The random release of phosphate controls the dynamic instability of microtubules

TL;DR

This paper presents a stochastic biochemical model that explains microtubule dynamic instability, accurately predicting key behaviors like catastrophe times and cap size, and offers an analytical framework for further research.

Contribution

The model explicitly incorporates phosphate release and biochemical processes, providing a microscopic understanding of microtubule instability not previously achieved.

Findings

Predicts catastrophe times and delay after dilution

Quantitatively describes cap size dynamics

Provides an analytically solvable framework

Abstract

A simple stochastic model which describes microtubule dynamics and explicitly takes into account the relevant biochemical processes is presented. The model incorporates binding and unbinding of monomers and random phosphate release inside the polymer. It is shown that this theoretical approach provides a microscopic picture of the dynamic instability phenomena of microtubules. The cap size, the concentration dependence of the catastrophe times and the delay before observing catastrophes following a dilution can be quantitatively predicted by this approach in a direct and simple way. Furthermore, the model can be solved analytically to a large extend, thus offering a valuable starting point for more refined studies of microtubules dynamics.