Search results for "Arabidopsi"
showing 10 items of 241 documents
Regulation and role of nitric oxide production in Arabidopsis thaliana defense responses induced by oligogalacturonides
2014
SPEIPM; International audience
Defense Responses in Two Ecotypes of Lotus japonicus against Non-Pathogenic Pseudomonas syringae
2013
Lotus japonicus is a model legume broadly used to study many important processes as nitrogen fixing nodule formation and adaptation to salt stress. However, no studies on the defense responses occurring in this species against invading microorganisms have been carried out at the present. Understanding how this model plant protects itself against pathogens will certainly help to develop more tolerant cultivars in economically important Lotus species as well as in other legumes. In order to uncover the most important defense mechanisms activated upon bacterial attack, we explored in this work the main responses occurring in the phenotypically contrasting ecotypes MG-20 and Gifu B-129 of L. ja…
Interactions between Polyamines and Abiotic Stress Pathway Responses Unraveled by Transcriptome Analysis of Polyamine Overproducers
2011
Plant development and productivity are negatively regulated by adverse environmental conditions. The identification of stress-regulatory genes, networks, and signaling molecules should allow the development of novel strategies to obtain tolerant plants. Polyamines (PAs) are polycationic compounds with a recognized role in plant growth and development, as well as in abiotic and biotic stress responses. During the last years, knowledge on PA functions has been achieved using genetically modified plants with altered PA levels. In this review, we combine the information obtained from global transcriptome analyses in transgenic Arabidopsis plants with altered putrescine or spermine levels. Compa…
Identification of the cell-wall derived xyloglucan as a new damage-associated molecular pattern (DAMP) eliciting plant immunity in Vitis vinifera and…
2018
Activation of the plant immune responses requires recognition of common pathogen-associated molecular pattern (PAMP) by their cognate pattern recognition receptors (PRR). Chitin, a major component of fungal cell walls, is a well-known PAMP that triggers defense responses in several mammal and plant species.In the first part of this study, we show that two chitooligosaccharides, chitin and chitosan, act as PAMPs in grapevine (Vitis vinifera) as they elicit immune signaling events, defense gene expression, and resistance against pathogens. These two PAMPs are active in grapevine suggesting that at least one perception system exists. Phylogenetic analysis clearly distinguished three V. vinifer…
Pigment Binding, Fluorescence Properties, and Oligomerization Behavior of Lhca5, a Novel Light-harvesting Protein
2005
A new potential light-harvesting protein, named Lhca5, was recently detected in higher plants. Because of the low amount of Lhca5 in thylakoid membranes, the isolation of a native Lhca5 pigment-protein complex has not been achieved to date. Therefore, we used in vitro reconstitution to analyze whether Lhca5 binds pigments and is actually an additional light-harvesting protein. By this approach we could demonstrate that Lhca5 binds pigments in a unique stoichiometry. Analyses of pigment requirements for light-harvesting complex formation by Lhca5 revealed that chlorophyll b is the only indispensable pigment. Fluorescence measurements showed that ligated chlorophylls and carotenoids are arran…
Calcium signatures and signaling in cytosol and organelles of tobacco cells induced by plant defense elicitors
2011
Calcium signatures induced by two elicitors of plant defense reactions, namely cryptogein and oligogalacturonides, were monitored at the subcellular level, using apoaequorin-transformed Nicotiana tabacum var Xanthi cells, in which the apoaequorin calcium sensor was targeted either to cytosol, mitochondria or chloroplasts. Our study showed that both elicitors induced specific Ca2+ signatures in each compartment, with the most striking difference relying on duration. Common properties also emerged from the analysis of Ca2+ signatures: both elicitors induced a biphasic cytosolic [Ca2+] elevation together with a single mitochondrial [Ca2+] elevation concomitant with the first cytosolic [Ca2+] p…
Up-regulation of 1-deoxy-D-xylulose-5-phosphate synthase enhances production of essential oils in transgenic spike lavender.
2006
Abstract Spike lavender (Lavandula latifolia) is an aromatic shrub cultivated worldwide for the production of essential oils. The major constituents of these oils are monoterpenes, which are obtained from isopentenyl diphosphate and dimethylallyl diphosphate precursors through the plastidial methylerythritol phosphate (MEP) pathway and/or the cytosolic mevalonate pathway. 1-Deoxy-d-xylulose-5-P synthase (DXS) catalyzes the first step of the MEP pathway. A cDNA coding for the Arabidopsis (Arabidopsis thaliana) DXS was constitutively expressed in spike lavender. Gas chromatography/mass spectrometry analyses revealed that transgenic plants accumulated significantly more essential oils compared…
Deoxyxylulose 5-phosphate reductoisomerase is not a rate-determining enzyme for essential oil production in spike lavender
2014
[EN] Spike lavender (Lavandula latifolia) is an economically important aromatic plant producing essential oils, whose components (mostly monoterpenes) are mainly synthesized through the plastidial methylerythritol 4-phosphate (MEP) pathway. 1-Deoxy-d-xylulose-5-phosphate (DXP) synthase (DXS), that catalyzes the first step of the MEP pathway, plays a crucial role in monoterpene precursors biosynthesis in spike lavender. To date, however, it is not known whether the DXP reductoisomerase (DXR), that catalyzes the conversion of DXP into MEP, is also a rate-limiting enzyme for the biosynthesis of monoterpenes in spike lavender. To investigate it, we generated transgenic spike lavender plants con…
Up-regulation of an N-terminal truncated 3-hydroxy-3-methylglutaryl CoA reductase enhances production of essential oils and sterols in transgenic Lav…
2007
Spike lavender (Lavandula latifolia) essential oil is widely used in the perfume, cosmetic, flavouring and pharmaceutical industries. Thus, modifications of yield and composition of this essential oil by genetic engineering should have important scientific and commercial applications. We generated transgenic spike lavender plants expressing the Arabidopsis thaliana HMG1 cDNA, encoding the catalytic domain of 3-hydroxy-3-methylglutaryl CoA reductase (HMGR1S), a key enzyme of the mevalonic acid (MVA) pathway. Transgenic T0 plants accumulated significantly more essential oil constituents as compared to controls (up to 2.1- and 1.8-fold in leaves and flowers, respectively). Enhanced expression …
Transcriptome and metabolome analysis of citrus fruit to elucidate puffing disorder.
2014
a b s t r a c t A systems-level analysis reveals details of molecular mechanisms underlying puffing disorder in Citrus fruit. Flavedo, albedo and juice sac tissues of normal fruits and fruits displaying symptoms of puffing disorder were studied using metabolomics at three developmental stages. Microarrays were used to compare normal and puffed fruits for each of the three tissues. A protein-protein interaction network inferred from previous work on Arabidopsis identified hub proteins whose transcripts show significant changes in expression. Glycolysis, the backbone of primary metabolism, appeared to be severely affected by the disorder, based on both transcriptomic and metabolomic results. …