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Vivienne Gianinazzipearson - One of the best experts on this subject based on the ideXlab platform.
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localization of β 1 3 glucan in walls of the Endomycorrhizal fungi glomus mosseae nicol gerd gerd trappe and acaulospora laevis gerd trappe during colonization of host roots
New Phytologist, 1995Co-Authors: M.-c. Lemoine, Armelle Gollotte, Vivienne GianinazzipearsonAbstract:summary Previous studies showed that cell walls of Endomycorrhizal fungi belonging to the Acaulosporaceae and Glomaceae contain β (1–3) glucan polymers as well as chitin. Indirect immunolabelling with monoclonal and polyclonal antibodies has been used to investigate the distribution of these structural polysaccharides in cell walls of Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe as they interact with pea and tobacco roots, respectively. The (l-3) glucans were detected in the walls of external hyphae, and of hyphal coils and intercellular hyphae developing in outer root tissues. The glucan component was alkali-insoluble but treatment with chitinase resulted in solubilization of most of the β(1–3) glucans from the fungal wall. A decrease in immunolabelling was associated with thinning out of the hyphal wall as the fungi colonized deeper in the host root, and β(1–3) glucans could not be detected in walls of intercellular hyphae or arbuscules in the parenchyma cortical tissue. The molecular configuration of cell walls of G. mosseae and A. laevis is discussed in relation to fungal morphogenesis and the symbiotic state in Endomycorrhiza.
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interactions between soil applied fungicides Endomycorrhiza fungal activity and plant growth
Soil Science (Trends in Agricultural Science), 1993Co-Authors: Jeanphilippe Guillemin, S. Gianinazzi, Alain Trouvelot, Gamalmahmoud Abdelfattah, Vivienne GianinazzipearsonAbstract:Previous reports have shown that fungicides affect Endomycorrhizas. In the present work, the effects of several soil-applied fungicides were tested on plant growth, Endomycorrhizal infection development and nutrient uptake in pot-grown soybean (cv. Amsoy 71) and micropropagated pineapple (Queen Tahiti and Smooth Cayenne varieties). Positive Endomycorrhizal effects on shoot and root growth of soybean were unaffected by application of fosetyl-Al, captan and mancozeb ; however, benomyl and quintozen significantly depressed shoot growth of Endomycorrhizal plants but significantly increased root growth. Mineral assimilation by Endomycorrhizal plants was significantly greater than in nonmycorrhizal plants except for benomyl and quintozen application. Significantly higher values of Endomycorrhizal infection were observed with trypan blue staining in fosetyl-Al and mancozeb treated plants. Benomyl and quintozen significantly reduced these values. No significant effect of any fungicide on Endomycorrhizal pineapple growth was observed except for plants treated with etridiazol. Root/shoot ratio was inversed by the fungicide applications. Mineral uptake into shoots of both pineapple varieties increased in all Endomycorrhizal plants and this positive effect was only slightly affected by fungicide application.
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occurrence and expression of acid phosphatase of hymenoscyphus ericae read korf kernan in isolation or associated with plant roots
Mycorrhiza, 1992Co-Authors: Marieclaude Lemoine, S. Gianinazzi, Vivienne Gianinazzipearson, C. J. StrakerAbstract:The activity of acid phosphatase produced in pure culture by the Endomycorrhizal fungus Hymenoscyphus ericae (Read) Korf & Kernan (H. ericae LPA 2) was inhibited by high phosphorus levels, alkaline pH, fluoride, molybdate and mannosidase, and activated by concanavalin A. Over 80% of the enzyme activity was due to two wall-bound acid phosphatase isozymes with the characteristics of mannose-rich glycoproteins. Antiserum was raised against the major, low-molecular-weight wall isozyme and its activity tested by immunoblotting and ELISA. The antiserum cross reacted 100% with exocellular (excreted) and 28% with cytoplasmic cellular fractions of H. ericae (LPA 2) cultures, and showed high reactivity with other strains of H. ericae but not with fungal isolates from Erica hispidula L. or E. mauritanica L. Ultrastructural localization of acid phosphatase by cytoenzymology and indirect immunogold labelling confirmed its association with the fungal wall in pure culture and showed that the influence of a high phosphorus level, fluoride and molybdate is through inactivation of the enzyme. Intense acid phosphatase activity, sensitive to the latter inhibitors, was also present on external hyphae growing over a host or non-host root but it was weak or absent from intracellular hyphae where these developed within a host root. Indirect immunolabelling confirmed that this acid phosphatase was of fungal origin and that the specific inhibitory effect of host cells is due to inactivation of the enzyme rather than repression of its synthesis. Possible implications of fungal acid phosphatase in ericoid Endomycorrhizal infection processes are discussed together with mechanisms that may be regulating the enzyme activity.
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cytology histochemistry and immunocytochemistry as tools for studying structure and function in Endomycorrhiza
Methods in Microbiology, 1992Co-Authors: S. Gianinazzi, Vivienne GianinazzipearsonAbstract:Publisher Summary This chapter describes some microscopical approaches for analyzing the structure of Endomycorrhizal infections, identifying modifications in protein expression (enzyme activities) and localizing specific molecules at both the tissue and cellular level. Techniques are chosen to illustrate how they can not only increase the understanding of how Endomycorrhizal symbionts interact with each other, but also furnish potential tools for diagnosing the functional state of the symbiosis. Non-destructive observations can be made of vesicular-arbuscular Endomycorrhizal infections in root pieces using ultraviolet light. Although this can be useful for selecting materials for biochemical analysis or electron microscope preparation, the technique is limited to young root tissues in which only living arbuscules can usually be detected. The chapter illustrates cytological, histochemical, and immunocytochemical techniques. It provides powerful tools for studying the structure and function of symbionts and their interactions in Endomycorrhiza. Knowledge of the physical and chemical nature of cellular and subcellular structures permitting functional compatability in Endomycorrhizal associations has been considerably improved and subcellular localization of enzyme activities has given some insight into their physiological significance for the symbiotic condition. Furthermore, by combining immunolocalization with ultra cytoenzymology it is possible to understand how the synthesis and the expression of the molecules involved are regulated.
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production of new soluble proteins during va Endomycorrhiza formation
Agriculture Ecosystems & Environment, 1990Co-Authors: E Dumas, Vivienne Gianinazzipearson, S. GianinazziAbstract:Abstract In order to investigate changes in genome expression of the symbiotic partners during Endomycorrhizal establishment, we have compared soluble protein profiles in nonmycorrhizal roots and roots infected by different VA Endomycorrhizal fungi. New proteins of fungal and host origin were detected. The relationship between host proteins and PR-b proteins, typically synthesized during host-pathogen interactions was investigated.
M.-c. Lemoine - One of the best experts on this subject based on the ideXlab platform.
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Localization of β (1–3) glucan in walls of the Endomycorrhizal fungi Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe during colonization of host roots
New Phytologist, 1995Co-Authors: M.-c. Lemoine, Armelle Gollotte, Vivienne Gianinazzi-pearsonAbstract:summary Previous studies showed that cell walls of Endomycorrhizal fungi belonging to the Acaulosporaceae and Glomaceae contain β (1–3) glucan polymers as well as chitin. Indirect immunolabelling with monoclonal and polyclonal antibodies has been used to investigate the distribution of these structural polysaccharides in cell walls of Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe as they interact with pea and tobacco roots, respectively. The (l-3) glucans were detected in the walls of external hyphae, and of hyphal coils and intercellular hyphae developing in outer root tissues. The glucan component was alkali-insoluble but treatment with chitinase resulted in solubilization of most of the β(1–3) glucans from the fungal wall. A decrease in immunolabelling was associated with thinning out of the hyphal wall as the fungi colonized deeper in the host root, and β(1–3) glucans could not be detected in walls of intercellular hyphae or arbuscules in the parenchyma cortical tissue. The molecular configuration of cell walls of G. mosseae and A. laevis is discussed in relation to fungal morphogenesis and the symbiotic state in Endomycorrhiza.
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localization of β 1 3 glucan in walls of the Endomycorrhizal fungi glomus mosseae nicol gerd gerd trappe and acaulospora laevis gerd trappe during colonization of host roots
New Phytologist, 1995Co-Authors: M.-c. Lemoine, Armelle Gollotte, Vivienne GianinazzipearsonAbstract:summary Previous studies showed that cell walls of Endomycorrhizal fungi belonging to the Acaulosporaceae and Glomaceae contain β (1–3) glucan polymers as well as chitin. Indirect immunolabelling with monoclonal and polyclonal antibodies has been used to investigate the distribution of these structural polysaccharides in cell walls of Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe as they interact with pea and tobacco roots, respectively. The (l-3) glucans were detected in the walls of external hyphae, and of hyphal coils and intercellular hyphae developing in outer root tissues. The glucan component was alkali-insoluble but treatment with chitinase resulted in solubilization of most of the β(1–3) glucans from the fungal wall. A decrease in immunolabelling was associated with thinning out of the hyphal wall as the fungi colonized deeper in the host root, and β(1–3) glucans could not be detected in walls of intercellular hyphae or arbuscules in the parenchyma cortical tissue. The molecular configuration of cell walls of G. mosseae and A. laevis is discussed in relation to fungal morphogenesis and the symbiotic state in Endomycorrhiza.
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Occurrence and expression of acid phosphatase of Hymenoscyphus ericae (Read) Korf & Kernan, in isolation or associated with plant roots
Mycorrhiza, 1992Co-Authors: M.-c. Lemoine, Vivienne Gianinazzi-pearson, S. Gianinazzi, C. J. StrakerAbstract:The activity of acid phosphatase produced in pure culture by the Endomycorrhizal fungus Hymenoscyphus ericae (Read) Korf & Kernan ( H. ericae LPA 2) was inhibited by high phosphorus levels, alkaline pH, fluoride, molybdate and mannosidase, and activated by concanavalin A. Over 80% of the enzyme activity was due to two wall-bound acid phosphatase isozymes with the characteristics of mannose-rich glycoproteins. Antiserum was raised against the major, low-molecular-weight wall isozyme and its activity tested by immunoblotting and ELISA. The antiserum cross reacted 100% with exocellular (excreted) and 28% with cytoplasmic cellular fractions of H. ericae (LPA 2) cultures, and showed high reactivity with other strains of H. ericae but not with fungal isolates from Erica hispidula L. or E. mauritanica L. Ultrastructural localization of acid phosphatase by cytoenzymology and indirect immunogold labelling confirmed its association with the fungal wall in pure culture and showed that the influence of a high phosphorus level, fluoride and molybdate is through inactivation of the enzyme. Intense acid phosphatase activity, sensitive to the latter inhibitors, was also present on external hyphae growing over a host or non-host root but it was weak or absent from intracellular hyphae where these developed within a host root. Indirect immunolabelling confirmed that this acid phosphatase was of fungal origin and that the specific inhibitory effect of host cells is due to inactivation of the enzyme rather than repression of its synthesis. Possible implications of fungal acid phosphatase in ericoid Endomycorrhizal infection processes are discussed together with mechanisms that may be regulating the enzyme activity.
S. Gianinazzi - One of the best experts on this subject based on the ideXlab platform.
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Comparison of acid soluble protein synthesis in roots of Endomycorrhizal wild type Pisum sativum and corresponding isogenic mutants
Journal of Plant Physiology, 2012Co-Authors: Luisa Schellenbaum, S. Gianinazzi, Vivienne Gianinazzi-pearsonAbstract:Summary The aim of this study was to compare profiles of acid soluble proteins in roots of Pisum sativum L. cv. Frisson and non-mycorrhizal mutants (myc − ) when infected by vesicular arbuscular mycorrhiza funghi. Quantitative and qualitative modifications were detected by native or SDS PAGE in the protein composition of acidic extracts of Endomycorrhizal roots of myc + , nod + wild type P. sativum and of a myc + , nod-mutant, as compared to uninoculated control plants or a myc − , nod − mutant, whether this was inoculated or not with Glomus mosseae . In native PAGE two proteins, already present in extracts of non-mycorrhizal pea roots, were enhanced in G. mosseae -infected myc + plants (nod + or nod − ). One protein which appeared after inoculation with G. mosseae or G. fasciculatum in the roots of all pea plants, including the myc − , nod − mutants, may be associated with appressorium formation. Four new proteins were detected in root extracts of G. mosseae -infected myc − peas (nod + or nod − ), as compared to the myc − , nod − mutant or uninoculated controls. One of these was probably of fungal origin, since it was also found in G. mosseae -infected tobacco and leek roots. These plants showed protein modifications different to those in Endomycorrhizal peas, suggesting host-specific responses. SDS PAGE revealed the presence of two polypeptides of about 25 and 35 kDa in Endomycorrhizal roots of myc + peas. None of the Endomycorrhiza-related proteins detected in roots corresponded to those extracted from spores of different fungi. This study provides new evidence that different molecular modifications occur during successful (myc + pea, leek, tobacco) and unsuccessful (myc − pea) Endomycorrhiza infections, some of which are host-determined and others related to the expression of the fungal genome.
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Techniques for the study of mycorrhiza. Vol. 2 - Cytology, Histochemistry and Immunocytochemistry as Tools for Studying Structure and Function in Endomycorrhiza
Methods in Microbiology, 2008Co-Authors: S. Gianinazzi, Vivienne Gianinazzi-pearsonAbstract:Publisher Summary This chapter describes some microscopical approaches for analyzing the structure of Endomycorrhizal infections, identifying modifications in protein expression (enzyme activities) and localizing specific molecules at both the tissue and cellular level. Techniques are chosen to illustrate how they can not only increase the understanding of how Endomycorrhizal symbionts interact with each other, but also furnish potential tools for diagnosing the functional state of the symbiosis. Non-destructive observations can be made of vesicular-arbuscular Endomycorrhizal infections in root pieces using ultraviolet light. Although this can be useful for selecting materials for biochemical analysis or electron microscope preparation, the technique is limited to young root tissues in which only living arbuscules can usually be detected. The chapter illustrates cytological, histochemical, and immunocytochemical techniques. It provides powerful tools for studying the structure and function of symbionts and their interactions in Endomycorrhiza. Knowledge of the physical and chemical nature of cellular and subcellular structures permitting functional compatability in Endomycorrhizal associations has been considerably improved and subcellular localization of enzyme activities has given some insight into their physiological significance for the symbiotic condition. Furthermore, by combining immunolocalization with ultra cytoenzymology it is possible to understand how the synthesis and the expression of the molecules involved are regulated.
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Proteins and Protein Activities in Endomycorrhizal Symbioses
Mycorrhiza, 1999Co-Authors: V. Gianinazzi-pearson, Eliane Dumas-gaudot, S. GianinazziAbstract:Very little is as yet known of the molecular processes which determine the functional integration between symbionts in Endomycorrhizal associations. The fact that, on the one hand, the obligate fungal biotrophs forming arbuscular Endomycorrhiza (AM) cannot be maintained in pure culture without the host plant and that, on the other, ericoid or orchid Endomycorrhiza have received relatively little attention, has retarded research advances in several domains, and in particular those concerning fungal identification in planta, the molecular basis of compatible interactions and determination of functional symbioses in situ. However, increasing information is being obtained using approaches that are based on the analysis of expressed genes or on metabolic activities of either symbiont in isolation or together. Proteins are key molecules in cellular metabolism and their most well known physiological function is their role as enzymes. The aim of this presentation is not to give an exhaustive review on proteins and gene expression in Endomycorrhizal symbionts (see Gianinazzi-Pearson and Smith 1993; Gianinazzi-Pearson 1996 for this), but rather to discuss what their contribution may be to symbiont compatibility, and their role as potential tools for identifying the fungal partner or the functional state of the symbiosis.
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Chitinase andβ1,3-glucanase isoforms expressed in pea roots inoculated with arbuscular mycorrhizal or pathogenic fungi
European Journal of Plant Pathology, 1996Co-Authors: B. Dassi, Eliane Dumas-gaudot, Alain Asselin, C. Richard, S. GianinazziAbstract:Chitinases were studied in an Endomycorrhiza-resistant mutant and wild type pea (Pisum sativum L. cv. Frisson) in order to characterize plant hydrolases specific to pathogenic (Aphanomyces euteiches andChalara elegans) or mycorrhizal (Glomus mosseae) root interactions. Stimulation of constitutive and induction of new chitinase activities was detected by native PAGE for acidic proteins in both pea genotypes inoculated with pathogenic fungi. In contrast, a different additional chitinase isoform was induced inG. mosseae-colonized roots. This isoform was also not elicited in chemically-stressed roots, confirming its mycorrhiza-specificity. Investigations of basic chitinase andβ-1,3-glucanase activities provided further evidence for differential pea responses during pathogenic and symbiotic interactions.
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Etude immunocytochimique des interfaces plante-champignon endomycorhizien à arbuscules chez des pois isogéniques myc+ ou résistant à l'endomycorhization (myc−)
Acta Botanica Gallica, 1994Co-Authors: Armelle Gollotte, Vivienne Gianinazzi-pearson, S. GianinazziAbstract:Summary Interactions between an arbuscular mycorrhizal fungus and pea cv. Frisson (myc+) or an isogenic mycorrhiza-resistant mutant (myc−) were investigated by immunocytochemistry. Observations of the presence of proteins and polysaccharides accumulating in other symbioses (pectins) or in plant-pathogenic interactions (PR-b1 protein, s-1,3-glucans) indicated a weak activation of defence mechanisms during establishment of symbiosis. In contrast, the myc mutant showed an important defence reaction against the mycorrhizal fungus, suggesting that there are complex interactions between defence genes and symbiosis genes during Endomycorrhiza establishment.
Vivienne Gianinazzi-pearson - One of the best experts on this subject based on the ideXlab platform.
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Comparison of acid soluble protein synthesis in roots of Endomycorrhizal wild type Pisum sativum and corresponding isogenic mutants
Journal of Plant Physiology, 2012Co-Authors: Luisa Schellenbaum, S. Gianinazzi, Vivienne Gianinazzi-pearsonAbstract:Summary The aim of this study was to compare profiles of acid soluble proteins in roots of Pisum sativum L. cv. Frisson and non-mycorrhizal mutants (myc − ) when infected by vesicular arbuscular mycorrhiza funghi. Quantitative and qualitative modifications were detected by native or SDS PAGE in the protein composition of acidic extracts of Endomycorrhizal roots of myc + , nod + wild type P. sativum and of a myc + , nod-mutant, as compared to uninoculated control plants or a myc − , nod − mutant, whether this was inoculated or not with Glomus mosseae . In native PAGE two proteins, already present in extracts of non-mycorrhizal pea roots, were enhanced in G. mosseae -infected myc + plants (nod + or nod − ). One protein which appeared after inoculation with G. mosseae or G. fasciculatum in the roots of all pea plants, including the myc − , nod − mutants, may be associated with appressorium formation. Four new proteins were detected in root extracts of G. mosseae -infected myc − peas (nod + or nod − ), as compared to the myc − , nod − mutant or uninoculated controls. One of these was probably of fungal origin, since it was also found in G. mosseae -infected tobacco and leek roots. These plants showed protein modifications different to those in Endomycorrhizal peas, suggesting host-specific responses. SDS PAGE revealed the presence of two polypeptides of about 25 and 35 kDa in Endomycorrhizal roots of myc + peas. None of the Endomycorrhiza-related proteins detected in roots corresponded to those extracted from spores of different fungi. This study provides new evidence that different molecular modifications occur during successful (myc + pea, leek, tobacco) and unsuccessful (myc − pea) Endomycorrhiza infections, some of which are host-determined and others related to the expression of the fungal genome.
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Techniques for the study of mycorrhiza. Vol. 2 - Cytology, Histochemistry and Immunocytochemistry as Tools for Studying Structure and Function in Endomycorrhiza
Methods in Microbiology, 2008Co-Authors: S. Gianinazzi, Vivienne Gianinazzi-pearsonAbstract:Publisher Summary This chapter describes some microscopical approaches for analyzing the structure of Endomycorrhizal infections, identifying modifications in protein expression (enzyme activities) and localizing specific molecules at both the tissue and cellular level. Techniques are chosen to illustrate how they can not only increase the understanding of how Endomycorrhizal symbionts interact with each other, but also furnish potential tools for diagnosing the functional state of the symbiosis. Non-destructive observations can be made of vesicular-arbuscular Endomycorrhizal infections in root pieces using ultraviolet light. Although this can be useful for selecting materials for biochemical analysis or electron microscope preparation, the technique is limited to young root tissues in which only living arbuscules can usually be detected. The chapter illustrates cytological, histochemical, and immunocytochemical techniques. It provides powerful tools for studying the structure and function of symbionts and their interactions in Endomycorrhiza. Knowledge of the physical and chemical nature of cellular and subcellular structures permitting functional compatability in Endomycorrhizal associations has been considerably improved and subcellular localization of enzyme activities has given some insight into their physiological significance for the symbiotic condition. Furthermore, by combining immunolocalization with ultra cytoenzymology it is possible to understand how the synthesis and the expression of the molecules involved are regulated.
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Localization of β (1–3) glucan in walls of the Endomycorrhizal fungi Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe during colonization of host roots
New Phytologist, 1995Co-Authors: M.-c. Lemoine, Armelle Gollotte, Vivienne Gianinazzi-pearsonAbstract:summary Previous studies showed that cell walls of Endomycorrhizal fungi belonging to the Acaulosporaceae and Glomaceae contain β (1–3) glucan polymers as well as chitin. Indirect immunolabelling with monoclonal and polyclonal antibodies has been used to investigate the distribution of these structural polysaccharides in cell walls of Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe and Acaulospora laevis Gerd. & Trappe as they interact with pea and tobacco roots, respectively. The (l-3) glucans were detected in the walls of external hyphae, and of hyphal coils and intercellular hyphae developing in outer root tissues. The glucan component was alkali-insoluble but treatment with chitinase resulted in solubilization of most of the β(1–3) glucans from the fungal wall. A decrease in immunolabelling was associated with thinning out of the hyphal wall as the fungi colonized deeper in the host root, and β(1–3) glucans could not be detected in walls of intercellular hyphae or arbuscules in the parenchyma cortical tissue. The molecular configuration of cell walls of G. mosseae and A. laevis is discussed in relation to fungal morphogenesis and the symbiotic state in Endomycorrhiza.
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Etude immunocytochimique des interfaces plante-champignon endomycorhizien à arbuscules chez des pois isogéniques myc+ ou résistant à l'endomycorhization (myc−)
Acta Botanica Gallica, 1994Co-Authors: Armelle Gollotte, Vivienne Gianinazzi-pearson, S. GianinazziAbstract:Summary Interactions between an arbuscular mycorrhizal fungus and pea cv. Frisson (myc+) or an isogenic mycorrhiza-resistant mutant (myc−) were investigated by immunocytochemistry. Observations of the presence of proteins and polysaccharides accumulating in other symbioses (pectins) or in plant-pathogenic interactions (PR-b1 protein, s-1,3-glucans) indicated a weak activation of defence mechanisms during establishment of symbiosis. In contrast, the myc mutant showed an important defence reaction against the mycorrhizal fungus, suggesting that there are complex interactions between defence genes and symbiosis genes during Endomycorrhiza establishment.
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Occurrence and expression of acid phosphatase of Hymenoscyphus ericae (Read) Korf & Kernan, in isolation or associated with plant roots
Mycorrhiza, 1992Co-Authors: M.-c. Lemoine, Vivienne Gianinazzi-pearson, S. Gianinazzi, C. J. StrakerAbstract:The activity of acid phosphatase produced in pure culture by the Endomycorrhizal fungus Hymenoscyphus ericae (Read) Korf & Kernan ( H. ericae LPA 2) was inhibited by high phosphorus levels, alkaline pH, fluoride, molybdate and mannosidase, and activated by concanavalin A. Over 80% of the enzyme activity was due to two wall-bound acid phosphatase isozymes with the characteristics of mannose-rich glycoproteins. Antiserum was raised against the major, low-molecular-weight wall isozyme and its activity tested by immunoblotting and ELISA. The antiserum cross reacted 100% with exocellular (excreted) and 28% with cytoplasmic cellular fractions of H. ericae (LPA 2) cultures, and showed high reactivity with other strains of H. ericae but not with fungal isolates from Erica hispidula L. or E. mauritanica L. Ultrastructural localization of acid phosphatase by cytoenzymology and indirect immunogold labelling confirmed its association with the fungal wall in pure culture and showed that the influence of a high phosphorus level, fluoride and molybdate is through inactivation of the enzyme. Intense acid phosphatase activity, sensitive to the latter inhibitors, was also present on external hyphae growing over a host or non-host root but it was weak or absent from intracellular hyphae where these developed within a host root. Indirect immunolabelling confirmed that this acid phosphatase was of fungal origin and that the specific inhibitory effect of host cells is due to inactivation of the enzyme rather than repression of its synthesis. Possible implications of fungal acid phosphatase in ericoid Endomycorrhizal infection processes are discussed together with mechanisms that may be regulating the enzyme activity.
C. J. Straker - One of the best experts on this subject based on the ideXlab platform.
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Occurrence and expression of acid phosphatase of Hymenoscyphus ericae (Read) Korf & Kernan, in isolation or associated with plant roots
Mycorrhiza, 1992Co-Authors: M.-c. Lemoine, Vivienne Gianinazzi-pearson, S. Gianinazzi, C. J. StrakerAbstract:The activity of acid phosphatase produced in pure culture by the Endomycorrhizal fungus Hymenoscyphus ericae (Read) Korf & Kernan ( H. ericae LPA 2) was inhibited by high phosphorus levels, alkaline pH, fluoride, molybdate and mannosidase, and activated by concanavalin A. Over 80% of the enzyme activity was due to two wall-bound acid phosphatase isozymes with the characteristics of mannose-rich glycoproteins. Antiserum was raised against the major, low-molecular-weight wall isozyme and its activity tested by immunoblotting and ELISA. The antiserum cross reacted 100% with exocellular (excreted) and 28% with cytoplasmic cellular fractions of H. ericae (LPA 2) cultures, and showed high reactivity with other strains of H. ericae but not with fungal isolates from Erica hispidula L. or E. mauritanica L. Ultrastructural localization of acid phosphatase by cytoenzymology and indirect immunogold labelling confirmed its association with the fungal wall in pure culture and showed that the influence of a high phosphorus level, fluoride and molybdate is through inactivation of the enzyme. Intense acid phosphatase activity, sensitive to the latter inhibitors, was also present on external hyphae growing over a host or non-host root but it was weak or absent from intracellular hyphae where these developed within a host root. Indirect immunolabelling confirmed that this acid phosphatase was of fungal origin and that the specific inhibitory effect of host cells is due to inactivation of the enzyme rather than repression of its synthesis. Possible implications of fungal acid phosphatase in ericoid Endomycorrhizal infection processes are discussed together with mechanisms that may be regulating the enzyme activity.
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occurrence and expression of acid phosphatase of hymenoscyphus ericae read korf kernan in isolation or associated with plant roots
Mycorrhiza, 1992Co-Authors: Marieclaude Lemoine, S. Gianinazzi, Vivienne Gianinazzipearson, C. J. StrakerAbstract:The activity of acid phosphatase produced in pure culture by the Endomycorrhizal fungus Hymenoscyphus ericae (Read) Korf & Kernan (H. ericae LPA 2) was inhibited by high phosphorus levels, alkaline pH, fluoride, molybdate and mannosidase, and activated by concanavalin A. Over 80% of the enzyme activity was due to two wall-bound acid phosphatase isozymes with the characteristics of mannose-rich glycoproteins. Antiserum was raised against the major, low-molecular-weight wall isozyme and its activity tested by immunoblotting and ELISA. The antiserum cross reacted 100% with exocellular (excreted) and 28% with cytoplasmic cellular fractions of H. ericae (LPA 2) cultures, and showed high reactivity with other strains of H. ericae but not with fungal isolates from Erica hispidula L. or E. mauritanica L. Ultrastructural localization of acid phosphatase by cytoenzymology and indirect immunogold labelling confirmed its association with the fungal wall in pure culture and showed that the influence of a high phosphorus level, fluoride and molybdate is through inactivation of the enzyme. Intense acid phosphatase activity, sensitive to the latter inhibitors, was also present on external hyphae growing over a host or non-host root but it was weak or absent from intracellular hyphae where these developed within a host root. Indirect immunolabelling confirmed that this acid phosphatase was of fungal origin and that the specific inhibitory effect of host cells is due to inactivation of the enzyme rather than repression of its synthesis. Possible implications of fungal acid phosphatase in ericoid Endomycorrhizal infection processes are discussed together with mechanisms that may be regulating the enzyme activity.