Abstract
In neurons, patterns of different microtubule types are essential for neurite extension and nucleokinesis. Cellular model systems such as rodent primary cultures and induced pluripotent stem cells (iPSC)-derived neurons have provided key insights into how these patterns are created and maintained through the action of microtubule-associated proteins, motor proteins, and regulatory enzymes. iPSC-derived models show tremendous promise but lack benchmarking and validation relative to rodent primary cultures. Here we have characterized a recent iPSC-derived model, in which doxycycline-induced expression of Neurogenin-2 drives consistent transdifferentiation into the neuronal state (EBiSC-NEUR1 neurons, referred to as NGN2 neurons below). We developed a suite of open-access, semiautomated methods to measure neurite extension and nucleokinesis of NGN2 neurons, which compare favorably to published data from other models. Then, we challenged NGN2 neurons with a panel of drugs that perturb microtubule physiology. NGN2 neurons extension and nucleokinesis were significantly perturbed by two microtubule-targeting drugs, namely a taxane (paclitaxel) and a vinca alkaloid (DZ-2384). In contrast, inhibition of microtubule severing (spastazoline) or of deacetylation (trichostatin A) had a limited effect on nucleokinesis only. Our results support the primary importance of microtubule dynamics in neuronal development and demonstrate the power of NGN2 neurons as a model system.