excellent agreement between the trends in run length, displacement, and trajectory persistence length comparing the experimental and simulated trajectories.