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bioRxiv · 10.1101/2021.06.23.449589

A live-cell marker to visualize the dynamics of stable microtubules

Jansen, K. I.·Burute, M.·Kapitein, L. C.
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Abstract

The microtubule (MT) cytoskeleton underlies processes such as intracellular transport and cell division. Immunolabeling for post-translational modifications of tubulin has revealed the presence of different MT subsets, which are believed to differ in stability and function. Whereas dynamic MTs can readily be studied using live-cell plus-end markers, the dynamics of stable MTs have remained obscure due to a lack of tools to directly visualize these MTs in living cells. Here, we present a live-cell marker to visualize stable MTs and explore their dynamics. We demonstrate that a rigor mutant of kinesin-1 binds selectively to acetylated MTs without affecting MT organization and organelle transport. These MTs are long-lived, do not depolymerize upon nocadozale-treatment or laser-based severing, and display rich dynamics, including undulation, looping and sliding. This marker will help to explore how different MT subsets contribute to cellular organization and transport.

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Jansen, K. I., Burute, M., Kapitein, L. C.. 2021-06-23. A live-cell marker to visualize the dynamics of stable microtubules. https://doi.org/10.1101/2021.06.23.449589

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