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Yukio Ishikawa - One of the best experts on this subject based on the ideXlab platform.
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chaperonin contributes to cold hardiness of the onion maggot delia antiqua through repression of depolymerization of actin at low temperatures
PLOS ONE, 2009Co-Authors: Takumi Kayukawa, Yukio IshikawaAbstract:Winter-diapause and cold-acclimated non-diapause pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), show strong cold hardiness. To obtain insights into the mechanisms involved in the enhancement of cold hardiness, we investigated the expression patterns of genes encoding subunits of chaperonin (CCT) and the morphology of actin, a substrate of CCT, at low temperatures. Quantitative real-time PCR analyses showed the mRNA levels of CCT subunits in pupal tissues to be highly correlated with the cold hardiness of the pupae. While actin in the Malpighian tubules of non-cold-hardy pupae showed extensive depolymerization after a cold treatment, actin in the same tissue of cold-hardy pupae was not depolymerized. Damage to cell membranes became apparent after the depolymerization of actin. Moreover, administration of Latrunculin B, an inhibitor of actin polymerization, to the larvae markedly decreased the cold hardiness of the pupae obtained. These findings suggest that CCT contributes to the cold hardiness of D. antiqua through the repression of depolymerization of actin at low temperatures.
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upregulation of a desaturase is associated with the enhancement of cold hardiness in the onion maggot delia antiqua
Insect Biochemistry and Molecular Biology, 2007Co-Authors: Takumi Kayukawa, Bin Chen, Sugihiko Hoshizaki, Yukio IshikawaAbstract:Cold-acclimated non-diapause pupae, and summer- and winter-diapause pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), show marked cold hardiness as compared with intact non-diapause pupae. Homeoviscous adaptation of cellular membranes is crucial to enhance the cold hardiness of organisms, and Delta9-acyl-CoA desaturases have been assumed, albeit without experimental evidence in insects, to play a key role in the adaptation. We cloned the cDNA of a desaturase gene (Dadesat) from D. antiqua, which is most likely to encode Delta9-acyl-CoA desaturase. Expression of Dadesat mRNA in the brain, midgut, and Malpighian tubules of cold-acclimated and diapause pupae was upregulated 2-10 fold, correlating well with the increase in cold hardiness. In the pupae with enhanced cold hardiness, palmitoleic and oleic acids, the presumed products of Dadesat, in the phospholipids were significantly increased. These findings suggest that the increase in the expression of Dadesat contributes to enhanced cold hardiness in D. antiqua through the production of these unsaturated fatty acids.
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detection of chill injuries in the pupae of the onion maggot delia antiqua diptera Anthomyiidae
Applied Entomology and Zoology, 2005Co-Authors: Takumi Kayukawa, Yukio IshikawaAbstract:To clarify tissues susceptible to chill injuries in the pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), 5 d old non-diapausing pupae (ND5) were subjected to a non-freezing temperature of −20°C, with or without prior acclimation at 5°C. Cold acclimation of pupae for 8 d or longer substantially decreased the mortality after exposure to −20°C for 5 d. Analysis of the morphology of dead pupae suggested that they died at two discrete developmental stages: after formation of the adult morphology (type 1), and at a stage indistinguishable from ND5 in appearance (type 2). The two types of death were differentially induced by changing the period of −20°C treatment. A majority of pupae exhibited type 1 death after a 2 d treatment, whereas type 2 death was predominant after a 12 d treatment. Regarding the type 1 death, pharate adults appeared to have died because they failed to emerge from the puparial case. Possibly, the neuromuscular system was impaired by the short term chilling at −20°C. On the other hand, the Malpighian tubules were seriously damaged by long term chilling at −20°C, and this is thought to be the cause of type 2 death.
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expression of mrna for the t complex polypeptide 1 a subunit of chaperonin cct is upregulated in association with increased cold hardiness in delia antiqua
Cell Stress & Chaperones, 2005Co-Authors: Takumi Kayukawa, Bin Chen, Shoichiro Miyazaki, Kyo Itoyama, Tetsuro Shinoda, Yukio IshikawaAbstract:Summer-diapause and winter-diapause pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), were significantly more cold hardy than nondiapause, prediapause, and postdiapause pupae. Moreover, cold acclimation of nondiapause pupae conferred strong cold hardiness comparable with that of diapause pupae. Differential display analysis revealed that the expression of a gene encoding TCP-1 (the t-complex polypeptide–1), a subunit of chaperonin CCT, in D antiqua (DaTCP-1) is upregulated in the pupae that express enhanced cold hardiness. Quantitative real-time polymerase chain reaction analyses showed that the levels of DaTCP-1 messenger RNA in pupal tissues, brain, and midgut in particular, are highly correlated with the cold hardiness of the pupae. These findings suggest that the upregulation of DaTCP-1 expression is related to enhanced cold hardiness in D antiqua. The upregulation of CCT in response to low temperature in an organism other than the yeast is newly reported.
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dynamic changes in cold hardiness high temperature tolerance and trehalose content in the onion maggot delia antiqua diptera Anthomyiidae associated with the summer and winter diapause
Applied Entomology and Zoology, 2001Co-Authors: Michikazu Nomura, Yukio IshikawaAbstract:Changes in cold hardiness, high-temperature tolerance and trehalose content in the onion maggot, Delia antiqua (Diptera: Anthomyiidae), associated with the summer and winter diapause were investigated. Survival of summer- and winter-diapausing pupae after a 15 day exposure to −15°C was greater than 80%, while less than 5% of non-diapausing pupae survived the same treatment. Greater than 80% of winter-diapausing pupae survived −23°C for 15 days, but survival of summer-diapausing pupae at the same procedure was less than 30%. More than 75% of summer- and winter-diapausing pupae, but not non-diapausing pupae, tolerated 35°C for 15 days. Trehalose concentrations in summer- and winter-diapausing pupae were not high at the beginning of diapause (≈5 μg/mg), but increased gradually and reached 10 μg/mg in 40 days, although they were kept at relatively high temperatures of 25°C (summer diapause) or 15°C (winter diapause). Cold hardiness of pupae, however, was not proportional to their trehalose content; although trehalose concentrations in winter- and summer-diapausing pupae at day 40 (WD40 and SD40) were similar (≈10 μg/mg), cold hardiness of these pupae differed largely (WD40>SD40).
Michikazu Nomura - One of the best experts on this subject based on the ideXlab platform.
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dynamic changes in cold hardiness high temperature tolerance and trehalose content in the onion maggot delia antiqua diptera Anthomyiidae associated with the summer and winter diapause
Applied Entomology and Zoology, 2001Co-Authors: Michikazu Nomura, Yukio IshikawaAbstract:Changes in cold hardiness, high-temperature tolerance and trehalose content in the onion maggot, Delia antiqua (Diptera: Anthomyiidae), associated with the summer and winter diapause were investigated. Survival of summer- and winter-diapausing pupae after a 15 day exposure to −15°C was greater than 80%, while less than 5% of non-diapausing pupae survived the same treatment. Greater than 80% of winter-diapausing pupae survived −23°C for 15 days, but survival of summer-diapausing pupae at the same procedure was less than 30%. More than 75% of summer- and winter-diapausing pupae, but not non-diapausing pupae, tolerated 35°C for 15 days. Trehalose concentrations in summer- and winter-diapausing pupae were not high at the beginning of diapause (≈5 μg/mg), but increased gradually and reached 10 μg/mg in 40 days, although they were kept at relatively high temperatures of 25°C (summer diapause) or 15°C (winter diapause). Cold hardiness of pupae, however, was not proportional to their trehalose content; although trehalose concentrations in winter- and summer-diapausing pupae at day 40 (WD40 and SD40) were similar (≈10 μg/mg), cold hardiness of these pupae differed largely (WD40>SD40).
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biphasic effect of low temperature on completion of winter diapause in the onion maggot delia antiqua
Journal of Insect Physiology, 2000Co-Authors: Michikazu Nomura, Yukio IshikawaAbstract:Abstract The effect of low temperature on completion of winter diapause was investigated in the onion maggot, Delia antiqua (Diptera: Anthomyiidae). Diapause was completed under constant diapause-inducing conditions of 15°C and 12L–12D, without any exposure to lower temperature. The pupal period for 50% adult emergence was 117 days. None of the cold treatments at 5.6°C examined in the present study advanced adult emergence; on the contrary, they delayed it. Detailed analyses of the results revealed that diapause development in D. antiqua comprises two phases which differ in sensitivity to low temperature, with the phase shift occurring at around day 60 at 15°C and 12L–12D. In the first phase of diapause development, low temperature (5.6°C) had no effect on diapause development. In the latter phase, by contrast, diapause development was retarded in proportion to the duration of cold treatment.
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characteristics of summer diapause in the onion maggot delia antiqua diptera Anthomyiidae
Journal of Insect Physiology, 2000Co-Authors: Yukio Ishikawa, Takahisa Yamashita, Michikazu NomuraAbstract:Characteristics of summer diapause in the onion maggot, Delia antiqua, were clarified by laboratory experiments. Temperature was the primary factor for the induction of summer diapause in this species. The critical temperature for diapause induction was approximately 24 degrees C, regardless of the photoperiod. At 23 degrees C, the development of the diapausing pupae was arrested the day after pupariation, when about 7% of the total pupal development had occurred in terms of total effective temperature (degree-days). The most sensitive period for temperature with regard to diapause induction was estimated to be between pupariation and "pupation" (i.e., evagination of the head in cyclorrhaphous flies). Completion of diapause occurred at a wide range of temperatures (4-25 degrees C): The optimal temperature was approximately 16 degrees C, at which temperature only five days were required for diapause completion. The characteristics of summer diapause in D. antiqua are discussed in comparison with those of summer dormancy in a congener D. radicum and those of winter diapause in D. antiqua.
C D Rogers - One of the best experts on this subject based on the ideXlab platform.
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wheat bulb fly delia coarctata larval attraction to phenolic components of host plant root exudates
Entomologia Experimentalis Et Applicata, 2014Co-Authors: C D Rogers, K A EvansAbstract:Wheat bulb fly (WBF), Delia coarctata Fallen (Diptera: Anthomyiidae), larvae are a subterranean pest of wheat [Triticum aestivum L. (Poaceae)] and other cereals. Larvae locate host plants through chemotaxis and chemokinesis, utilising the primary plant metabolite carbon dioxide as a ‘search trigger’ and Poaceae-specific secondary plant metabolites exuded from the plant. The aim of this study was to use arena bioassays to identify further compounds involved in the host-finding process. The larval behavioural response to four concentrations of syringic and vanillic acid, chemical constituents of host-plant exudates, were tested. Analysis of the final resting position of D. coarctata larvae by the Rayleigh test of uniformity identified attraction to wheat seedling exudates and to both compounds at the lowest concentrations tested, with syringic acid concentrations being most attractive at 0.1 mg l−1 and vanillic acid being most attractive at 0.001 mg l−1. These results add more detail to the subterranean chemical ecology of this species, allowing a behavioural sequence for host-plant orientation by WBF larvae to be proposed.
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wheat bulb fly delia coarctata fallen diptera Anthomyiidae larval response to hydroxamic acid constituents of host plant root exudates
Bulletin of Entomological Research, 2013Co-Authors: C D Rogers, K EvansAbstract:Wheat bulb fly (WBF, Delia coarctata, Fallen, Diptera: Anthomyiidae) is a pest of commercial importance in wheat, barley and rye, with attacked crops failing to produce full potential yields. Females do not oviposit in association with a host-plant; therefore, prompt location of a suitable host is critical to the survival of the newly hatched larvae. The objective of this study was to conduct choice test bioassays to assess the attraction of WBF larvae to specific chemical constituents of WBF host-plant root exudates, the hydroxamic acids DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) and MBOA (6-methoxy-benzoxazolin-2-one). The larval response to four concentrations of each test compound was assessed in arena bioassays. Analysis using a Rayleigh test of uniformity of the final resting positions of larvae in response to these chemicals indicated attraction. These results go some way to explaining the mechanisms by which WBF larvae locate host plants, giving the potential to develop semiochemical based control strategies.
Takumi Kayukawa - One of the best experts on this subject based on the ideXlab platform.
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chaperonin contributes to cold hardiness of the onion maggot delia antiqua through repression of depolymerization of actin at low temperatures
PLOS ONE, 2009Co-Authors: Takumi Kayukawa, Yukio IshikawaAbstract:Winter-diapause and cold-acclimated non-diapause pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), show strong cold hardiness. To obtain insights into the mechanisms involved in the enhancement of cold hardiness, we investigated the expression patterns of genes encoding subunits of chaperonin (CCT) and the morphology of actin, a substrate of CCT, at low temperatures. Quantitative real-time PCR analyses showed the mRNA levels of CCT subunits in pupal tissues to be highly correlated with the cold hardiness of the pupae. While actin in the Malpighian tubules of non-cold-hardy pupae showed extensive depolymerization after a cold treatment, actin in the same tissue of cold-hardy pupae was not depolymerized. Damage to cell membranes became apparent after the depolymerization of actin. Moreover, administration of Latrunculin B, an inhibitor of actin polymerization, to the larvae markedly decreased the cold hardiness of the pupae obtained. These findings suggest that CCT contributes to the cold hardiness of D. antiqua through the repression of depolymerization of actin at low temperatures.
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upregulation of a desaturase is associated with the enhancement of cold hardiness in the onion maggot delia antiqua
Insect Biochemistry and Molecular Biology, 2007Co-Authors: Takumi Kayukawa, Bin Chen, Sugihiko Hoshizaki, Yukio IshikawaAbstract:Cold-acclimated non-diapause pupae, and summer- and winter-diapause pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), show marked cold hardiness as compared with intact non-diapause pupae. Homeoviscous adaptation of cellular membranes is crucial to enhance the cold hardiness of organisms, and Delta9-acyl-CoA desaturases have been assumed, albeit without experimental evidence in insects, to play a key role in the adaptation. We cloned the cDNA of a desaturase gene (Dadesat) from D. antiqua, which is most likely to encode Delta9-acyl-CoA desaturase. Expression of Dadesat mRNA in the brain, midgut, and Malpighian tubules of cold-acclimated and diapause pupae was upregulated 2-10 fold, correlating well with the increase in cold hardiness. In the pupae with enhanced cold hardiness, palmitoleic and oleic acids, the presumed products of Dadesat, in the phospholipids were significantly increased. These findings suggest that the increase in the expression of Dadesat contributes to enhanced cold hardiness in D. antiqua through the production of these unsaturated fatty acids.
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detection of chill injuries in the pupae of the onion maggot delia antiqua diptera Anthomyiidae
Applied Entomology and Zoology, 2005Co-Authors: Takumi Kayukawa, Yukio IshikawaAbstract:To clarify tissues susceptible to chill injuries in the pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), 5 d old non-diapausing pupae (ND5) were subjected to a non-freezing temperature of −20°C, with or without prior acclimation at 5°C. Cold acclimation of pupae for 8 d or longer substantially decreased the mortality after exposure to −20°C for 5 d. Analysis of the morphology of dead pupae suggested that they died at two discrete developmental stages: after formation of the adult morphology (type 1), and at a stage indistinguishable from ND5 in appearance (type 2). The two types of death were differentially induced by changing the period of −20°C treatment. A majority of pupae exhibited type 1 death after a 2 d treatment, whereas type 2 death was predominant after a 12 d treatment. Regarding the type 1 death, pharate adults appeared to have died because they failed to emerge from the puparial case. Possibly, the neuromuscular system was impaired by the short term chilling at −20°C. On the other hand, the Malpighian tubules were seriously damaged by long term chilling at −20°C, and this is thought to be the cause of type 2 death.
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expression of mrna for the t complex polypeptide 1 a subunit of chaperonin cct is upregulated in association with increased cold hardiness in delia antiqua
Cell Stress & Chaperones, 2005Co-Authors: Takumi Kayukawa, Bin Chen, Shoichiro Miyazaki, Kyo Itoyama, Tetsuro Shinoda, Yukio IshikawaAbstract:Summer-diapause and winter-diapause pupae of the onion maggot, Delia antiqua (Diptera: Anthomyiidae), were significantly more cold hardy than nondiapause, prediapause, and postdiapause pupae. Moreover, cold acclimation of nondiapause pupae conferred strong cold hardiness comparable with that of diapause pupae. Differential display analysis revealed that the expression of a gene encoding TCP-1 (the t-complex polypeptide–1), a subunit of chaperonin CCT, in D antiqua (DaTCP-1) is upregulated in the pupae that express enhanced cold hardiness. Quantitative real-time polymerase chain reaction analyses showed that the levels of DaTCP-1 messenger RNA in pupal tissues, brain, and midgut in particular, are highly correlated with the cold hardiness of the pupae. These findings suggest that the upregulation of DaTCP-1 expression is related to enhanced cold hardiness in D antiqua. The upregulation of CCT in response to low temperature in an organism other than the yeast is newly reported.
K Evans - One of the best experts on this subject based on the ideXlab platform.
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wheat bulb fly delia coarctata fallen diptera Anthomyiidae larval response to hydroxamic acid constituents of host plant root exudates
Bulletin of Entomological Research, 2013Co-Authors: C D Rogers, K EvansAbstract:Wheat bulb fly (WBF, Delia coarctata, Fallen, Diptera: Anthomyiidae) is a pest of commercial importance in wheat, barley and rye, with attacked crops failing to produce full potential yields. Females do not oviposit in association with a host-plant; therefore, prompt location of a suitable host is critical to the survival of the newly hatched larvae. The objective of this study was to conduct choice test bioassays to assess the attraction of WBF larvae to specific chemical constituents of WBF host-plant root exudates, the hydroxamic acids DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) and MBOA (6-methoxy-benzoxazolin-2-one). The larval response to four concentrations of each test compound was assessed in arena bioassays. Analysis using a Rayleigh test of uniformity of the final resting positions of larvae in response to these chemicals indicated attraction. These results go some way to explaining the mechanisms by which WBF larvae locate host plants, giving the potential to develop semiochemical based control strategies.