Lipid transfer from plants to arbuscular mycorrhiza fungi
- LMU Munich, Biocenter Martinsried, Germany
- University of Cologne Biocenter, Germany
- Technical University Munich, Germany
- University of Bonn, Germany
- Unité Mixte de Recherche 5546, France
- University of Tübingen, Germany
- Norwich Research Park, United Kingdom
Abstract
Arbuscular mycorrhiza (AM) symbioses contribute to global carbon cycles as plant hosts divert up to 20% of photosynthate to the obligate biotrophic fungi. Previous studies suggested carbohydrates as the only form of carbon transferred to the fungi. However, de novo fatty acid (FA) synthesis has not been observed in AM fungi in absence of the plant. In a forward genetic approach, we identified two Lotus japonicus mutants defective in AM-specific paralogs of lipid biosynthesis genes (KASI and GPAT6). These mutants perturb fungal development and accumulation of emblematic fungal 16:1ω5 FAs. Using isotopolog profiling we demonstrate that 13C patterns of fungal FAs recapitulate those of wild-type hosts, indicating cross-kingdom lipid transfer from plants to fungi. This transfer of labelled FAs was not observed for the AM-specific lipid biosynthesis mutants. Thus, growth and development of beneficial AM fungi is not only fueled by sugars but depends on lipid transfer from plant hosts.
Article and author information
Author details
Pierre-Marc Delaux
Funding
Deutsche Forschungsgemeinschaft (SFB924 B03 Function of the GRAS protein RAM1 in arbuscule development)
- Caroline Gutjahr
Deutsche Forschungsgemeinschaft (Emmy Noether program GU1423/1-1)
- Caroline Gutjahr
Deutsche Forschungsgemeinschaft (PA493/7-1 Plant genes required for arbuscular mycorrhiza symbiosis)
- Martin Parniske
Deutsche Forschungsgemeinschaft (SFB924 B03 Genetic dissection of arbuscular mycorrhiza development)
- Martin Parniske
Deutsche Forschungsgemeinschaft (SPP1212)
- Peter Dörmann
Deutsche Forschungsgemeinschaft (Research Training Group GRK 2064 Do520/15-1)
- Peter Dörmann
Hans Fischer Gesellschaft e. V.
- Wolfgang Eisenreich
Biotechnology and Biological Sciences Research Council
- Trevor L Wang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Keymer 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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Lipid transfer from plants to arbuscular mycorrhiza fungi
eLife 6:e29107.
https://doi.org/10.7554/eLife.29107
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