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Changes in Cinnamic Acid Derivatives Associated with the Habituation of Maize Cells to Dichlobenil

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Molecular Plant 2011年第5期4卷 869-878页

作者： Hugo Melida jesus Alvarez jose Luis Acebes Antonio encina Stephen C. Fry Area de Fisiologia Vegetal Facultad de CC Biologicas y Ambientales Universidad de Leon E-24071 Leon Spain Edinburgh Cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences University of Edinburgh Daniel Rutherford Building The King＇s Buildings Edinburgh EH9 3JH UK

The habituation of cell cultures to cellulose biosynthesis inhibitors such as dichlobenil （DCB） represents a valu- able tool to improve our knowledge of the mechanisms involved in plant cell wall structural plasticity. Maize cell lines habituated to lethal concentrations of DCB were able to grow through the acquisition of a modified cell wall in which cellulose was partially replaced by a more extensive network of arabinoxylans. The aim of this work was to investigate the phenolic metabolism of non-habituated and DCB-habituated maize cell cultures. Maize cell cultures were fed [14C]cinnamate and the fate of the radioactivity in different intra-protoplasmic and wall-localized fractions throughout the culture cycle was analyzed by autoradiography and scintillation counting. Non-habituated and habituated cultures did not markedly differ in their ability to uptake exogenous [14C]cinnamic acid. However, interesting differences were found in the radiolabeling of low- and high-Mr metabolites. Habituated cultures displayed a higher number and amount of radiola-beled low-Mr compounds, which could act as reserves later used for polysaccharide feruloylation. DCB-habituated cultures were highly enriched in esterified [14C]dehydrodiferulates and larger coupling products. In conclusion, an extensive and early cross-linking of hydroxycinnamates was observed in DCB-habituated cultures, probably strengthening their cellulose-deficient walls.

关键词： Cell wall Zea mays maize dichlobenil DCB dehydrodiferulate ferulate cinnamic acid.

Unraveling the Biochemical and Molecular Networks Involved in Maize Cell Habituation to the Cellulose Biosynthesis Inhibitor Dichlobenil

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Molecular Plant 2010年第5期3卷 842-853页

作者： Hugo Melida Antonio encina jesus Alvarez jose Luis Acebes David Caparros-Ruiz Area de Fisiologia Vegetal Facultad de CC. Biologicas y Ambientales Universidad de Leon E-24071 Leon Spain Centre de Recerca en AgriGen6mica (Consorci CSIC-IRTA-UAB) Jordi Girona 18-26 E-08034 Barcelona Spain

The biochemical and molecular processes involved in the habituation of maize cells to growth in the presence of the cellulose biosynthesis inhibitor dichlobenil （DCB） were investigated. DCB affects the synthesis of cellulose both in active and stationary growth phases and alters the expression of several CesA genes. Of these, ZmCesA5 and ZmCesA7 seem to play a major role in habituating cells to growth in the presence of DCB. As a consequence of the reduction in cellulose, the expression of several genes involved in the synthesis of hydroxycinnamates is increased, resulting in cell walls with higher levels of ferulic and p-coumaric acids. A proteomic analysis revealed that habituation to DCB is linked to modifications in several metabolic pathways. Finally, habituated cells present a reduction in glutathione S-transferase detoxifying activity and antioxidant activities. Plant cell adaptation to the disturbance of such a crucial process as cellulose biosynthesis requires changes in several metabolic networks, in order to modify cell wall architecture and metabolism, and survive in the presence of the inhibitor. Some of these modifications are described in this paper.

关键词： Abiotic/environmental stress acclimation--physiological cell walls maize cellulose dichlobenil phenylpropanoid.

Plasticity of Xyloglucan Composition in Bean （Phaseolus vulgaris）-Cultured Cells during Habituation and Dehabituation to Lethal Concentrations of Dichlobenil

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Molecular Plant 2010年第3期3卷 603-609页

作者： A. Alonso-Simon L. Neumetzler R Garcia-Angulo A.E. encina j.L. Acebes j.M. Alvarez T. Hayashi Area de Fisiologia Vegetal Universidad de Leon E-24071 Leon Spain Max Planck Institute of Molecular Plant Physiology 14476 Golm Germany Kyoto University RISH Gokasho Uji Kyoto 611-0011 Japan

Bean cells that have been habituated to grow in a lethal concentration （12 μM） of 2,6-dichlorobenzonitrile （dichlobenil or DCB, a cellulose biosynthesis inhibitor） are known to have decreased cellulose content in their cell walls. Xyloglucan, which is bound to cellulose and together with it forms the main loading network of plant cell walls, has also been described to decrease in habituated cells, but whether the change on cellulose affects the xyloglucan structure besides its abundance has not been analyzed. Fragmentation analysis with xyloglucan-specific endoglucanase （XEG） and endocellulase revealed that habituation to DCB caused a change in the fine structure of xyloglucan, namely a decrease in fucosyl residues attached to the galactosyl-xylosyl residues along the glucan backbone. After the removal of herbicide from the medium （dehabituated cells）, xyloglucan recovered its fucosyl residues. In addition, some cello-oligosaccharides could be detected only in habituated cells＇ xyloglucan digested by XEG and endocellulase, corresponding to a glucan co- valently bound or co-precipitated with the hemicelluloses. These results show that structural flexibility of cell walls relies in part on the plasticity of xyloglucan composition and opens up new perspectives to further research in this field.

关键词： Bean 2,6-dichlorobenzonitrile habituation and dehabituation OLIMP (Oligosaccharides Mass Profiling) xyloglucan.

Effects of vegetation strata and human disturbance on bird diversity in green areas in a city in southern Chile

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Avian Research 2018年第4期9卷 329-343页

作者： Andrés Munoz-Pedreros Marilyn González-Urrutia Francisco encina-Montoya Heraldo V.Norambuena Núcleo de Investigación en Estudios Ambientales NEA Departamento de Ciencias AmbientalesFacultad de Recursos NaturalesUniversidad Católica de TemucoCasilla 15.DTemucoChile Programa de Biodiversidad y Manejo de Vida Silvestre Centro de Estudios Agrarios y AmbientalesCasilla 164ValdiviaChile

Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green areas, including original fragments, can help to conserve native diversity, improving the functioning of these artificial systems in the long term. Urban areas can still provide habitats usable by wild birds, however the structural charac?teristics of the habitat formed by different types of green area differ, and therefore dissimilar bird diversities are to be expected. The object of this study was to characterise the α and β diversities of birds in different green areas and to analyse how diversity relates to ten variables that characterise the ***: We studied the green areas in the city of Temuco, southern Chile(Park, Square and Median strips of main streets), evaluating the variables:(a) surface area,(b) vegetation,(c) estimated human impact as the proportions of vegetation and bare soil by area, and the vehicle traffic. The bird assemblage structures were characterised by α(intra?environment) diversity and β diversity(between environments) and the statistical analysis identified the environmen?tal variables related with the presence and abundance of birds. A statistical model was constructed to describe the contribution of the variables to bird ***: We found significant differences between the diversity of bird species in the three types of green area. The β showed medium to high similarity between the different study units. There was a negative correlation with bare soil areas; the correlations with vehicle flow, plant structure and tree and shrub cover were not significant, meaning that these variables did not explain the variation in the richness of bird species between the green areas. However the surface area did explain this variation presenting a positive potential relation. There was also a high correlation with the o

关键词： Urban birds Urban green area Vegetation structure Bird composition Chile

Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells

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journal of Integrative Plant Biology 2017年第7期59卷 475-495页

作者： María de Castro Romina Martínez-Rubio josé L.Acebes Antonio encina Stephen C.Fry Penélope García-Angulo área de Fisiología Vegetal.Dpto.Ingenieríay Ciencias Agrarias.Facultad de Biologíay Ciencias Ambientales.Universidad de León The Edinburgh Cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences Daniel Rutherford BuildingThe King's Buildings

As a consequence of the habituation to low levels of dichlobenil （DCB）, cultured maize cells presented an altered hemicellulose cell fate with a lower proportion of strongly wall-bound hemicelluloses and an increase in soluble extracellular polymers released into the culture medium. The aim of this study was to investigate the relative molecular mass distributions of polysaccharides as well as phenolic metabolism in cells habituated to low levels of DCB （1.5 μM）. Generally, cell wall bound hemicelluloses and sloughed polymers from habituated cells were more homogeneously sized and had a lower weight-average relative molecular mass. In addition, polysaccharides underwent massive cross-linking after being secreted into the cell wall, but this cross-linking was less pronounced in habituated cells than in non-habituated ones. However, when relativized, ferulic acid and p-coumaric acid contents were higher in this habituated cell line. Feasibly, cells habituated to low levels of DCB synthesized molecules with a lower weight-average relative molecular mass, although cross-linked, as a part of their strategy to compensate for the lack of cellulose.

关键词： Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells were for

The biosynthesis and wall-binding of hemicelluloses in cellulose-deficient maize cells:An example of metabolic plasticity

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journal of Integrative Plant Biology 2015年第4期57卷 373-387页

作者： María de Castro janice G.Miller josé Luis Acebes Antonio encina Penélope García-Angulo Stephen C.Fry The Edinburgh Cell Wall Group Institute of Molecular Plant SciencesSchool of Biological SciencesDaniel Rutherford BuildingThe King's Buildings Laboratory of Plant Physiology Faculty of Biological and Environmental SciencesUniversity of Léon

Cell-suspension cultures（Zea mays L.,Black Mexican sweet corn） habituated to 2,6-dichlorobenzonitrile（DCB） survive with reduced cellulose owing to hemicellulose network modification. We aimed to de fine the hemicellulose metabolism modifications in DCB-habituated maize cells showing a mild reduction in cellulose at different stages in the culture cycle. Using pulse-chase radiolabeling, we fed habituated and non-habituated cultures with [3H]arabinose,and traced the distribution of 3H-pentose residues between xylans, xyloglucans and other polymers in several cellular compartments for 5 h. Habituated cells were slower taking up exogenous [3H]arabinose. Tritium was incorporated into polysaccharide-bound arabinose and xylose residues, but habituated cells diverted a higher proportion of their new [3H]xylose residues into（hetero） xylans at the expense of xyloglucan synthesis. During logarithmic growth, habituated cells showed slower vesicular traf ficking of polymers,especially xylans. Moreover, habituated cells showed a decrease in the strong wall-binding of all pentose-containing polysaccharides studied; correspondingly, especially in log phase cultures, habituation increased the proportion of 3H-hemicelluloses（[3H]xylans and [3H]xyloglucan） sloughed into the medium. These findings could be related to the cel walls’ cellulose-deficiency, and consequent reduction in binding sites for hemicelluloses; the data could also re fl ect the habituated cells’ reduced capacity to integrate arabinox ylans by extra-protoplasmic phenolic cross-linking, as well as xyloglucans, during wall assembly.

关键词： Arabinoxylan cell wall cross-linking 2,6-dichlorobenzonitrile Hemicellulose biosynthesis xyloglucan

Altered Lignin Biosynthesis Improves Cellulosic Bioethanol Production in Transgenic Maize Plants Down-Regulated for Cinnamyl Alcohol Dehydrogenase

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Molecular Plant 2012年第4期5卷 817-830页

作者： Silvia Fornale Montserrat Capellades Antonio encina Kan Wang Sami Irara Catherine Lapierre Katia Ruel jean-Paul joseleaue jordi Berenguer Pere Puigdomenech joan Rigau David Caparros-Ruiz Laboratori de Genetica Molecular Vegetal Centre de Recerca en AgriGenomica (CRAG) Consorci CSIC-IRTA-UAB-UB Edifici CRAG Campus UAB Bellaterra (Cerdanyola del Valles) 08193 Barcelona Spain Area de Fisiologia Vegetal Universidad de Lean 24071 Spain Center for Plant Transformation Iowa State University G405 Agronomy Hall Ames IA 50011-1010 USA Institut jean-Pierre Bourgin INRA-AgroParisTech UMR 1318 78026 Versailles cedex France Centre de Recherches sur les Macromolecules Vegetales-UPR-CNRS-5301 38041 Grenoble Cedex 09 France

Cinnamyl alcohol dehydrogenase （CAD） is a key enzyme involved in the last step of monolignol biosynthesis. The effect of CAD down-regulation on lignin production was investigated through a transgenic approach in maize. Trans- genic CAD-RNAi plants show a different degree of enzymatic reduction depending on the analyzed tissue and show alter- ations in cell wall composition. Cell walls of CAD-RNAi stems contain a lignin polymer with a slight reduction in the S-to-G ratio without affecting the total lignin content. In addition, these cell walls accumulate higher levels of cellulose and ara- binoxylans. In contrast, cell walls of CAD-RNAi midribs present a reduction in the total lignin content and of cell wall polysaccharides. In vitro degradability assays showed that, although to a different extent, the changes induced by the repression of CAD activity produced midribs and stems more degradable than wild-type plants. CAD-RNAi plants grown in the field presented a wild-type phenotype and produced higher amounts of dry biomass. Cellulosic bioethanol assays revealed that CAD-RNAi biomass produced higher levels of ethanol compared to wild-type, making CAD a good target to improve both the nutritional and energetic values of maize lignocellulosic biomass.

关键词： Maize lignification lignocellulosic biomass secondary cell wall.

Ectopic lignification in primary cellulose-deficient cell walls of maize cell suspension cultures

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journal of Integrative Plant Biology 2015年第4期57卷 357-372页

作者： Hugo Mélida Asier Largo-Gosens Esther Novo-Uzal Rogelio Santiago Federico Pomar Pedro García Penélope García-Angulo josé Luis Acebes jesús álvarez Antonio encina Plant Physiology Laboratory Faculty of Biological and Environmental SciencesUniversity of León Centre for Plant Biotechnology and Genomics (CBGP) Politechnical University of Madrid Department of Plant Biology University of Murcia Plant Biology and Soil Sciences Department Faculty of BiologyUniversity of Vigo Environmental Agrobiology Soil and Plant Quality (University of Vigo)Associated Unit to Biological Mission of Galicia (CSIC) Department of Animal Biology Plant Biology and EcologyUniversity of A Coru?a Department of Molecular Biology(área de Genética) Faculty of Biological and Environmental SciencesUniversity of León

Maize （Zea mays L.） suspension-cultured cells with up to 7o% less cellulose were obtained by stepwise habituation to dichlobenil （DCB）, a cellulose biosynthesis inhibitor. Cellulose deficiency was accompanied by marked changes in cell wall matrix polysaccharides and phenolics as revealed by Fourier transform infrared （FTIR） spectroscopy. Cell wall compositional analysis indicated that the cellulosedeficient cell walls showed an enhancement of highly branched and cross-linked arabinoxylans, as well as an increased content in ferulic acid, diferulates and p-coumaric acid, and the presence of a polymer that stained positive for phloroglucinol. In accordance with this, cellulose-deficient cell walls showed a fivefold increase in Klason-type lignin. Thioacidolysis/GC-MS analysis of cellulose-deficient cell walls indicated the presence of a lignin-like polymer with a Syringyl/Guaiacyl ratio of 1.45, which differed from the sensu stricto stress-related lignin that arose in response to shortterm DCB-treatments. Gene expression analysis of these ceils indicated an overexpression of genes specific for the biosynthesis of monolignol units of lignin. A study of stress signaling pathways revealed an overexpression of some of the iasmonate signaling pathway genes, which might trigger ectopic lignification in response to cell wall integrity disruptions. In summary, the structural plasticity of primary cell walls is proven, since a lignification process is possible in response to cellulose impoverishment.

关键词： Cellulose DCB dichlobenil ectopic lignin maize

Extracellular vesicles-coupled miRNAs from oviduct and uterus modulate signaling pathways related to lipid metabolism and bovine early embryo development

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journal of Animal Science and Biotechnology 2024年第4期15卷 1528-1549页

作者： Rosane Mazzarella Karina Canon‑Beltran Yulia N.Cajas Meriem Hamdi encina M.Gonzalez juliano C.da Silveira Claudia L.V.Leal D.Rizos Department of Animal Reproduction INIA-CSICMadridSpain Department of Biochemistry and Molecular Biology Veterinary FacultyComplutense University of Madrid(UCM)MadridSpain Department Agrarian Production Technical University of MadridUPMMadridSpain Departamento de Ciencias Biologicas Universidad Tecnica Particular de LojaUTPLLojaEcuador Department of Anatomy and Embryology FV-UCMMadridSpain Department of Veterinary Medicine FZEA-USPPirassunungaBrazil

Background Extracellular vesicles(EVs) present in oviductal(OF) and uterine fluid(UF) have been shown to enhance bovine embryo quality during in vitro culture by reducing lipid contents and modulating lipid metabolism-related genes(LMGs), while also influencing cell proliferation, suggesting their involvement on the regulation of different biological pathways. The regulation of signaling pathways related to cell differentiation, proliferation, and metabo-lism is crucial for early embryo development and can determine the success or failure of the pregnancy. Bioactive molecules within EVs in maternal reproductive fluids, such as micro RNAs(miRNAs), may contribute to this regulatory process as they modulate gene expression through post-transcriptional *** This study evaluated miRNA cargo in OF-EVs from the early luteal phase and UF-EVs from the mid-luteal phase, coinciding with embryo transit within oviduct and uterus in vivo, and its possible influence on LMGs and sign-aling pathways crucial for early embryo development. A total of 333 miRNAs were detected, with 11 exclusive to OF, 59 to UF, and 263 were common between both groups. From the 20 differentially expressed miRNAs, 19 up-regulated in UF-EVs(bta-miR-134, bta-miR-151-3p, bta-miR-155, bta-miR-188, bta-miR-181b, bta-miR-181d, bta-miR-224, bta-miR-23b-3p, bta-miR-24-3p, bta-miR-27a-3p, bta-miR-29a, bta-miR-324, bta-miR-326, bta-miR-345-3p, bta-miR-410, bta-miR-652, bta-miR-677, bta-miR-873 and bta-miR-708) and one(bta-miR-148b) in OF-EVs. These miRNAs were predicted to modulate several pathways such as Wnt, Hippo, MAPK, and lipid metabolism and degradation. Differ-ences in miRNAs found in OF-EVs from the early luteal phase and UF-EVs from mid-luteal phase may reflect differ-ent environments to meet the changing needs of the embryo. Additionally, miRNAs may be involved, particularly in the uterus, in the regulation of embryo lipid metabolism, immune system, and *** Our study su

关键词： Embryo-maternal interaction Epigenetic Exosomes Mammalian Preimplantation Reproductive fluids