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Seiji Tanaka - One of the best experts on this subject based on the ideXlab platform.
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Endocrine mechanisms controlling body-color polymorphism in locusts
Archives of Insect Biochemistry and Physiology, 2020Co-Authors: Seiji TanakaAbstract:The present article reviews recent published and unpublished findings on the hormonal mechanisms for the control of body-color polymorphism in locusts. Emphasis is placed on the dark color–inducing factors and their role in the induction of various types of body coloration observed under different environmental conditions. Implantation of corpora cardiaca (CC) taken from normal nymphs of Locusta migratoria induced dark color in nymphs of an albino strain. Using the albino strain for the bioassay, a neuropeptide, [His7]-Corazonin, was identified as a dark color–inducing factor for L. migratoria and Schistocerca gregaria. In the former, depending upon the dose and timing of the injection, this peptide and juvenile hormone developed various body colors looking like those found in nature. The body coloration characteristic of gregarious forms was also induced in isolated albino nymphs and field-collected solitary nymphs. In S. gregaria, on the other hand, the peptide induced black patterns, but the orange or yellow background color observed in gregarious forms was not induced when the peptide was injected into solitary individuals. [His7]-Corazonin also induced darkening in other grasshoppers and locusts, but not in katydids. Albino L. migratoria developed dark color when implanted with brains or CC taken from other insects belonging to 10 major insect orders, but not with those from Coleoptera. [His7]-Corazonin or a similar compound is widespread among insects and plays a pivotal role in controlling body color in some species and presumably other physiological roles in other species. Arch. Insect Biochem. Physiol. 47:139–149, 2001. © 2001 Wiley-Liss, Inc.
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Mass spectrometric evidence for the deficiency in the dark‐color‐inducing hormone, [His7]‐Corazonin in an albino strain of Locusta migratoria as well as for its presence in solitary Schistocerca gregaria
Archives of Insect Biochemistry and Physiology, 2020Co-Authors: Geert Baggerman, Seiji Tanaka, Arnold De Loof, Michael Breuer, Dirk Veelaert, Elke Clynen, Rahman Mazibur, Liliane SchoofsAbstract:A factor present in the brain and corpus cardiacum responsible for the induction of dark colour in Locusta migratoria was recently isolated and identified from the corpora cardiaca of normally pigmented locusts. The purification of this factor, designated as [His7]-Corazonin was monitored using an albino mutant from a laboratory colony of an Okinawa (Japan) strain. In this study, we provide unequivocal mass spectrometric evidence that the brain and the corpora cardiaca of this albino Locusta mutant are deficient in [His7]-Corazonin. Previously, [His7]-Corazonin was shown to be responsible for the induction of dark body colour patterns as observed in crowded locusts. Using nanoflow-liquid chromatography-mass spectrometry, we demonstrated that this dark colour–inducing hormone is, however, present in the corpora cardiaca of solitary locusts (Schistocerca gregaria). Arch. Insect Biochem. Physiol. 47:150–160, 2001. © 2001 Wiley-Liss, Inc.
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Functional characterization of the Corazonin-encoding gene in phase polyphenism of the migratory locust, Locusta migratoria (Orthoptera: Acrididae)
Applied Entomology and Zoology, 2016Co-Authors: Ryohei Sugahara, Seiji Tanaka, Akiya Jouraku, Takahiro ShiotsukiAbstract:Locusts exhibit phase polyphenism in which phase transition between the solitarious (isolation-reared) and gregarious (crowd-reared) phenotypes occurs in response to crowding conditions. Phase transformation from solitarious to gregarious nymphs is accompanied by darkening of the body color and changes in classical morphometric ratios such as F / C ( F hind femur length; C maximum head width). These changes occur in the absence of crowding if solitarious locusts are injected with the neuropeptide, Corazonin (Crz). This study investigated the effects of the knockdown of the CRZ gene on body color and morphometric characteristics in the migratory locust Locusta migratoria (L.) (Orthoptera: Acrididae). An injection of dsRNA for Crz significantly reduced CRZ mRNA levels and reduced the intensity of darkening on the pronotum in nymphs. The silencing of CRZ expression in gregarious nymphs shifted the F / C toward a value typical of the solitarious form in the adult stage. However, the expression profiles of CRZ were similar between the gregarious and solitarious nymphs. Therefore, we conclude that Crz is responsible for phase-dependent changes in darkening and the morphometric ratio; however, these changes are not controlled through differential CRZ expression at the transcriptional level.
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are juvenile hormone and his7 Corazonin related to maternal regulation of progeny phase characteristics in the migratory locust locusta migratoria
African Entomology, 2016Co-Authors: Ben A Hamouda, Seiji TanakaAbstract:The role of juvenile hormone (JH) and Corazonin in the maternal regulation of progeny characteristics was examined in the migratory locust, Locusta migratoria (Orthoptera: Acrididae). Crowded female adults are known to produce large eggs, heavier and darker hatchlings than solitarious female adults which produce smaller eggs, smaller hatchlings with brighter cuticular colour. Implantation of corpora allata (CA) taken from gregarious sexually mature females caused crowded females to deposit smaller eggs and smaller, lighter hatchlings. The neuropeptide [His7]-Corazonin, present in the central nervous system and corpus cardiacum, is known to induce darkening of body colouration when injected into locusts reared in isolation. To examine whether this neuropeptide is responsible for the maternal regulation of progeny phase characteristics, 1 nmol [His7]-Corazonin mixed with 2 µl of sunflower oil were injected twice into solitarious female adults. No effect of Corazonin on egg size, the weight of the hatchlings...
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dispersion of peptides in vegetable oil as a simple slow release formula for both injection and oral uptake in insects a case study with his7 Corazonin in an albino locusta migratoria deficient in Corazonin
Peptides, 2011Co-Authors: Bart Boerjan, Seiji Tanaka, Arnold De Loof, Liliane SchoofsAbstract:Upon realizing that for drug delivery in the body, lipidization is a technique used in the pharmaceutical industry, we took in consideration that Corazonin melanizes the cuticle of albino Locusta migratoria only when injected in an emulsion in oil, not when applied in a watery solution. In this study, we investigate the possibility for oral uptake of Corazonin dispersed in oil, and validated the activity by a melanization assay. Not only was it active, it also induced red cuticular coloration in some animals, and it was also unexpectedly lethal for nymphs, but not for adults. These results necessitate the revision of the potential of (some) peptides for insect control. Also, they suggest practical recommendations for the application of other peptides in physiological assays where oil could be used as a simple slow release formula.
Liliane Schoofs - One of the best experts on this subject based on the ideXlab platform.
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Mass spectrometric evidence for the deficiency in the dark‐color‐inducing hormone, [His7]‐Corazonin in an albino strain of Locusta migratoria as well as for its presence in solitary Schistocerca gregaria
Archives of Insect Biochemistry and Physiology, 2020Co-Authors: Geert Baggerman, Seiji Tanaka, Arnold De Loof, Michael Breuer, Dirk Veelaert, Elke Clynen, Rahman Mazibur, Liliane SchoofsAbstract:A factor present in the brain and corpus cardiacum responsible for the induction of dark colour in Locusta migratoria was recently isolated and identified from the corpora cardiaca of normally pigmented locusts. The purification of this factor, designated as [His7]-Corazonin was monitored using an albino mutant from a laboratory colony of an Okinawa (Japan) strain. In this study, we provide unequivocal mass spectrometric evidence that the brain and the corpora cardiaca of this albino Locusta mutant are deficient in [His7]-Corazonin. Previously, [His7]-Corazonin was shown to be responsible for the induction of dark body colour patterns as observed in crowded locusts. Using nanoflow-liquid chromatography-mass spectrometry, we demonstrated that this dark colour–inducing hormone is, however, present in the corpora cardiaca of solitary locusts (Schistocerca gregaria). Arch. Insect Biochem. Physiol. 47:150–160, 2001. © 2001 Wiley-Liss, Inc.
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dispersion of peptides in vegetable oil as a simple slow release formula for both injection and oral uptake in insects a case study with his7 Corazonin in an albino locusta migratoria deficient in Corazonin
Peptides, 2011Co-Authors: Bart Boerjan, Seiji Tanaka, Arnold De Loof, Liliane SchoofsAbstract:Upon realizing that for drug delivery in the body, lipidization is a technique used in the pharmaceutical industry, we took in consideration that Corazonin melanizes the cuticle of albino Locusta migratoria only when injected in an emulsion in oil, not when applied in a watery solution. In this study, we investigate the possibility for oral uptake of Corazonin dispersed in oil, and validated the activity by a melanization assay. Not only was it active, it also induced red cuticular coloration in some animals, and it was also unexpectedly lethal for nymphs, but not for adults. These results necessitate the revision of the potential of (some) peptides for insect control. Also, they suggest practical recommendations for the application of other peptides in physiological assays where oil could be used as a simple slow release formula.
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cloning and characterization of a third isoform of Corazonin in the honey bee apis mellifera
Peptides, 2006Co-Authors: Peter Verleyen, Geert Baggerman, Inge Mertens, Tim Vandersmissen, Jurgen Huybrechts, Alfons Van Lommel, Arnold De Loof, Liliane SchoofsAbstract:The precursor of the insect hormone Corazonin has been cloned from the honey bee Apis mellifera. The precursor predicts a novel isoform of Corazonin, pQTFTYSHGWTNamide, which was confirmed by tandem mass spectrometry. Although Apis Corazonin differs only by a glutamine/threonine substitution from [His7]-Corazonin, it is considerably less active in the dark color inducing assay on albino locusts. Whole mount fluorescence immunohistochemistry of the central nervous system of the honey bee showed a pattern similar to the ones described for other insects. Four neurons of the lateral protocerebrum project axons towards the retrocerebral complex. It is unlikely that Apis Corazonin is present in all hymenopteran species since the presence of this peptide could not be demonstrated by means of mass spectrometry in the retrocerebral complex of the red wood ant Formica rufa and the wasp Vespula saxonica. Instead, we found masses corresponding with [Arg7]- and [His7]-Corazonin respectively, suggesting that some of the Corazonin isoforms originated late during evolution in different insect orders.
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presence of his 7 Corazonin in the central nervous system of a newly isolated albino strain of schistocerca gregaria orthoptera acrididae mass spectrometric and immunocytochemical evidence
European Journal of Endocrinology, 2003Co-Authors: Mazibur Rahman, Geert Baggerman, Arnold De Loof, Liliane Schoofs, Michael BreuerAbstract:An inbred strain of a newly isolated spontaneous albino mutant of Schistocerca gregaria (Forsk.) was examined for the presence of the neuropeptide [His7]-Corazonin by immunocytochemical and mass spectrometric methods. It was concluded that this peptide is definitely present in a limited number of neurosecretory cells in the pars lateralis as well as in the corpora cardiaca (CC). Injection of either synthetic [His7]-Corazonin or of extracts of CC of the normal coloured phenotype of S. gregaria failed to induce darkening of the cuticle, while albino Locusta migratoria, used as a positive control, turned dark. The conclusion is that the cause of albinism in the new S. gregaria albino is probably due to a defect in the receptor system for [His7]-Corazonin or in the biosynthetic pathway of melanin.
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mass spectrometric evidence for the deficiency in the dark color inducing hormone his7 Corazonin in an albino strain of locusta migratoria as well as for its presence in solitary schistocerca gregaria
Archives of Insect Biochemistry and Physiology, 2001Co-Authors: Geert Baggerman, Seiji Tanaka, Arnold De Loof, Michael Breuer, Dirk Veelaert, Elke Clynen, Rahman Mazibur, Liliane SchoofsAbstract:A factor present in the brain and corpus cardiacum responsible for the induction of dark colour in Locusta migratoria was recently isolated and identified from the corpora cardiaca of normally pigmented locusts. The purification of this factor, designated as [His7]-Corazonin was monitored using an albino mutant from a laboratory colony of an Okinawa (Japan) strain. In this study, we provide unequivocal mass spectrometric evidence that the brain and the corpora cardiaca of this albino Locusta mutant are deficient in [His7]-Corazonin. Previously, [His7]-Corazonin was shown to be responsible for the induction of dark body colour patterns as observed in crowded locusts. Using nanoflow-liquid chromatography-mass spectrometry, we demonstrated that this dark colour–inducing hormone is, however, present in the corpora cardiaca of solitary locusts (Schistocerca gregaria). Arch. Insect Biochem. Physiol. 47:150–160, 2001. © 2001 Wiley-Liss, Inc.
Michael Breuer - One of the best experts on this subject based on the ideXlab platform.
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Mass spectrometric evidence for the deficiency in the dark‐color‐inducing hormone, [His7]‐Corazonin in an albino strain of Locusta migratoria as well as for its presence in solitary Schistocerca gregaria
Archives of Insect Biochemistry and Physiology, 2020Co-Authors: Geert Baggerman, Seiji Tanaka, Arnold De Loof, Michael Breuer, Dirk Veelaert, Elke Clynen, Rahman Mazibur, Liliane SchoofsAbstract:A factor present in the brain and corpus cardiacum responsible for the induction of dark colour in Locusta migratoria was recently isolated and identified from the corpora cardiaca of normally pigmented locusts. The purification of this factor, designated as [His7]-Corazonin was monitored using an albino mutant from a laboratory colony of an Okinawa (Japan) strain. In this study, we provide unequivocal mass spectrometric evidence that the brain and the corpora cardiaca of this albino Locusta mutant are deficient in [His7]-Corazonin. Previously, [His7]-Corazonin was shown to be responsible for the induction of dark body colour patterns as observed in crowded locusts. Using nanoflow-liquid chromatography-mass spectrometry, we demonstrated that this dark colour–inducing hormone is, however, present in the corpora cardiaca of solitary locusts (Schistocerca gregaria). Arch. Insect Biochem. Physiol. 47:150–160, 2001. © 2001 Wiley-Liss, Inc.
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degradation profile of his7 Corazonin in the hemolymph of the desert locust schistocerca gregaria
Peptides, 2006Co-Authors: Tim Vandersmissen, Geert Baggerman, Jurgen Huybrechts, Arnold De Loof, B Hoste, Patrick Chaltin, Paul Proost, Michael BreuerAbstract:Degradation of the neuropeptide [His7]-Corazonin, a key hormone in phase transition in locusts was studied using [3H][His7]-Corazonin, RP-HPLC and mass spectrometry. After 4h incubation, 50 and 75% of [His7]-Corazonin could still be found in hemolymph of gregarious and solitarious Schistocerca gregaria, respectively. Under in vivo conditions the half-life was 30 min. These results are in contrast to many other neuropeptides that usually have half lives of a few minutes. The peptide is cleaved first by an endopeptidase, either just before or after the Tyr residue at position 5. Next, the C-terminal degradation fragments are further degraded by a dipeptidyl-peptidase, whereas the N-terminal fragments are further broken down one amino acid at a time. In addition, [Dopa5][His7]-Corazonin was detected. Upon synthesis, this unexpected molecular modification turned out to be biologically active in bringing about cuticular melanization.
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effect of his7 Corazonin on the number of antennal sensilla in locusta migratoria
Physiological Entomology, 2004Co-Authors: Mami Yamamotokihara, Michael Breuer, Tamako Hata, Seiji TanakaAbstract:Certain types of antennal sensilla are known to be more abundant in solitarious individuals than in gregarious ones in the migratory locust, Locusta migratoria. We tested the hypothesis that injection of a neurohormone, (His 7 )- Corazonin, into isolated-reared nymphs of this species mimics the effect of crowd- ing on the frequencies of various types of antennal sensilla. One nmol of the hormone was injected into nymphs on two occasions, on the third days of the second and third stadia, respectively. Upon adult emergence, the numbers of different types of sensilla on the eighth antennal segment were compared with those of oil-injected controls. (His 7 )-Corazonin did not influence the numbers of basiconic sensilla type A, basiconic sensilla type B and trichoid sensilla signifi- cantly compared to oil-injected controls. However, the number of coeloconic sensilla was reduced significantly by the hormone injections. Because the length of the antennal segment was not affected by the hormone injection, it appears that the hormone influenced the development of coeloconic sensilla. The results sup- port the hypothesis tested and are consistent with the idea that (His 7 )-Corazonin plays an important role in the control of phase polymorphism in L. migratoria.
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Corazonin promotes tegumentary pigment migration in the crayfish procambarus clarkii
Peptides, 2003Co-Authors: M G Porras, A De Loof, Michael Breuer, H ArechigaAbstract:Abstract The undecapeptide Corazonin (pGlu-Thr-Phe-Gln-Tyr-Ser-His-Gly-Trp-Thr-AsnNH 2 ) elicits a retraction of erythrophore pigment granules and dispersion of leucophore pigment granules in the crayfish Procambarus clarkii . The effects are dose-dependent from 10 −10 to 10 −5 M. Influence on erythrophores is lower than that of Red Pigment Concentrating Hormone (RPCH), which is inactive on leucophores. Corazonin effects are partly blocked by an anti-Corazonin antibody, and even less by an anti-RPCH antibody. Corazonin effects are completely suppressed by the calcium chelator BAPTA. Immunoreactive somata and fibers were identified in various regions of the eyestalk (medulla terminalis, medulla interna and medulla externa) with the anti-Corazonin antibody. These results suggest the possible existence of a Corazonin-like peptide in crustaceans.
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behavioural differences in locusta migratoria associated with albinism and their relation to his7 Corazonin
Physiological Entomology, 2003Co-Authors: Bruno Hoste, Arnold De Loof, Stephen J Simpson, Michael BreuerAbstract:The neuropeptide (His 7 )-Corazonin induces black colouration in locusts, a feature typically occurring in gregariousanimals . To date, the function of this neuropeptide in relation to phase transition has not been fully clarified. Unan- swered questions on its involvement in behavioural and morphometrical phase- shifting and possible temperature-induced regulation still remain. In the African locust, Locusta migratoria migratorioides (Reiche and Fairmaire) (Orthoptera: Acrididae), the gregarious form possesses mainly a brown colouration with typical intense black pigmentation. To find a possible behavioural function, an albino L. migratoria mutant, deficient in (His 7 )-Corazonin and thuslacking the typical gregarious colour, was used. Between these two phenotypes, nonphase specific behavioural differences in a phase-dependent behavioural set-up were found. Additionally, a wild-type of the Okinawa strain was screened behaviourally and located in comparison to the other groups. Treatment of albinos with Corazonin induced normal phenotype behaviour. The degree of interference of Corazonin in relation to these findings and a possible effect at the level of visual perception is discussed.
Arnold De Loof - One of the best experts on this subject based on the ideXlab platform.
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Mass spectrometric evidence for the deficiency in the dark‐color‐inducing hormone, [His7]‐Corazonin in an albino strain of Locusta migratoria as well as for its presence in solitary Schistocerca gregaria
Archives of Insect Biochemistry and Physiology, 2020Co-Authors: Geert Baggerman, Seiji Tanaka, Arnold De Loof, Michael Breuer, Dirk Veelaert, Elke Clynen, Rahman Mazibur, Liliane SchoofsAbstract:A factor present in the brain and corpus cardiacum responsible for the induction of dark colour in Locusta migratoria was recently isolated and identified from the corpora cardiaca of normally pigmented locusts. The purification of this factor, designated as [His7]-Corazonin was monitored using an albino mutant from a laboratory colony of an Okinawa (Japan) strain. In this study, we provide unequivocal mass spectrometric evidence that the brain and the corpora cardiaca of this albino Locusta mutant are deficient in [His7]-Corazonin. Previously, [His7]-Corazonin was shown to be responsible for the induction of dark body colour patterns as observed in crowded locusts. Using nanoflow-liquid chromatography-mass spectrometry, we demonstrated that this dark colour–inducing hormone is, however, present in the corpora cardiaca of solitary locusts (Schistocerca gregaria). Arch. Insect Biochem. Physiol. 47:150–160, 2001. © 2001 Wiley-Liss, Inc.
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dispersion of peptides in vegetable oil as a simple slow release formula for both injection and oral uptake in insects a case study with his7 Corazonin in an albino locusta migratoria deficient in Corazonin
Peptides, 2011Co-Authors: Bart Boerjan, Seiji Tanaka, Arnold De Loof, Liliane SchoofsAbstract:Upon realizing that for drug delivery in the body, lipidization is a technique used in the pharmaceutical industry, we took in consideration that Corazonin melanizes the cuticle of albino Locusta migratoria only when injected in an emulsion in oil, not when applied in a watery solution. In this study, we investigate the possibility for oral uptake of Corazonin dispersed in oil, and validated the activity by a melanization assay. Not only was it active, it also induced red cuticular coloration in some animals, and it was also unexpectedly lethal for nymphs, but not for adults. These results necessitate the revision of the potential of (some) peptides for insect control. Also, they suggest practical recommendations for the application of other peptides in physiological assays where oil could be used as a simple slow release formula.
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cloning and characterization of a third isoform of Corazonin in the honey bee apis mellifera
Peptides, 2006Co-Authors: Peter Verleyen, Geert Baggerman, Inge Mertens, Tim Vandersmissen, Jurgen Huybrechts, Alfons Van Lommel, Arnold De Loof, Liliane SchoofsAbstract:The precursor of the insect hormone Corazonin has been cloned from the honey bee Apis mellifera. The precursor predicts a novel isoform of Corazonin, pQTFTYSHGWTNamide, which was confirmed by tandem mass spectrometry. Although Apis Corazonin differs only by a glutamine/threonine substitution from [His7]-Corazonin, it is considerably less active in the dark color inducing assay on albino locusts. Whole mount fluorescence immunohistochemistry of the central nervous system of the honey bee showed a pattern similar to the ones described for other insects. Four neurons of the lateral protocerebrum project axons towards the retrocerebral complex. It is unlikely that Apis Corazonin is present in all hymenopteran species since the presence of this peptide could not be demonstrated by means of mass spectrometry in the retrocerebral complex of the red wood ant Formica rufa and the wasp Vespula saxonica. Instead, we found masses corresponding with [Arg7]- and [His7]-Corazonin respectively, suggesting that some of the Corazonin isoforms originated late during evolution in different insect orders.
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degradation profile of his7 Corazonin in the hemolymph of the desert locust schistocerca gregaria
Peptides, 2006Co-Authors: Tim Vandersmissen, Geert Baggerman, Jurgen Huybrechts, Arnold De Loof, B Hoste, Patrick Chaltin, Paul Proost, Michael BreuerAbstract:Degradation of the neuropeptide [His7]-Corazonin, a key hormone in phase transition in locusts was studied using [3H][His7]-Corazonin, RP-HPLC and mass spectrometry. After 4h incubation, 50 and 75% of [His7]-Corazonin could still be found in hemolymph of gregarious and solitarious Schistocerca gregaria, respectively. Under in vivo conditions the half-life was 30 min. These results are in contrast to many other neuropeptides that usually have half lives of a few minutes. The peptide is cleaved first by an endopeptidase, either just before or after the Tyr residue at position 5. Next, the C-terminal degradation fragments are further degraded by a dipeptidyl-peptidase, whereas the N-terminal fragments are further broken down one amino acid at a time. In addition, [Dopa5][His7]-Corazonin was detected. Upon synthesis, this unexpected molecular modification turned out to be biologically active in bringing about cuticular melanization.
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behavioural differences in locusta migratoria associated with albinism and their relation to his7 Corazonin
Physiological Entomology, 2003Co-Authors: Bruno Hoste, Arnold De Loof, Stephen J Simpson, Michael BreuerAbstract:The neuropeptide (His 7 )-Corazonin induces black colouration in locusts, a feature typically occurring in gregariousanimals . To date, the function of this neuropeptide in relation to phase transition has not been fully clarified. Unan- swered questions on its involvement in behavioural and morphometrical phase- shifting and possible temperature-induced regulation still remain. In the African locust, Locusta migratoria migratorioides (Reiche and Fairmaire) (Orthoptera: Acrididae), the gregarious form possesses mainly a brown colouration with typical intense black pigmentation. To find a possible behavioural function, an albino L. migratoria mutant, deficient in (His 7 )-Corazonin and thuslacking the typical gregarious colour, was used. Between these two phenotypes, nonphase specific behavioural differences in a phase-dependent behavioural set-up were found. Additionally, a wild-type of the Okinawa strain was screened behaviourally and located in comparison to the other groups. Treatment of albinos with Corazonin induced normal phenotype behaviour. The degree of interference of Corazonin in relation to these findings and a possible effect at the level of visual perception is discussed.
Jan A Veenstra - One of the best experts on this subject based on the ideXlab platform.
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reprint of the distribution and physiological effects of three evolutionarily and sequence related neuropeptides in rhodnius prolixus adipokinetic hormone Corazonin and adipokinetic hormone Corazonin related peptide
General and Comparative Endocrinology, 2014Co-Authors: H Patel, Jan A Veenstra, Ian Orchard, Angela B LangeAbstract:We have examined the distribution and physiological effects of three evolutionarily and sequence-related neuropeptides in Rhodnius prolixus. These neuropeptides, adipokinetic hormone (RhoprAKH), Corazonin (CRZ) and adipokinetic hormone/Corazonin-related peptide (RhoprACP) are present in distinct, non-overlapping neuronal subsets in the central nervous system (CNS), as determined by immunohistochemistry. Corazonin-like immunoreactive cell bodies are present in the brain and ventral nerve cord, whereas ACP-like immunoreactive cell bodies are only present in the brain, and AKH-like immunoreactive cell bodies only present in the corpus cardiacum (CC). The immunoreactivity to ACP, CRZ and AKH in R. prolixus suggests that ACP and CRZ are released within the CNS, and that CRZ and AKH are released as neurohormones from the CC. Injection of RhoprAKH into adult males elevated haemolymph lipid levels, but injection of CRZ or RhoprACP failed to have any effect on haemolymph lipid levels. Corazonin stimulated an increase in heart-beat frequency in vitro, but RhoprAKH and RhoprACP failed to do so. Thus, although all three neuropeptides share sequence similarity, the AKH and CRZ receptors only respond to their own ligand.
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In silico cloning of genes encoding neuropeptides, neurohormones and their putative G-protein coupled receptors in a spider mite.
Insect Biochemistry and Molecular Biology, 2011Co-Authors: Jan A Veenstra, Stephane Rombauts, Miodrag GrbićAbstract:Abstract The genome of the spider mite was prospected for the presence of genes coding neuropeptides, neurohormones and their putative G-protein coupled receptors. Fifty one candidate genes were found to encode neuropeptides or neurohormones. These include all known insect neuropeptides and neurohormones, with the exception of sulfakinin, Corazonin, neuroparsin and PTTH. True orthologs of adipokinetic hormone (AKH) were neither found, but there are three genes encoding peptides similar in structure to both AKH and the AKH-Corazonin-related peptide. We were also unable to identify the precursors for pigment dispersing factor (PDF) or the recently discovered trissin. However, the spider mite probably does have such genes, as we found their putative receptors. A novel arthropod neuropeptide gene was identified that shows similarity to previously described molluscan neuropeptide genes and was called EFLamide. A total of 65 putative neuropeptide GPCR genes were also identifieid, of these 58 belong to the A-family and 7 to the B-family. Phylogenetic analysis showed that 50 of them are closely related to insect GPCRs, which allowed the identification of their putative ligand in 39 cases with varying degrees of certainty. Other spider mite GPCRs however have no identifiable orthologs in the genomes of the four holometabolous insect species best analyzed. Whereas some of the latter have orthologs in hemimetabolous insect species, crustaceans or ticks, for others such arthropod homologs are currently unknown.
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does Corazonin signal nutritional stress in insects
Insect Biochemistry and Molecular Biology, 2009Co-Authors: Jan A VeenstraAbstract:The undecapeptide Corazonin, initially discovered from the American cockroach as a strong cardioaccelerator, is now known to be ubiquitously present in arthropods, although it is absent from some species, notably Coleoptera. The structure of its precursor is similar to the GnRH precursor, while it acts through a receptor related to the GnRH receptor; Corazonin thus appears to be an arthropod homolog of GnRH. It is produced by neuroendocrine cells in the brain, as well as interneurons in the ventral nerve cord. These two cell types are generally present in insects; in most species there are also other neurons producing Corazonin. Its function in insects has remained obscure; its cardioacceleratory effects are limited to a few cockroach species, while in other species different physiological effects have been described. Most spectacularly it induces changes associated with the gregarious phase in migratory locusts and in the silkworm it reduces the size of the cocoon formed. Corazonin is able to induce ecdysis in two moth species, however locusts and flies in which the Corazonin gene is no longer expressed, ecdyse normally and, hence, it is not clear whether Corazonin is essential for ecdysis. As the Corazonin neuroendocrine cells in the brain express receptors for two midgut peptides, it seems likely that their activity is modulated by the midgut endocrine cells. I propose that in insects Corazonin might be released under conditions of nutritional stress, which can explain several of the observed physiological effects of this neurohormone.
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postembryonic development of Corazonin containing neurons and neurosecretory cells in the blowfly phormia terraenovae
The Journal of Comparative Neurology, 1994Co-Authors: Rafael Cantera, Dick R Nassel, Jan A VeenstraAbstract:An antiserum against the cockroach cardioactive peptide Corazonin was used to investigate the distribution of immunoreactive neurons and neurosecretory cells in the nervous system of the blowfly, Phormia terraenovae, during postembryonic development. A small number of Corazonin-immunoreactive neurons was found at larval, pupal, and adult stages. At all postembryonic stages two cell groups were found in the protocerebrum of the brain: (1) two lateral cell clusters and (2) two median cells. In the larva eight bilateral cell pairs were found in thoracic and abdominal neuromeres of the fused ventral ganglion. The lateral brain neurons are located in the lateral neurosecretory cell group and extend axons with branches in several components of the retrocerebral neuroendocrine complex, in the stomatogastric nervous system of larvae and adults, and additionally in muscles of the alimentary canal in the adult. The most prominent element of these peripheral processes is a large plexus of varicose fibers located in the wall of the aorta, the main site for the release of neurohormones produced in the brain of blowflies. The presence of Corazonin-immunoreactive material in the aortic plexus suggests that this peptide functions as a neurohormone, During metamorphosis, the immunoreactive neurons found in the thoracic-abdominal ganglion of the larva disappear, and in the brain new immunoreactive neurons are added to those that persist from larval stages. The bulk of the Corazonin-immunoreactive material extracted from adult brains and corpora cardiaca-aorta complexes was found to co-elute with synthetic Corazonin in reversed-phase high-performance liquid chromatography as monitored with enzyme-linked immunosorbent assay. © 1994 Wiley-Liss, Inc.
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isolation and structure of the drosophila Corazonin gene
Biochemical and Biophysical Research Communications, 1994Co-Authors: Jan A VeenstraAbstract:Abstract A recombinant DNA clone containing the Corazonin gene was isolated from a genomic library of Drosophila melanogaster . Its nucleotide sequence predicts a preproCorazonin consisting of an 19 amino acid putative signal peptide, the 11 amino acid Corazonin sequence, a Gly used for amidation, a Lys-Arg proteolytic processing site, and a 39 amino acid Corazonin-precursor-related peptide (CPRP). CPRP has an internal Arg-Arg sequence and thus could possibly be further processed into a tripeptide and a 34-mer. Neither CPRP or its possible products are structurally related to any known neuropeptide, and their physiological function is unknown. The structure of the predicted preproCorazonin is remarkably similar to the preprohormone of adipokinetic hormone, which suggests that Corazonin and adipokinetic hormone have a common evolutionary origin.