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Dynamic instability of microtubules: effect of catastrophe-suppressing drugs

Pankaj Kumar Mishra·Ambarish Kunwar·Sutapa Mukherji·Debashish Chowdhury
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Abstract

Microtubules are stiff filamentary proteins that constitute an important component of the cytoskeleton of cells. These are known to exhibit a dynamic instability. A steadily growing microtubule can suddenly start depolymerizing very rapidly; this phenomenon is known as ``catastrophe''. However, often a shrinking microtubule is ``rescued'' and starts polymerizing again. Here we develope a model for the polymerization-depolymerization dynamics of microtubules in the presence of {\it catastrophe-suppressing drugs}. Solving the dynamical equations in the steady-state, we derive exact analytical expressions for the length distributions of the microtubules tipped with drug-bound tubulin subunits as well as those of the microtubules, in the growing and shrinking phases, tipped with drug-free pure tubulin subunits. We also examine the stability of the steady-state solutions.

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BibTeXRIS

Pankaj Kumar Mishra, Ambarish Kunwar, Sutapa Mukherji, Debashish Chowdhury. 2007-02-21. Dynamic instability of microtubules: effect of catastrophe-suppressing drugs. https://doi.org/10.1103/physreve.72.051914

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