Effect of chitosan on growth and plasma membrane properties of Rhizopus stolonifer (Ehrenb.:Fr.) Vuill

The glucocorticoid drug methylprednisolone inhibits respiration in concanavalin A-stimulated rat thymocytes at concentrations that are relevant to its acute clinical efficacy against autoimmune diseases and spinal cord injury. Methylprednisolone affects several processes, including ion cycling, substrate oxidation reactions and RNA/DNA synthesis. The inhibition of respiration used to drive ATP-consuming cycles of Ca2+ and Na+ ions across the plasma membrane has been proposed to be either primary or secondary to restriction of cellular ATP supply. By comparing the effects of methylprednisolone with those of myxothiazol, an inhibitor of the mitochondrial electron transport chain, we show that the effects of methylprednisolone on Ca2+ and Na+ cycling are primary. We propose that methylprednisolone acts by affecting membrane properties to inhibit Ca2+ and Na+ uptake across the plasma membrane and to increase H+ uptake across the mitochondrial membrane, and that other effects are secondary.

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Effect of sugar starvation on plasma membrane properties of sugarbeet cell suspensions

South African Journal of Botany ◽

10.1016/s0254-6299(16)30843-2 ◽

1992 ◽

Vol 58 (4) ◽

pp. 255-257

Author(s):

E. Zamski ◽

J. van Staden ◽

J. Pearce

Keyword(s):

Plasma Membrane ◽

Cell Suspensions ◽

Membrane Properties ◽

Sugar Starvation

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Alterations in the plasma membrane properties of the myocardium of spontaneously hypertensive rats.

Hypertension ◽

10.1161/01.hyp.8.7.583 ◽

1986 ◽

Vol 8 (7) ◽

pp. 583-591 ◽

Cited By ~ 13

Author(s):

R V Sharma ◽

C A Butters ◽

R C Bhalla

Keyword(s):

Plasma Membrane ◽

Spontaneously Hypertensive Rats ◽

Membrane Properties ◽

Hypertensive Rats ◽

Spontaneously Hypertensive

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Exploration of Lipid Metabolism in Relation with Plasma Membrane Properties of Duchenne Muscular Dystrophy Cells: Influence of L-Carnitine

PLoS ONE ◽

10.1371/journal.pone.0049346 ◽

2012 ◽

Vol 7 (11) ◽

pp. e49346 ◽

Cited By ~ 21

Author(s):

Françoise Le Borgne ◽

Stéphane Guyot ◽

Morgan Logerot ◽

Laurent Beney ◽

Patrick Gervais ◽

...

Keyword(s):

Plasma Membrane ◽

Lipid Metabolism ◽

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Membrane Properties

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Alkyl gallates display elicitor activities in tobacco plants

10.1101/145425 ◽

2017 ◽

Author(s):

Pascale Goupil ◽

Razik Benouaret ◽

Claire Richard

Keyword(s):

Cell Death ◽

Plasma Membrane ◽

Target Genes ◽

Crop Protection ◽

Membrane Properties ◽

List Type ◽

Ethyl Gallate ◽

Tobacco Plants ◽

Tobacco Leaves ◽

Alkyl Gallates

AbstractAlkyl gallates showed elicitor activities on tobacco in both whole plants and cell suspensions. Methyl gallate (MG), ethyl gallate (EG) and n-propyl gallate (PG) infiltration into tobacco leaves induced hypersensitive reaction-like lesions and topical production of autofluorescent compounds revealed under UV light. When sprayed on tobacco plants at 5 mM, EG promoted upregulation of defence-related genes such as the antimicrobial PR1, β-1,3-glucanase PR2, chitinase PR3 and osmotin PR5 target genes. Tobacco BY-2 cells challenged with EG underwent cell death in 48 h, significantly reduced in the presence of the protease inhibitor aprotinin. The three alkyl gallates all caused alkalinisation of the BY-2 extracellular medium, whereas gallic acid did not trigger any pH variation. Using EGTA or LaCl3, we showed that Ca2+ mobilisation occurred in BY-2 cells elicited with EG. Overall, our findings are the first evidence of alkyl gallate elicitor properties with early perception events on plasma membrane, potential hypersensitive reactions and PR-related downstream defence responses in tobacco.Highlights–Alkyl gallates elicited defence reactions in tobacco–Alkyl gallates induced local biochemical changes in tobacco leaves–Alkyl gallates caused modification of plasma membrane properties–Ethyl gallate led to defence transcript accumulation and dose-dependent cell death associated with hypersensitive response–Alkyl gallates are novel elicitor agents well-suited to crop protection schemes.

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Effects of Proteus mirabilis Lipopolysaccharides with Different O-Polysaccharide Structures on the Plasma Membrane of Human Erythrocytes

Zeitschrift für Naturforschung C ◽

10.1515/znc-2008-5-624 ◽

2008 ◽

Vol 63 (5-6) ◽

pp. 460-468 ◽

Cited By ~ 4

Author(s):

Michał Arabski ◽

Krzysztof Gwoździński ◽

Beata Sudak ◽

Wiesław Kaca

Keyword(s):

Plasma Membrane ◽

Membrane Proteins ◽

Erythrocyte Membrane ◽

Osmotic Fragility ◽

Membrane Lipid ◽

Membrane Properties ◽

Physical Parameters ◽

Chemical Structures ◽

Lipid Fluidity ◽

Membrane Lipid Fluidity

The effects of O33 and O49 P. mirabilis lipopolysaccharides (LPSs) on human erythrocyte membrane properties were examined. Physical parameters of the plasma membrane, such as membrane lipid fluidity, physical state of membrane proteins, and osmotic fragility, were determined. The fluidity of the lipids was estimated using three spin-labeled stearic acids of doxyl derivatives: 5-doxylstearic acid, 12-doxylstearic acid, and 16-doxylstearic acid. All the applied labels locate to different depths of the lipid layer and provide information on the ordering of phospholipid fatty acyl chain mobility. LPSs O49 increased the membrane lipid fluidity in the polar region of the lipid bilayer as indicated by spin-labeled 5-doxylstearic acid. An increase in fluidity was also observed in the deeper region using 12-doxylstearic acid only for O33 LPSs. The highest concentration of O33 LPSs (1 mg/ml) increased the motion of membrane proteins detected by the spin-label residue of iodoacetamide. These results showed different actions of O33 and O49 LPSs on the plasma membrane due to the different chemical structures of O-polysaccharides. P. mirabilis O33 and O49 LPSs did not induce changes in the membrane cytoskeleton, osmotic fragility and lipid peroxidation of erythrocytes. On the other hand a rise in the content of carbonyl compounds was observed for the highest concentrations of O33 LPS. This result indicated protein oxidation in the erythrocyte membrane. Lipid A, the hydrophobic part of LPS, did not change the membrane lipid fluidity and osmotic fragility of erythrocytes. Smooth and rough forms of P. mirabilis LPSs were tested for their abilities for complement-mediated immunohemolysis of erythrocytes. Only one out of seven LPSs used was a potent agent of complement-mediated hemolysis. It was rough, Ra-type of P. mirabilis R110 LPS. The O-polysaccharide-dependent scheme of reaction is presented.

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Proton conductance of the plasma membrane: properties, regulation, and functional role

AJP Cell Physiology ◽

10.1152/ajpcell.1993.265.1.c3 ◽

1993 ◽

Vol 265 (1) ◽

pp. C3-C14 ◽

Cited By ~ 109

Author(s):

G. L. Lukacs ◽

A. Kapus ◽

A. Nanda ◽

R. Romanek ◽

S. Grinstein

Keyword(s):

Plasma Membrane ◽

Plasma Membranes ◽

Second Messengers ◽

Cell Types ◽

Membrane Properties ◽

Transport Systems ◽

Extracellular Acidification ◽

Phagocyte Nadph Oxidase ◽

Selective Permeability ◽

Conductive Pathway

H+ conductive pathways have been detected in the plasma membranes of a variety of cell types. The large exquisitely H(+)-selective permeability of the conductive pathway can support sizable net H+ fluxes. Although subtle differences exist among tissues and species, certain common features suggest that related transport systems are involved in all cases. The H+ conductance is gated by depolarizing voltages and is promoted by intracellular acidification. Conversely, extracellular acidification inhibits the conductance. These features facilitate net H+ efflux, while precluding potentially deleterious H+ uptake. In some cell types, activation of the conductance is additionally controlled by physiological ligands and by second messengers. The conductance most likely functions in the regulation of intracellular pH, contributing to the extrusion of H+ during repetitive depolarization of the plasma membrane, as occurs in neurons and muscle cells. This pathway may be particularly relevant in the case of phagocytes. When stimulated, these cells undergo a sustained depolarization, while generating large amounts of metabolic acid. In addition, conductive H+ fluxes may also provide counterions to neutralize the activity of electrogenic enzymes, as suggested for the phagocyte NADPH oxidase.

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Arabidopsis annexin 5 controls plasma membrane properties in mature pollen grains

10.1101/2021.03.02.433530 ◽

2021 ◽

Author(s):

Małgorzata Lichocka ◽

Magdalena Krzymowska ◽

Magdalena Górecka ◽

Jacek Hennig

Keyword(s):

Plasma Membrane ◽

Controlled Release ◽

Membrane Integrity ◽

Pollen Grains ◽

Deionized Water ◽

Membrane Properties ◽

Water Influx ◽

Stigma Surface

AbstractIn Arabidopsis, a dry stigma surface enables a gradual hydration of pollen grains by a controlled release of water. Occasionally the grains may be exposed to extreme precipitations that cause rapid water influx, swelling and eventually lead to pollen membrane (PM) rupture. In metazoans, calcium- and phospholipids-binding proteins, referred to as annexins participate in repair of the plasma membrane damages. It remains unclear, however, how this process is conducted in plants. Here, we examined whether the plant annexin 5 (ANN5), the most abundant member of the annexin family in pollen, is involved in the restoration of PM integrity. We analyzed a cellular dynamics of ANN5 in the pollen grains undergoing in vitro and in vivo hydration. We observed a transient ANN5 association to PM during the in vitro hydration that did not occur in the pollen grains being hydrated on the stigma. To simulate a rainfall, we performed spraying of the pollinated stigma with deionized water that induced ANN5 accumulation at PM. Similarly, calcium or magnesium application affected PM properties and induced ANN5 recruitment to PM. Our data suggest a model, in which ANN5 is involved in the maintenance of membrane integrity in pollen grains exposed to osmotic or ionic imbalances.

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