Vimentin Intermediate Filaments Template Microtubule Networks to Enhance Persistence in Cell Polarity and Directed Migration

Increased expression of vimentin intermediate filaments (VIFs) enhances directed cell migration, but the mechanism behind VIFs’ effect on motility is not understood. VIFs interact with microtubules, whose organization contributes to polarity maintenance in migrating cells. Here, we characterize the dynamic coordination of VIF and microtubule networks in wounded monolayers of retinal pigment epithelial cells. By genome editing, we fluorescently labeled endogenous vimentin and α-tubulin, and we developed computational image analysis to delineate architecture and interactions of the two networks. Our results show that VIFs assemble an ultrastructural copy of the previously polarized microtubule network. Because the VIF network is long-lived compared to the microtubule network, VIFs template future microtubule growth along previous microtubule tracks, thus providing a feedback mechanism that maintains cell polarity. VIF knockdown prevents cells from polarizing and migrating properly during wound healing. We suggest that VIFs’ templating function establishes a memory in microtubule organization that enhances persistence in cell polarization in general and migration in particular. [Display omitted] •Endogenous vimentin and α-tubulin were fluorescently labeled by genome editing•Vimentin-microtubule interactions were analyzed by quantitative live-cell imaging•Vimentin is a template for microtubule organization•Vimentin’s templating function stabilizes cell polarity during directed migration Quantitative live-cell imaging of genome-edited cells shows that, during directed cell migration, vimentin intermediate filaments assemble in an ultrastructural copy of the polarized microtubule network. Because vimentin turns over slower than microtubules, it stabilizes and templates microtubule organization, thus providing persistence to existing cell polarity.