title: Microtubule dynamic instability: a new model with coupled GTP hydrolysis and multistep catastrophe.
abstract: A key question in understanding microtubule dynamics is how GTP hydrolysis leads to catastrophe, the switch from slow growth to rapid shrinkage. We first provide a review of the experimental and modeling literature, and then present a new model of microtubule dynamics. We demonstrate that vectorial, random, and coupled hydrolysis mechanisms are not consistent with the dependence of catastrophe on tubulin concentration and show that, although single-protofilament models can explain many features of dynamics, they do not describe catastrophe as a multistep process. Finally, we present a new combined (coupled plus random hydrolysis) multiple-protofilament model that is a simple, analytically solvable generalization of a single-protofilament model. This model accounts for the observed lifetimes of growing microtubules, the delay to catastrophe following dilution and describes catastrophe as a multistep process.
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
authors.forename: Hugo
authors.initials: H
authors.lastname: Bowne-Anderson
authors.forename: Marija
authors.initials: M
authors.lastname: Zanic
authors.forename: Monika
authors.initials: M
authors.lastname: Kauer
authors.forename: Jonathon
authors.initials: J
authors.lastname: Howard
mesh_terms: D006160:Guanosine Triphosphate / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007700:Kinetics; D008870:Microtubules / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D009010:Monte Carlo Method; D013816:Thermodynamics; D014404:Tubulin / Q000737:chemistry* / Q000378:metabolism
chemical_list: D014404:Tubulin; D006160:Guanosine Triphosphate