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Wendell L. Roelofs - One of the best experts on this subject based on the ideXlab platform.
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regulation of pheromone biosynthesis by a brain hormone in two moth species neuroendocrine regulation pheromone biosynthesis fatty acid synthesis Argyrotaenia velutinana trichoplusia ni
2016Co-Authors: Juliet D Tang, Russell A. Jurenka, Ralph E Charlton, Walter A Wolf, P Larry, Leam Sreng, Wendell L. RoelofsAbstract:Experiments were performed to characterize the action of a brain hormone on pheromone biosynthesis in female redbanded leafroller and cabbage looper moths. Results showed that the two species differed in their respective control mechanisms. In the cabbage looper, pheromone titer from decapitated females that received either saline or brain extract injections was not significantly different from control females, suggesting that pheromone biosynthesis was not dependent on the presence of the brain hormone. In contrast, with redbanded leafroller females, studies using radiolabeled acetate incorpo- ration as well as incorporation of deuterium-labeled hexadec- anoic acid showed that (i) the brain hormone was required for pheromone biosynthesis, (ii) the brain hormone regulated pher- omone biosynthesis by activating synthesis of octadecanoyl and hexadecanoyl intermediates, and (iii) the brain hormone did not control other enzymes in the pathway. Regulation of fatty acid synthetase was unlikely since assays of the enzyme from decap- itated and normal females showed no differences in the amount or distribution of the 18- and 16-carbon acyl end products. These results in conjunction with those from organ cultures of the pheromone gland suggest that the brain hormone acts by increasing the substrate supply for fatty acid synthesis.
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Regulation of pheromone biosynthesis by a brain hormone in two moth species (neuroendocrine regulation/pheromone biosynthesis/fatty acid synthesis/Argyrotaenia velutinana/Trichoplusia ni)
2016Co-Authors: Juliet D Tang, Russell A. Jurenka, Ralph E Charlton, Walter A Wolf, P Larry, Leam Sreng, Wendell L. RoelofsAbstract:Experiments were performed to characterize the action of a brain hormone on pheromone biosynthesis in female redbanded leafroller and cabbage looper moths. Results showed that the two species differed in their respective control mechanisms. In the cabbage looper, pheromone titer from decapitated females that received either saline or brain extract injections was not significantly different from control females, suggesting that pheromone biosynthesis was not dependent on the presence of the brain hormone. In contrast, with redbanded leafroller females, studies using radiolabeled acetate incorpo- ration as well as incorporation of deuterium-labeled hexadec- anoic acid showed that (i) the brain hormone was required for pheromone biosynthesis, (ii) the brain hormone regulated pher- omone biosynthesis by activating synthesis of octadecanoyl and hexadecanoyl intermediates, and (iii) the brain hormone did not control other enzymes in the pathway. Regulation of fatty acid synthetase was unlikely since assays of the enzyme from decap- itated and normal females showed no differences in the amount or distribution of the 18- and 16-carbon acyl end products. These results in conjunction with those from organ cultures of the pheromone gland suggest that the brain hormone acts by increasing the substrate supply for fatty acid synthesis.
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Characterization of Z/E11- and Z9-desaturases from the obliquebanded leafroller moth, Choristoneura rosaceana.
Journal of insect science (Online), 2002Co-Authors: Marion O'connor, Wendell L. RoelofsAbstract:A (triangle up) 11-desaturase gene was cloned from the sex pheromone gland of the obliquebanded leafroller moth, Choristoneura rosaceana. The desaturase cDNA sequence spans 1300 nucleotides with an open reading frame encoding a 335 amino-acid protein, which has 81% identity to a Z/E11-desaturase of the redbanded leafroller moth, Argyrotaenia velutinana. A functional assay with a pYES2 yeast expression system demonstrated that the (triangle up) 11-desaturase exhibits unusual substrate and stereospecificities in producing a Z/E11 mixture (7:1) of only C14 acids. A metabolic Z9-desaturase also was cloned from fat body of this species, and proved to be in the class that produces more Z9-16:Acid than Z9-18:Acid.
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Characterization of Z/E11- and Z9-desaturases from the obliquebanded leafroller moth, Choristoneura rosaceana
Journal of Insect Science, 2002Co-Authors: Marion O'connor, Wendell L. RoelofsAbstract:Abstract A ▵11-desaturase gene was cloned from the sex pheromone gland of the obliquebanded leafroller moth, Choristoneura rosaceana. The desaturase cDNA sequence spans 1300 nucleotides with an open reading frame encoding a 335 amino-acid protein, which has 81% identity to a Z/E11-desaturase of the redbanded leafroller moth, Argyrotaenia velutinana. A functional assay with a pYES2 yeast expression system demonstrated that the ▵11-desaturase exhibits unusual substrate and stereospecificities in producing a Z/E11 mixture (7:1) of only C14 acids. A metabolic Z9-desaturase also was cloned from fat body of this species, and proved to be in the class that produces more Z9-16:Acid than Z9-18:Acid.
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Moth desaturase characterized that produces both Z and E isomers of Δ11-tetradecenoic acids
Insect biochemistry and molecular biology, 2002Co-Authors: Weitian Liu, Marion O'connor, Hongmei Jiao, Wendell L. RoelofsAbstract:Abstract The redbanded leafroller moth, Argyrotaenia velutinana (Lepidoptera: Tortricidae) uses a 92:8 mixture of (Z)-11- and ( E )-11-tetradecenyl acetate in its pheromone blend. These are produced in the abdominal pheromone gland from the corresponding acids, which are biosynthesized in the gland in a 3:2 Z/E ratio by desaturation of myristoyl CoA. The Δ11 desaturase involved in this reaction exhibits unusual substrate and stereospecificities in specifically producing Z11 and E11 isomers of tetradecenoic acid, and exhibiting no activity with C16 and C18 precursor acids. This report describes the cloning and expression of the redbanded leafroller moth Δ11 desaturase, and compares its amino-acid sequence to those of other known insect Z9, Z10, Z11, and E11 desaturases. The metabolic Z9 desaturase from fat body tissue also was cloned and expressed, and found mainly to produce Z9-16:Acid and Z9-18:Acid. The open reading frame of the Δ11 desaturase encodes a protein with 329 amino acids, whereas the open reading frame of the Z9 desaturase encodes a protein with 351 amino acids. Addition of this new Δ11 desaturase with its different substrate and regiospecificities to the databank of characterized integral-membrane desaturases will be key in efforts to determine amino-acid mutations responsible for the wide array of unsaturated fatty-acid products.
Russell A. Jurenka - One of the best experts on this subject based on the ideXlab platform.
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regulation of pheromone biosynthesis by a brain hormone in two moth species neuroendocrine regulation pheromone biosynthesis fatty acid synthesis Argyrotaenia velutinana trichoplusia ni
2016Co-Authors: Juliet D Tang, Russell A. Jurenka, Ralph E Charlton, Walter A Wolf, P Larry, Leam Sreng, Wendell L. RoelofsAbstract:Experiments were performed to characterize the action of a brain hormone on pheromone biosynthesis in female redbanded leafroller and cabbage looper moths. Results showed that the two species differed in their respective control mechanisms. In the cabbage looper, pheromone titer from decapitated females that received either saline or brain extract injections was not significantly different from control females, suggesting that pheromone biosynthesis was not dependent on the presence of the brain hormone. In contrast, with redbanded leafroller females, studies using radiolabeled acetate incorpo- ration as well as incorporation of deuterium-labeled hexadec- anoic acid showed that (i) the brain hormone was required for pheromone biosynthesis, (ii) the brain hormone regulated pher- omone biosynthesis by activating synthesis of octadecanoyl and hexadecanoyl intermediates, and (iii) the brain hormone did not control other enzymes in the pathway. Regulation of fatty acid synthetase was unlikely since assays of the enzyme from decap- itated and normal females showed no differences in the amount or distribution of the 18- and 16-carbon acyl end products. These results in conjunction with those from organ cultures of the pheromone gland suggest that the brain hormone acts by increasing the substrate supply for fatty acid synthesis.
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Regulation of pheromone biosynthesis by a brain hormone in two moth species (neuroendocrine regulation/pheromone biosynthesis/fatty acid synthesis/Argyrotaenia velutinana/Trichoplusia ni)
2016Co-Authors: Juliet D Tang, Russell A. Jurenka, Ralph E Charlton, Walter A Wolf, P Larry, Leam Sreng, Wendell L. RoelofsAbstract:Experiments were performed to characterize the action of a brain hormone on pheromone biosynthesis in female redbanded leafroller and cabbage looper moths. Results showed that the two species differed in their respective control mechanisms. In the cabbage looper, pheromone titer from decapitated females that received either saline or brain extract injections was not significantly different from control females, suggesting that pheromone biosynthesis was not dependent on the presence of the brain hormone. In contrast, with redbanded leafroller females, studies using radiolabeled acetate incorpo- ration as well as incorporation of deuterium-labeled hexadec- anoic acid showed that (i) the brain hormone was required for pheromone biosynthesis, (ii) the brain hormone regulated pher- omone biosynthesis by activating synthesis of octadecanoyl and hexadecanoyl intermediates, and (iii) the brain hormone did not control other enzymes in the pathway. Regulation of fatty acid synthetase was unlikely since assays of the enzyme from decap- itated and normal females showed no differences in the amount or distribution of the 18- and 16-carbon acyl end products. These results in conjunction with those from organ cultures of the pheromone gland suggest that the brain hormone acts by increasing the substrate supply for fatty acid synthesis.
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Action of PBAN and related peptides on pheromone biosynthesis in isolated pheromone glands of the redbanded leafroller moth, Argyrotaenia velutinana
Comparative biochemistry and physiology. Pharmacology toxicology and endocrinology, 1994Co-Authors: Russell A. Jurenka, Gemma Fabriàs, Letitia Devoe, Wendell L. RoelofsAbstract:Abstract Isolated pheromone glands from the redbanded leafroller moth, Argyrotaenia velutinana , were utilized to demonstrate the action of pheromone biosynthesis activating neuropeptide (PBAN) and bursa pheromonotropic peptide plus several other related peptides on pheromone biosynthesis. All peptides belonging to the PBAN family and the bursa peptide stimulated pheromone biosynthesis as measured by pheromone titer and incorporation of radiolabeled acetate. These peptides required the presence of extracellular Ca 2+ for expression of full activity and several inorganic Ca 2+ channel blockers inhibited the stimulation of pheromone biosynthesis. The Ca 2+ ionophore A23187 alone stimulated pheromone biosynthesis as did a cAMP analogue. Stimulation by the cAMP analogue in the absence of extracellular Ca 2+ was observed. Maximum pheromone titers were observed in 16 hr gland incubations; however, 2–6 hr incubations were required if pheromone biosynthesis was measured by the incorporation of radiolabeled acetate. Radiolabeled glucose incorporation was not increased in the presence of PBAN. These results are discussed in the context of how the pheromone biosynthetic pathway is stimulated by these peptides.
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Control of pheromone biosynthesis in mated redbanded leafroller moths
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Russell A. Jurenka, Gemma Fabriàs, Sonny B Ramaswamy, Wendell L. RoelofsAbstract:Mating in the redbanded leafroller moth, Argyrotaenia velutinana, causes a permanent decline in pheromone titers. Three hours following the termination of mating, phermone titers were significantly decreased from premating levels, and titers remained low for at least four days after mating. Pheromone titers were similar in females that had been decapitated or mated for twenty-four hours. In the redbanded leafroller moth, two peptides control pheromone production. The pheromone biosynthesis activating neuropeptide is produced in the brain and the pheromonotropic bursa peptide is produced in the corpus bursae. Both peptides stimulated pheromone biosynthesis in mated females and extracts prepared from brains and bursae of mated females contained pheromonotropic activity. However, severing the ventral nerve cord before mating prevented the decline in pheromone titer that occurred in mated females. Hemolymph collected during scotophase from mated females did not have pheromonotropic activity, whereas hemolymph collected during scotophase from virgin females contained activity. These results indicate that mating produces a signal sent by the ventral nerve cord to the brain to stop the release of pheromone biosynthesis activating neuropeptide. © 1993 Wiley-Liss, Inc.
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Stimulation of sex pheromone production by proteinaceous extracts of the bursa copulatrix in the redbanded leafroller moth
Archives of Insect Biochemistry and Physiology, 1992Co-Authors: Gemma Fabriàs, Russell A. Jurenka, Wendell L. RoelofsAbstract:Pheromone biosynthesis in the redbanded leafroller moth, Argyrotaenia velutinana, was stimulated by homogenates of the bursa copulatrix. Although pheromonotropic activity was also extractable from the ovary, the activity of pheromone biosynthesis activating neuropeptide (PBAN) or bursa extracts was not impaired in isolated abdomens by removal of the ovary. Response to the bursa extracts was dependent on the dose administered and the time of incubation. Amounts of pheromone present in adult females of different ages appeared to be correlated with the extractable amount of pheromonotropic activity from their bursa copulatrix. Decapitation did not result in the suppression of burse factor production. Homogenates of the bursa elicited similar effects in both isolated gland and isolated abdomen incubations, but the brain neuropeptide, PBAN, was less active in the former than in the latter. Bursa extracts stimulated pheromone production in isolated abdomen incubations deprived of the bursa copulatrix, but PBAN did not. Loss of activity of bursa homogenates after treatment with either pronase E or carboxypeptidase Y indicated that the pheromonotropic factor is a proteinaceous substance. The mechanism through which pheromone production is regulated in redbanded leafroller moths is discussed. © 1992 Wiley-Liss, Inc.
Weitian Liu - One of the best experts on this subject based on the ideXlab platform.
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Moth desaturase characterized that produces both Z and E isomers of Δ11-tetradecenoic acids
Insect biochemistry and molecular biology, 2002Co-Authors: Weitian Liu, Marion O'connor, Hongmei Jiao, Wendell L. RoelofsAbstract:Abstract The redbanded leafroller moth, Argyrotaenia velutinana (Lepidoptera: Tortricidae) uses a 92:8 mixture of (Z)-11- and ( E )-11-tetradecenyl acetate in its pheromone blend. These are produced in the abdominal pheromone gland from the corresponding acids, which are biosynthesized in the gland in a 3:2 Z/E ratio by desaturation of myristoyl CoA. The Δ11 desaturase involved in this reaction exhibits unusual substrate and stereospecificities in specifically producing Z11 and E11 isomers of tetradecenoic acid, and exhibiting no activity with C16 and C18 precursor acids. This report describes the cloning and expression of the redbanded leafroller moth Δ11 desaturase, and compares its amino-acid sequence to those of other known insect Z9, Z10, Z11, and E11 desaturases. The metabolic Z9 desaturase from fat body tissue also was cloned and expressed, and found mainly to produce Z9-16:Acid and Z9-18:Acid. The open reading frame of the Δ11 desaturase encodes a protein with 329 amino acids, whereas the open reading frame of the Z9 desaturase encodes a protein with 351 amino acids. Addition of this new Δ11 desaturase with its different substrate and regiospecificities to the databank of characterized integral-membrane desaturases will be key in efforts to determine amino-acid mutations responsible for the wide array of unsaturated fatty-acid products.
Lukasz L Stelinski - One of the best experts on this subject based on the ideXlab platform.
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sprayable microencapsulated sex pheromone formulations for mating disruption of four tortricid species effects of application height rate frequency and sticker adjuvant
Journal of Economic Entomology, 2007Co-Authors: Lukasz L Stelinski, Peter Mcghee, Mike Haas, A L Ilichev, L J GutAbstract:Several application parameters of microencapsulated (MEC) sex pheromone formu- lations were manipulated to determine their impact on efÞcacy of disruption for codling moth, Cydia pomonella (L.); oriental fruit moth, Grapholita molesta (Busck); obliquebanded leafroller, Choristo- neura rosaceana (Harris); and redbanded leafroller, Argyrotaenia velutinana (Walker). Depending on the experiment, the formulations evaluated were those formerly manufactured by 3M Canada (Lon- don, ON, Canada) or those that are currently available from Suterra LLC (Bend, OR). The efÞcacy of MEC formulations applied by air-blast sprayer evenly throughout the entire canopy of 2Ð3-m-tall apple (Malus spp.) trees was equivalent to treatments in which targeted applications of MECs were made to the lower or upper 1.5 m of the canopy (at equivalent overall rates) for oriental fruit moth and both leafroller species. The realized distribution of deposited microcapsules within the tree canopy corresponded well with the intended heights of application within the canopy. The additional coapplication of the pine resin sticker Nu-Film 17 increased efÞcacy but not longevity of MEC formulations for oriental fruit moth; this adjuvant had no added effects for codling moth or leafroller formulations. Increasing the rate of active ingredient (AI) per hectare by 20 Ð30-fold (range 2.5Ð75.0 g/ha) did not improve the disruption efÞcacy of MECs for codling moth or either leafroller species when both low and high rates were applied at equivalent frequencies per season. A low-rate, high-frequency (nine applications per season) application protocol was compared with a standard protocol in which two to three applications were made per season, once before each moth generation for each species. The low-rate, high-frequency protocol resulted in equivalent or better disruption efÞcacy for each moth species, despite using two-fold less total AI per hectare per season with the former treatment. The low-rate, frequent-application protocol should make the use of MEC formu- lations of synthetic pheromone more economical and perhaps more effective.
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Behavioral and Electrophysiological Responses of Leafroller Moths to Selected Plant Extracts
Environmental Entomology, 2005Co-Authors: Ayhan Gokce, Lukasz L Stelinski, Mark E WhalonAbstract:Abstract The behavioral and electrophysiological responses of the obliquebanded leafroller, Choristoneura rosaceana (Harris), and the redbanded leafroller, Argyrotaenia velutinana (Walker), to crude extracts of Arctium lappa, Bifora radians, Humulus lupulus, Xanthium strumarium, and Verbascum spp. were studied under laboratory conditions. Plant materials were dried and ground before extraction with methanol. Plant extract residues were mixed in acetone to give 20% (wt:wt) suspensions after evaporation of excess methanol. All five plant extracts elicited significant electroantennogram (EAG) responses from both males and females of each species. EAG responses to X. strumarium were generally the highest for both species. The behavioral responses of male and female obliquebanded leafrollers to the plant extracts were compared with responses to pheromone [(Z)11–14:Ac] and a solvent control. Significantly more male and female obliquebanded leafrollers were attracted to X. strumarium compared with pheromone on f...
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behaviors of naive vs pheromone exposed leafroller moths in plumes from high dosage pheromone dispensers in a sustained flight wind tunnel implications for mating disruption of these species
Journal of Insect Behavior, 2004Co-Authors: Lukasz L Stelinski, Larry J Gut, Kevin J Vogel, James R. MillerAbstract:Brief exposures of male Choristoneura rosaceana and Argyrotaenia velutinana to the plumes generated by lures releasing 3-component pheromone blends specifically tuned for each species or by commercially distributed Isomate OBLR/PLR Plus pheromone “rope” dispensers induced markedly different subsequent behavioral responses to pheromone. A greater proportion of C. rosaceana males took flight and successfully oriented toward lures 24 h after preexposure to a lure, a rope, or the lure–rope combination in a sustained-flight wind tunnel compared to naive moths. Flights were also longer for preexposed than naive moths. Preexposed male C. rosaceana were not more likely to fly toward ropes 24 h after preexposure. By contrast, fewer male A. velutinana oriented to lures 24 h after preexposure than did naive moths. Those preexposed A. velutinana successfully locking onto plumes from lures flew for significantly shorter intervals than did unexposed moths. Electroantennograms revealed no changes at the periphery 15 min and 24 h after preexposure. For A. velutinana, the long-lasting effect was decreased attraction to a lure and increased attraction to a rope. For C. rosaceana, pheromone preexposure increased responsiveness to its authentic blend. This behavioral evidence is sufficient to explain why sexual communication of C. rosaceana is more difficult to disrupt than that of A. velutinana. Furthermore, it suggests a more complete blend of pheromone may be necessary to disrupt the former species but not the latter when using rope dispensers.
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PRESENCE OF LONG-LASTING PERIPHERAL ADAPTATION IN OBLIQUE-BANDED LEAFROLLER,Choristoneura rosaceana AND ABSENCE OF SUCH ADAPTATION IN REDBANDED LEAFROLLER,Argyrotaenia velutinana
Journal of Chemical Ecology, 2003Co-Authors: Lukasz L Stelinski, James R. MillerAbstract:Pre-exposure of male oblique-banded leafrollers, Choristoneurarosaceana (Harris), to the main component of their pheromone blend and traces of its geometric isomer (Z11–14:Ac and E11–14:Ac, respectively) at 36 ± 12 ng/ml air for durations of 15 and 60 min in sealed Teflon chambers with continuous air exchange significantly reduced peripheral sensory responses to these compounds as measured by electroantennograms (EAGs). The EAG responses of C. rosaceana to all tested dosages of pheromonal stimuli and blank controls were lowered by 55–58% and made a linear recovery to 70–100% of the pre-exposure amplitude within 12.5 min at a rate of 3–4 %/min. Exposures of 5 min were insufficient to maximally adapt C. rosaceana; however, exposures of 15 and 60 min reduced sensory responsiveness to the same minimum. In contrast, EAG responses of redbanded leafroller, Argyrotaenia velutinana (Walker), after identical pheromone exposure for 5 and 60 min yielded no long-lasting peripheral sensory adaptation as measured by EAGs, even though this species shares the same main pheromone components with C. rosaceana. We postulate that the long-lasting peripheral adaptation observed for C. rosaceana is a mechanism that impedes central nervous system habituation in this species. In contrast, A. velutinana may be more susceptible to central nervous system habituation because it lacks the capacity for minutes-long adaptation. We propose that long-lasting adaptation may be a mechanism explaining some of the variation in efficacy of pheromone-based mating disruption across taxa.
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Increased EAG responses of tortricid moths after prolonged exposure to plant volatiles: evidence for octopamine-mediated sensitization.
Journal of insect physiology, 2003Co-Authors: Lukasz L Stelinski, James R. Miller, Noah E. Ressa, Larry J GutAbstract:As measured by electroantennograms (EAG), both male and female obliquebanded leafrollers, Choristoneura rosaceana(Harris), and redbanded leafrollers, Argyrotaenia velutinana(Walker), were similarly sensitive to host-related plant volatiles: trans-2-hexenal, benzaldehyde, 1-hexenol, cis-3-hexen-1-ol, geraniol, linalool, ( +)-limonene, hexenal and trans-2-hexenol. Females of both species were similarly sensitive to the shared major component of their sex-attractant pheromone ((Z)11-14:Ac). Continuous 60 min preexposure of male and female C. rosaceana and A. velutinana to successively higher concentrations of a mixture of the nine plant volatiles in Teflon chambers with continuous air exchange caused a dosage-dependent increase in subsequent responsiveness (sensitization) to green leaf volatiles, as measured by EAGs. In addition, 60 min of pre-exposure of male C. rosaceana to certain individual volatiles ((+)-limonene, geraniol, benzaldehyde) increased EAGs nearly as much as did the mixture of nine volatiles. Pre-exposures to the nine plant-volatile mixture at concentrations achieved by 100 µg and 1 mg loading dosages in 100 µ lo f mineral oil significantly increased EAG depolarization to pheromone (cross-sensitization) in males but not females of both moth species. Antennae of male C. rosaceana pre-injected with 100 µg of octopamine (OA) without volatile pre-exposure exhibited sensitization nearly identical to that induced by pre-exposing moths to sensitizing concentrations of the plant-volatile mixture. Moreover, injection of the OA antagonist chlorpromazine (CP) blocked sensitization by the plant-volatile pre-exposure. Collectively, these findings suggest that exposures of tortricid moths to certain host-plant related volatiles may modulate subsequent olfactory sensitivity to behaviorally relevant chemical cues and that plant-volatile induced sensitization may be octopamine mediated. 2003 Elsevier Ltd. All rights reserved.
Marion O'connor - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Z/E11- and Z9-desaturases from the obliquebanded leafroller moth, Choristoneura rosaceana.
Journal of insect science (Online), 2002Co-Authors: Marion O'connor, Wendell L. RoelofsAbstract:A (triangle up) 11-desaturase gene was cloned from the sex pheromone gland of the obliquebanded leafroller moth, Choristoneura rosaceana. The desaturase cDNA sequence spans 1300 nucleotides with an open reading frame encoding a 335 amino-acid protein, which has 81% identity to a Z/E11-desaturase of the redbanded leafroller moth, Argyrotaenia velutinana. A functional assay with a pYES2 yeast expression system demonstrated that the (triangle up) 11-desaturase exhibits unusual substrate and stereospecificities in producing a Z/E11 mixture (7:1) of only C14 acids. A metabolic Z9-desaturase also was cloned from fat body of this species, and proved to be in the class that produces more Z9-16:Acid than Z9-18:Acid.
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Characterization of Z/E11- and Z9-desaturases from the obliquebanded leafroller moth, Choristoneura rosaceana
Journal of Insect Science, 2002Co-Authors: Marion O'connor, Wendell L. RoelofsAbstract:Abstract A ▵11-desaturase gene was cloned from the sex pheromone gland of the obliquebanded leafroller moth, Choristoneura rosaceana. The desaturase cDNA sequence spans 1300 nucleotides with an open reading frame encoding a 335 amino-acid protein, which has 81% identity to a Z/E11-desaturase of the redbanded leafroller moth, Argyrotaenia velutinana. A functional assay with a pYES2 yeast expression system demonstrated that the ▵11-desaturase exhibits unusual substrate and stereospecificities in producing a Z/E11 mixture (7:1) of only C14 acids. A metabolic Z9-desaturase also was cloned from fat body of this species, and proved to be in the class that produces more Z9-16:Acid than Z9-18:Acid.
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Moth desaturase characterized that produces both Z and E isomers of Δ11-tetradecenoic acids
Insect biochemistry and molecular biology, 2002Co-Authors: Weitian Liu, Marion O'connor, Hongmei Jiao, Wendell L. RoelofsAbstract:Abstract The redbanded leafroller moth, Argyrotaenia velutinana (Lepidoptera: Tortricidae) uses a 92:8 mixture of (Z)-11- and ( E )-11-tetradecenyl acetate in its pheromone blend. These are produced in the abdominal pheromone gland from the corresponding acids, which are biosynthesized in the gland in a 3:2 Z/E ratio by desaturation of myristoyl CoA. The Δ11 desaturase involved in this reaction exhibits unusual substrate and stereospecificities in specifically producing Z11 and E11 isomers of tetradecenoic acid, and exhibiting no activity with C16 and C18 precursor acids. This report describes the cloning and expression of the redbanded leafroller moth Δ11 desaturase, and compares its amino-acid sequence to those of other known insect Z9, Z10, Z11, and E11 desaturases. The metabolic Z9 desaturase from fat body tissue also was cloned and expressed, and found mainly to produce Z9-16:Acid and Z9-18:Acid. The open reading frame of the Δ11 desaturase encodes a protein with 329 amino acids, whereas the open reading frame of the Z9 desaturase encodes a protein with 351 amino acids. Addition of this new Δ11 desaturase with its different substrate and regiospecificities to the databank of characterized integral-membrane desaturases will be key in efforts to determine amino-acid mutations responsible for the wide array of unsaturated fatty-acid products.