The Experts below are selected from a list of 135 Experts worldwide ranked by ideXlab platform

Philippe Rott - One of the best experts on this subject based on the ideXlab platform.

  • breaking dogmas the Plant vascular pathogen xanthomonas albilineans is able to invade non vascular tissues despite its reduced genome
    Open Biology, 2014
    Co-Authors: Imene Mensi, Daniel Gargani, Marie-stéphanie Vernerey, Michel Nicole, Philippe Rott
    Abstract:

    Xanthomonas albilineans, the causal agent of sugarcane leaf scald, is missing the Hrp type III secretion system that is used by many Gram-negative bacteria to colonize their host. Until now, this pathogen was considered as strictly limited to the xylem of sugarcane. We used confocal laser scanning microscopy, immunocytochemistry and transmission electron microscopy (TEM) to investigate the localization of X. albilineans in diseased sugarcane. Sugarcane Plants were inoculated with strains of the pathogen labelled with a green fluorescent protein. Confocal microscopy observations of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and metaxylem; however, X. albilineans was also observed in phloem, parenchyma and bulliform cells of the infected leaves. Similarly, vascular bundles of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in intercellular spaces between these cells. Most of these observations made by confocal microscopy were confirmed by TEM. The pathogen exits the xylem following cell wall and middle lamellae degradation, thus creating openings to reach parenchyma cells. This is the first description of a Plant pathogenic vascular bacterium invading apparently intact Non-Vascular Plant tissues and multiplying in parenchyma cells.

  • Xanthomonas albilineans is able to move outside of the sugarcane xylem despite its reduced genome and the absence of a Hrp type III secretion system
    2012
    Co-Authors: Imene Mensi, Daniel Gargani, Marie-stéphanie Vernerey, Philippe Rott
    Abstract:

    Xanthomonas albilineans, the causal agent of leaf scald disease of sugarcane, is a pathogen that experienced genome reduction during its speciation. Additionally, this xanthomonad is notably missing the Hrp type III secretion system and the xanthan gene cluster that are commonly found in pathogenic Xanthomonas species. X. albilineans was up to now considered as limited to the xylem of sugarcane. However, recently published studies suggested that X. albilineans was able to invade tissues other than the xylem of sugarcane leaves but the occurrence of X. albilineans outside the xylem has not been clearly proven. In this study, we used confocal microscopy and transmission electron microscopy to investigate the localization of this pathogen in diseased leaves and stalks of sugarcane. Three sugarcane cultivars with different levels of resistance to leaf scald were inoculated with the green fluorescent protein labelled X. albilineans strains XaFL07-1 (from Florida) and GPE PC73 (from Guadeloupe). Sections of sugarcane leaves and stalks were examined 8-60 days after inoculation in order to localize X. albilineans in the different Plant tissues. Confocal microscopy observation of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and the metaxylem, however, X. albilineans was also observed in the phloem, the parenchyma and the bulliform cells of the leaves. Similarly, the protoxylem and the metaxylem of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in the intercellular spaces between these cells. Several of these observations made by confocal microscopy have been confirmed by transmission electron microscopy. X. albilineans can therefore no longer be considered as a xylem-limited pathogen. To our knowledge, this is the first description of a Plant pathogenic bacterium invading apparently intact Non-Vascular Plant tissue and multiplying in parenchyma cells. The mechanisms and virulence factors used by X. albilineans to enter and invade different tissues of sugarcane remain to be identified

Fabien Nogué - One of the best experts on this subject based on the ideXlab platform.

  • Physcomitrella patens: a Non-Vascular Plant for recombinant protein production.
    Methods in molecular biology (Clifton N.J.), 2009
    Co-Authors: David Lienard, Fabien Nogué
    Abstract:

    The moss Physcomitrella patens is a long-standing model for studying Plant development, growth and cell differentiation in particular. Interest in this Non-Vascular Plant arose following the discovery that homologous recombination is an efficient process. P. patens is, therefore, a tool of choice not only to study gene function but also for recombinant protein production. This system has many attributes that are advantageous for molecular farming: protein production in cell suspension, the possibility of generating targeted knockout mutants for glycoengineering and quantitative optimization for protein production. In terms of technical advances, P. patens is one of the most up-to-date Plant expression systems and is a promising alternative to animal cell factories for the production of therapeutic proteins with either simple or highly complex structures.

Imene Mensi - One of the best experts on this subject based on the ideXlab platform.

  • breaking dogmas the Plant vascular pathogen xanthomonas albilineans is able to invade non vascular tissues despite its reduced genome
    Open Biology, 2014
    Co-Authors: Imene Mensi, Daniel Gargani, Marie-stéphanie Vernerey, Michel Nicole, Philippe Rott
    Abstract:

    Xanthomonas albilineans, the causal agent of sugarcane leaf scald, is missing the Hrp type III secretion system that is used by many Gram-negative bacteria to colonize their host. Until now, this pathogen was considered as strictly limited to the xylem of sugarcane. We used confocal laser scanning microscopy, immunocytochemistry and transmission electron microscopy (TEM) to investigate the localization of X. albilineans in diseased sugarcane. Sugarcane Plants were inoculated with strains of the pathogen labelled with a green fluorescent protein. Confocal microscopy observations of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and metaxylem; however, X. albilineans was also observed in phloem, parenchyma and bulliform cells of the infected leaves. Similarly, vascular bundles of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in intercellular spaces between these cells. Most of these observations made by confocal microscopy were confirmed by TEM. The pathogen exits the xylem following cell wall and middle lamellae degradation, thus creating openings to reach parenchyma cells. This is the first description of a Plant pathogenic vascular bacterium invading apparently intact Non-Vascular Plant tissues and multiplying in parenchyma cells.

  • Xanthomonas albilineans is able to move outside of the sugarcane xylem despite its reduced genome and the absence of a Hrp type III secretion system
    2012
    Co-Authors: Imene Mensi, Daniel Gargani, Marie-stéphanie Vernerey, Philippe Rott
    Abstract:

    Xanthomonas albilineans, the causal agent of leaf scald disease of sugarcane, is a pathogen that experienced genome reduction during its speciation. Additionally, this xanthomonad is notably missing the Hrp type III secretion system and the xanthan gene cluster that are commonly found in pathogenic Xanthomonas species. X. albilineans was up to now considered as limited to the xylem of sugarcane. However, recently published studies suggested that X. albilineans was able to invade tissues other than the xylem of sugarcane leaves but the occurrence of X. albilineans outside the xylem has not been clearly proven. In this study, we used confocal microscopy and transmission electron microscopy to investigate the localization of this pathogen in diseased leaves and stalks of sugarcane. Three sugarcane cultivars with different levels of resistance to leaf scald were inoculated with the green fluorescent protein labelled X. albilineans strains XaFL07-1 (from Florida) and GPE PC73 (from Guadeloupe). Sections of sugarcane leaves and stalks were examined 8-60 days after inoculation in order to localize X. albilineans in the different Plant tissues. Confocal microscopy observation of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and the metaxylem, however, X. albilineans was also observed in the phloem, the parenchyma and the bulliform cells of the leaves. Similarly, the protoxylem and the metaxylem of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in the intercellular spaces between these cells. Several of these observations made by confocal microscopy have been confirmed by transmission electron microscopy. X. albilineans can therefore no longer be considered as a xylem-limited pathogen. To our knowledge, this is the first description of a Plant pathogenic bacterium invading apparently intact Non-Vascular Plant tissue and multiplying in parenchyma cells. The mechanisms and virulence factors used by X. albilineans to enter and invade different tissues of sugarcane remain to be identified

David Lienard - One of the best experts on this subject based on the ideXlab platform.

  • Physcomitrella patens: a Non-Vascular Plant for recombinant protein production.
    Methods in molecular biology (Clifton N.J.), 2009
    Co-Authors: David Lienard, Fabien Nogué
    Abstract:

    The moss Physcomitrella patens is a long-standing model for studying Plant development, growth and cell differentiation in particular. Interest in this Non-Vascular Plant arose following the discovery that homologous recombination is an efficient process. P. patens is, therefore, a tool of choice not only to study gene function but also for recombinant protein production. This system has many attributes that are advantageous for molecular farming: protein production in cell suspension, the possibility of generating targeted knockout mutants for glycoengineering and quantitative optimization for protein production. In terms of technical advances, P. patens is one of the most up-to-date Plant expression systems and is a promising alternative to animal cell factories for the production of therapeutic proteins with either simple or highly complex structures.

Daniel Gargani - One of the best experts on this subject based on the ideXlab platform.

  • breaking dogmas the Plant vascular pathogen xanthomonas albilineans is able to invade non vascular tissues despite its reduced genome
    Open Biology, 2014
    Co-Authors: Imene Mensi, Daniel Gargani, Marie-stéphanie Vernerey, Michel Nicole, Philippe Rott
    Abstract:

    Xanthomonas albilineans, the causal agent of sugarcane leaf scald, is missing the Hrp type III secretion system that is used by many Gram-negative bacteria to colonize their host. Until now, this pathogen was considered as strictly limited to the xylem of sugarcane. We used confocal laser scanning microscopy, immunocytochemistry and transmission electron microscopy (TEM) to investigate the localization of X. albilineans in diseased sugarcane. Sugarcane Plants were inoculated with strains of the pathogen labelled with a green fluorescent protein. Confocal microscopy observations of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and metaxylem; however, X. albilineans was also observed in phloem, parenchyma and bulliform cells of the infected leaves. Similarly, vascular bundles of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in intercellular spaces between these cells. Most of these observations made by confocal microscopy were confirmed by TEM. The pathogen exits the xylem following cell wall and middle lamellae degradation, thus creating openings to reach parenchyma cells. This is the first description of a Plant pathogenic vascular bacterium invading apparently intact Non-Vascular Plant tissues and multiplying in parenchyma cells.

  • Xanthomonas albilineans is able to move outside of the sugarcane xylem despite its reduced genome and the absence of a Hrp type III secretion system
    2012
    Co-Authors: Imene Mensi, Daniel Gargani, Marie-stéphanie Vernerey, Philippe Rott
    Abstract:

    Xanthomonas albilineans, the causal agent of leaf scald disease of sugarcane, is a pathogen that experienced genome reduction during its speciation. Additionally, this xanthomonad is notably missing the Hrp type III secretion system and the xanthan gene cluster that are commonly found in pathogenic Xanthomonas species. X. albilineans was up to now considered as limited to the xylem of sugarcane. However, recently published studies suggested that X. albilineans was able to invade tissues other than the xylem of sugarcane leaves but the occurrence of X. albilineans outside the xylem has not been clearly proven. In this study, we used confocal microscopy and transmission electron microscopy to investigate the localization of this pathogen in diseased leaves and stalks of sugarcane. Three sugarcane cultivars with different levels of resistance to leaf scald were inoculated with the green fluorescent protein labelled X. albilineans strains XaFL07-1 (from Florida) and GPE PC73 (from Guadeloupe). Sections of sugarcane leaves and stalks were examined 8-60 days after inoculation in order to localize X. albilineans in the different Plant tissues. Confocal microscopy observation of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and the metaxylem, however, X. albilineans was also observed in the phloem, the parenchyma and the bulliform cells of the leaves. Similarly, the protoxylem and the metaxylem of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in the intercellular spaces between these cells. Several of these observations made by confocal microscopy have been confirmed by transmission electron microscopy. X. albilineans can therefore no longer be considered as a xylem-limited pathogen. To our knowledge, this is the first description of a Plant pathogenic bacterium invading apparently intact Non-Vascular Plant tissue and multiplying in parenchyma cells. The mechanisms and virulence factors used by X. albilineans to enter and invade different tissues of sugarcane remain to be identified