Microtubule dynamics were processed using ImageJ software. A custom JavaScript was used to create and analyze kymographs, showing microtubule length over time, to extract growth rates and catastrophe frequencies. Only the faster-growing, so called "plus"-ends of microtubules were analyzed. Growth rates were measured as the slopes on the kymographs, while catastrophe frequencies were defined as the number of growth-to-shortening transitions per growth interval.