Regulation of photosynthetic electron flow on dark to light transition by Ferredoxin:NADP(H) Oxidoreductase interactions
- Queen Mary University of London, United Kingdom
- University of Münster, Germany
- University of Osnabrueck, Germany
- CNRS, France
- CEA-Grenoble, France
Abstract
During photosynthesis, electron transport is necessary for carbon assimilation and must be regulated to minimize free radical damage. There is a longstanding controversy over the role of a critical enzyme in this process (ferredoxin:NADP(H) oxidoreductase, or FNR), and in particular its location within chloroplasts. Here we use immunogold labelling to prove that FNR previously assigned as soluble is in fact membrane associated. We combined this technique with a genetic approach in the model plant Arabidopsis, to show that the distribution of this enzyme between different membrane regions depends on its interaction with specific tether proteins. We further demonstrate a correlation between the interaction of FNR with different proteins and the activity of alternative photosynthetic electron transport pathways. This supports a role for FNR location in regulating photosynthetic electron flow during the transition from dark to light.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files, except individual electron micrographs. Micrographs of chloroplasts that were analysed have been deposited at Dryad (https://doi.org/10.5061/dryad.7d7wm37rs) for full transparency. These are marked, to indicate the areas of the chloroplast analysed.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (SFB944 project 2)
- Guy Thomas Hanke
Biotechnology and Biological Sciences Research Council (BB/R004838/1)
- Guy Thomas Hanke
University Grenoble Alpes graduate school (ANR-10-LABX-49-01)
- Giovanni Finazzi
European Research Council (ERC Chloro-mito (833184)
- Giovanni Finazzi
LabEx Saclay Plant Sciences-SPS (ANR-10-LABX-0040-SPS)
- Anja Krieger-Liszkay
French Infrastructure for Integrated Structural Biology (ANR-10-INSB-05)
- Anja Krieger-Liszkay
Bayer CropScience (F-2016-BS-0555)
- Manuela Kramer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Kramer 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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Regulation of photosynthetic electron flow on dark to light transition by Ferredoxin:NADP(H) Oxidoreductase interactions
eLife 10:e56088.
https://doi.org/10.7554/eLife.56088
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