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bioRxiv · 10.1101/780999

Ser/Thr kinase Trc controls neurite outgrowth in Drosophila by modulating microtubule-microtubule sliding

Gelfand, V. I.·Norkett, R.·del Castillo, U.·Lu, W.
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Abstract

Correct neuronal development requires tailored neurite outgrowth. Neurite outgrowth is driven by microtubule sliding - the transport of microtubules along each other. We have recently demonstrated that a \"mitotic\" kinesin-6 (Pavarotti in Drosophila) effectively inhibits microtubule-sliding and neurite outgrowth. However, mechanisms of Pavarotti regulation in interphase cells and specifically in neurite outgrowth are unknown. Here, we use a combination of live imaging and biochemical methods to show that the inhibition of microtubule sliding by Pavarotti is controlled by phosphorylation. We identify the Ser/Thr NDR kinase Tricornered (Trc) as a Pavarotti-dependent regulator of microtubule sliding in neurons. Further, we show that Trc-mediated phosphorylation of Pavarotti promotes its interaction with 14-3-3 proteins. 14-3-3 binding is necessary for Pavarotti to interact with microtubules and inhibit sliding. Thus, we propose a pathway by which microtubule sliding can be up or down regulated in neurons to control neurite outgrowth, and establish parallels between microtubule sliding in mitosis and post-mitotic neurons.

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Gelfand, V. I., Norkett, R., del Castillo, U., Lu, W.. 2019-09-24. Ser/Thr kinase Trc controls neurite outgrowth in Drosophila by modulating microtubule-microtubule sliding. https://doi.org/10.1101/780999

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