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Dynamics of Microtubule Instabilities

T. Antal·P. L. Krapivsky·S. Redner
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Abstract

We investigate the dynamics of an idealized model of microtubule growth that evolves by: (i) attachment of guanosine triphosphate (GTP) at rate lambda, (ii) conversion of GTP to guanosine diphosphate (GDP) at rate 1, and (iii) detachment of GDP at rate mu. As a function of these rates, a microtubule can grow steadily or its length can fluctuate wildly. For mu=0, we find the exact tubule and GTP cap length distributions, and power-law length distributions of GTP and GDP islands. For mu=infinity, we argue that the time between catastrophes, where the microtubule shrinks to zero length, scales as exp(lambda). We also find the phase boundary between a growing and shrinking microtubule.

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T. Antal, P. L. Krapivsky, S. Redner. 2010-11-23. Dynamics of Microtubule Instabilities. https://doi.org/10.1088/1742-5468%2F2007%2F05%2Fl05004

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