"Integration of Nutritional Functions" Team

Principal investigator: Alain Gojon Research Director INRA Tel: +33 4 99 61 29 38 Mail: gojon@supagro.inra.fr

 Presentation 

The group investigates the regulation of inorganic nitrogen uptake by the roots. Two main aspects are considered: the expression and activity of both nitrate and ammonium transport systems, and the root system architecture. We aim at identifying the molecular mechanisms allowing the plants to sense the external nitrogen availability in the soil, and to modulate root nitrogen uptake as a function of this availability and of the nutrient status of the whole plant. The regulations associated with these mechanisms play a pivotal role in the adaptive responses of the plant to various environmental stresses (nitrogen limitation, ammonium toxicity, changes in light intensity, etc…). Most of the work is on the model species Arabidopsis thaliana and Medicago truncatula. The overall approach is integrative and related to molecular physiology and functional genomics, using transcriptomics, forward and reverse genetics, functional phenotyping, developmental analyses, imaging, protein biochemistry and isotope labelling.

 Significant publications 

Krouk G, Tillard P, Gojon A (2006) Regulation of the high-affinity NO3- uptake system by NRT1.1-mediated NO3- demand signalling in Arabidopsis. Plant Physiol. 142: 1075-1086

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 signalling pathway triggering root colonisation of nitrate-rich patches. Proc. Natl. Acad. Sci. USA 103: 19206-19211

Remans T, Nacry P, Pervent M, Girin T, Tillard P, Lepetit M, Gojon A (2006) A central role for the nitrate transporter NRT2.1 in the integrated morphological and physiological responses of the root system to nitrogen limitation in Arabidopsis. Plant Physiol. 140: 909-921

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

Loqué D, Tillard P, Gojon A, Lepetit M (2003) Gene expression of the NO3- transporter NRT1.1 and the nitrate reductase NIA1 is repressed in Arabidopsis roots by NO2-, the product of NO3- reduction. Plant Physiol. 132: 958-967

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: 262-271

Gansel X, Muños S, Tillard P, Gojon A (2001) Differential regulation of the NO3- and NH4+ transporter genes AtNrt2.1 and AtAmt1.1 in Arabidopsis: Relation with long distance and local controls by N status of the plant. Plant J. 26: 143-155

More publications >>


 People 

Permanent staff
Laurence Lejay INRA - CR	Philippe Nacry INRA - CR	Benoît Lacombe CNRS - CR	Sandrine Ruffel INRA - CR	Pascal Tillard INRA - IE
Chantal Brachet INRA - TR	Cécile Fizames INRA - IE	Gabriel Krouk CNRS - CR
Graduate students and postdocs
Adeline Mauries Postdoc	Marjorie Pervent Postdoc	Eleonor Bouguyon Graduate student	Sophie Leran Graduate student	Yann Boursiac Postdoc
Anna Medici Postdoc	Jonathan Przybyla-Toscano Stagiaire M1