Nod-factor attachment, calcium-fluxes, and lipid-transfer proteins in symbiotic signal transduction

Conférence Chapitre d'actes Nod-factor attachment, calcium-fluxes, and lipid-transfer proteins in symbiotic signal transduction eng 1997 author Irving Helen R. author Boukli Hacene Tani Nawal Maria 98513 author Toomre D. author Krause Andréa 24341 author Gehring C.A. author Jabbouri Said 29315 author Kabbara A.A. author Seidel Kerstin 107253 author Parish R.W. author Kader J.-C. author Varki A.A. author Broughton William John 22724 37-42 3540620567 Temporal and spatial observations on the attachment of Nodfactors were made by biotinylating the reducing terminus of the lipo-chitooligosaccharides of the broad host-range Rhizobium sp. NGR234 with the fluorescent reagent 2-amino-(6-amidobiotinyl)pyridine. Complex formation between the biotinylated Nod-factors and fluorescent streptavidin allowed localisation of the binding-site. At concentrations of > 10⁻⁷ M, these fluorescently tagged moleculs bound rapidly and asymmetrically (≈ 1 min) to nodulation competent root-hairs but they did not bind to root-hairs of the nonhost Arabidopsis thaliana. Early cellular events within the root-hairs were studied by loading root-segments with the calcium indicators Fura-2 and Fluo-3. Fluorescence ratio imaging showed that addition of NodNGR factors provoked almost immediate, plateau-like increases in intra-cellular free calcium {[Ca²⁺]i} in root-hairs and epidermal cells. Confocal laser scanning microscopy (CLSM) revealed that calcium accumulation was concentrated at the tips and the sides of the responsive root-hairs. A gene encoding a lipid transfer-like protein (LPT2) was isolated from a Vigna unguiculata root-hair cDNA bank. Levels of the L TP2-transcript increased in root-hairs 24h after treatment with NGR234, or its Nod-factors. The L TP2-gene was cloned into the pMal™ expression vector and L TP2 purified by affinity chromatography. It was unable to transfer phospholipids between liposomes and mitochondria. Anti-sense analysis in which the LTP2 coding region was cloned between the 35S promoter and terminator sequences reduced nodulation when transformed into V. unguiculata. Dewey 580 Berlin Springer NATO ASI Series : advanced science institutes series. Series G, Ecological sciences 39 45 Département des sciences végétales 163 false Biological fixation of nitrogen for ecology and sustainable agriculture: proceedings of the NATO Advanced Research Workshop "Biological Fixation of Nitrogen for Ecology and Sustainable Agriculture" Legocki, Andrzej B. September 10-14, 1996 Poznan c048b6fa-2d3a-4db3-af52-82994b15e0ce Proceedings chapter (Published version) Restricted Irving_NATO_199739037.pdf 2558821 application/pdf restrictedAccess Faculté des sciences / Section de biologie / Département des sciences végétales

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Nod-factor attachment, calcium-fluxes, and lipid-transfer proteins in symbiotic signal transduction	Biological fixation of nitrogen for ecology and sustainable agriculture: proceedings of the NATO Advanced Research Workshop "Biological Fixation of Nitrogen for Ecology and Sustainable Agriculture"			1997	421	0

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