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.
Bibliographical noteFunding Information:
This study was supported by NIH grant P01GM096971 (to G.D. and R.G.), CPRIT recruitment award R1225 (to G.D.), and fellowships from the Swiss National Science Foundation and the Novartis Research Foundation (to C.J.B.). We thank the Live Cell Imaging Core Facility at the University of Texas Southwestern Medical Center and the Nikon Imaging Centers at Harvard Medical School and Northwestern University for help with light microscopy, and we thank the Dana Farber Cancer Institute Flow Cytometry core for help with cell sorting. Research reported in this publication was supported by the National Cancer Institute of the NIH under award number 5P30CA142543. We thank Xiao Ma, UTSW, for help with the double-blind analysis of single cell migration.