Rheological and Thermal Behaviour of Microtubule Networks Mediated by Microtubule Associated Proteins

Abstract

Microtubules are dynamic polymers crucial for cell division, intracellular transport, and motility. The regulation of microtubule dynamics and network formation is mediated by microtubule-associated proteins (MAPs). This study systematically investigates the effects of MAP2, MAP4, and tau in microtubule network formation and their rheological behavior. Using fluorescence microscopy, dynamic viscoelasticity measurements, and dynamic light scattering (DLS), we examine how these MAPs affect microtubule network structure and mechanical properties across various temperatures. Our findings show that MAP2 induces the formation of aggregates and flexible microtubule bundles; tau, on the other hand, promotes the formation of stiff, cross-linked microtubule networks indicating increased rigidity, while MAP4 promotes bundle formation. DLS measurements further reveal distinct relaxation modes depending on the type of MAP present. These results enhance our understanding of microtubule behavior in cellular environments and have significant implications for manipulating its properties for therapeutic purposes, potentially aiding in treating diseases related to cytoskeletal dysfunction.