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Polygalacturonase-inhibiting protein accumulates in Phaseolus vulgaris L. in response to wounding, elicitors and fungal infection 总被引:7,自引:0,他引:7
Carl W. Bergmann Yuki Ito Darrell Singer Peter Albersheim Alan G. Darvill Nicole Benhamou Laurence Nuss Giovanni Salvi Felice Cervone Giulia De Lorenzo 《The Plant journal : for cell and molecular biology》1994,5(5):625-634
Polygalacturonase-inhibiting protein (PGIP) is a cell wall-associated protein that specifically binds to and inhibits the activity of fungal endopolygalacturonases. The Phaseolus vulgaris gene encoding PGIP has been cloned and characterized. Using a fragment of the cloned pgip gene as a probe in Northern blot experiments, it is demonstrated that the pgip mRNA accumulates in suspension-cultured bean cells following addition of elicitor-active oligogalacturonides or fungal glucan to the medium. Rabbit polyclonal antibodies specific for PGIP were generated against a synthetic peptide designed from the N-terminal region of PGIP; the antigenicity of the peptide was enhanced by coupling to KLH. Using the antibodies and the cloned pgip gene fragment as probes in Western and Northern blot experiments, respectively, it is shown that the levels of PGIP and its mRNA are increased in P. vulgaris hypocotyls in response to wounding or treatment with salicylic acid. Using gold-labeled goat-anti-rabbit secondary antibodies in EM studies, it has also been demonstrated that, in bean hypocotyls infected with Colletotrichum lindemuthianum, the level of PGIP preferentially increases in those cells immediately surrounding the infection site. The data support the hypothesis that synthesis of PGIP constitutes an active defense mechanism of plants that is elicited by signal molecules known to induce plant defense genes. 相似文献
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The behaviour of Pichia stipitis, Pachysolen tannophilus, Candida shehatae and Candida parapsilosis was investigated to select the most suitable yeast to convert xylose either to ethanol or to xylitol, with little or no formation of by-products. The aeration rate was used as a variable parameter. P. stipitis and C. parapsilosis were the most effective producers or ethanol and xylitol, respectively, both reaching productivities at very low levels of oxygenation. With P. stipitis, better ethanol productivity was attained under microaerobic conditions (KLa = 4·8 h−1) while with C. parapsilosis high yields and rates of xylitol production were detected at KLa values of about 16·3 h−1. P. tannophilus and C. shehatae showed lower performances under all conditions used while changes in oxygenation modified the ratio of ethanol to xylitol produced by these yeasts, suggesting that they are more dependent on the oxygen power input than P. stipitis and C. parapsilosis. The influence of oxygen transfer rates on ethanol and xylitol formation with the best producers is discussed. 相似文献
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We describe a simple and sensitive method for staining of the carbohydrate moiety of glycoproteins in polyacrylamide or agarose electrophoretic gels. Gels are incubated in a solution of fluorescein-labeled concanavalin A. Following destaining with a neutral buffer, glycoproteins exhibit fluorescence under long-range ultraviolet light. Thus, the glucose/mannose containing β- and γ-chains of human fibrinogen give fluorescent bands, whereas the carbohydrate-free α-chain does not react. Less than 100 ng of hexose bound to fibrinogen β- or γ-chains could be detected. The procedure is suitable for staining of other carbohydrate residues in glycoproteins, which can be recognised by specific agglutinins, as shown by binding of fluorescein-labeled lectins from Ricinus communis to galactose residues of fibrinogen. 相似文献
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Dr. Marino Bortolussi Giulia Marini Maria Luisa Reolon 《Cell and tissue research》1979,197(2):213-226
Summary Changes in the distribution of the in vitro uptake of 125I-HCG by the ovaries of adult rats were examined histochemically throughout the estrous cycle.Only in follicles wider than 500 m, occurring mainly at diestrus and proestrus, could granulosa cells bind the labelled hormone. The labelling increased with follicular size and decreased in intensity from the peripheral granulosa cells inwards. No uptake occurred in the oocytes, in the cells of the cumulus oophorus nor in the granulosa cells of the atretic follicles.The binding capacity of the newly-formed corpora lutea of estrus was less than that of preovulatory follicles. The uptake of 125I-HCG by corpora lutea during the first cycle reached its maximum at diestrus but fell sharply by proestrus. The uptake was patchy in the corpora lutea of the second cycle and not significant in the older ones.The uptake of 125I-HCG by thecae increased with follicular size and was greater in the thecae of atretic follicles than in the thecae of growing follicles of like size. There was a greater uptake in the last formed interstitial tissue than there was in older tissue.At proestrus, the uptake of 125I-HCG was unaffected by the LH surge at 18.00h but had decreased slightly at 24.00 h.The implications of these data in relation to the regulation of receptor sites, is discussed. 相似文献
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Harshad S. Ugamraj Kevin Dang Laure-Hlne Ouisse Benjamin Buelow Eduardo N. Chini Giulia Castello James Allison Starlynn C Clarke Laura M. Davison Roland Buelow Rong Deng Suhasini Iyer Ute Schellenberger Sankar N. Manika Shipra Bijpuria Astrid Musnier Anne Poupon Maria Cristina Cuturi Wim van Schooten Pranjali Dalvi 《MABS-AUSTIN》2022,14(1)
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Human Cytomegalovirus UL131-128 Genes Are Indispensable for Virus Growth in Endothelial Cells and Virus Transfer to Leukocytes 下载免费PDF全文