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bioRxiv · 10.1101/2021.08.11.455966

Rab11 endosomes coordinate centrosome number and movement following mitotic exit

Abstract

The last stage of cell division involves two daughter cells remaining interconnected by a cytokinetic bridge that is cleaved in a process called abscission. During pre-abscission, we identified that the centrosome moves in a Rab11-dependent manner towards the cytokinetic bridge in human cells grown in culture and in an in vivo vertebrate model, Danio rerio (zebrafish). Rab11-endosomes are dynamically organized in a Rab11-GTP dependent manner at the centrosome during pre-abscission and this organization is required for the centrosome protein, pericentrin, to be enriched at the centrosome. Using zebrafish embryos, we found that reduction in pericentrin expression or optogenetically disrupting Rab11-endosome function inhibited centrosome movement towards the cytokinetic bridge and abscission resulting in daughter cells prone to being binucleated and/or having supernumerary centrosomes. These studies suggest that Rab11-endosomes contribute to centrosome function during pre-abscission by regulating pericentrin organization resulting in appropriate centrosome movement towards the cytokinetic bridge and subsequent abscission.

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BibTeXRIS

Krishnan, N., Swoger, M., Bates, M., Freshour, J., Fioramonti, P., Patteson, A. E., Hehnly, H.. 2021-08-11. Rab11 endosomes coordinate centrosome number and movement following mitotic exit. https://doi.org/10.1101/2021.08.11.455966

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