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arXiv · 1802.09265

Limited Resources Induce Bistability in Microtubule Length Regulation

Matthias Rank·Aniruddha Mitra·Louis Reese·Stefan Diez·Erwin Frey
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Abstract

The availability of protein is an important factor for the determination of the size of the mitotic spindle. Involved in spindle-size regulation is kinesin-8, a molecular motor and microtubule (MT) depolymerase, which is known to tightly control MT length. Here, we propose and analyze a theoretical model in which kinesin-induced MT depolymerization competes with spontaneous polymerization while supplies of both tubulin and kinesin are limited. In contrast to previous studies where resources were unconstrained, we find that, for a wide range of concentrations, MT length regulation is bistable. We test our predictions by conducting in vitro experiments, and find that the bistable behavior manifests in a bimodal MT length distribution.

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Matthias Rank, Aniruddha Mitra, Louis Reese, Stefan Diez, Erwin Frey. 2018-02-26. Limited Resources Induce Bistability in Microtubule Length Regulation. https://doi.org/10.1103/physrevlett.120.148101

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