Objective
50-70% of the world biological nitrogen fixation, leading to a terrestrial input of 40-50 million tons of nitrogen per year, is carried out by symbiotic nitrogen fixation (SNF), mostly between bacteria of the family Rhizobiaceae and legume plants. A specif ic molecular dialogue takes place during the early steps of the symbiosis, leading to the production of key signalling lipooligosaccharides (Nod factors) by the bacterial partner. Nod factors are essential for the production of specific organs in which SNF takes place, the root nodules, and for Rhizobium infection via infection threads, which form in root hairs and then grow into root and nodule tissues. Profiling the transcriptome of the two model legumes Medicago truncatula and Lotus japonicus led to iden tification of remorin genes that are specifically expressed during symbiotic interactions. In M. truncatula the expression of this gene is induced already 48 hours after Nod factor treatment (A. Niebel, H. Kuster, P. Gamas; non published data); and this up -regulation is even more striking in developing and mature nodules (more than a thousand fold as determined by real-time PCR). Remorins represent a plant specific protein family with similarities to a 30 kD viral movement protein that is involved in macrom olecular trafficking through plasmodesmata. Their recent discovery in lipid rafts together with their structure suggest a potential role in cell to cell communication. Interestingly it was recently shown that remorins are most abundant in meristematic tiss ues and in phloem, which is consistent with a role in development. The aim of the project is to understand the role of remorin during the symbiotic Sinorhizobium meliloti-M. truncatula interaction by: a. Detailed expression analysis b. Generation and analy sis of transgenic roots/plants over-expressing or silencing the remorin gene c. Protein localisation and analysis of lipid raft mediated signalling d. Identification of interacting partners
Fields of science
- natural sciencesbiological sciencesmicrobiologybacteriology
- natural sciencesbiological sciencesbiochemistrybiomoleculesproteins
- natural sciencesphysical sciencesopticsmicroscopyelectron microscopy
- natural sciencesphysical sciencesopticsmicroscopyfluorescence lifetime imaging
- natural sciencesbiological sciencesbiochemistrybiomoleculeslipids
Keywords
Call for proposal
FP6-2004-MOBILITY-5
See other projects for this call
Funding Scheme
EIF - Marie Curie actions-Intra-European FellowshipsCoordinator
CASTANET TOLOSAN
France