A guanosine tetraphosphate (ppGpp) mediated brake on photosynthesis is required for acclimation to nitrogen limitation in Arabidopsis
- Aix-Marseille University, CEA, CNRS, BIAM, France
- University of Carthage, Tunisia
- Université Paris-Saclay, UMR1318, INRAE, France
- Université Paris-Saclay, CNRS, INRAE, France
- University of Tunis El Manar, Tunisia
Abstract
Guanosine pentaphosphate and tetraphosphate (together referred to as ppGpp) are hyperphosphorylated nucleotides found in bacteria and the chloroplasts of plants and algae. In plants and algae artificial ppGpp accumulation can inhibit chloroplast gene expression, and influence photosynthesis, nutrient remobilisation, growth, and immunity. However, it is so far unknown whether ppGpp is required for abiotic stress acclimation in plants. Here, we demonstrate that ppGpp biosynthesis is necessary for acclimation to nitrogen starvation in Arabidopsis. We show that ppGpp is required for remodeling the photosynthetic electron transport chain to downregulate photosynthetic activity and for protection against oxidative stress. Furthermore, we demonstrate that ppGpp is required for coupling chloroplastic and nuclear gene expression during nitrogen starvation. Altogether, our work indicates that ppGpp is a pivotal regulator of chloroplast activity for stress acclimation in plants.
Data availability
All data presented in this study are included in the manuscript and supporting files Source Data files have been provided for Figures 1-5 (+ supplements).Sequencing data have been deposited at the European Nucleotide Archive under accession number PRJEB46181.
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Effects of ppGpp on gene expression during nitrogen deprivation in Arabidopsis.European Nucleotide Archive, PRJEB46181.
Article and author information
Author details
Funding
Agence Nationale de la Recherche (ANR-17-CE13-0005)
- Benjamin Field
Agence Nationale de la Recherche (ANR-17-EUR-0007)
- Sylvie Citerne
- Jose Caius
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Romand 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 guanosine tetraphosphate (ppGpp) mediated brake on photosynthesis is required for acclimation to nitrogen limitation in Arabidopsis
eLife 11:e75041.
https://doi.org/10.7554/eLife.75041
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