Search results for "oligo"

Are the xyloglucans new elicitors of plant immunity ?

2017

Damaged-Associated Molecular Patterns (DAMPs) are endogenous molecules released from the plant cell wall after wounding by pathogens. DAMPs are recognized by Pattern- Recognition Receptors (PRRs) that play a key role in plant immunity by mediating defense responses. The plant cell wall-derived oligogalacturonides (OG) are well characterized DAMPs that elicit plant immune responses such as MAPK activation, [Ca2+]cyt variations, H2O2 production, defense-related gene expression and enhanced resistance against Botrytis cinerea. Our study focused on a new polysaccharide component of the plant cell wall called xyloglucans (Xh) and compared the immune events triggered by OG and Xh in Arabidopsis t…

Ecophysiological analysis of the nitrophily of weed species

2013

International audience

Characterization and role of nitric oxide production in Arabidopsis thaliana defense responses induced by oligogalacturonides

2011

Nitric oxide (NO) regulates a wide range of plant processes from development toenvironmental adaptation. In this study, NO production and its effects were investigated in aplant-pathogen context. The production of NO following Arabidopsis treatment witholigogalacturonides (OGs), an endogenous elicitor of plant defense, was assessed using the NOsensitive probe 4, 5-diamino fluorescein diacetate. Pharmacological and genetic approaches wereused to analyze NO enzymatic sources and its role in the Arabidopsis thaliana /Botrytis cinereainteraction. We showed that NO production involves both a L-arginine- and a nitrate reductase(NR)-pathways. OGs-induced NO production was Ca2+-dependent and modula…

Microglia and α-synuclein implication in Parkinson's disease

2011

Age-related neurodegenerative disorders like Parkinson’s disease take an enormous toll on individuals and on society. Despite extensive efforts, Parkinson’s disease remains incurable and only very limited treatments exist. Indeed, Parkinson’s pathogenesis is still not clear and research on its molecular mechanisms is ongoing. In this study, we focused our interest on two abnormal events occurring in Parkinson’s patients, namely α-synuclein aggregation and microglial activation. We first investigated α-synuclein and its abnormal polymerisation. For this purpose, we developed novel methods, which allowed the in vitro production of different types of α-synuclein oligomers. Using highly sensiti…

Calcium signaling in plant defense: involvement of subcellular compartments and glutamate receptorsCalcium signaling in plant defense: involvement of…

2012

Microbial ecology of the rhizosphere

2006

Part II. Selected MethodsPlant-microbe Chapitre 9 : Interactions and Soil Quality; International audience

Etude du système de perception des chito--oligosaccharides chez la vigne et rôle dans l'immunité.

2014

Rapport de stage Master II R SPE IPM; Master

Recherche de récepteurs de l’immunité des plantes et étude de l’impact de biostimulants sur leur expression et la résistance induite chez des organes…

2021

National audience; La stimulation des défenses immunitaires des plantes représente une stratégie durable deprotection des cultures qui pourrait permettre de réduire l’utilisation de pesticides chimiquesencore trop répandue en viticulture. Son principe réside en l’application, au contact des cellulesvégétales, de molécules élicitrices détectées comme des signaux de danger par la plante. Cessignaux de dangers peuvent être de différente nature et origine comme par exemple la chitine,un chito-oligosaccharide (COS) retrouvé dans les parois fongiques. Leur détection par desrécepteurs de l’immunité entraine une cascade de signalisation complexe, conduisant àl’activation de réactions de défense et …

Immobilization of single-stranded DNA fragments to solid surfaces and their repeatable specific hybridization : covalent binding or adsorption ?

2004

Abstract The different steps of the immobilization process of single-stranded DNA (ssDNA) on surfaces by means of chemical grafting have been investigated using systematic measurements of grafting and hybridization densities by means of radioactive labelling. The immobilization by chemical grafting to a dense monomolecular layer of N-hydroxysuccinimidyl ester reactive functions attached to silica plates was performed from a dilute solution of amino-terminated oligonucleotides (10 μmol/l). The slow evaporation of the solvent allowed to increase the DNA grafting density by a factor of 10. A precise control of the rinsing process that followed the immobilization reaction allowed the discrimina…

Biochemical and structural features of a novel cyclodextrinase from cow rumen metagenome.

2007

A novel enzyme, RA.04, belonging to the alpha-amylase family was obtained after expression of metagenomic DNA from rumen fluid (Ferrer et al.: Environ. Microbiol. 2005, 7, 1996-2010). The purified RA.04 has a tetrameric structure (280 kDa) and exhibited maximum activity (5000 U/mg protein) at 70 degrees C and was active within an unusually broad pH range from 5.5 to 9.0. It maintained 80% activity at pH 5.0 and 9.5 and 75 degrees C. The enzyme hydrolyzed alpha-D-(1,4) bonds 13-fold faster than alpha-D-(1,6) bonds to yield maltose and glucose as the main products, and it exhibited transglycosylation activity. Its preferred substrates, in the descending order, were maltooligosaccharides (C3-C…