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bioRxiv · 10.1101/2021.07.23.453475

Regulation of neuronal progenitor delamination by dynein-driven post-Golgi apical transport

Brault, J.-B.·Bardin, S.·Lampic, M.·Carpentieri, J.·Coquand, L.·Penisson, M.·Lachuer, H.·Victoria, G. S.·Baloul, S.·Boncompain, G.·Miserey-Lenkei, S.·Fraisier, V.·Francis, F.·Perez, F.·Goud, B.·Baffet, A. D.
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Abstract

Radial glial (RG) cells are the neural stem cells of the developing neocortex. Apical RG (aRG) cells can delaminate to generate basal RG (bRG) cells, a cell type associated with human brain expansion. Here, we report that this delamination is regulated by the post-Golgi secretory pathway. Using in situ subcellular live imaging, we show that post-Golgi transport of RAB6+ vesicles occurs toward the minus ends of microtubules and depends on dynein. We demonstrate that the apical determinant Crumbs3 (CRB3) is also transported by dynein. Double knockout of RAB6A/A and RAB6B impairs apical localization of CRB3, and induces a retraction of aRG cell apical process, leading to delamination and ectopic division. These defects are phenocopied by knock-out of the dynein activator LIS1. Overall, our results identify a RAB6-dynein-LIS1 complex for Golgi to apical surface transport in aRG cells, and highlights the role of this pathway in the maintenance of neuroepithelial integrity.

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Brault, J.-B., Bardin, S., Lampic, M., Carpentieri, J., Coquand, L., Penisson, M., Lachuer, H., Victoria, G. S., Baloul, S., Boncompain, G., Miserey-Lenkei, S., Fraisier, V., Francis, F., Perez, F., Goud, B., Baffet, A. D.. 2021-07-24. Regulation of neuronal progenitor delamination by dynein-driven post-Golgi apical transport. https://doi.org/10.1101/2021.07.23.453475

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