Structural state recognition facilitates tip tracking of EB1 at growing microtubule ends
- University of Minnesota, United States
- Vanderbilt University, United States
Abstract
The microtubule binding protein EB1 specifically targets the growing ends of microtubules in cells, where EB1 facilitates the interactions of cellular proteins with microtubule plus-ends. Microtubule end targeting of EB1 has been attributed to high affinity binding of EB1 to GTP-tubulin that is present at growing microtubule ends. However, our 3D single-molecule diffusion simulations predicted a ~6000% increase in EB1 arrivals to open, tapered microtubule tip structures relative to closed lattice conformations. Using quantitative fluorescence, single-molecule, and electron microscopy experiments, we found that the binding of EB1 onto opened, structurally disrupted microtubules was dramatically increased relative to closed, intact microtubules, regardless of hydrolysis state. Correspondingly, in cells, the blunting of growing microtubule plus-ends by Vinblastine was correlated with reduced EB1 targeting. Together, our results suggest that microtubule structural recognition, based on a fundamental diffusion-limited binding model, facilitates the tip tracking of EB1 at growing microtubule ends.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
National Institutes of Health (R01-GM103833)
- Melissa K Gardner
National Institutes of Health (R35-GM126974)
- Melissa K Gardner
National Science Foundation (1350741)
- Melissa K Gardner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Reid et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structural state recognition facilitates tip tracking of EB1 at growing microtubule ends
eLife 8:e48117.
https://doi.org/10.7554/eLife.48117
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