The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
Joerg Bohlmann - One of the best experts on this subject based on the ideXlab platform.
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plasticity and evolution of 3 Carene synthase and sabinene synthase functions of a sitka spruce monoterpene synthase gene family associated with weevil resistance
Journal of Biological Chemistry, 2014Co-Authors: Christopher R Roach, Dawn E Hall, Philipp Zerbe, Joerg BohlmannAbstract:The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce against white pine weevil, a major North American forest insect pest of pine and spruce. High and low levels of (+)-3-Carene in, respectively, resistant and susceptible Sitka spruce genotypes are due to variation of (+)-3-Carene synthase gene copy number, transcript and protein expression levels, enzyme product profiles, and enzyme catalytic efficiency. A family of multiproduct (+)-3-Carene synthase-like genes of Sitka spruce include the three (+)-3-Carene synthases, PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and the (−)-sabinene synthase PsTPS-sab. Of these, PsTPS-3car2 is responsible for the relatively higher levels of (+)-3-Carene in weevil-resistant trees. Here, we identified features of the PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and PsTPS-sab proteins that determine different product profiles. A series of domain swap and site-directed mutations, supported by structural comparisons, identified the amino acid in position 596 as critical for product profiles dominated by (+)-3-Carene in PsTPS-3car1, PsTPS-3car2, and PsTPS-3car3, or (−)-sabinene in PsTPS-sab. A leucine in this position promotes formation of (+)-3-Carene, whereas phenylalanine promotes (−)-sabinene. Homology modeling predicts that position 596 directs product profiles through differential stabilization of the reaction intermediate. Kinetic analysis revealed position 596 also plays a role in catalytic efficiency. Mutations of position 596 with different side chain properties resulted in a series of enzymes with different product profiles, further highlighting the inherent plasticity and potential for evolution of alternative product profiles of these monoterpene synthases of conifer defense against insects.
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Plasticity and evolution of (+)-3-Carene synthase and (-)-sabinene synthase functions of a sitka spruce monoterpene synthase gene family associated with weevil resistance.
Journal of Biological Chemistry, 2014Co-Authors: Christopher R Roach, Dawn E Hall, Philipp Zerbe, Joerg BohlmannAbstract:The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce against white pine weevil, a major North American forest insect pest of pine and spruce. High and low levels of (+)-3-Carene in, respectively, resistant and susceptible Sitka spruce genotypes are due to variation of (+)-3-Carene synthase gene copy number, transcript and protein expression levels, enzyme product profiles, and enzyme catalytic efficiency. A family of multiproduct (+)-3-Carene synthase-like genes of Sitka spruce include the three (+)-3-Carene synthases, PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and the (−)-sabinene synthase PsTPS-sab. Of these, PsTPS-3car2 is responsible for the relatively higher levels of (+)-3-Carene in weevil-resistant trees. Here, we identified features of the PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and PsTPS-sab proteins that determine different product profiles. A series of domain swap and site-directed mutations, supported by structural comparisons, identified the amino acid in position 596 as critical for product profiles dominated by (+)-3-Carene in PsTPS-3car1, PsTPS-3car2, and PsTPS-3car3, or (−)-sabinene in PsTPS-sab. A leucine in this position promotes formation of (+)-3-Carene, whereas phenylalanine promotes (−)-sabinene. Homology modeling predicts that position 596 directs product profiles through differential stabilization of the reaction intermediate. Kinetic analysis revealed position 596 also plays a role in catalytic efficiency. Mutations of position 596 with different side chain properties resulted in a series of enzymes with different product profiles, further highlighting the inherent plasticity and potential for evolution of alternative product profiles of these monoterpene synthases of conifer defense against insects.
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Biomarkers and gene copy number variation for terpenoid traits associated with insect resistance in Sitka spruce: An integrated genomic, proteomic, and biochemical analysis of (+)-3-Carene biosynthesis
BMC Proceedings, 2011Co-Authors: Joerg Bohlmann, Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H BorchersAbstract:Conifers have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. The large diversity of terpenoid metabolites is determined by the size and composition of the terpene synthase (TPS) gene family, and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (82-95% amino acid sequence identity) (+)-3-Carene synthase (PsTPS-3car) genes. Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) which is expressed in both genotypes, one gene (PsTPS-3car2) expressed only in resistant trees, and one gene (PsTPS-3car3) expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring substantiated this pattern of differential expression of members of the PsTPS-3car family on the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3as a factor for the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by PsTPS-3car gene copy number variation, variation of gene and protein expression, and variation of catalytic efficiencies.
Dawn E Hall - One of the best experts on this subject based on the ideXlab platform.
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plasticity and evolution of 3 Carene synthase and sabinene synthase functions of a sitka spruce monoterpene synthase gene family associated with weevil resistance
Journal of Biological Chemistry, 2014Co-Authors: Christopher R Roach, Dawn E Hall, Philipp Zerbe, Joerg BohlmannAbstract:The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce against white pine weevil, a major North American forest insect pest of pine and spruce. High and low levels of (+)-3-Carene in, respectively, resistant and susceptible Sitka spruce genotypes are due to variation of (+)-3-Carene synthase gene copy number, transcript and protein expression levels, enzyme product profiles, and enzyme catalytic efficiency. A family of multiproduct (+)-3-Carene synthase-like genes of Sitka spruce include the three (+)-3-Carene synthases, PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and the (−)-sabinene synthase PsTPS-sab. Of these, PsTPS-3car2 is responsible for the relatively higher levels of (+)-3-Carene in weevil-resistant trees. Here, we identified features of the PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and PsTPS-sab proteins that determine different product profiles. A series of domain swap and site-directed mutations, supported by structural comparisons, identified the amino acid in position 596 as critical for product profiles dominated by (+)-3-Carene in PsTPS-3car1, PsTPS-3car2, and PsTPS-3car3, or (−)-sabinene in PsTPS-sab. A leucine in this position promotes formation of (+)-3-Carene, whereas phenylalanine promotes (−)-sabinene. Homology modeling predicts that position 596 directs product profiles through differential stabilization of the reaction intermediate. Kinetic analysis revealed position 596 also plays a role in catalytic efficiency. Mutations of position 596 with different side chain properties resulted in a series of enzymes with different product profiles, further highlighting the inherent plasticity and potential for evolution of alternative product profiles of these monoterpene synthases of conifer defense against insects.
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Plasticity and evolution of (+)-3-Carene synthase and (-)-sabinene synthase functions of a sitka spruce monoterpene synthase gene family associated with weevil resistance.
Journal of Biological Chemistry, 2014Co-Authors: Christopher R Roach, Dawn E Hall, Philipp Zerbe, Joerg BohlmannAbstract:The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce against white pine weevil, a major North American forest insect pest of pine and spruce. High and low levels of (+)-3-Carene in, respectively, resistant and susceptible Sitka spruce genotypes are due to variation of (+)-3-Carene synthase gene copy number, transcript and protein expression levels, enzyme product profiles, and enzyme catalytic efficiency. A family of multiproduct (+)-3-Carene synthase-like genes of Sitka spruce include the three (+)-3-Carene synthases, PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and the (−)-sabinene synthase PsTPS-sab. Of these, PsTPS-3car2 is responsible for the relatively higher levels of (+)-3-Carene in weevil-resistant trees. Here, we identified features of the PsTPS-3car1, PsTPS-3car2, PsTPS-3car3, and PsTPS-sab proteins that determine different product profiles. A series of domain swap and site-directed mutations, supported by structural comparisons, identified the amino acid in position 596 as critical for product profiles dominated by (+)-3-Carene in PsTPS-3car1, PsTPS-3car2, and PsTPS-3car3, or (−)-sabinene in PsTPS-sab. A leucine in this position promotes formation of (+)-3-Carene, whereas phenylalanine promotes (−)-sabinene. Homology modeling predicts that position 596 directs product profiles through differential stabilization of the reaction intermediate. Kinetic analysis revealed position 596 also plays a role in catalytic efficiency. Mutations of position 596 with different side chain properties resulted in a series of enzymes with different product profiles, further highlighting the inherent plasticity and potential for evolution of alternative product profiles of these monoterpene synthases of conifer defense against insects.
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Biomarkers and gene copy number variation for terpenoid traits associated with insect resistance in Sitka spruce: An integrated genomic, proteomic, and biochemical analysis of (+)-3-Carene biosynthesis
BMC Proceedings, 2011Co-Authors: Joerg Bohlmann, Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H BorchersAbstract:Conifers have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. The large diversity of terpenoid metabolites is determined by the size and composition of the terpene synthase (TPS) gene family, and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (82-95% amino acid sequence identity) (+)-3-Carene synthase (PsTPS-3car) genes. Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) which is expressed in both genotypes, one gene (PsTPS-3car2) expressed only in resistant trees, and one gene (PsTPS-3car3) expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring substantiated this pattern of differential expression of members of the PsTPS-3car family on the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3as a factor for the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by PsTPS-3car gene copy number variation, variation of gene and protein expression, and variation of catalytic efficiencies.
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an integrated genomic proteomic and biochemical analysis of 3 Carene biosynthesis in sitka spruce picea sitchensis genotypes that are resistant or susceptible to white pine weevil
Plant Journal, 2011Co-Authors: Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H Borchers, Jorg BohlmannAbstract:Conifers are extremely long-lived plants that have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. In these species, terpenoid diversity is determined by the size and composition of the terpene synthase (TPS) gene family and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (+)-3-Carene synthase (PsTPS-3car) genes (82-95% amino acid sequence identity). Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) that is expressed in both genotypes, one gene (PsTPS-3car2) that is expressed only in resistant trees, and one gene (PsTPS-3car3) that is expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring confirmed this pattern of differential expression of members of the PsTPS-3car family at the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3 as a factor contributing to the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by copy number variation of PsTPS-3car genes, variation of gene and protein expression, and variation in catalytic efficiencies.
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An integrated genomic, proteomic and biochemical analysis of (+)-3-Carene biosynthesis in Sitka spruce (Picea sitchensis) genotypes that are resistant or susceptible to white pine weevil.
The Plant journal : for cell and molecular biology, 2011Co-Authors: Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H Borchers, Jorg BohlmannAbstract:Conifers are extremely long-lived plants that have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. In these species, terpenoid diversity is determined by the size and composition of the terpene synthase (TPS) gene family and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (+)-3-Carene synthase (PsTPS-3car) genes (82-95% amino acid sequence identity). Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) that is expressed in both genotypes, one gene (PsTPS-3car2) that is expressed only in resistant trees, and one gene (PsTPS-3car3) that is expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring confirmed this pattern of differential expression of members of the PsTPS-3car family at the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3 as a factor contributing to the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by copy number variation of PsTPS-3car genes, variation of gene and protein expression, and variation in catalytic efficiencies.
Åke Ryrfeldt - One of the best experts on this subject based on the ideXlab platform.
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Increased airway responsiveness of a common fragrance component, 3-Carene, after skin sensitisation—a study in isolated guinea pig lungs
Toxicology letters, 2003Co-Authors: Lena Låstbom, Anders Boman, Per Camner, S. Johnsson, Åke RyrfeldtAbstract:Lungs from skin-sensitised and non-sensitised guinea pigs were exposed via the airways to 3-Carene (1900 mg/m 3 ) and perfused with buffer containing either autologous plasma or lymphocytes. The experiments were performed in order to investigate the importance of blood components for the increased lung responsiveness seen in skin-sensitised animals. A reduction in lung function was noted in all lungs during 3-Carene exposure. There was no difference in the 3-Carene response between lungs from skin-sensitised animals versus lungs from non-sensitised animals when the perfusion buffer contained lymphocytes. However, when plasma diluted with buffer was used as perfusion medium, there was a significant enhancement in the response in lungs from sensitised versus lungs from non-sensitised animals. This implies that skin sensitisation increases lung responses to inhaled 3-Carene and those components in plasma, and not the lymphocyte fraction, contributes to the observed increased lung responsiveness.
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increased airway responsiveness of a common fragrance component 3 Carene after skin sensitisation a study in isolated guinea pig lungs
Toxicology Letters, 2003Co-Authors: Lena Låstbom, Anders Boman, Per Camner, S. Johnsson, Åke RyrfeldtAbstract:Lungs from skin-sensitised and non-sensitised guinea pigs were exposed via the airways to 3-Carene (1900 mg/m 3 ) and perfused with buffer containing either autologous plasma or lymphocytes. The experiments were performed in order to investigate the importance of blood components for the increased lung responsiveness seen in skin-sensitised animals. A reduction in lung function was noted in all lungs during 3-Carene exposure. There was no difference in the 3-Carene response between lungs from skin-sensitised animals versus lungs from non-sensitised animals when the perfusion buffer contained lymphocytes. However, when plasma diluted with buffer was used as perfusion medium, there was a significant enhancement in the response in lungs from sensitised versus lungs from non-sensitised animals. This implies that skin sensitisation increases lung responses to inhaled 3-Carene and those components in plasma, and not the lymphocyte fraction, contributes to the observed increased lung responsiveness.
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Increased airway responsiveness after skin sensitisation to 3-Carene, studied in isolated guinea pig lungs.
Toxicology, 2000Co-Authors: Lena Låstbom, Anders Boman, Per Camner, Åke RyrfeldtAbstract:Inhalation of 3-Carene has been shown to induce bronchoconstriction in concentrations not far from the threshold limit value. In this study, one group of guinea-pigs were sensitised by dermal exposure to 3-Carene according to the modified Cumulative Contact Enhancement Test protocol and another group of animals was used as controls. Lungs from the skin-sensitised and control guinea-pigs were perfused with diluted autologous blood (13 ml blood/87 ml buffer) and exposed to 3-Carene at an air concentration of 3000 mg/m3. In both groups there was a reduction in compliance and conductance but this reduction was significantly (P
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increased airway responsiveness after skin sensitisation to 3 Carene studied in isolated guinea pig lungs
Toxicology, 2000Co-Authors: Lena Låstbom, Anders Boman, Per Camner, Åke RyrfeldtAbstract:Inhalation of 3-Carene has been shown to induce bronchoconstriction in concentrations not far from the threshold limit value. In this study, one group of guinea-pigs were sensitised by dermal exposure to 3-Carene according to the modified Cumulative Contact Enhancement Test protocol and another group of animals was used as controls. Lungs from the skin-sensitised and control guinea-pigs were perfused with diluted autologous blood (13 ml blood/87 ml buffer) and exposed to 3-Carene at an air concentration of 3000 mg/m3. In both groups there was a reduction in compliance and conductance but this reduction was significantly (P<0.05) more pronounced (2.5–3 times) in lungs obtained from sensitised animals than from control animals. In a previous study with similar design, but with plain buffer instead of diluted autologous blood as perfusate, we found no statistically significant difference in lung bronchoconstriction. Thus, it is concluded that skin sensitisation can increase lung reactivity to 3-Carene and that important mediators of this effect seem to be present in the blood.
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Does airway responsiveness increase after skin sensitisation to 3-Carene : a study in isolated guinea pig lungs
Toxicology, 1998Co-Authors: Lena Låstbom, Anders Boman, Per Camner, Åke RyrfeldtAbstract:Guinea pigs were sensitised by dermal exposure to 3-Carene according to the modified cumulative contact enhancement test (CCET) protocol. Lungs from sensitised and non-sensitised animals were then perfused with buffer and exposed for a period of 10 min to two different air concentrations of 3-Carene, 600 and 3000 mg/m3. 3-Carene caused a statistically significant bronchoconstriction even at the relatively low concentration of 600 mg/m3 and the constriction was dose dependent. 600 mg/m3 of 3-Carene caused a reduction of 19% in conductance capacity and 16% in compliance capacity. 3000 mg/m3 of 3-Carene decreased lung compliance and conductance by 43 and 31%, respectively. The lungs from sensitised animals tended to show a greater response than lungs obtained from control animals. The lower concentration of 3-Carene is close to and may even be below, occupational limit values in Sweden, Germany and USA.
Lena Låstbom - One of the best experts on this subject based on the ideXlab platform.
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Increased airway responsiveness of a common fragrance component, 3-Carene, after skin sensitisation—a study in isolated guinea pig lungs
Toxicology letters, 2003Co-Authors: Lena Låstbom, Anders Boman, Per Camner, S. Johnsson, Åke RyrfeldtAbstract:Lungs from skin-sensitised and non-sensitised guinea pigs were exposed via the airways to 3-Carene (1900 mg/m 3 ) and perfused with buffer containing either autologous plasma or lymphocytes. The experiments were performed in order to investigate the importance of blood components for the increased lung responsiveness seen in skin-sensitised animals. A reduction in lung function was noted in all lungs during 3-Carene exposure. There was no difference in the 3-Carene response between lungs from skin-sensitised animals versus lungs from non-sensitised animals when the perfusion buffer contained lymphocytes. However, when plasma diluted with buffer was used as perfusion medium, there was a significant enhancement in the response in lungs from sensitised versus lungs from non-sensitised animals. This implies that skin sensitisation increases lung responses to inhaled 3-Carene and those components in plasma, and not the lymphocyte fraction, contributes to the observed increased lung responsiveness.
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increased airway responsiveness of a common fragrance component 3 Carene after skin sensitisation a study in isolated guinea pig lungs
Toxicology Letters, 2003Co-Authors: Lena Låstbom, Anders Boman, Per Camner, S. Johnsson, Åke RyrfeldtAbstract:Lungs from skin-sensitised and non-sensitised guinea pigs were exposed via the airways to 3-Carene (1900 mg/m 3 ) and perfused with buffer containing either autologous plasma or lymphocytes. The experiments were performed in order to investigate the importance of blood components for the increased lung responsiveness seen in skin-sensitised animals. A reduction in lung function was noted in all lungs during 3-Carene exposure. There was no difference in the 3-Carene response between lungs from skin-sensitised animals versus lungs from non-sensitised animals when the perfusion buffer contained lymphocytes. However, when plasma diluted with buffer was used as perfusion medium, there was a significant enhancement in the response in lungs from sensitised versus lungs from non-sensitised animals. This implies that skin sensitisation increases lung responses to inhaled 3-Carene and those components in plasma, and not the lymphocyte fraction, contributes to the observed increased lung responsiveness.
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Increased airway responsiveness after skin sensitisation to 3-Carene, studied in isolated guinea pig lungs.
Toxicology, 2000Co-Authors: Lena Låstbom, Anders Boman, Per Camner, Åke RyrfeldtAbstract:Inhalation of 3-Carene has been shown to induce bronchoconstriction in concentrations not far from the threshold limit value. In this study, one group of guinea-pigs were sensitised by dermal exposure to 3-Carene according to the modified Cumulative Contact Enhancement Test protocol and another group of animals was used as controls. Lungs from the skin-sensitised and control guinea-pigs were perfused with diluted autologous blood (13 ml blood/87 ml buffer) and exposed to 3-Carene at an air concentration of 3000 mg/m3. In both groups there was a reduction in compliance and conductance but this reduction was significantly (P
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increased airway responsiveness after skin sensitisation to 3 Carene studied in isolated guinea pig lungs
Toxicology, 2000Co-Authors: Lena Låstbom, Anders Boman, Per Camner, Åke RyrfeldtAbstract:Inhalation of 3-Carene has been shown to induce bronchoconstriction in concentrations not far from the threshold limit value. In this study, one group of guinea-pigs were sensitised by dermal exposure to 3-Carene according to the modified Cumulative Contact Enhancement Test protocol and another group of animals was used as controls. Lungs from the skin-sensitised and control guinea-pigs were perfused with diluted autologous blood (13 ml blood/87 ml buffer) and exposed to 3-Carene at an air concentration of 3000 mg/m3. In both groups there was a reduction in compliance and conductance but this reduction was significantly (P<0.05) more pronounced (2.5–3 times) in lungs obtained from sensitised animals than from control animals. In a previous study with similar design, but with plain buffer instead of diluted autologous blood as perfusate, we found no statistically significant difference in lung bronchoconstriction. Thus, it is concluded that skin sensitisation can increase lung reactivity to 3-Carene and that important mediators of this effect seem to be present in the blood.
-
Does airway responsiveness increase after skin sensitisation to 3-Carene : a study in isolated guinea pig lungs
Toxicology, 1998Co-Authors: Lena Låstbom, Anders Boman, Per Camner, Åke RyrfeldtAbstract:Guinea pigs were sensitised by dermal exposure to 3-Carene according to the modified cumulative contact enhancement test (CCET) protocol. Lungs from sensitised and non-sensitised animals were then perfused with buffer and exposed for a period of 10 min to two different air concentrations of 3-Carene, 600 and 3000 mg/m3. 3-Carene caused a statistically significant bronchoconstriction even at the relatively low concentration of 600 mg/m3 and the constriction was dose dependent. 600 mg/m3 of 3-Carene caused a reduction of 19% in conductance capacity and 16% in compliance capacity. 3000 mg/m3 of 3-Carene decreased lung compliance and conductance by 43 and 31%, respectively. The lungs from sensitised animals tended to show a greater response than lungs obtained from control animals. The lower concentration of 3-Carene is close to and may even be below, occupational limit values in Sweden, Germany and USA.
Christoph H Borchers - One of the best experts on this subject based on the ideXlab platform.
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Biomarkers and gene copy number variation for terpenoid traits associated with insect resistance in Sitka spruce: An integrated genomic, proteomic, and biochemical analysis of (+)-3-Carene biosynthesis
BMC Proceedings, 2011Co-Authors: Joerg Bohlmann, Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H BorchersAbstract:Conifers have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. The large diversity of terpenoid metabolites is determined by the size and composition of the terpene synthase (TPS) gene family, and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (82-95% amino acid sequence identity) (+)-3-Carene synthase (PsTPS-3car) genes. Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) which is expressed in both genotypes, one gene (PsTPS-3car2) expressed only in resistant trees, and one gene (PsTPS-3car3) expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring substantiated this pattern of differential expression of members of the PsTPS-3car family on the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3as a factor for the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by PsTPS-3car gene copy number variation, variation of gene and protein expression, and variation of catalytic efficiencies.
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an integrated genomic proteomic and biochemical analysis of 3 Carene biosynthesis in sitka spruce picea sitchensis genotypes that are resistant or susceptible to white pine weevil
Plant Journal, 2011Co-Authors: Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H Borchers, Jorg BohlmannAbstract:Conifers are extremely long-lived plants that have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. In these species, terpenoid diversity is determined by the size and composition of the terpene synthase (TPS) gene family and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (+)-3-Carene synthase (PsTPS-3car) genes (82-95% amino acid sequence identity). Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) that is expressed in both genotypes, one gene (PsTPS-3car2) that is expressed only in resistant trees, and one gene (PsTPS-3car3) that is expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring confirmed this pattern of differential expression of members of the PsTPS-3car family at the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3 as a factor contributing to the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by copy number variation of PsTPS-3car genes, variation of gene and protein expression, and variation in catalytic efficiencies.
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An integrated genomic, proteomic and biochemical analysis of (+)-3-Carene biosynthesis in Sitka spruce (Picea sitchensis) genotypes that are resistant or susceptible to white pine weevil.
The Plant journal : for cell and molecular biology, 2011Co-Authors: Dawn E Hall, Jeanne A Robert, Christopher I Keeling, Dominik Domanski, Alfonso Lara Quesada, Sharon Jancsik, Michael A Kuzyk, Britta Hamberger, Christoph H Borchers, Jorg BohlmannAbstract:Conifers are extremely long-lived plants that have evolved complex chemical defenses in the form of oleoresin terpenoids to resist attack from pathogens and herbivores. In these species, terpenoid diversity is determined by the size and composition of the terpene synthase (TPS) gene family and the single- and multi-product profiles of these enzymes. The monoterpene (+)-3-Carene is associated with resistance of Sitka spruce (Picea sitchensis) to white pine weevil (Pissodes strobi). We used a combined genomic, proteomic and biochemical approach to analyze the (+)-3-Carene phenotype in two contrasting Sitka spruce genotypes. Resistant trees produced significantly higher levels of (+)-3-Carene than susceptible trees, in which only trace amounts were detected. Biosynthesis of (+)-3-Carene is controlled, at the genome level, by a small family of closely related (+)-3-Carene synthase (PsTPS-3car) genes (82-95% amino acid sequence identity). Transcript profiling identified one PsTPS-3car gene (PsTPS-3car1) that is expressed in both genotypes, one gene (PsTPS-3car2) that is expressed only in resistant trees, and one gene (PsTPS-3car3) that is expressed only in susceptible trees. The PsTPS-3car2 gene was not detected in genomic DNA of susceptible trees. Target-specific selected reaction monitoring confirmed this pattern of differential expression of members of the PsTPS-3car family at the proteome level. Kinetic characterization of the recombinant PsTPS-3car enzymes identified differences in the activities of PsTPS-3car2 and PsTPS-3car3 as a factor contributing to the different (+)-3-Carene profiles of resistant and susceptible trees. In conclusion, variation of the (+)-3-Carene phenotype is controlled by copy number variation of PsTPS-3car genes, variation of gene and protein expression, and variation in catalytic efficiencies.
