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Josiane Girardie - One of the best experts on this subject based on the ideXlab platform.
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detection of vitellogenin in the haemolymph of larval female locusts locusta migratoria treated with the Neurohormone lom omp
Journal of Insect Physiology, 1996Co-Authors: Josiane Girardie, Olivier Richard, Adrein GirardieAbstract:Abstract The ovary maturating parsin of Locusta migratoria (Lom OMP) is a gonadotropic Neurohormone which is active during vitellogenesis over the same period as juvenile hormone (JH). For this reason, a possible vitellogenic effect of the Lom OMP was tested using fifth instar larvae. At this last larval stadium, locusts do not normally produce vitellogenin but the synthesis of vitellogenin can be induced at this time by high doses of JH analogues. Since vitellogenin is rapidly released into the haemolymph, the synthesis of vitellogenin was investigated by detecting the occurrence of vitellogenin in the haemolymph, using SDS-PAGE. The Neurohormone Lom OMP was able to induce vitellogenin synthesis in females but not in males. The maximally efficient dose-range was narrow. The timing of vitellogenin occurrence was delayed as compared to that obtained with JH. The Lom OMP inducibility, evaluated by the number of responsive females, was lower than that obtained with JH provided by the implantation of a single corpus allatum. In allatectomized females, the Lom OMP inducibility was not suppressed but, on the contrary, increased. The gonadotropic activity of the Lom OMP thus acts through a vitellogenic effect similar to the gonadotropic activity of JH but the mode of action of Lom OMP is different to and independent of that of JH.
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immunochemical analysis of the distribution of the new ovary maturating Neurohormone during development of the african locust locusta migratoria
Cell and Tissue Research, 1992Co-Authors: Olivier Richard, Josiane GirardieAbstract:Following our prior identification of a gonadotropic Neurohormone isolated from the neurosecretory lobe of the corpora cardiaca of the African locust, we have raised a polyclonal antiserum against this new molecule. In the present paper, we characterize this antiserum using enzyme-linked immunosorbent assay and Western blotting. The latter procedure reveals that the immune serum specifically recognizes the Neurohormone, which we have termed ‘ovary maturating parsin’. Immunohistochemistry, enzyme-linked immunosorbent assay and Western blotting were used to analyze the distribution of this gonadotropic Neurohormone throughout the central nervous system during development. It is produced only by the type-B neurosecretory cells of the pars intercerebralis-corpora cardiaca system and is present both in males and females throughout life from embryo to adult. This permanent expression suggests that the Neurohormone may have functions other than its primary direct gonadotropic role in females.
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physical characterization and sequence identification of the ovary maturating parsin a new Neurohormone purified from the nervous corpora cardiaca of the african locust locusta migratoria migratorioides
FEBS Journal, 1991Co-Authors: Josiane Girardie, Olivier Richard, Jeanclaude Huet, Claude Nespoulous, Alain Van Dorsselaer, Jeanclaude PernolletAbstract:A novel Neurohormone, which anticipates ovarian maturation, was recently purified using liquid chromatography from the African locust nervous corpora cardiaca. Both its function and production by the pars intercerebralis of Locusta migratoria lead to its name, the ovary maturating parsin (Lom OMP). In this study, the Lom OMP was physically and chemically characterized. Its multiply charged ion spectrum was interpreted as two peaks of quite equal size having molecular masses of 6923.4 Da (major peak) and 6907.3 Da. The Lom OMP presented no periodic secondary structure according to the far ultraviolet circular dichroism spcctrum obtained. It is composed of 65 amino acids and included a high concentration of alanine but is devoid of cysteine, isoleucine, methionine, lysine and threonine. The amino acid sequence indicated only one microheterogeneity, observed at position 26, consisted in the replacement of serine by alanine. The calculated M, of the two acidic isoforms (calculated pHi = 4.87) were found to be in agreement with mass spectrometry measurements. When compared to the sequence libraries, the Lom OMP, the first insect gonadotropic Neurohormone, was revealed as an unique protein.
Olivier Richard - One of the best experts on this subject based on the ideXlab platform.
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detection of vitellogenin in the haemolymph of larval female locusts locusta migratoria treated with the Neurohormone lom omp
Journal of Insect Physiology, 1996Co-Authors: Josiane Girardie, Olivier Richard, Adrein GirardieAbstract:Abstract The ovary maturating parsin of Locusta migratoria (Lom OMP) is a gonadotropic Neurohormone which is active during vitellogenesis over the same period as juvenile hormone (JH). For this reason, a possible vitellogenic effect of the Lom OMP was tested using fifth instar larvae. At this last larval stadium, locusts do not normally produce vitellogenin but the synthesis of vitellogenin can be induced at this time by high doses of JH analogues. Since vitellogenin is rapidly released into the haemolymph, the synthesis of vitellogenin was investigated by detecting the occurrence of vitellogenin in the haemolymph, using SDS-PAGE. The Neurohormone Lom OMP was able to induce vitellogenin synthesis in females but not in males. The maximally efficient dose-range was narrow. The timing of vitellogenin occurrence was delayed as compared to that obtained with JH. The Lom OMP inducibility, evaluated by the number of responsive females, was lower than that obtained with JH provided by the implantation of a single corpus allatum. In allatectomized females, the Lom OMP inducibility was not suppressed but, on the contrary, increased. The gonadotropic activity of the Lom OMP thus acts through a vitellogenic effect similar to the gonadotropic activity of JH but the mode of action of Lom OMP is different to and independent of that of JH.
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immunochemical analysis of the distribution of the new ovary maturating Neurohormone during development of the african locust locusta migratoria
Cell and Tissue Research, 1992Co-Authors: Olivier Richard, Josiane GirardieAbstract:Following our prior identification of a gonadotropic Neurohormone isolated from the neurosecretory lobe of the corpora cardiaca of the African locust, we have raised a polyclonal antiserum against this new molecule. In the present paper, we characterize this antiserum using enzyme-linked immunosorbent assay and Western blotting. The latter procedure reveals that the immune serum specifically recognizes the Neurohormone, which we have termed ‘ovary maturating parsin’. Immunohistochemistry, enzyme-linked immunosorbent assay and Western blotting were used to analyze the distribution of this gonadotropic Neurohormone throughout the central nervous system during development. It is produced only by the type-B neurosecretory cells of the pars intercerebralis-corpora cardiaca system and is present both in males and females throughout life from embryo to adult. This permanent expression suggests that the Neurohormone may have functions other than its primary direct gonadotropic role in females.
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Time-dependent variations in the activity of a novel ovary maturating Neurohormone from the nervous corpora cardiaca during oögenesis in the locust, Locusta migratoria migratorioides
Journal of Insect Physiology, 1992Co-Authors: J. Girardie, Olivier Richard, Adrein GirardieAbstract:Abstract A molecule, which stimulates ovary maturation, was purified completely from the nervous corpora cardiaca of Locusta migratoria migratorioides using only two steps of liquid chromatography separation. A specific polyclonal immune serum directed against the ovary maturating molecule was obtained. It inhibits oogenesis when injected daily into adult females on and after day 1. Injections of the immune serum during oogenesis were used to investigate the time-dependent variations of the activity of the new gonadotropic Neurohormone. The presence of the circulating Neurohormone is not required for previtellogenesis or for choriogenesis. In contrast, the Neurohormone is essential for vitellogenesis. The gonadotropic activity pattern of the Neurohormone is somewhat similar to that of the juvenile hormone. However, the novel Neurohormone does not disturb metamorphosis and pigmentation suggesting that it has no allatotropic activity. Moreover, inhibition of vitellogenesis by binding the circulating Neurohormone with immune serum cannot be compensated for by the implantation of supplementary corpora allata. Thus, the action of the Neurohormone on vitellogenesis is probably not mediated through the corpora allata. The ovary maturating Neurohormone appears to be the gonadotropic juvenile hormone independent factor previously reported by one of us.
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physical characterization and sequence identification of the ovary maturating parsin a new Neurohormone purified from the nervous corpora cardiaca of the african locust locusta migratoria migratorioides
FEBS Journal, 1991Co-Authors: Josiane Girardie, Olivier Richard, Jeanclaude Huet, Claude Nespoulous, Alain Van Dorsselaer, Jeanclaude PernolletAbstract:A novel Neurohormone, which anticipates ovarian maturation, was recently purified using liquid chromatography from the African locust nervous corpora cardiaca. Both its function and production by the pars intercerebralis of Locusta migratoria lead to its name, the ovary maturating parsin (Lom OMP). In this study, the Lom OMP was physically and chemically characterized. Its multiply charged ion spectrum was interpreted as two peaks of quite equal size having molecular masses of 6923.4 Da (major peak) and 6907.3 Da. The Lom OMP presented no periodic secondary structure according to the far ultraviolet circular dichroism spcctrum obtained. It is composed of 65 amino acids and included a high concentration of alanine but is devoid of cysteine, isoleucine, methionine, lysine and threonine. The amino acid sequence indicated only one microheterogeneity, observed at position 26, consisted in the replacement of serine by alanine. The calculated M, of the two acidic isoforms (calculated pHi = 4.87) were found to be in agreement with mass spectrometry measurements. When compared to the sequence libraries, the Lom OMP, the first insect gonadotropic Neurohormone, was revealed as an unique protein.
Jan A Veenstra - One of the best experts on this subject based on the ideXlab platform.
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most lepidopteran neuroparsin genes seem functional but in some domesticated silkworm strains it has a fatal mutation
General and Comparative Endocrinology, 2020Co-Authors: Jan A VeenstraAbstract:Abstract The primary sequence of the Arthropod Neurohormone neuroparsin is so variable that so far no orthologs from moths and butterflies have been characterized, even though classical neurosecretory stains identify cells that are homologous to those producing this hormone in other insect species. Here Lepidopteran cDNAs showing limited sequence similarity to other insect neuroparsins are described. That these cDNAs do indeed code for authentic neuroparsins was confirmed by in situ hybridization in the wax moth, Galleria mellonella, which labeled the neuroparsin neuroendocrine cells. Although in virtually all genome assemblies from Lepidoptera a neuroparsin gene could be identified, the genome assembly from the silkworm, Bombyx mori, has a neuroparsin gene containing a 16 nucleotide deletion that renders this gene nonfunctional. Although only a small number of all silkworm strains carry this deletion, it suggests that the domestication of the silkworm has rendered the function of this Neurohormone dispensable.
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The contribution of the genomes of a termite and a locust to our understanding of insect neuropeptides and Neurohormones
Frontiers in physiology, 2014Co-Authors: Jan A VeenstraAbstract:The genomes of the migratory locust Locusta migratoria and the termite Zootermopsis nevadensis were mined for genes encoding neuropeptides, Neurohormones and their G-protein coupled receptors (GPCRs). Both species have retained a larger number of neuropeptide and neuropeptide GPCRs than the better known holometabolous insect species, while other genes that in holometabolous species appear to have a single transcript produce two different precursors in the locust, the termite or both. Thus the recently discovered CNMa neuropeptide gene has two transcripts predicted to produce two structurally different CNMa peptides in the termite, while the locust produces two different myosuppressin peptides in the same fashion. Both these species also have a calcitonin gene, which is different from the gene encoding the calcitonin-like insect diuretic hormone. This gene produces two types of calcitonins, calcitonins A and B. It is also present in Lepidoptera and Coleoptera and some Diptera, but absent from mosquitoes and Drosophila. However, in holometabolous insect species, only the B transcript is produced. Their putative receptors were also identified. In contrast, Locusta has a highly unusual gene that codes for a salivation stimulatory peptide. The Locusta genes for neuroparsin and vasopressin are particularly interesting. The neuroparsin gene produces five different transcripts, of which only one codes for the Neurohormone identified from the corpora cardiaca. The other four transcripts code for neuroparsin-like proteins, which lack four amino acid residues, and that for that reason we called neoneuroparsins. The number of transcripts for the neoneuroparsins is about two hundred times larger than the number of neuroparsin transcripts. The first exon and the putative promoter of the vasopressin genes, of which there are about seven copies in the genome, is very well conserved, but the remainder of these genes is not. The relevance of these findings is discussed.
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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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neuropeptide and Neurohormone precursors in the pea aphid acyrthosiphon pisum
Insect Molecular Biology, 2010Co-Authors: Jurgen Huybrechts, Joel Bonhomme, Sara Minoli, Nathalie Prunierleterme, Alain Robichon, Jan A Veenstra, Aviv Dombrovsky, Mohatmed Abdellatief, Denis TaguAbstract:Aphids respond to environmental changes by developing alternative phenotypes with differing reproductive modes. Parthenogenetic reproduction occurs in spring and summer, whereas decreasing day lengths in autumn provoke the production of sexual forms. Changing environmental signals are relayed by brain neuroendocrine signals to the ovarioles. We combined bioinformatic analyses with brain peptidomics and cDNA analyses to establish a catalogue of pea aphid neuropeptides and Neurohormones. 42 genes encoding neuropeptides and Neurohormones were identified, of which several were supported by expressed sequence tags and/or peptide mass analyses. Interesting features of the pea aphid peptidome are the absence of genes coding for corazonin, vasopressin and sulfakinin and the presence of 10 different genes coding insulin related peptides, one of which appears to be very abundantly expressed.
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ovary maturing parsin and diuretic hormone are produced by the same neuroendocrine cells in the migratory locust locusta migratoria
Peptides, 2000Co-Authors: Mireille Tamarelle, Geoffrey M Coast, Jan A VeenstraAbstract:In the migratory locust, the CRF-related diuretic hormone that stimulates fluid secretion by the Malpighian tubules, and the ovary maturing parsin, a Neurohormone able to stimulate oogenesis, are produced by the same neuroendocrine cells of the pars intercerebralis in the brain.
Kazuyoshi Tsutsui - One of the best experts on this subject based on the ideXlab platform.
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gonadotropin inhibitory hormone gnih a new key Neurohormone controlling reproductive physiology and behavior
Frontiers in Neuroendocrinology, 2021Co-Authors: Kazuyoshi Tsutsui, Takayoshi UbukaAbstract:The discovery of novel Neurohormones is important for the advancement of neuroendocrinology. In early 1970s, gonadotropin-releasing hormone (GnRH), a hypothalamic neuropeptide that promotes gonadotropin release, was identified to be an endogenous Neurohormone in mammals. In 2000, thirty years later, another hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH), that inhibits gonadotropin release, was found in quail. GnIH acts via GPR147 and inhibits gonadotropin release and synthesis and reproductive function in birds through actions on GnRH neurons in the hypothalamus and pituitary gonadotrophs. Later, GnIH was found in other vertebrates including humans. GnIH studies have advanced the progress of reproductive neuroendocrinology. Furthermore, recent GnIH studies have indicated that abnormal changes in GnIH expression may cause pubertal disorder and reproductive dysfunction. Here, we describe GnIH discovery and its impact on the progress of reproductive neuroendocrinology. This review also highlights advancement and perspective of GnIH studies on drug development for pubertal disorder and reproductive dysfunction. (149/150).
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a new key Neurohormone controlling reproduction gonadotropin inhibitory hormone gnih biosynthesis mode of action and functional significance
Progress in Neurobiology, 2009Co-Authors: Kazuyoshi TsutsuiAbstract:Identification of novel Neurohormones that play important roles in the regulation of pituitary function is essential for the progress of neurobiology. The decapeptide gonadotropin-releasing hormone (GnRH) is the primary factor responsible for the hypothalamic control of gonadotropin secretion. Gonadal sex steroids and inhibin inhibit gonadotropin secretion via feedback from the gonads, but a neuropeptide inhibitor of gonadotropin secretion was, until recently, unknown in vertebrates. In 2000, a novel hypothalamic dodecapeptide that inhibits gonadotropin release was identified in quail and termed gonadotropin-inhibitory hormone (GnIH). This was the first demonstration of a hypothalamic neuropeptide inhibiting gonadotropin release in any vertebrate. GnIH acts on the pituitary and GnRH neurons in the hypothalamus via a novel G protein-coupled receptor for GnIH to inhibit gonadal development and maintenance by decreasing gonadotropin release and synthesis. GnIH neurons express the melatonin receptor and melatonin stimulates the expression of GnIH. Because GnIH exists and functions in several avian species, GnIH is considered to be a new key Neurohormone controlling avian reproduction. From a broader perspective, subsequently the presence of GnIH homologous peptides has been demonstrated in other vertebrates. Mammalian GnIH homologous peptides also act to inhibit reproduction by decreasing gonadotropin release in several mammalian species. Thus, the discovery of GnIH has opened the door to a new research field in reproductive neurobiology. This review summarizes the advances made in our understanding of the biosynthesis, mode of action and functional significance of GnIH, a newly discovered key Neurohormone, and its homologous peptides.
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a new key Neurohormone controlling reproduction gonadotrophin inhibitory hormone in birds discovery progress and prospects
Journal of Neuroendocrinology, 2009Co-Authors: Kazuyoshi Tsutsui, Takayoshi Ubuka, Etsuko Saigoh, Hong Yin, Vishwajit S Chowdhury, Tomohiro Osugi, Kazuyoshi UkenaAbstract:In vertebrates, the neuropeptide control of gonadotrophin secretion is primarily through the stimulatory action of the hypothalamic decapeptide, gonadotrophin-releasing hormone (GnRH). Gonadal sex steroids and inhibin inhibit gonadotrophin secretion via feedback from the gonads, but a hypothalamic neuropeptide inhibiting gonadotrophin secretion was, until recently, unknown in vertebrates. In 2000, we discovered a novel hypothalamic dodecapeptide that directly inhibits gonadotrophin release in quail and termed it gonadotrophin-inhibitory hormone (GnIH). GnIH acts on the pituitary and GnRH neurones in the hypothalamus via a novel G-protein-coupled receptor for GnIH to inhibit gonadal development and maintenance by decreasing gonadotrophin release and synthesis. The pineal hormone melatonin is a key factor controlling GnIH neural function. GnIH occurs in the hypothalamus of several avian species and is considered to be a new key Neurohormone inhibiting avian reproduction. Thus, the discovery of GnIH provides novel directions to investigate neuropeptide regulation of reproduction. This review summarises the discovery, progress and prospects of GnIH, a new key Neurohormone controlling reproduction.
Adrein Girardie - One of the best experts on this subject based on the ideXlab platform.
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detection of vitellogenin in the haemolymph of larval female locusts locusta migratoria treated with the Neurohormone lom omp
Journal of Insect Physiology, 1996Co-Authors: Josiane Girardie, Olivier Richard, Adrein GirardieAbstract:Abstract The ovary maturating parsin of Locusta migratoria (Lom OMP) is a gonadotropic Neurohormone which is active during vitellogenesis over the same period as juvenile hormone (JH). For this reason, a possible vitellogenic effect of the Lom OMP was tested using fifth instar larvae. At this last larval stadium, locusts do not normally produce vitellogenin but the synthesis of vitellogenin can be induced at this time by high doses of JH analogues. Since vitellogenin is rapidly released into the haemolymph, the synthesis of vitellogenin was investigated by detecting the occurrence of vitellogenin in the haemolymph, using SDS-PAGE. The Neurohormone Lom OMP was able to induce vitellogenin synthesis in females but not in males. The maximally efficient dose-range was narrow. The timing of vitellogenin occurrence was delayed as compared to that obtained with JH. The Lom OMP inducibility, evaluated by the number of responsive females, was lower than that obtained with JH provided by the implantation of a single corpus allatum. In allatectomized females, the Lom OMP inducibility was not suppressed but, on the contrary, increased. The gonadotropic activity of the Lom OMP thus acts through a vitellogenic effect similar to the gonadotropic activity of JH but the mode of action of Lom OMP is different to and independent of that of JH.
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Time-dependent variations in the activity of a novel ovary maturating Neurohormone from the nervous corpora cardiaca during oögenesis in the locust, Locusta migratoria migratorioides
Journal of Insect Physiology, 1992Co-Authors: J. Girardie, Olivier Richard, Adrein GirardieAbstract:Abstract A molecule, which stimulates ovary maturation, was purified completely from the nervous corpora cardiaca of Locusta migratoria migratorioides using only two steps of liquid chromatography separation. A specific polyclonal immune serum directed against the ovary maturating molecule was obtained. It inhibits oogenesis when injected daily into adult females on and after day 1. Injections of the immune serum during oogenesis were used to investigate the time-dependent variations of the activity of the new gonadotropic Neurohormone. The presence of the circulating Neurohormone is not required for previtellogenesis or for choriogenesis. In contrast, the Neurohormone is essential for vitellogenesis. The gonadotropic activity pattern of the Neurohormone is somewhat similar to that of the juvenile hormone. However, the novel Neurohormone does not disturb metamorphosis and pigmentation suggesting that it has no allatotropic activity. Moreover, inhibition of vitellogenesis by binding the circulating Neurohormone with immune serum cannot be compensated for by the implantation of supplementary corpora allata. Thus, the action of the Neurohormone on vitellogenesis is probably not mediated through the corpora allata. The ovary maturating Neurohormone appears to be the gonadotropic juvenile hormone independent factor previously reported by one of us.