The goal of this proposal is to elucidate the behavior of active matter at length scales ranging from microscopic to macroscopic, using an interdisciplinary approach involving both physics and biology. The materials unifying all of the experiments are filamentous microtubules and kinesins, which are molecular motors that use ATP hydrolysis to propel themselves along the microtubule tracks and thus drive the assembly toward non-equilibrium active states. The project will specifically develop three model systems of active matter. First, a “bottom up” approach will be used to determine the minimal system, consisting of microtubules, active motors and passive cross-linkers, required to create a self-oscillating active bundle. Second, a complementary “top down” approach will be used to deconstruct a fully functional axoneme and determine the minimal set of structural components required for its active beating. This effort will involve a combination of genetic, ultra-structural and biophysical methods. Third, active nematic liquid crystals will be assembled and characterized both for microscopic dynamics and behavior at continuum length scales.