The role of microtubule movement in bidirectional organelle transport

TL;DR

This study reveals that microtubule movements significantly influence bidirectional organelle transport in cells, challenging the traditional view of static microtubule tracks by demonstrating their dynamic fluctuations contribute to cargo movement.

Contribution

The paper provides the first high-resolution measurement of longitudinal microtubule fluctuations and highlights their role in organelle transport, a novel insight into cytoskeletal dynamics.

Findings

Microtubule fluctuations correlate with organelle movement.

Microtubule oscillations contribute to cargo transport.

Organelle movement involves dynamic microtubule tracks.

Abstract

We study the role of microtubule movement in bidirectional organelle transport in Drosophila S2 cells and show that EGFP-tagged peroxisomes in cells serve as sensitive probes of motor induced, noisy cytoskeletal motions. Multiple peroxisomes move in unison over large time windows and show correlations with microtubule tip positions, indicating rapid microtubule fluctuations in the longitudinal direction. We report the first high-resolution measurement of longitudinal microtubule fluctuations performed by tracing such pairs of co-moving peroxisomes. The resulting picture shows that motor-dependent longitudinal microtubule oscillations contribute significantly to cargo movement along microtubules. Thus, contrary to the conventional view, organelle transport cannot be described solely in terms of cargo movement along stationary microtubule tracks, but instead includes a strong contribution from the movement of the tracks.