A plant chitinase controls cortical infection thread progression and nitrogen-fixing symbiosis
- Aarhus University, Denmark
- University of Copenhagen, Denmark
- The James Hutton Institute, United Kingdom
- Kazusa DNA Research Institute, Japan
- National Agriculture and Food Research Organization, Japan
Abstract
Morphogens provide positional information and their concentration is key to the organized development of multicellular organisms. Nitrogen-fixing root nodules are unique organs induced by Nod factor-producing bacteria. Localized production of Nod factors establishes a developmental field within the root where plant cells are reprogrammed to form infection threads and primordia. We found that regulation of Nod factor levels by Lotus japonicus is required for the formation of nitrogen-fixing organs, determining the fate of this induced developmental program. Our analysis of plant and bacterial mutants shows that a host chitinase modulates Nod factor levels possibly in a structure-dependent manner. In Lotus, this is required for maintaining Nod factor signalling in parallel with the elongation of infection threads within the nodule cortex, while root hair infection and primordia formation are not influenced. Our study shows that infected nodules require balanced levels of Nod factors for completing their transition to functional, nitrogen-fixing organs.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Kasper Røjkjær Andersen
Funding
Danish Reasearch Foundation (DNRF79)
- Anna Malolepszy
- Simon Kelly
- Kasper Kildegaard Sørensen
- Christina Kalisch
- Zoltan Bozsoki
- Michael Panting
- Stig U Andersen
- Dorthe Bødker Jensen
- Maria Vinther
- Noor de Jong
- Lene Heegaard Madsen
- Kira Gysel
- Mette U Berentsen
- Michael Blaise
- Knud Jørgen Jensen
- Mikkel B Thygesen
- Niels Sandal
- Kasper Røjkjær Andersen
- Simona Radutoiu
China Scholarship Council (201604910506)
- Ke Tao
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Malolepszy 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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A plant chitinase controls cortical infection thread progression and nitrogen-fixing symbiosis
eLife 7:e38874.
https://doi.org/10.7554/eLife.38874
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