Which phase in microtubule dynamics involves sudden rapid depolymerization?
Dynamic instability coined by Mitchison and Kirschner describes microtubule switching without intermediate steady state enabling rapid reorganization. Four parameters define behavior: growth rate shrinkage rate catastrophe frequency rescue frequency. Growth corresponds to net addition of GTP tubulin maintaining cap of a few layers. Catastrophe is stochastic abrupt switch from growth to rapid shrinkage where depolymerization proceeds at about 20 microns per minute protofilaments curl outward releasing dimers. Rescue reverse switches shrinkage to growth via capture of GTP islands remaining in la
Ref: Mitchison & Kirschner, Nature 1984 – Catastrophe phase sudden rapid depolymerization in dynamic instability.
