Microtubules are one of the three kinds of cytoskeleton components. They are macromolecules with about 13 protofilaments formed with the ab-tublin dimers. Microtubules play important roles in many eukaryotic cellular processes, including intracellular transporting, cell motility, meiosis and mitosis. According to the widely accepted textbook mechanism, during the assembly process the ab-tublin dimers add onto the growing end of a microtubule one by one. However, Some experimental observations challenge this conventional view. This alternative model proposes that tublins first form a two-dimensional open sheet, which in turn closes into tubes. Cryo-EM studies show that within the two-dimensional sheet structure, two types of lateral interactions alternate between neighboring protofilaments.
Collaborating with the Nogales group at UC Berkeley, we are using various modeling tools to understand the microtubule assembly process.