Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros

Medicinas Complementares
Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Mol Sci ; 21(21)2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33138028

RESUMO

Rhizoctonia solani (Rs) is a soil-borne pathogen with a broad host range. This pathogen incites a wide range of disease symptoms. Knowledge regarding its infection process is fragmented, a typical feature for basidiomycetes. In this study, we aimed at identifying potential fungal effectors and their function. From a group of 11 predicted single gene effectors, a rare lipoprotein A (RsRlpA), from a strain attacking sugar beet was analyzed. The RsRlpA gene was highly induced upon early-stage infection of sugar beet seedlings, and heterologous expression in Cercospora beticola demonstrated involvement in virulence. It was also able to suppress the hypersensitive response (HR) induced by the Avr4/Cf4 complex in transgenic Nicotiana benthamiana plants and functioned as an active protease inhibitor able to suppress Reactive Oxygen Species (ROS) burst. This effector contains a double-psi beta-barrel (DPBB) fold domain, and a conserved serine at position 120 in the DPBB fold domain was found to be crucial for HR suppression. Overall, R. solani seems to be capable of inducing an initial biotrophic stage upon infection, suppressing basal immune responses, followed by a switch to necrotrophic growth. However, regulatory mechanisms between the different lifestyles are still unknown.


Assuntos
Beta vulgaris/imunologia , Lipoproteína(a)/farmacologia , Doenças das Plantas/imunologia , Proteínas de Plantas/farmacologia , Inibidores de Proteases/farmacologia , Rhizoctonia/fisiologia , Virulência , Beta vulgaris/efeitos dos fármacos , Beta vulgaris/crescimento & desenvolvimento , Beta vulgaris/microbiologia , Doenças das Plantas/microbiologia , Microbiologia do Solo
2.
Methods Mol Biol ; 1694: 141-147, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29080164

RESUMO

Diamine and polyamine catabolism controls plant development, resistance to pathogens and stress responses. Diamine and polyamine oxidases control the catabolism of diamines and polyamines, respectively. Two major routes of di-/polyamine catabolism exist: the terminal and the interconverting. The in vitro activity of each route is assayed by the colorimetric or chemiluminescent determination of hydrogen peroxide produced by oxidation of di-/polyamine substrates. However, these assays fail to estimate activity of individual di-/polyamine oxidase isoenzymes. Herein, I describe an assay for the simultaneous in-gel determination of terminal and interconverting di-/polyamine oxidase isoenzyme activities.


Assuntos
Ensaios Enzimáticos , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Plantas/enzimologia , Espermidina/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Técnicas In Vitro , Extratos Vegetais/química , Poliamina Oxidase
3.
Plant J ; 63(6): 1042-53, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20626657

RESUMO

Spermidine (Spd) has been correlated with various physiological and developmental processes in plants, including pollen tube growth. In this work, we show that Spd induces an increase in the cytosolic Ca(2+) concentration that accompanies pollen tube growth. Using the whole-cell patch clamp and outside-out single-channel patch clamp configurations, we show that exogenous Spd induces a hyperpolarization-activated Ca(2+) current: the addition of Spd cannot induce the channel open probability increase in excised outside-out patches, indicating that the effect of Spd in the induction of Ca(2+) currents is exerted via a second messenger. This messenger is hydrogen peroxide (H2O2), and is generated during Spd oxidation, a reaction mediated by polyamine oxidase (PAO). These reactive oxygen species trigger the opening of the hyperpolarization-activated Ca(2+) -permeable channels in pollen. To provide further evidence that PAO is in fact responsible for the effect of Spd on the Ca(2+) -permeable channels, two Arabidopsis mutants lacking expression of the peroxisomal-encoding AtPAO3 gene, were isolated and characterized. Pollen from these mutants was unable to induce the opening of the Ca(2+) -permeable channels in the presence of Spd, resulting in reduced pollen tube growth and seed number. However, a high Spd concentration triggers a Ca(2+) influx beyond the optimal, which has a deleterious effect. These findings strongly suggest that the Spd-derived H2O2 signals Ca(2+) influx, thereby regulating pollen tube growth.


Assuntos
Canais de Cálcio/metabolismo , Membrana Celular/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Peróxido de Hidrogênio/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Tubo Polínico/metabolismo , Pólen/metabolismo , Canais de Potássio/metabolismo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Microscopia de Fluorescência , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Técnicas de Patch-Clamp , Tubo Polínico/crescimento & desenvolvimento , Espermidina/metabolismo , Poliamina Oxidase
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA