Centrosome reorientation in wound-edge cells is cell type specific

Area of Science:

• Cell Biology
• Cytoskeleton Dynamics
• Cell Migration Mechanisms

Background:

• Cell migration is crucial for development and wound healing.
• The microtubule organizing center (MTOC) plays a key role in directing cell movement.
• Understanding MTOC reorientation provides insights into cell motility.

Purpose of the Study:

• To directly observe and compare MTOC reorientation during cell migration in different cell lines.
• To investigate the molecular mechanisms and microtubule dynamics involved in MTOC repositioning.
• To determine if MTOC reorientation is essential for directed cell migration.

Main Methods:

• Live-cell imaging of fluorescently tagged gamma-tubulin in CHO and PtK cells during wound healing.
• Analysis of centrosome and nucleus movement rates and stochasticity.
• Assessment of microtubule dynamics using photoactivated caged tubulin.
• Perturbation of cell adhesion and assessment of MTOC reorientation.

Main Results:

• CHO cells reoriented their centrosomes forward of the nucleus; PtK cells showed centrosome lagging.
• Centrosome motion was stochastic in both cell types, with differing relative speeds to the nucleus.
• CHO cell MTOC reorientation required dynamic microtubules and dynein/dynactin, and was sensitive to adhesion changes.
• Microtubules were transported directionally, but with more coherent movement in CHO cells compared to PtK cells.

Conclusions:

• Centrosome reorientation is not universally required for directed cell migration.
• Diverse cell types employ distinct mechanisms for microtubule array remodeling during migration.
• Cell adhesion plays a significant role in regulating MTOC positioning and cell migration.