Integration of nutrient signaling pathways
Group leader: Alain Gojon
Research Director INRAE
nitrogen nutrition, transport and sensing of nitrate, N and C signaling, root development, climate change
Our group investigates the mechanisms governing the uptake of nitrate by plant roots.
Nitrate (NO3–) is the main nitrogen (N) source for the nutrition of most plant species. Its uptake by the roots is the first step of the inorganic nitrogen assimilation process, which is, as photosynthesis, a fundamental function at the basis of plant autotrophy. Moreover, it constitutes a key factor of crop productivity that now must take into account the urgent needs for lower nitrogen fertilizer input and adaptation to global climate change. These considerations are at the heart of the development of sustainable and environmentally-friendly agriculture.
Our work focuses on two main components controlling root nitrate acquisition: the membrane transport systems for nitrate and the root system architecture. The main aim is to identify molecular mechanisms allowing the plants to modulate root nitrate uptake in response to changes in external nitrate availability or in their own nutritional status (N starvation or satiety, fluctuations of photosynthesis, CO2 elevation).
We mostly study, in Arabidopsis thaliana, mechanisms involved in the sensing of nitrate, in the regulation of nitrate transport systems, and in the control of root development.
Our approach is integrative as it aims to understand (i) how one specific signaling pathway allows the coordination between physiological and developmental responses (nitrate transport and root development, respectively), (ii) how various regulatory mechanisms acting at separate levels (transcription factors, chromatin dynamics, protein expression and trafficking, protein/protein interactions, posttranslational modifications) contribute to the same functional response, and (ii) how different signaling pathways interact to trigger an integrated response of the roots to separate signals (e.g., nitrogen and carbon signals).
We use molecular physiology, functional genomics and systems biology approaches: transcriptomics, gene networks modeling, proteomics, reverse genetics, functional phenotyping, root architecture analysis, imaging, isotope labeling.
- For more than 15 years, our group has been at the forefront of the functional characterization of membrane nitrate transporters (e.g., NRT2.1), and of the identification of their regulatory mechanisms (regulation by nitrate, by whole plant N status, and by photosynthesis).
See: Lejay et al. 1999, Cerezo et al. 2001, Lejay et al. 2003, Wirth et al. 2007, Lejay et al. 2008, Widiez et al. 2011, Laugier et al. 2012, de Jong et al. 2014, Alvarez et al. 2014.
- We have unravelled a novel mechanism of nitrate sensing involving the dual transport/sensing function of the nitrate transporter (transceptor) NRT1.1/NPF6.3. NRT1.1/NPF6.3 triggers many different responses of the plant to nitrate, including regulation of other nitrate transporters and regulation of lateral root growth.
See: Muños et al. 2004, Remans et al. 2006, Krouk et al. 2010, Gojon et al. 2011, Bouguyon et al. 2015, Bouguyon et al. 2016.
See also : prize of the French Academy of sciences: Nitrogen nutrition in plants: root growth guided by protein, and press releases: Les stratégies des plantes pour optimiser l’utilisation des nitrates (in French), Détection des ions minéraux par les plantes : du nouveau pour le nitrate et le phosphate (in French).
- Our group has organized the EMBO Conference Nitrogen2016 (Third International Symposium on the Nitrogen Nutrition of Plants, August 2016, Montpellier, France), and has edited a special issue of the Journal of Experimental Botany associated with this conference (Special Issue: Nitrogen Nutrition in Plants: Rapid Progress and New Challenges).
Bellegarde F, Gojon A, Martin A (2017) Signals and players in the transcriptional regulation of root responses by local and systemic N signaling in Arabidopsis thaliana. J. Exp. Bot., 68(10):2553-2565
Jacquot A, Li Z, Gojon A, Schulze W, Lejay L (2017) Post-translational regulation of nitrogen transporters in plants and microorganisms. J. Exp. Bot., 68(10):2567-2580
Bouguyon E, Perrine-Walker F, Pervent M, Rochette J, Cuesta C, Benková E, Martinière A, Bach L, Krouk G, Gojon A, Nacry P (2016) Nitrate controls root development through post-transcriptional regulation of the NRT1.1/NPF6.3 transporter/sensor. Plant Physiol., 172(2):1237-1248
O’Brien JA, Vega A, Bouguyon E, Krouk G, Gojon A, Coruzzi GM, Gutiérrez RA (2016) Nitrate transport, sensing and responses in plants. Mol. Plant, 9(6):837-856
Bouguyon E, Brun F, Meynard D, Kubeš M, Pervent M, Léran S, Lacombe B, Krouk G, Guiderdoni E, Zažímalová E, Hoyerová K, Nacry P, Gojon A (2015) Multiple mechanisms of nitrate sensing by Arabidopsis nitrate transceptor NRT1.1. Nat. Plants, 1:15015
Alvarez JM, Riveras E, Vidal EA, Gras DE, Contreras-López O, Tamayo KP, Aceituno F, Gómez I, Ruffel S, Lejay L, Jordana X, Gutiérrez RA (2014) Systems approach identifies TGA1 and TGA4 transcription factors as important regulatory components of the nitrate response of Arabidopsis thaliana roots. Plant J., 80(1):1-13
de Jong F, Thodey K, Lejay L, Bevan MW (2014) Glucose elevates NITRATE TRANSPORTER2.1 protein levels and nitrate transport activity independently of its HEXOKINASE1-mediated stimulation of NITRATE TRANSPORTER2.1 expression. Plant Physiol., 164(1):308-320
Ruffel S, Gojon A, Lejay L (2014) Signal interactions in the regulation of root nitrate uptake. J. Exp. Bot., 65(19):5509-5517
Nacry P, Bouguyon E, Gojon A (2013) Nitrogen acquisition by roots: physiological and developmental mechanisms ensuring plant adaptation to a fluctuating resource. Plant Soil, 370(1-2):1-29
Laugier E, Bouguyon E, Mauriès A, Tillard P, Gojon A, Lejay L (2012) Regulation of high-affinity nitrate uptake in roots of Arabidopsis depends predominantly on post-transcriptional control of the NRT2.1/NAR2.1 transport system . Plant Physiol., 158(2):1067-1078
Gojon A, Krouk G, Perrine-Walker F, Laugier E (2011) Nitrate transceptor(s) in plants. J. Exp. Bot., 62(7):2299-2308
Widiez T*, El Kafafi ES*, Girin T, Berr A, Ruffel S, Krouk G, Vayssières A, Shen WH, Coruzzi GM, Gojon A, Lepetit M (2011) HIGH NITROGEN INSENSITIVE 9 (HNI9)-mediated systemic repression of root NO3– uptake is associated with changes in histone methylation. P. Natl. Acad. Sci. USA, 108(32):13329-13334
Krouk G, Lacombe B, Bielach A, Perrine-Walker F, Malinska K, Mounier E, Hoyerová K, Tillard P, Leon S, Ljung K, Zažímalová E, Benková E, Nacry P, Gojon A (2010) Nitrate-regulated auxin transport by NRT1.1 defines a mechanism for nutrient sensing in plants. Dev. Cell, 18(6):927-937
Gojon A, Nacry P, Davidian J-C (2009) Root uptake regulation: a central process for NPS homeostasis in plants. Curr. Opin. Plant Biol., 12(3):328-338
Krouk G, Tranchina D, Lejay L, Cruikshank AA, Shasha DE, Coruzzi GM, Gutiérez RA (2009) A systems approach uncovers restrictions for signal interactions regulating genome-wide responses to nutritional cues in Arabidopsis. PloS Comput. Biol., 5:e1000326
Lejay L*, Wirth J*, Pervent M, Cross J M-F, Tillard P, Gojon A (2008) Oxidative Pentose Phosphate Pathway-dependent sugar sensing as a mechanism for regulation of root ion transporters by photosynthesis. Plant Physiol., 146(4):2036-2053
Wirth J*, Chopin F*, Santoni V, Viennois G, Tillard P, Krapp A, Lejay L, Daniel-Vedele F, Gojon A (2007) Regulation of root nitrate uptake at the NRT2.1 protein level in Arabidopsis thaliana. J. Biol. Chem., 282(32):23541-23552
Remans T, Nacry P, Pervent M, Filleur S, Diatloff E, Mounier E, Tillard P, Forde BG, Gojon A (2006) The Arabidopsis NRT1.1 transporter participates in the signaling pathway triggering root colonization of nitrate-rich patches. P. Natl. Acad. Sci. USA, 103(50):19206-19211
Muños S, Cazettes C, Fizames C, Gaymard F, Tillard P, Lepetit M, Lejay L, Gojon A (2004) Transcript profiling in the chl1-5 mutant of Arabidopsis reveals a role of the nitrate transporter NRT1.1 in the regulation of another nitrate transporter, NRT2.1. Plant Cell, 16:2433-2447
Lejay L, Gansel X, Cerezo M, Tillard P, Müller C, Krapp A, von Wirén N, Daniel-Vedele F, Gojon A (2003) Regulation of root ion transporters by photosynthesis: functional importance and relation with hexokinase. Plant Cell, 15:2218-2232
Cerezo M, Tillard P, Filleur S, Muños S, Daniel-Vedele F, Gojon A (2001) Major alterations of the regulation of root NO3- uptake are associated with the mutation of Nrt2.1 and Nrt2.2 genes in Arabidopsis. Plant Physiol., 127(1):262-271
Lejay L, Tillard P, Lepetit M, Olive FD, Filleur S, Daniel-Vedele F, Gojon A (1999) Molecular and functional regulation of two NO3- uptake systems by N- and C-status of Arabidopsis plants. Plant J., 18(5):509-519
- Nourollah Ahmadi / Emmanuel Guiderdoni, UMR AGAP, Cirad, Montpellier
- Anne Krapp / Christian Meyer, IJPB, INRA, Versailles
- François Roudier, UMR RDP, ENS, Lyon
- Christophe Salon, UMR Agro-écologie, INRA, Dijon
- Rodrigo Gutiérrez, Université catholique du Chili
- Waltraud Schulze, Université Hohenheim, Allemagne
- Dennis Shasha, New York University, Etats Unis
- Yi-Fang Tsay, Academia Sinica, Taiwan
- Eva Zazimalova, Czech Academy of Sciences, République Tchèque
- Projet ANR Franco-Taiwanais NITRASENSE (2017-2020)
- Projet Agropolis Fondation GENERICE (2017-2019)
- Projet INRA BAP CLIMNUTR (2017-2018)
- Projet ANR IMANA (2014-2018)
- Projet ANR blanc Franco-Allemand SIPHON (2014-2017)
- Projet INRA BAP ACCESS (2014-2015)
- Projet ANR blanc Franco-Chilien ModelN (2010-2013)
- Projet Agropolis Fondation RHIZOPOLIS (2010-2013)
Former team members
Congratulations to Valentin Chaput ( B&PMP, Integration team ) for his performance in the competition “My thesis in 180 seconds”. Qualified for the national semifinal in Paris!