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P. Ratet Team

Establishment of the symbiotic interaction between legume plants and Rhizobia occurs when the soil nitrogen source is limiting and leads to the de-novo formation of symbiotic nodules, generally formed on roots of the plant hosts. The symbiotic association allows the plant to overcome nitrogen limitation taking advantage of the bacterial nitrogenase activity. In return, the plant furnishes carbon derivatives to its hosts. The first steps of this symbiotic association and the formation of the symbiotic organ have been described in detail (Ferguson et al., 2010, J. Int Plant Biol., 52, 61-76; Oldroyd et al., 2011, Annu. Rev. Genet., 45, 119–144) but organ identity and later steps of the interaction related to bacterial accommodation and immunity are less understood. Rhizobia often invade the plant root using specialized symbiotic structures called infection threads. In the mature nitrogen fixing nodule, the rhizobia reside in symbiotic nodule cells within organelle-like structures, called symbiosome. In contrast to what is generally observed during microbial invasion, legumes do not elicit defense reactions during symbiosis despite that the bacterial population reaches massive densities in nodules.


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Genetic Control of the symbiosis

Grain (such as peas, faba beans, soybean, chickpea) and forage (alfalfa, clover, lupinus) legume plants are important crops worldwide for both animal and human consumption as they are major (...)

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Scientific Project

1.Characterization of symbiotic mutants affected in organ identity The NOOT1 gene is necessary for nodule identity (Couzigou et al., 2012): The Medicago truncatula noot mutant isolated in our (...)

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Team Members

Group leader : RATET Pascal
RATET Pascal (DR2, CNRS)
GARMIER Marie (MdC, Paris-Sud)
REZE Nathalie (T, CNRS)
MASSOT Sophie (T, Paris-Sud)
AIT (...)

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2017 Brusamarello-Santos LC, Gilard F, Brulé L, Quilleré I, Gourion B, Ratet P, Maltempi de Souza E, Lea PJ, Hirel B. (2017) Metabolic profiling of two maize (Zea mays L.) inbred lines inoculated (...)

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Local collaborations P. Mergaert and D. Faure (I2BC, Gif-sur-Yvette), F. Frugier (IPS2, Gif-sur-Yvette) J. Colcombet (IPS2, Gif-sur-Yvette) Abdel Bendahmane (IPS2, Gif-sur-Yvette)
National (...)

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