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bioRxiv · 10.1101/2024.02.06.579144

Microtubule perturbations of neurite extension and nucleokinesis in an iPSC-derived model system

Sebastien, M.·Paquette, A. L.·Hendricks, A. G.·Brouhard, G. J.
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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 (MAPs), 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 trans-differentiation into the neuronal state (EBiSC-NEUR1 neurons, referred to as NGN2 neurons below). We developed a suite of open-access, semi-automated 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 nucle-okinesis 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.

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Sebastien, M., Paquette, A. L., Hendricks, A. G., Brouhard, G. J.. 2024-02-07. Microtubule perturbations of neurite extension and nucleokinesis in an iPSC-derived model system. https://doi.org/10.1101/2024.02.06.579144

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