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bioRxiv · 10.1101/356642

Vimentin filaments interact with the mitotic cortex allowing normal cell division

Abstract

The vimentin network displays remarkable plasticity to support basic cellular functions. Here, we show that in several cell types vimentin filaments redistribute to the cell periphery during mitosis, forming a robust scaffold interwoven with cortical actin and affecting the mitotic cortex properties. Importantly, the intrinsically disordered tail domain of vimentin is essential for this redistribution, which allows normal mitotic progression. A tailless vimentin mutant forms curly bundles, which remain entangled with dividing chromosomes leading to mitotic catastrophes or asymmetric partitions. Serial deletions of the tail domain induce increasing impairments of cortical association and mitosis progression. Disruption of actin, but not of microtubules, mimics the impact of tail deletion. Pathophysiological stimuli, including HIV-protease and lipoxidation, induce similar alterations. Interestingly, filament integrity is dispensable for cortical association, which also occurs in vimentin particles. These results unveil novel implications of vimentin dynamics in cell division by means of its interplay with the mitotic cortex.

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Duarte, S., Viedma-Poyatos, A., Navarro-Carrasco, E., Martinez, A. E., Pajares, M. A., Perez-Sala, D.. 2018-06-27. Vimentin filaments interact with the mitotic cortex allowing normal cell division. https://doi.org/10.1101/356642

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