Coordination of two opposite flagella allows high-speed swimming and active turning of individual zoospores
- Institut Jacques Monod, France
- Université Côte d'Azur, France
- CY Cergy Paris Université, France
Abstract
Phytophthora species cause diseases in a large variety of plants and represent a serious agricultural threat, leading, every year, to multibillion dollar losses. Infection occurs when these biflagellated zoospores move across the soil at their characteristic high speed and reach the roots of a host plant. Despite the relevance of zoospore spreading in the epidemics of plant diseases, characteristics of individual swimming of zoospores have not been fully investigated. It remains unknown about the characteristics of two opposite beating flagella during translation and turning, and the roles of each flagellum on zoospore swimming. Here, combining experiments and modeling, we show how these two flagella contribute to generate thrust when beating together, and identify the mastigonemes-attached anterior flagellum as the main source of thrust. Furthermore, we find that turning involves a complex active process, in which the posterior flagellum temporarily stops, while the anterior flagellum keeps on beating and changes its gait from sinusoidal waves to power and recovery strokes, similar to Chlamydomonas's breaststroke, to reorient its body to a new direction. Our study is a fundamental step towards a better understanding of the spreading of plant pathogens' motile forms, and shows that the motility pattern of these biflagellated zoospores represents a distinct eukaryotic version of the celebrated 'run-and-tumble' motility class exhibited by peritrichous bacteria.
Data availability
All data generated and simulation files are available via Zenodo using this URL: https://doi.org/10.5281/zenodo.4710633. In the data, we include:(1) datasets of all zoospore positions along multiple trajectories in the experiment of Figure 2,(2) a MATLAB file to compute all the statistical results in Figure 2(D-G),(3) a MATLAB file containing the simulation model presented in Figure 2(H),(4) datasets of zoospore positions, speed, moving directions, body orientations during the turning, presented in Figure 4(A-D).
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Cooperation of two opposite flagella allows high-speed swimming and active turning in zoosporesZenodo, doi.org/10.5281/zenodo.4710633.
Article and author information
Author details
Funding
Centre National de la Recherche Scientifique (ANR-15-IDEX-01)
- Eric Galiana
- Xavier Noblin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Tran 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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Coordination of two opposite flagella allows high-speed swimming and active turning of individual zoospores
eLife 11:e71227.
https://doi.org/10.7554/eLife.71227
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