A mathematical model of stress generation in microtubule pair interactions

Microtubules and motor proteins are basic ingredients in many cellular structures and of new biosynthetic ``active'' suspensions. The interaction of microtubules with their surrounding fluid medium depends fundamentally upon the force generation afforded them through cross-linking motile motor proteins. Here we develop a simple mathematical model, based on the statistical mechanics, motor proteins binding and unbinding, to study the generation of active fluid stresses. We study the role and contributions of ``polarity sorting'' and ``tether'' relaxation on the generation of intrinsic, destabilizing stresses.