The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Jay J. Thelen - One of the best experts on this subject based on the ideXlab platform.
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Large-scale proteome comparative analysis of developing Rhizomes of the ancient vascular plant Equisetum hyemale
Frontiers in Plant Science, 2012Co-Authors: Tiago Santana Balbuena, Fernanda Salvato, Ruifeng He, David R Gang, Jay J. ThelenAbstract:Horsetail (Equisetum hyemale) is a widespread vascular plant species, whose reproduction is mainly dependent on the growth and development of the Rhizomes. Due to its key evolutionary position, the identification of factors that could be involved in the existence of the rhizomatous trait may contribute to a better understanding of the role of this underground organ for the successful propagation of this and other plant species. In the present work, we characterized the proteome of E. hyemale Rhizomes using a GeLC-MS spectral-counting proteomics strategy. A total of 1,911 and 1,860 non-redundant proteins were identified in the Rhizomes apical tip and elongation zone, respectively. Rhizome-characteristic proteins were determined by comparisons of the developing Rhizome tissues to developing roots. A total of 87 proteins were found to be up-regulated in both horsetail Rhizome tissues in relation to developing roots. Hierarchical clustering indicated a vast dynamic range in the regulation of the 87 characteristic proteins and revealed, based on the regulation profile, the existence of nine major protein groups. Gene ontology analyses suggested an over-representation of the terms involved in macromolecular and protein biosynthetic processes, gene expression, and nucleotide and protein binding functions. Spatial difference analysis between the Rhizome apical tip and the elongation zone revealed that only eight proteins were up-regulated in the apical tip including RNA-binding proteins and an acyl carrier protein, as well as a KH domain protein and a T-complex subunit; while only seven proteins were up-regulated in the elongation zone including phosphomannomutase, galactomannan galactosyltransferase, endoglucanase 10 and 25, and mannose-1-phosphate guanyltransferase subunits alpha and beta. This is the first large-scale characterization of the proteome of a plant Rhizome. Implications of the findings were discussed in relation to other underground organs and related species.
Ole Pedersen - One of the best experts on this subject based on the ideXlab platform.
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leaf gas films of spartina anglica enhance Rhizome and root oxygen during tidal submergence
Plant Cell and Environment, 2011Co-Authors: Anders Winkel, Timothy D Colmer, Ole PedersenAbstract:Gas films on hydrophobic surfaces of leaves of some wetland plants can improve O2 and CO2 exchange when completely submerged during floods. Here we investigated the in situ aeration of Rhizomes of cordgrass (Spartina anglica) during natural tidal submergence, with focus on the role of leaf gas films on underwater gas exchange. Underwater net photosynthesis was also studied in controlled laboratory experiments. In field experiments, O2 microelectrodes were inserted into Rhizomes and pO2 measured throughout two tidal submergence events; one during daylight and one during night-time. Plants had leaf gas films intact or removed. Rhizome pO2 dropped significantly during complete submergence and most severely during night. Leaf gas films: (1) enhanced underwater photosynthesis and pO2 in Rhizomes remained above 10 kPa during submergence in light; and (2) facilitated O2 entry from the water into leaves so that Rhizome pO2 was about 5 kPa during darkness. This study is the first in situ demonstration of the beneficial effects of leaf gas films on internal aeration in a submerged wetland plant. Leaf gas films likely contribute to submergence tolerance of S. anglica and this feature is expected to also benefit other wetland plant species when submerged.
Cesar A N Catalan - One of the best experts on this subject based on the ideXlab platform.
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comparative study of chemical composition and antioxidant activity of fresh and dry Rhizomes of turmeric curcuma longa linn
Food and Chemical Toxicology, 2010Co-Authors: G Singh, I P S Kapoor, Pratibha Singh, Carola S De Heluani, Marina P De Lampasona, Cesar A N CatalanAbstract:Abstract The phytoconstituents of essential oil and ethanol oleoresin of fresh and dry Rhizomes of turmeric (Curcuma longa Linn.) were analyzed by GC–MS. The major constituents were aromatic-turmerone (24.4%), alpha-turmerone (20.5%) and beta-turmerone (11.1%) in fresh Rhizome and aromatic-turmerone (21.4%), alpha-santalene (7.2%) and aromatic-curcumene (6.6%) in dry Rhizome oil. Whereas, in oleoresins, the major components were alpha-turmerone (53.4%), beta-turmerone (18.1%) and aromatic-turmerone (6.2%) in fresh and aromatic-turmerone (9.6%), alpha-santalene (7.8%) and alpha-turmerone (6.5%) in dry Rhizome. Results showed that alpha-turmerone, a major component in fresh Rhizomes is only minor one in dry Rhizomes. Also, the content of beta-turmerone in dry Rhizomes is less than a half amount found in fresh Rhizomes. The antioxidant properties have been assessed by various lipid peroxidation assays as well as DPPH radical scavenging and metal chelating methods. The essential oil and ethanol oleoresin of fresh Rhizomes have higher antioxidant properties as compared dry ones.
Andre Kessler - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous analysis of tissue- and genotype-specific variation in Solidago altissima (Asteraceae) Rhizome terpenoids, and the polyacetylene dehydromatricaria ester
Chemoecology, 2010Co-Authors: Robert H. Johnson, Rayko Halitschke, Andre KesslerAbstract:Solidago altissima is a dominant perennial of old field succession in North America with the ability to form dense, almost monospecific stands; the plant is also considered an aggressive invasive throughout Europe and Japan. S. altissima ’s success is facilitated by large belowground Rhizome systems that allow clonal spread and possible allelopathic suppression of competitors. A diversity of polar and nonpolar terpenes and polyacetylenes have been described from S. altissima Rhizomes; however, there is little information documenting the concentration or distribution of these allelochemicals and how they relate to plant defense hypotheses. We thus developed a GC–MS method to simultaneously quantify Rhizome terpenes and polyacetylenes that spanned a range of polarities and confirmed the presence of 19 terpenoids in addition to the polyacetylene dehydromatricaria ester (DME). We, (1) determined relative concentrations and variability of mono-, sesqui-, neutral diterpenes, diterpene acids and DME within a central NY population; (2) compared accumulation of these compounds in differently developed Rhizome tissue; and (3) tested the alleopathic effect of DME at naturally occurring concentrations on germination and seedling growth of Asclepias syriaca , a common competitor of S. altissima . Overall, diterpene acids dominated the phytochemical profile of most genotypes (averaging 0.75% of fresh mass) with kolavenic acid being the single most abundant component. Monoterpene, sesquiterpene and acidic diterpene concentrations were all significantly greater in the actively elongating (current-year) Rhizomes compared to established Rhizomes and followed optimal defense theory predictions. Conversely, DME levels were lower in the current-year Rhizomes than in established Rhizomes. DME inhibited seed germination of A. syriaca in a dose-dependent manner. The tissue-specific accumulation of the different compounds may represent a biosynthetic and/or allocational strategy that limits the exposure of young-tissue to high concentrations of DME possibly limiting the cytotoxic effects of DME.
Tiago Santana Balbuena - One of the best experts on this subject based on the ideXlab platform.
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Large-scale proteome comparative analysis of developing Rhizomes of the ancient vascular plant Equisetum hyemale
Frontiers in Plant Science, 2012Co-Authors: Tiago Santana Balbuena, Fernanda Salvato, Ruifeng He, David R Gang, Jay J. ThelenAbstract:Horsetail (Equisetum hyemale) is a widespread vascular plant species, whose reproduction is mainly dependent on the growth and development of the Rhizomes. Due to its key evolutionary position, the identification of factors that could be involved in the existence of the rhizomatous trait may contribute to a better understanding of the role of this underground organ for the successful propagation of this and other plant species. In the present work, we characterized the proteome of E. hyemale Rhizomes using a GeLC-MS spectral-counting proteomics strategy. A total of 1,911 and 1,860 non-redundant proteins were identified in the Rhizomes apical tip and elongation zone, respectively. Rhizome-characteristic proteins were determined by comparisons of the developing Rhizome tissues to developing roots. A total of 87 proteins were found to be up-regulated in both horsetail Rhizome tissues in relation to developing roots. Hierarchical clustering indicated a vast dynamic range in the regulation of the 87 characteristic proteins and revealed, based on the regulation profile, the existence of nine major protein groups. Gene ontology analyses suggested an over-representation of the terms involved in macromolecular and protein biosynthetic processes, gene expression, and nucleotide and protein binding functions. Spatial difference analysis between the Rhizome apical tip and the elongation zone revealed that only eight proteins were up-regulated in the apical tip including RNA-binding proteins and an acyl carrier protein, as well as a KH domain protein and a T-complex subunit; while only seven proteins were up-regulated in the elongation zone including phosphomannomutase, galactomannan galactosyltransferase, endoglucanase 10 and 25, and mannose-1-phosphate guanyltransferase subunits alpha and beta. This is the first large-scale characterization of the proteome of a plant Rhizome. Implications of the findings were discussed in relation to other underground organs and related species.
