Study Of Mechanical Properties Of Structure Of Microtubule Depolymerization

Microtubules as main component of the cytoskeleton have a dynamic instability characteristic, which often has been in a random variation between polymerization to grow or depolymerization to shorten. This characteristic is very important biological significance, such as speculation that during eukaryotic cells mitosis, the main power that drives the sister chromosome separation into two daughter cells, comes from this characteristic. This is because the depolymerization of microtubule can produce mechanical force, with the aid of related molecular structure can drive the chromosome separation. Around this conjecture, there are many groups had measured the force produced by the depolymerizing microtubule, and established a preliminary theoretical model that reveals how the force production by depolymerizing microtubule to drive the chromosome separation. However, these studies are still not enough to accurately and quantitatively reveal the biomechanical mechanism of depolymerizing microtubule driving the chromosome separation. In view of this, our dissertation by considering the intermolecular interaction potential of microtubule and basing on large deformation continuous curved beam theory to study the mechanical properties of microtubule structure that after depolymerization, founded a new quantitative biomechanical mechanism that depolymerizing microtubules drive the chromosome separation. Research results:(1) Establish the microtubules and Dam1 nanometer composite structure of the specific theoretical connection model;(2) Analysis the force production by depolymerizing microtubule;(3) The result of the force production by depolymerizing microtubule in our theoretical calculation in conformity with the experimental measurement, proposes a new mechanisms that depolymerizing microtubule drive chromosome separation at mitosis anaphase.This study got a precise mechanics model of protofilament after microtubule depolymerization, not only deepen the people to understand the mechanical properties of depolymerizing microtubule while provide theoretical reference for experimental measurement of microtubule structure after the depolymerization.