Search results for "Plants"
showing 10 items of 1914 documents
Synthetic cartography for mapping biodiversity in the Mediterranean region: Sicily as a case study
2018
This paper proposes a new hierarchical land classification system for the mapping of species distribution at national or regional scales. Our integrative framework incorporates two hierarchical levels inferred from historical, climatic, geomorphological and geological attributes. The feasibility of this proposal is based on the use of historical collections and literature data, as well as on its ability to combine old low-precision data with more recent records of higher resolution. The system is set up for vascular plants, but it can also be used for other taxonomic groups. Furthermore, it has the potential for application to the whole Mediterranean region because it is based on informatio…
Regulation of plant NADPH oxidase.
2007
Addendum to: Regulation of Reactive Oxygen Species Production by a 14-3-3 Protein in Elicited Tobacco Cells. T. Elmayan, J. Fromentin, C. Riondet, G. Alcaraz, J. Blein and F. Simon-Plas. Plant Cell Environ 2007; 30:722–32; International audience; The production of Reactive Oxygen Species (ROS) is one of the key events occurring during the response of plants to environmental changes, and contributing to establish adaptive signaling pathways. A plasma membrane bound NADPH oxidase enzyme has been evidenced as the ROS producing system in various plant‑microorganisms interactions. We very recently reported, that a protein of the 14‑3‑3 family was able to interact directly with the C‑terminus par…
Molecular Bases for Sensitivity to Tubulin-Binding Herbicides in Green Foxtail
2004
Abstract We investigated the molecular bases for resistance to several classes of herbicides that bind tubulins in green foxtail (Setaria viridis L. Beauv.). We identified two α- and two β-tubulin genes in green foxtail. Sequence comparison between resistant and sensitive plants revealed two mutations, a leucine-to-phenylalanine change at position 136 and a threonine-to-isoleucine change at position 239, in the gene encoding α2-tubulin. Association of mutation at position 239 with herbicide resistance was demonstrated using near-isogenic lines derived from interspecific pairings between green foxtail and foxtail millet (Setaria italica L. Beauv.), and herbicide sensitivity bioassays combine…
Evidence for a geranyl-diphosphate synthase located within the plastids of Vitis vinifera L. cultivated in vitro
1992
Intact plastids from cell suspensions of Vitis vinifera L. cv. Muscat de Frontignan, free of detectable contamination by other particles as judged by the distribution of organelle-specific marker enzymes and by electron microscopy, exhibit geranyl-diphosphate synthase activity (EC 2.5.1.1). This synthase activity remains stable after tryptic digestion of unlysed organelles and is enhanced by plastid disruption. We conclude that the enzyme is located within the organelle. The possibility of an isopentenyl diphosphate/dimethylallyl diphosphate translocating system which would play a major role in the regulation of monoterpene metabolism is discussed.
Evidence for specific, high-affinity binding sites for a proteinaceous elicitor in tobacco plasma membrane
1995
Abstract Binding of cryptogein, a proteinaceous elicitor, was studied on tobacco plasma membrane. The binding of the [125I]cryptogein was saturable, reversible and specific with an apparent Kd of 2 nM. A single class of cryptogein binding sites was found with a sharp optimum pH for binding at about pH 7.0. The high-affinity correlates with cryptogein concentrations required for biological activity in vivo.
Comparison of the effects of cryptogein and oligogalacturonides on tabacco cells and evidence of different forms of desensitization induced by these …
1998
Abstract The effects of cryptogein and oligogalacturonides (OGs) were compared on tobacco cells by measuring calcium influx and calcium-dependent responses including extracellular alkalinization and H 2 O 2 production. The main difference is the higher calcium influx and the sustained H 2 O 2 production induced by cryptogein compared to OGs. Amplitude and duration of calcium signalling triggered by cryptogein or OGs may explain the necrotic effect of cryptogein, and the absence of necrosis in tobacco plants treated with OGs. We used induction of alkalinization and H 2 O 2 production to investigate cryptogein effects after a first treatment with cryptogein or OGs, and reciprocally. Results s…
No apparent effect of invasive alien goldenrod on soil microbial communities or soil fauna feeding activity
2020
Abstract Invasive alien species spreading in abandoned agricultural landscape may negatively affect native organisms, including plants and soil biota. This study assessed the effects of invasion by Solidago sp. (goldenrod) in southern Poland on soil fauna feeding activity and on soil microorganism activity, biomass, and functional and taxonomic diversity, in a comparisons of paired plots: goldenrod-invaded plots and nearby non-invaded plots of semi-natural grassland. Goldenrod-invaded plots had fewer vascular plant species (paired t-test) than non-invaded ones, and showed a distinct plant community composition (ANOSIM). Non-invaded and invaded plots did not differ in a range of measured soi…
Characterization of a proton pump from Acer pseudoplatanus cell microsomes
1985
Abstract An Acer pseudoplatanus cell microsomal fraction was enriched in ATPase by sedimentation through a sucrose cushion and treatment with Triton X-100. This activity, which reached 0.9 μmol P i min −1 mg −1 protein, was specific for ATP, slightly stimulated by K + , inhibited by orthovanadate and diethylstilbestrol, insensitive to oligomycin and azide, and had a K m - value of 0.51 mM for MgATP. ATP-dependent proton translocation was demonstrated by the ΔpH probe acridine orange. This activity had a optimum at pH 6.5, was substrate specific for ATP, and was strongly dependent on K + . Preparations of plasma membrane ATPase from A. pseudoplatanus cell culture thus posses biochemical prop…
Kinetic studies on protoporphyrinogen oxidase inhibition by diphenyl ether herbicides
1991
Diphenyl ethers (DPEs) and related herbicides are powerful inhibitors of protoporphyrinogen oxidase, an enzyme involved in the biosynthesis of haems and chlorophylls. The inhibition kinetics of protoporphyrinogen oxidase of various origins by four DPEs, (methyl)-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid (acifluorfen and its methyl ester, acifluorfen-methyl), methyl-5-[2-chloro-4-(trifluoromethyl) phenoxy]-2-chlorobenzoate (LS 820340) and methyl-5-[2-chloro-5-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid (RH 5348), were studied. The inhibitions of the enzymes from maize (Zea mays) mitochondrial and etiochloroplastic membranes and mouse liver mitochondrial membranes were com…
Characterization of (3H) acifluorfen binding to purified pea etioplasts, and evidence that protoporphyrinogen oxidase specifically binds acifluorfen
1992
It is now generally accepted that protoporphyrinogen oxidase is the target-enzyme for diphenylether-type herbicides. Recent studies [Camadro, J-M., Matringe, M., Scalla, R. & Labbe, P. (1991) Biochem. J. 277, 17–21] have revealed that in maize, diphenyl ethers competitively inhibit protoporphyrinogen oxidase with respect to its substrate, protoporphyrinogen IX. In this study, we show that, in purified pea etioplast, [3H]acifluorfen specifically binds to a single class of high-affinity binding sites with an apparent dissociation constant of 6.2 ± 1.3 nM and a maximum density of 29 ± 5 nmol/g protein. [3H]Acifluorfen binding reaches equilibrium in about 1 min at 30°C. Half dissociation occurs…