The Experts below are selected from a list of 126 Experts worldwide ranked by ideXlab platform

Susana Moreno Díaz De La Espina - One of the best experts on this subject based on the ideXlab platform.

  • Evolutionary history and structure of nuclear Matrix Constituent proteins, the plant analogues of lamins
    Journal of experimental botany, 2019
    Co-Authors: Malgorzata Ciska, Riku Hikida, Kiyoshi Masuda, Susana Moreno Díaz De La Espina
    Abstract:

    Nuclear Matrix Constituent proteins (NMCPs), the structural components of the plant lamina, are considered to be the analogues of lamins in plants based on numerous structural and functional similarities. Current phylogenetic knowledge suggests that, in contrast to lamins, which are widely distributed in eukaryotes, NMCPs are taxonomically restricted to Streptophyta. At present, most information about NMCPs comes from angiosperms, and virtually no data are available from more ancestral groups. In angiosperms, the NMCP family comprises two phylogenetic groups, NMCP1 and NMCP2, which evolved from the NMCP1 and NMCP2 progenitor genes. Based on sequence conservation and the presence of NMCP-specific domains, we determined the structure and number of NMCP genes present in different Streptophyta clades. We analysed 91 species of embryophytes and report additional NMCP sequences from mosses, liverworts, clubmosses, horsetail, ferns, gymnosperms, and Charophyta algae. Our results confirm an origin of NMCPs in Charophyta (the earliest diverging group of Streptophyta), resolve the number and structure of NMCPs in the different clades, and propose the emergence of additional NMCP homologues by whole-genome duplication events. Immunofluorescence microscopy demonstrated localization of a basal NMCP from the moss Physcomitrella patens at the nuclear envelope, suggesting a functional conservation for basal and more evolved NMCPs.

  • detection of endogenous nuclear proteins in plant cells localizing nuclear Matrix Constituent proteins nmcps the plant analogs of lamins
    Methods of Molecular Biology, 2017
    Co-Authors: Malgorzata Ciska, Susana Moreno Díaz De La Espina
    Abstract:

    At present, two complementary approaches are used for in situ protein visualization in plant nuclei. Imaging of transformed fluorescent proteins is the election tool for the analysis of protein movement and interaction. However, this methodology presents several drawbacks for the identification/localization of endogenous nuclear factors, such as over-expression or mislocalization of transformed proteins. In contrast, immunocytochemistry with specific antibodies represents a powerful tool for the localization of endogenous nuclear proteins at their "native" nuclear sub-compartments. In plant cells, the cell wall hampers antibody accessibility during immunocytochemical analysis thereby reducing the effectivity of the technique, particularly in the case of lowly expressed proteins. To overcome this problem in nuclear protein immunodetection, we developed a method based on the in vitro incubation of isolated nuclei with specific antibodies followed by imaging by confocal fluorescence or electron microscopy. Here we describe the application of this methodology to the localization of Nuclear Matrix Constituent Proteins (NMCP), the plant analogs of lamins, of the monocot Allium cepa, using antibodies raised against highly conserved regions of the proteins.

  • lamin like analogues in plants the characterization of nmcp1 in allium cepa
    Journal of Experimental Botany, 2013
    Co-Authors: Malgorzata Ciska, Kiyoshi Masuda, Susana Moreno Díaz De La Espina
    Abstract:

    : The nucleoskeleton of plants contains a peripheral lamina (also called plamina) and, even though lamins are absent in plants, their roles are still fulfilled in plant nuclei. One of the most intriguing topics in plant biology concerns the identity of lamin protein analogues in plants. Good candidates to play lamin functions in plants are the members of the NMCP (nuclear Matrix Constituent protein) family, which exhibit the typical tripartite structure of lamins. This paper describes a bioinformatics analysis and classification of the NMCP family based on phylogenetic relationships, sequence similarity and the distribution of conserved regions in 76 homologues. In addition, NMCP1 in the monocot Allium cepa characterized by its sequence and structure, biochemical properties, and subnuclear distribution and alterations in its expression throughout the root were identified. The results demonstrate that these proteins exhibit many similarities to lamins (structural organization, conserved regions, subnuclear distribution, and solubility) and that they may fulfil the functions of lamins in plants. These findings significantly advance understanding of the structural proteins of the plant lamina and nucleoskeleton and provide a basis for further investigation of the protein networks forming these structures.

Malgorzata Ciska - One of the best experts on this subject based on the ideXlab platform.

  • Evolutionary history and structure of nuclear Matrix Constituent proteins, the plant analogues of lamins
    Journal of experimental botany, 2019
    Co-Authors: Malgorzata Ciska, Riku Hikida, Kiyoshi Masuda, Susana Moreno Díaz De La Espina
    Abstract:

    Nuclear Matrix Constituent proteins (NMCPs), the structural components of the plant lamina, are considered to be the analogues of lamins in plants based on numerous structural and functional similarities. Current phylogenetic knowledge suggests that, in contrast to lamins, which are widely distributed in eukaryotes, NMCPs are taxonomically restricted to Streptophyta. At present, most information about NMCPs comes from angiosperms, and virtually no data are available from more ancestral groups. In angiosperms, the NMCP family comprises two phylogenetic groups, NMCP1 and NMCP2, which evolved from the NMCP1 and NMCP2 progenitor genes. Based on sequence conservation and the presence of NMCP-specific domains, we determined the structure and number of NMCP genes present in different Streptophyta clades. We analysed 91 species of embryophytes and report additional NMCP sequences from mosses, liverworts, clubmosses, horsetail, ferns, gymnosperms, and Charophyta algae. Our results confirm an origin of NMCPs in Charophyta (the earliest diverging group of Streptophyta), resolve the number and structure of NMCPs in the different clades, and propose the emergence of additional NMCP homologues by whole-genome duplication events. Immunofluorescence microscopy demonstrated localization of a basal NMCP from the moss Physcomitrella patens at the nuclear envelope, suggesting a functional conservation for basal and more evolved NMCPs.

  • detection of endogenous nuclear proteins in plant cells localizing nuclear Matrix Constituent proteins nmcps the plant analogs of lamins
    Methods of Molecular Biology, 2017
    Co-Authors: Malgorzata Ciska, Susana Moreno Díaz De La Espina
    Abstract:

    At present, two complementary approaches are used for in situ protein visualization in plant nuclei. Imaging of transformed fluorescent proteins is the election tool for the analysis of protein movement and interaction. However, this methodology presents several drawbacks for the identification/localization of endogenous nuclear factors, such as over-expression or mislocalization of transformed proteins. In contrast, immunocytochemistry with specific antibodies represents a powerful tool for the localization of endogenous nuclear proteins at their "native" nuclear sub-compartments. In plant cells, the cell wall hampers antibody accessibility during immunocytochemical analysis thereby reducing the effectivity of the technique, particularly in the case of lowly expressed proteins. To overcome this problem in nuclear protein immunodetection, we developed a method based on the in vitro incubation of isolated nuclei with specific antibodies followed by imaging by confocal fluorescence or electron microscopy. Here we describe the application of this methodology to the localization of Nuclear Matrix Constituent Proteins (NMCP), the plant analogs of lamins, of the monocot Allium cepa, using antibodies raised against highly conserved regions of the proteins.

  • lamin like analogues in plants the characterization of nmcp1 in allium cepa
    Journal of Experimental Botany, 2013
    Co-Authors: Malgorzata Ciska, Kiyoshi Masuda, Susana Moreno Díaz De La Espina
    Abstract:

    : The nucleoskeleton of plants contains a peripheral lamina (also called plamina) and, even though lamins are absent in plants, their roles are still fulfilled in plant nuclei. One of the most intriguing topics in plant biology concerns the identity of lamin protein analogues in plants. Good candidates to play lamin functions in plants are the members of the NMCP (nuclear Matrix Constituent protein) family, which exhibit the typical tripartite structure of lamins. This paper describes a bioinformatics analysis and classification of the NMCP family based on phylogenetic relationships, sequence similarity and the distribution of conserved regions in 76 homologues. In addition, NMCP1 in the monocot Allium cepa characterized by its sequence and structure, biochemical properties, and subnuclear distribution and alterations in its expression throughout the root were identified. The results demonstrate that these proteins exhibit many similarities to lamins (structural organization, conserved regions, subnuclear distribution, and solubility) and that they may fulfil the functions of lamins in plants. These findings significantly advance understanding of the structural proteins of the plant lamina and nucleoskeleton and provide a basis for further investigation of the protein networks forming these structures.

Tom Van De Wiele - One of the best experts on this subject based on the ideXlab platform.

  • isolation and characterization of human intestinal bacteria capable of transforming the dietary carcinogen 2 amino 1 methyl 6 phenylimidazo 4 5 b pyridine
    Applied and Environmental Microbiology, 2008
    Co-Authors: Lynn Vanhaecke, Filip Vercruysse, Nico Boon, Willy Verstraete, Ilse Cleenwerck, Marjan De Wachter, Paul De Vos, Tom Van De Wiele
    Abstract:

    2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a carcinogenic heterocyclic aromatic amine formed in meat products during cooking. Although the formation of hazardous PhIP metabolites by mammalian enzymes has been extensively reported, research on the putative involvement of the human intestinal microbiota in PhIP metabolism remains scarce. In this study, the in vitro conversion of PhIP into its microbial derivate, 7-hydroxy-5-methyl-3-phenyl-6,7,8,9-tetrahydropyrido[3',2':4,5]imidazo[1,2-a]pyrimidin-5-ium chloride (PhIP-M1), by fecal samples from 18 human volunteers was investigated. High-performance liquid chromatography analysis showed that all human fecal samples transformed PhIP but with efficiencies ranging from 1.8 to 96% after 72 h of incubation. Two PhIP-transforming strains, PhIP-M1-a and PhIP-M1-b, were isolated from human feces and identified by fluorescent amplified fragment length polymorphism and pheS sequence analyses as Enterococcus faecium strains. Some strains from culture collections belonging to the species E. durans, E. avium, E. faecium, and Lactobacillus reuteri were also able to perform this transformation. Yeast extract, special peptone, and meat extract supported PhIP transformation by the enriched E. faecium strains, while tryptone, monomeric sugars, starch, and cellulose did not. Glycerol was identified as a fecal Matrix Constituent required for PhIP transformation. Abiotic synthesis of PhIP-M1 and quantification of the glycerol metabolite 3-hydroxypropionaldehyde (3-HPA) confirmed that the anaerobic fermentation of glycerol via 3-HPA is the critical bacterial transformation process responsible for the formation of PhIP-M1. Whether it is a detoxification is still a matter of debate, since PhIP-M1 has been shown to be cytotoxic toward Caco-2 cells but is not mutagenic in the Ames assay.

Chang Liu - One of the best experts on this subject based on the ideXlab platform.

  • characterization of a plant nuclear Matrix Constituent protein in liverwort
    Frontiers in Plant Science, 2021
    Co-Authors: Nan Wang, Ezgi Suheyla Karaaslan, Natalie Faiss, Kenneth W Berendzen, Chang Liu
    Abstract:

    The nuclear lamina (NL) is a complex network of nuclear lamins and lamina-associated nuclear membrane proteins, which scaffold the nucleus to maintain structural integrity. In animals, type V intermediate filaments are the main Constituents of NL. Plant genomes do not encode any homologs of these intermediate filaments, yet plant nuclei contain lamina-like structures that are present in their nuclei. In Arabidopsis thaliana, CROWDED NUCLEI (CRWN), which are required for maintaining structural integrity of the nucleus and specific perinuclear chromatin anchoring, are strong candidates for plant lamin proteins. Recent studies revealed additional roles of Arabidopsis Nuclear Matrix Constituent Proteins (NMCPs) in modulating plants' response to pathogen and abiotic stresses. However, detailed analyses of Arabidopsis NMCP activities are challenging due to the presence of multiple homologs and their functional redundancy. In this study, we investigated the sole NMCP gene in the liverwort Marchantia polymorpha (MpNMCP). We found that MpNMCP proteins preferentially were localized to the nuclear periphery. Using CRISPR/Cas9 techniques, we generated an MpNMCP loss-of-function mutant, which displayed reduced growth rate and curly thallus lobes. At an organelle level, MpNMCP mutants did not show any alteration in nuclear morphology. Transcriptome analyses indicated that MpNMCP was involved in regulating biotic and abiotic stress responses. Additionally, a highly repetitive genomic region on the male sex chromosome, which was preferentially tethered at the nuclear periphery in wild-type thalli, decondensed in the MpNMCP mutants and located in the nuclear interior. This perinuclear chromatin anchoring, however, was not directly controlled by MpNMCP. Altogether, our results unveiled that NMCP in plants have conserved functions in modulating stress responses.

J Bonhomme - One of the best experts on this subject based on the ideXlab platform.

  • influence of the Matrix Constituent on mode i and mode ii delamination toughness in fiber reinforced polymer composites under cyclic fatigue
    Mechanics of Materials, 2011
    Co-Authors: A Arguelles, J Vina, Alfonso Fernandezcanteli, I Vina, J Bonhomme
    Abstract:

    Abstract Mode I and mode II fracture behaviour under static and dynamic loading was analyzed in two composites made up of the same reinforcement though embedded in two different matrices. Specifically, the delamination energy under static and dynamic loading was obtained for both materials and both fracture modes, i.e. the number of cycles necessary for the onset of fatigue delamination. Subsequently, the crack growth rate (delamination rate) was obtained for different percentages of the critical energy rate. The main goal of the study was to ascertain the influence of the Matrix on the behaviour of the laminate under fatigue loading. From the experimental results for the onset of delamination, similar fatigue behaviour was observed at a low number of cycles for both matrices and both fracture modes, while in fatigue at a high number of cycles, a higher fatigue limit was obtained in the composite with the modified resin (higher toughness) for both fracture modes. From the point of view of crack growth rate, both materials behaved similarly for different levels of stress under fatigue and the two fracture modes for small crack lengths (initial growth zone