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Abies Grandis

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Rodney Croteau – One of the best experts on this subject based on the ideXlab platform.

Jörg Bohlmann – One of the best experts on this subject based on the ideXlab platform.

  • Novartis Foundation Symposium 223 – Insect-Plant Interactions and Induced Plant Defence – Diversity and variability of terpenoid defences in conifers: molecular genetics, biochemistry and evolution of the terpene synthase gene family in grand fir (Ab
    Novartis Foundation symposium, 2007
    Co-Authors: Jörg Bohlmann, Rodney Croteau
    Abstract:

    This review focuses on the molecular genetics, biochemistry and evolution of terpenoid synthases relevant to terpenoid defences in conifers. In grand fir (Abies Grandis) biosynthesis of terpenoids of the three classes of monoterpenes, sesquiterpenes and diterpenes is inducible by stem wounding at the level of gene activation and increase of enzyme activity of the respective terpene synthases. The monoterpene, sesquiterpene and diterpene synthases utilize prenyl diphosphates of appropriate size as substrates to generate the large diversity of carbon skeletons characteristic of the terpenoid resin of conifers. A large and diverse gene family of grand fir terpene synthases has been cloned and cDNAs are actively expressed in Escherichia coli for enzyme characterization. The monophyletic group of grand fir monoterpene, sesquiterpene and diterpene synthases represents both constitutively expressed and inducible genes encoding single product and multiple product enzymes. Several events of gene duplication and functional specialization of new synthases occurred during the evolution of terpenoid biosynthesis in grand fir, and gave rise to the enormous diversity and variability of this ancient and successful plant defence against herbivores and pathogens. The review concludes with a perspective of the biotechnological applications of terpenoid synthases for the genetic engineering of agricultural crops and forest trees.

  • cDNA cloning, characterization, and functional expression of four new monoterpene synthase members of the Tpsd gene family from grand fir (Abies Grandis)
    Archives of biochemistry and biophysics, 1999
    Co-Authors: Jörg Bohlmann, Sadanobu Katoh, Michael A. Phillips, Vasanthi Ramachandiran, Rodney Croteau
    Abstract:

    Abstract Grand fir (Abies Grandis) is a useful model system for studying the biochemistry, molecular genetics, and regulation of defensive oleoresin formation in conifers, a process involving both the constitutive accumulation of resin (pitch) in specialized secretory structures and the induced biosynthesis of monoterpenes and sesquiterpenes (turpentine) and diterpene resin acids (rosin) by nonspecialized cells at the site of injury. A similarity-based cloning strategy, employing primers designed to conserved regions of existing monoterpene synthases and anticipated to amplify a 1000-bp fragment, unexpectedly yielded a 300-bp fragment with sequence reminiscent of a terpenoid synthase. Utilization of this amplicon as a hybridization probe afforded four new, full-length cDNA species from a wounded fir stem cDNA library that appeared to encode four distinct monoterpene synthases. Expression in Escherichia coli, followed by enzyme assay with geranyl diphosphate (C10), farnesyl diphosphate (C15) and geranylgeranyl diphosphate (C20), and analysis of the terpene products by chiral phase gas chromatography and mass spectrometry confirmed that these sequences encoded four new monoterpene synthases, including (−)-camphene synthase, (−)-β-phellandrene synthase, terpinolene synthase, and an enzyme that produces both (−)-limonene and (−)-α-pinene. The deduced amino acid sequences indicated these enzymes to be 618 to 637 residues in length (71 to 73 kDa) and to be translated as preproteins bearing an amino-terminal plastid targeting sequence of 50–60 residues. cDNA truncation to delete the transit peptide allowed functional expression of the “pseudomature” forms of these enzymes, which exhibited no change in product outcome as a result of truncation. Sequence comparison revealed that these new monoterpene synthases from grand fir are members of the Tpsd gene subfamily and resemble sesquiterpene (C15) synthases and diterpene (C20) synthases from conifers more closely than mechanistically related monoterpene synthases from angiosperm species. The availability of a nearly complete set of constitutive and inducible monoterpene synthases from grand fir (now numbering seven) will allow molecular dissection of the resin-based defense response in this conifer species, and detailed study of structure–function relationships among this large and diverse family of catalysts, all of which exploit the same stereochemistry in the coupled isomerizationcyclization reaction.

  • diversity and variability of terpenoid defences in conifers molecular genetics biochemistry and evolution of the terpene synthase gene family in grand fir Abies Grandis
    Novartis Foundation symposium, 1999
    Co-Authors: Jörg Bohlmann, Rodney Croteau
    Abstract:

    This review focuses on the molecular genetics, biochemistry and evolution of terpenoid synthases relevant to terpenoid defences in conifers. In grand fir (Abies Grandis) biosynthesis of terpenoids of the three classes of monoterpenes, sesquiterpenes and diterpenes is inducible by stem wounding at the level of gene activation and increase of enzyme activity of the respective terpene synthases. The monoterpene, sesquiterpene and diterpene synthases utilize prenyl diphosphates of appropriate size as substrates to generate the large diversity of carbon skeletons characteristic of the terpenoid resin of conifers. A large and diverse gene family of grand fir terpene synthases has been cloned and cDNAs are actively expressed in Escherichia coli for enzyme characterization. The monophyletic group of grand fir monoterpene, sesquiterpene and diterpene synthases represents both constitutively expressed and inducible genes encoding single product and multiple product enzymes. Several events of gene duplication and functional specialization of new synthases occurred during the evolution of terpenoid biosynthesis in grand fir, and gave rise to the enormous diversity and variability of this ancient and successful plant defence against herbivores and pathogens. The review concludes with a perspective of the biotechnological applications of terpenoid synthases for the genetic engineering of agricultural crops and forest trees.

Nicole L. Lang – One of the best experts on this subject based on the ideXlab platform.

  • Tree invasion of a montane meadow complex: temporal trends, spatial patterns, and biotic interactions
    , 2014
    Co-Authors: Charles B. Halpern, Joseph A. Antos, Janine M. Rice, Ryan D. Haugo, Nicole L. Lang
    Abstract:

    Questions: Do spatial and temporal patterns of encroachment of Pinus contorta and Abies Grandis in a montane meadow suggest strong biotic controls on the invasion process? Location: Forest–meadow mosaic, 1350m a.s.l.

  • Tree invasion of a montane meadow complex: temporal trends, spatial patterns, and biotic interactions
    Journal of Vegetation Science, 2010
    Co-Authors: Charles B. Halpern, Joseph A. Antos, Janine M. Rice, Ryan D. Haugo, Nicole L. Lang
    Abstract:

    Questions: Do spatial and temporal patterns of encroachment of Pinus contorta and Abies Grandis in a montane meadow suggest strong biotic controls on the invasion process? Location: Forest–meadow mosaic, 1350 m a.s.l., Cascade Range, Oregon, US. Methods: We combined spatial point pattern analysis, population age structures, and a time-series of stem maps to quantify spatial and temporal patterns of conifer invasion over a 200-yr period in three plots totaling 4 ha. Results: Trees established during two broad, but distinct periods (late 1800s, then at much greater density in the mid-1900s). Recent invasion was not correlated with climatic variation. Abies Grandis dominated both periods; P. contorta established at lower density, peaking before A. Grandis. Spatially, older (� 90 yr) P. contorta were randomly distributed, but older A. Grandis were strongly clumped (0.2-20 m). Younger (o90 yr) stems were positively associated at small distances (both within and between species), but were spatially displaced from older A. Grandis, suggesting a temporal shift from facilitation to competition. Establishment during the 1800s resulted in widely scattered P. contorta and clumps of A. Grandis that placed most areas of meadow close to seed sources permitting more rapid invasion during the mid-1900s. Rapid conversion to forest occurred via colonization of larger meadow openings – first by shade-intolerant P. contorta, then by shade-tolerant A. Grandis – and by direct infilling of smaller openings by A. Grandis. Conclusions: In combination, spatial and temporal patterns of establishment suggest an invasion process shaped by biotic interactions, with facilitation promoting expansion of trees into meadows and competition influencing subsequent forest development. Once invasion is initiated, tree species with different life histories and functional traits can interact synergistically to promote rapid conversion of meadow to forest under a broad range of climatic conditions.

Charles B. Halpern – One of the best experts on this subject based on the ideXlab platform.

  • Tree invasion of a montane meadow complex: temporal trends, spatial patterns, and biotic interactions
    , 2014
    Co-Authors: Charles B. Halpern, Joseph A. Antos, Janine M. Rice, Ryan D. Haugo, Nicole L. Lang
    Abstract:

    Questions: Do spatial and temporal patterns of encroachment of Pinus contorta and Abies Grandis in a montane meadow suggest strong biotic controls on the invasion process? Location: Forest–meadow mosaic, 1350m a.s.l.

  • Tree invasion of a montane meadow complex: temporal trends, spatial patterns, and biotic interactions
    Journal of Vegetation Science, 2010
    Co-Authors: Charles B. Halpern, Joseph A. Antos, Janine M. Rice, Ryan D. Haugo, Nicole L. Lang
    Abstract:

    Questions: Do spatial and temporal patterns of encroachment of Pinus contorta and Abies Grandis in a montane meadow suggest strong biotic controls on the invasion process? Location: Forest–meadow mosaic, 1350 m a.s.l., Cascade Range, Oregon, US. Methods: We combined spatial point pattern analysis, population age structures, and a time-series of stem maps to quantify spatial and temporal patterns of conifer invasion over a 200-yr period in three plots totaling 4 ha. Results: Trees established during two broad, but distinct periods (late 1800s, then at much greater density in the mid-1900s). Recent invasion was not correlated with climatic variation. Abies Grandis dominated both periods; P. contorta established at lower density, peaking before A. Grandis. Spatially, older (� 90 yr) P. contorta were randomly distributed, but older A. Grandis were strongly clumped (0.2-20 m). Younger (o90 yr) stems were positively associated at small distances (both within and between species), but were spatially displaced from older A. Grandis, suggesting a temporal shift from facilitation to competition. Establishment during the 1800s resulted in widely scattered P. contorta and clumps of A. Grandis that placed most areas of meadow close to seed sources permitting more rapid invasion during the mid-1900s. Rapid conversion to forest occurred via colonization of larger meadow openings – first by shade-intolerant P. contorta, then by shade-tolerant A. Grandis – and by direct infilling of smaller openings by A. Grandis. Conclusions: In combination, spatial and temporal patterns of establishment suggest an invasion process shaped by biotic interactions, with facilitation promoting expansion of trees into meadows and competition influencing subsequent forest development. Once invasion is initiated, tree species with different life histories and functional traits can interact synergistically to promote rapid conversion of meadow to forest under a broad range of climatic conditions.

Sadanobu Katoh – One of the best experts on this subject based on the ideXlab platform.

  • Altering product outcome in Abies Grandis (−)-limonene synthase and (−)-limonene/(−)-α-pinene synthase by domain swapping and directed mutagenesis ☆
    Archives of biochemistry and biophysics, 2004
    Co-Authors: Sadanobu Katoh, David Hyatt, Rodney Croteau
    Abstract:

    Abstract (−)-(4 S )-limonene synthase (LS) and (−)-(4 S )-limonene/(−)-(1 S , 5 S )-α-pinene synthase (LPS) from grand fir ( Abies Grandis ) exhibit nearly 91% sequence identity (93% similarity) at the amino acid level, yet produce very different mixtures of monoterpene olefins. To elucidate critical amino acids involved in determining monoterpene product distribution, a combination of domain swapping and reciprocal site-directed mutagenesis was carried out between these two enzymes. Exchange of the predicted helix D through F region in LS gave rise to an LPS-like product outcome, whereas reciprocal substitutions of four amino acids in LPS (two in the predicted helix D and two in the predicted helix F) altered the product distribution to that intermediate between LS and LPS, and resulted in a 5-fold increase in relative velocity. These results, in conjunction with modeling of the two enzymes, suggest that amino acids in the predicted D through F helix regions are critical for product determination.

  • altering product outcome in Abies Grandis limonene synthase and limonene α pinene synthase by domain swapping and directed mutagenesis
    Archives of Biochemistry and Biophysics, 2004
    Co-Authors: Sadanobu Katoh, David Hyatt, Rodney Croteau
    Abstract:

    Abstract (−)-(4 S )-limonene synthase (LS) and (−)-(4 S )-limonene/(−)-(1 S , 5 S )-α-pinene synthase (LPS) from grand fir ( Abies Grandis ) exhibit nearly 91% sequence identity (93% similarity) at the amino acid level, yet produce very different mixtures of monoterpene olefins. To elucidate critical amino acids involved in determining monoterpene product distribution, a combination of domain swapping and reciprocal site-directed mutamutagenesis was carried out between these two enzymes. Exchange of the predicted helix D through F region in LS gave rise to an LPS-like product outcome, whereas reciprocal substitutions of four amino acids in LPS (two in the predicted helix D and two in the predicted helix F) altered the product distribution to that intermediate between LS and LPS, and resulted in a 5-fold increase in relative velocity. These results, in conjunction with modeling of the two enzymes, suggest that amino acids in the predicted D through F helix regions are critical for product determination.

  • cDNA cloning, characterization, and functional expression of four new monoterpene synthase members of the Tpsd gene family from grand fir (Abies Grandis)
    Archives of biochemistry and biophysics, 1999
    Co-Authors: Jörg Bohlmann, Sadanobu Katoh, Michael A. Phillips, Vasanthi Ramachandiran, Rodney Croteau
    Abstract:

    Abstract Grand fir (Abies Grandis) is a useful model system for studying the biochemistry, molecular genetics, and regulation of defensive oleoresin formation in conifers, a process involving both the constitutive accumulation of resin (pitch) in specialized secretory structures and the induced biosynthesis of monoterpenes and sesquiterpenes (turpentine) and diterpene resin acids (rosin) by nonspecialized cells at the site of injury. A similarity-based cloning strategy, employing primers designed to conserved regions of existing monoterpene synthases and anticipated to amplify a 1000-bp fragment, unexpectedly yielded a 300-bp fragment with sequence reminiscent of a terpenoid synthase. Utilization of this amplicon as a hybridization probe afforded four new, full-length cDNA species from a wounded fir stem cDNA library that appeared to encode four distinct monoterpene synthases. Expression in Escherichia coli, followed by enzyme assay with geranyl diphosphate (C10), farnesyl diphosphate (C15) and geranylgeranyl diphosphate (C20), and analysis of the terpene products by chiral phase gas chromatography and mass spectrometry confirmed that these sequences encoded four new monoterpene synthases, including (−)-camphene synthase, (−)-β-phellandrene synthase, terpinolene synthase, and an enzyme that produces both (−)-limonene and (−)-α-pinene. The deduced amino acid sequences indicated these enzymes to be 618 to 637 residues in length (71 to 73 kDa) and to be translated as preproteins bearing an amino-terminal plastid targeting sequence of 50–60 residues. cDNA truncation to delete the transit peptide allowed functional expression of the “pseudomature” forms of these enzymes, which exhibited no change in product outcome as a result of truncation. Sequence comparison revealed that these new monoterpene synthases from grand fir are members of the Tpsd gene subfamily and resemble sesquiterpene (C15) synthases and diterpene (C20) synthases from conifers more closely than mechanistically related monoterpene synthases from angiosperm species. The availability of a nearly complete set of constitutive and inducible monoterpene synthases from grand fir (now numbering seven) will allow molecular dissection of the resin-based defense response in this conifer species, and detailed study of structure–function relationships among this large and diverse family of catalysts, all of which exploit the same stereochemistry in the coupled isomerization–cyclization reaction.