Stromule extension along microtubules coordinated with actin-mediated anchoring guides perinuclear chloroplast movement during innate immunity
- University of Delaware, United States
- University of California, Davis, United States
Abstract
Dynamic tubular extensions from chloroplasts called stromules have recently been shown to connect with nuclei and function during innate immunity. We demonstrate that stromules extend along microtubules (MTs) and MT organization directly affects stromule dynamics since stabilization of MTs chemically or genetically increases stromule numbers and length. Although actin filaments (AFs) are not required for stromule extension, they provide anchor points for stromules. Interestingly, there is a strong correlation between the direction of stromules from chloroplasts and the direction of chloroplast movement. Stromule-directed chloroplast movement was observed in steady-state conditions without immune induction, suggesting it is a general function of stromules in epidermal cells. Our results show that MTs and AFs may facilitate perinuclear clustering of chloroplasts during an innate immune response. We propose a model in which stromules extend along MTs and connect to AF anchor points surrounding nuclei, facilitating stromule-directed movement of chloroplasts to nuclei during innate immunity.
Article and author information
Author details
Jeffrey Lewis Caplan
Funding
National Institutes of Health (R01 GM097587)
- Savithramma P Dinesh-Kumar
- Jeffrey Lewis Caplan
National Institutes of Health (P20 GM103446)
- Jeffrey Lewis Caplan
National Institutes of Health (S10 OD016361)
- Jeffrey Lewis Caplan
National Institutes of Health (S10 RR027273)
- Jeffrey Lewis Caplan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Kumar 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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Stromule extension along microtubules coordinated with actin-mediated anchoring guides perinuclear chloroplast movement during innate immunity
eLife 7:e23625.
https://doi.org/10.7554/eLife.23625
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