Molecular organization and mechanics of single vimentin filaments revealed by super-resolution imaging

Vicente, F. N.; Lelek, M.; Tinevez, J.-Y.; Tran, Q. D.; Pehau-Arnaudet, G.; Zimmer, C.; Etienne-Manneville, S.; Giannone, G.; Leduc, C.

doi:10.1101/2021.09.07.459174

bioRxiv · 10.1101/2021.09.07.459174

Molecular organization and mechanics of single vimentin filaments revealed by super-resolution imaging

Vicente, F. N.·Lelek, M.·Tinevez, J.-Y.·Tran, Q. D.·Pehau-Arnaudet, G.·Zimmer, C.·Etienne-Manneville, S.·Giannone, G.·Leduc, C.

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Abstract

Intermediate filaments (IF) are involved in key cellular functions including polarization, migration, and protection against large deformations. These functions are related to their remarkable ability to extend without breaking, a capacity that should be determined by the molecular organization of subunits within filaments. However, this structure-mechanics relationship remains poorly understood at the molecular level. Here, using super-resolution microscopy (SRM), we show that vimentin filaments exhibit a ~49 nm axial repeat both in cells and in vitro. As unit-length-filaments (ULFs) were measured at ~59 nm, this demonstrates a partial overlap of ULFs during filament assembly. Using an SRM-compatible stretching device, we also provide evidence that the extensibility of vimentin is due to the unfolding of its subunits and not to their sliding, thus establishing a direct link between the structural organization and its mechanical properties. Overall, our results pave the way for future studies of IF assembly, mechanical and structural properties in cells.

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Vicente, F. N., Lelek, M., Tinevez, J.-Y., Tran, Q. D., Pehau-Arnaudet, G., Zimmer, C., Etienne-Manneville, S., Giannone, G., Leduc, C.. 2021-09-07. Molecular organization and mechanics of single vimentin filaments revealed by super-resolution imaging. https://doi.org/10.1101/2021.09.07.459174

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