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Neil Audsley - One of the best experts on this subject based on the ideXlab platform.
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characterisation and tissue distribution of the piscf allatostatin receptor in the red flour beetle tribolium castaneum
Insect Biochemistry and Molecular Biology, 2013Co-Authors: Neil Audsley, Kristel Vuerinckx, Robert J Weaver, Hans Peter Vandersmissen, Paulina Dani, June Matthews, Rachel E Down, Youngjoon Kim, Jozef Vanden BroeckAbstract:Abstract The insect PISCF/allatostatins (ASTs) are pleiotropic peptides that are involved in the regulation of juvenile hormone biosynthesis, are myoinhibitory on the gut and the heart, and suppress feeding in various insects, but their roles in beetles are poorly understood. To provide further insight into the significance of PISCF/ASTs in beetles, the PISCF/AST receptor from Tribolium castaneum has been characterised and its tissue distribution determined. The biological activity of the T. castaneum PISCF/AST (Trica-AS) was also investigated. The Trica-AS receptor shows high sequence homology to other insect PISCF/AST receptors, which are related to the mammalian somatostatin/opioid receptors, a family of G protein-coupled receptors. The Trica-AS receptor was activated in a dose-dependent manner by both Trica-AS and T. castaneum allatostatin double C (Trica-ASTCC) as well as Manduca sexta -allatostatin (Manse-AS). Other allatoregulatory peptides (a FLG/AST, a MIP/AST and an Allatotropin) and somatostatin 14 were inactive on this receptor. Receptor transcript levels in tissues, determined by qRT-PCR, were highest in the head and the gut, with variable amounts in the fat body and reproductive organs. There were measurable differences in receptor levels of the head, fat body and reproductive organs between males and females. There was also a widespread distribution of Trica-AS in various tissues of T. castaneum . The Trica-AS peptide precursor was most abundant in the head and there was a significant difference between levels in the heads and reproductive organs of males and females. Whole mount immunocytochemistry localised Trica-AS in the median and lateral neurosecretory cells of the brain, in the corpus cardiacum and throughout the ventral nerve cord. The peptide was also present in midgut neurosecretory cells, but no immunostaining was detected in the reproductive organs or Malpighian tubules. The widespread distribution of both Trica-AS and its receptor suggest this peptide may have multiple roles in beetles. However, Trica-AS had no effect on the spontaneous contractions of the gut or ovaries of T. castaneum but this peptide did stimulate the release of proteases from the anterior midgut of another beetle, Tenebrio molitor . The activation of the Trica-AS receptor by Trica-ASTCC implies a physiological role for this peptide in beetles, which remains to be identified.
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neuropeptide regulators of juvenile hormone synthesis structures functions distribution and unanswered questions
Annals of the New York Academy of Sciences, 2009Co-Authors: Robert J Weaver, Neil AudsleyAbstract:Juvenile hormones (JH), produced by the corpora allata, have an essential role in growth and development, morphogenesis, and reproductive processes of insects. The output of JH and circulating titer are required to be precisely regulated throughout the insect's life in response to developmental requirements and environmental factors. The synthesis of JH must be periodically turned off and on, or finely tuned, in a highly coordinated way. Except for a few key or intensely studied insect species, the control of synthesis of JH by regulatory peptides remains largely undefined and many of the details remain obscure. Several different classes of neuropeptide are believed to be involved in the regulation of corpus allatum function and hence JH output. In different insect species and at different stages of development, these regulatory peptides may include at least three types of inhibitory allatostatins, at least one type of stimulatory Allatotropin, and perhaps several other, as yet largely undefined, additional neuropeptides. The details of how each of these peptides acts to affect JH production and their relationship to each other in the coordination of JH synthesis remain to be established. There are several insect orders for which almost nothing is known concerning the regulation of JH synthesis and the peptides that might be involved. Current proteomic and genomic studies are helping to redress this balance but at the same time posing new questions. Other neuropeptides are implicated in the regulation of JH production, and there is new evidence concerning the mode of action of Allatotropins.
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neuropeptides of the beetle tenebrio molitor identified using maldi tof mass spectrometry and deduced sequences from the tribolium castaneum genome
Peptides, 2008Co-Authors: Robert J Weaver, Neil AudsleyAbstract:Abstract Four neuropeptides were identified from the brain and corpora cardiaca-corpora allata (CC-CA) of the mealworm beetle Tenebrio molitor using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and information derived from the genome of the red flour beetle, Tribolium castaneum . Leucomyosuppressin (a FLRFamide), previously associated with cockroaches, but also subsequently identified from honey bee seen as a prominent peptide in both brain and CC-CA of T.molitor . A coding sequence for this peptide is found in the genome of T. castaneum. In addition, three FXPRLamides (pyrokinins), provisionally Tenmo-PK-1, Tenmo-PK-2 and Tenmo-PK-3 (HVVNFTPRLamide, SPPFAPRLamide, HL(I)SPFSPRLamide) were identified in both CC-CA and brain of T. molitor , again on the basis of predicted occurrence or similarity in T. castaneum . The sequence of Tenmo-PK-2 is the same as the PK-2 of the cockroach, Periplaneta americana . Other peptides readily predicted from the genome of T. castaneum include two AKH/HrTH peptides (Trica-AKH-1; pELNFSTDWamide and Trica-AKH-2; pELNFTPNWamide), the second of which is identical to Pyrap-AKH, an AKH-related peptide (Trica AKH-L; pEVTFSRDWPamide), two CRF-related diuretic factors (Trica-DH 37 and Trica-DH 47 ), the latter identical to Tenmo-DH 47 , a putative antidiuretic factor (Trica-ADFb; LYDDGSYKPHVYGF-OH), two sulfakinin-like peptides (Trica-SK-1; pETSDDY(SO 3 )GHLRFamide, and Trica SK-2; GEEPFDDYGHMRFamide), a potential allatostatin-C (Trica-AS; pESRYRQCYFNPISCF-OH), six allatostatin-B/myoinhibitory peptides (Trica-AST-B-1,2,3,4,5 & 6; DWNKDLHIWamide, GWNNLHEGWamide, AWQSLQSGWamide, NWGQFHGGWamide, SKWDNFRGSWamide, EPAWSNLGIWamide), an Allatotropin-like peptide (Trica-ATL; GIEALKYHNMDLGTARGYamide), four ‘CAPA’-related peptides (Trica-CAPA-1,2,3,4; NKLASVYALTPSLRVamide, RIGKMVSFPRIamide, PGANSGGMWFGPRLamide, SENFTPWAYIILNGEAPIIREVHYSPRLamide), proctolin (RYLPT), a potential SIFamide (Trica-SIFa; TYRKPPFNGSIFamide), an arginine-vasopressin-related peptide (Trica-AVP; CLITNCPRGamide) and an ITP-related peptide (Trica-ITP). No evidence was found for the presence of ‘A’ allatostatins (Y/FxFGLamides) or corazonin, either in T. molitor , or in the genome of T. castaneum .
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allatostatins and Allatotropin in the corpus cardiacum corpus allatum complex of larval and adult lepidopterans studied by confocal laser scanning microscopy correlation to juvenile hormone biosynthesis
Cell and Tissue Research, 2003Co-Authors: Hanne Duve, Neil Audsley, Rob Weaver, Alan ThorpeAbstract:Peptidergic innervation of the corpus cardiacum/corpus allatum (CC/CA) retrocerebral complex, and neurosecretory areas of the brain of the lepidopterans Lacanobia oleracea, Heliothis virescens and Manduca sexta was studied by immunocytochemistry linked to confocal laser scanning microscopy. The patterns of immunostaining resulting from the simultaneous application of fluorochrome-conjugated antibodies against Manduca sexta allatostatin (Mas-AS), M. sexta Allatotropin (Mas-AT), and a representative of the −Y/FXFGL-NH2 superfamily of allatostatins was correlated with the physiological effects of these putative allatoregulatory peptides on juvenile hormone (JH) biosynthesis by the corpora allata. Whereas the two types of allatostatin immunoreactivity are present in both larval and adult CA of the three species, Allatotropin immunoreactivity occurs only in the adult gland. The conclusion that withdrawal of the stimulatory effect of Allatotropin is unlikely to be involved in the downregulation of CA activity prior to the onset of metamorphosis, but that an inhibitory influence of at least Mas-AS is important, is borne out in physiological experiments on JH biosynthesis in M. sexta larvae (Mas-AS inhibitory, Mas-AT without effect). Immunoreactivity to the Y/FXFGL-NH2 allatostatins is present in both larval and adult CA and CC, frequently co-localised with Mas-AS. The function of this peptide family in the retrocerebral complex remains enigmatic since experiments on JH biosynthesis, either when the peptide is administered alone, or together with Mas-AS, show no effect on JH biosynthesis.
Jorge Rafael Ronderos - One of the best experts on this subject based on the ideXlab platform.
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Allatotropin modulates myostimulatory and cardioacceleratory activities in rhodnius prolixus stal
PLOS ONE, 2015Co-Authors: Maria Jose Villalobossambucaro, Fernando G. Noriega, Alicia Nieves Lorenzofigueiras, F L Riccillo, L Diambra, Jorge Rafael RonderosAbstract:Haematophagous insects can ingest large quantities of blood in a single meal and eliminate high volumes of urine in the next few hours. This rise in diuresis is possible because the excretory activity of the Malpighian tubules is facilitated by an increase in haemolymph circulation as a result of intensification of aorta contractions combined with an increase of the anterior midgut peristaltic waves. It has been previously described that haemolymph circulation during post-prandial diuresis is stimulated by the synergistic activity of Allatotropin (AT) and serotonin in the kissing bug Triatoma infestans; resulting in an increase in aorta contractions. In the same species, AT stimulates anterior midgut and rectum muscle contractions to mix urine and feces and facilitate the voiding of the rectum. Furthermore, levels of AT in midgut and Malpighian tubules increased in the afternoon when insects are getting ready for nocturnal feeding. In the present study we describe the synergistic effect of AT and serotonin increasing the frequency of contractions of the aorta in Rhodnius prolixus. The basal frequency of contractions of the aorta in the afternoon is higher that the observed during the morning, suggesting the existence of a daily rhythmic activity. The AT receptor is expressed in the rectum, midgut and dorsal vessel, three critical organs involved in post-prandial diuresis. All together these findings provide evidence that AT plays a role as a myoregulatory and cardioacceleratory peptide in R. prolixus.
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expression of a neuropeptide similar to Allatotropin in free living turbellaria platyhelminthes
Tissue & Cell, 2011Co-Authors: Mariana Laura Adami, Cristina Damborenea, Jorge Rafael RonderosAbstract:Abstract Mechanisms coordinating cell–cell interaction have appeared early in evolution. Allatotropin (AT), a neuropeptide isolated based on its ability to stimulate the synthesis of juvenile hormones (JHs) in insects has also been found in other invertebrate phyla. Despite this function, AT has proved to be myotropic. In the present study we analyze its expression in two groups of Turbellaria (Catenulida, Macrostomida), and its probable relationship with muscle tissue. The results show the presence of an AT-like peptide in the free living turbellaria analyzed. The analysis of the expression of the peptide together with phalloidin, suggests a functional relationship between the peptide and muscle tissue, showing that it could be acting as a myoregulator. The finding of immunoreactive fibers associated with sensory organs like ciliated pits in Catenulida and eyes in Macrostomida makes probable that AT could play a role in the physiological mechanisms controlling circadian activities. Furthermore, the existence of AT in several phyla of Protostomata suggests that this peptide could be a synapomorphic feature of this group. Indeed, the presence in organisms that do not undergo metamorphosis, could be signaling that it was first involved in myotropic activities, being the stimulation of the synthesis of JHs a secondary function acquired by the phylum Arthropoda.
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Allatotropin like peptide in malpighian tubules insect renal tubules as an autonomous endocrine organ
General and Comparative Endocrinology, 2009Co-Authors: Maria Soledad Santini, Jorge Rafael RonderosAbstract:Malpighian tubules (MTs) are recognised as the main excretory organ in insects, ensuring water and mineral balance. Haematophagous insects incorporate with each meal a large quantity of blood, producing a particularly large volume of urine in a few hours. In the present study, we report the presence of an Allatotropin-like (AT-like) peptide in MTs of Triatoma infestans (Klug). The AT-like content in MTs decreased during the first hours after blood-intake, correlating with the post-prandial diuresis. In vivo artificial dilution of haemolymph showed a similar effect. Isolated MTs challenged with a diluted saline solution resulted in an autonomous and reversible response of the organ regulating the quantity of peptide released to the medium, and suggesting that MTs synthesise the AT-like peptide. While MTs are recognised as the target for several hormones, our results corroborate that they also have the ability to produce and secrete a hormone in an autonomous way.
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Allatotropin like peptide released by malpighian tubules induces hindgut activity associated with diuresis in the chagas disease vector triatoma infestans klug
The Journal of Experimental Biology, 2007Co-Authors: Maria Soledad Santini, Jorge Rafael RonderosAbstract:Haematophagous insects incorporate a large amount of blood with each meal, producing a big quantity of urine in a few hours to eliminate the excess water and Na(+). Malpighian tubules (MTs) have traditionally been seen as a system that responds to neuroendocrine stimulus. In a related paper, we demonstrated that MTs of Triatoma infestans produce an autonomous endocrine secretion of an Allatotropin-like (AT-like) peptide. In the present study, we report a myostimulatory activity of AT at the level of the hindgut (HG), associated with endocrine mechanisms regulating post-prandial diuresis. Allatotropin induced an increase in frequency and intensity of peristaltic contractions at the level of the HG. The release of the HG content in MTs-HG in vitro preparations undergoing an osmotic shock occurred at different times, depending on the number of MTs present, and there was no release in treatments without MTs. The application of an AT-antiserum to MTs-HG preparations undergoing osmotic shock produced a delay or a long-term blockade of diuresis, depending on the antiserum dilution applied. Similar results were obtained when AT-antiserum was applied in vivo prior to blood intake, decreasing the volume of urine eliminated during the first 2 h. Our results allow us to assign a specific endocrine function to the AT-like peptide released by MTs that is linked to the elimination of urine after blood meals.
Jozef Vanden Broeck - One of the best experts on this subject based on the ideXlab platform.
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molecular cloning and characterization of the Allatotropin precursor and receptor in the desert locust schistocerca gregaria
Frontiers in Neuroscience, 2015Co-Authors: Els Lismont, Stephen S Tobe, Rut Vleugels, Elisabeth Marchal, Liesbeth Badisco, Pieter Van Wielendaele, Cynthia Lenaerts, Sven Zels, Jozef Vanden BroeckAbstract:Allatotropins (ATs) are pleiotropic neuropeptides initially isolated from the tobacco hornworm, Manduca sexta. In 2008, the first receptor for AT-like peptides (ATR) was characterized in Bombyx mori. Since then, ATRs have also been characterized in M. sexta, Tribolium castaneum, Aedes aegypti and Bombus terrestris. These receptors show sequence similarity to vertebrate orexin (ORX) receptors. When generating an EST-database of the desert locust (Schistocerca gregaria) central nervous system, we found cDNA sequences encoding the Schgr-AT precursor and a fragment of its putative receptor. This receptor cDNA has now been completed and functionally expressed in mammalian cell lines. Activation of this receptor, designated as Schgr-ATR, by Schgr-AT caused an increase in intracellular calcium ions, as well as cyclic AMP (cAMP), with an EC50 value in the nanomolar range. In addition, the transcript distribution of both the Schgr-AT precursor and Schgr-ATR was investigated by means of quantitative real-time PCR. Moreover, we found more evidence for the myotropic and allatostimulatory actions of Schgr-AT in the desert locust. These data are discussed and situated in a broader context by comparison with literature data on AT and ATR in insects.
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characterisation and tissue distribution of the piscf allatostatin receptor in the red flour beetle tribolium castaneum
Insect Biochemistry and Molecular Biology, 2013Co-Authors: Neil Audsley, Kristel Vuerinckx, Robert J Weaver, Hans Peter Vandersmissen, Paulina Dani, June Matthews, Rachel E Down, Youngjoon Kim, Jozef Vanden BroeckAbstract:Abstract The insect PISCF/allatostatins (ASTs) are pleiotropic peptides that are involved in the regulation of juvenile hormone biosynthesis, are myoinhibitory on the gut and the heart, and suppress feeding in various insects, but their roles in beetles are poorly understood. To provide further insight into the significance of PISCF/ASTs in beetles, the PISCF/AST receptor from Tribolium castaneum has been characterised and its tissue distribution determined. The biological activity of the T. castaneum PISCF/AST (Trica-AS) was also investigated. The Trica-AS receptor shows high sequence homology to other insect PISCF/AST receptors, which are related to the mammalian somatostatin/opioid receptors, a family of G protein-coupled receptors. The Trica-AS receptor was activated in a dose-dependent manner by both Trica-AS and T. castaneum allatostatin double C (Trica-ASTCC) as well as Manduca sexta -allatostatin (Manse-AS). Other allatoregulatory peptides (a FLG/AST, a MIP/AST and an Allatotropin) and somatostatin 14 were inactive on this receptor. Receptor transcript levels in tissues, determined by qRT-PCR, were highest in the head and the gut, with variable amounts in the fat body and reproductive organs. There were measurable differences in receptor levels of the head, fat body and reproductive organs between males and females. There was also a widespread distribution of Trica-AS in various tissues of T. castaneum . The Trica-AS peptide precursor was most abundant in the head and there was a significant difference between levels in the heads and reproductive organs of males and females. Whole mount immunocytochemistry localised Trica-AS in the median and lateral neurosecretory cells of the brain, in the corpus cardiacum and throughout the ventral nerve cord. The peptide was also present in midgut neurosecretory cells, but no immunostaining was detected in the reproductive organs or Malpighian tubules. The widespread distribution of both Trica-AS and its receptor suggest this peptide may have multiple roles in beetles. However, Trica-AS had no effect on the spontaneous contractions of the gut or ovaries of T. castaneum but this peptide did stimulate the release of proteases from the anterior midgut of another beetle, Tenebrio molitor . The activation of the Trica-AS receptor by Trica-ASTCC implies a physiological role for this peptide in beetles, which remains to be identified.
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isolation and functional characterization of an Allatotropin receptor from manduca sexta
Insect Biochemistry and Molecular Biology, 2011Co-Authors: Frank M Horodyski, Heleen Verlinden, Nanda Filkin, Hans Peter Vandersmissen, Christophe Fleury, Stuart E Reynolds, Zhenpeng Kai, Jozef Vanden BroeckAbstract:Manduca sexta Allatotropin (Manse-AT) is a multifunctional neuropeptide whose actions include the stimulation of juvenile hormone biosynthesis, myotropic stimulation, cardioacceleratory functions, and inhibition of active ion transport. Manse-AT is a member of a structurally related peptide family that is widely found in insects and also in other invertebrates. Its precise role depends on the insect species and developmental stage. In some lepidopteran insects including M. sexta, structurally-related AT-like (ATL) peptides can be derived from alternatively spliced mRNAs transcribed from the AT gene. We have isolated a cDNA for an AT receptor (ATR) from M. sexta by a PCR-based approach using the sequence of the ATR from Bombyx mori. The sequence of the M. sexta ATR is similar to several G protein-coupled receptors from other insect species and to the mammalian orexin receptor. We demonstrate that the M. sexta ATR expressed in vertebrate cell lines is activated in a dose-responsive manner by Manse-AT and each Manse-ATL peptide in the rank order ATL-I > ATL-II > ATL-III > AT, and functional analysis in multiple cell lines suggest that the receptor is coupled through elevated levels of Ca(2+) and cAMP. In feeding larvae, Manse-ATR mRNA is present at highest levels in the Malpighian tubules, followed by the midgut, hindgut, testes, and corpora allata, consistent with its action on multiple target tissues. In the adult corpora cardiaca--corpora allata complex, Manse-ATR mRNA is present at relatively low levels in both sexes.
Robert J Weaver - One of the best experts on this subject based on the ideXlab platform.
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characterisation and tissue distribution of the piscf allatostatin receptor in the red flour beetle tribolium castaneum
Insect Biochemistry and Molecular Biology, 2013Co-Authors: Neil Audsley, Kristel Vuerinckx, Robert J Weaver, Hans Peter Vandersmissen, Paulina Dani, June Matthews, Rachel E Down, Youngjoon Kim, Jozef Vanden BroeckAbstract:Abstract The insect PISCF/allatostatins (ASTs) are pleiotropic peptides that are involved in the regulation of juvenile hormone biosynthesis, are myoinhibitory on the gut and the heart, and suppress feeding in various insects, but their roles in beetles are poorly understood. To provide further insight into the significance of PISCF/ASTs in beetles, the PISCF/AST receptor from Tribolium castaneum has been characterised and its tissue distribution determined. The biological activity of the T. castaneum PISCF/AST (Trica-AS) was also investigated. The Trica-AS receptor shows high sequence homology to other insect PISCF/AST receptors, which are related to the mammalian somatostatin/opioid receptors, a family of G protein-coupled receptors. The Trica-AS receptor was activated in a dose-dependent manner by both Trica-AS and T. castaneum allatostatin double C (Trica-ASTCC) as well as Manduca sexta -allatostatin (Manse-AS). Other allatoregulatory peptides (a FLG/AST, a MIP/AST and an Allatotropin) and somatostatin 14 were inactive on this receptor. Receptor transcript levels in tissues, determined by qRT-PCR, were highest in the head and the gut, with variable amounts in the fat body and reproductive organs. There were measurable differences in receptor levels of the head, fat body and reproductive organs between males and females. There was also a widespread distribution of Trica-AS in various tissues of T. castaneum . The Trica-AS peptide precursor was most abundant in the head and there was a significant difference between levels in the heads and reproductive organs of males and females. Whole mount immunocytochemistry localised Trica-AS in the median and lateral neurosecretory cells of the brain, in the corpus cardiacum and throughout the ventral nerve cord. The peptide was also present in midgut neurosecretory cells, but no immunostaining was detected in the reproductive organs or Malpighian tubules. The widespread distribution of both Trica-AS and its receptor suggest this peptide may have multiple roles in beetles. However, Trica-AS had no effect on the spontaneous contractions of the gut or ovaries of T. castaneum but this peptide did stimulate the release of proteases from the anterior midgut of another beetle, Tenebrio molitor . The activation of the Trica-AS receptor by Trica-ASTCC implies a physiological role for this peptide in beetles, which remains to be identified.
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neuropeptide regulators of juvenile hormone synthesis structures functions distribution and unanswered questions
Annals of the New York Academy of Sciences, 2009Co-Authors: Robert J Weaver, Neil AudsleyAbstract:Juvenile hormones (JH), produced by the corpora allata, have an essential role in growth and development, morphogenesis, and reproductive processes of insects. The output of JH and circulating titer are required to be precisely regulated throughout the insect's life in response to developmental requirements and environmental factors. The synthesis of JH must be periodically turned off and on, or finely tuned, in a highly coordinated way. Except for a few key or intensely studied insect species, the control of synthesis of JH by regulatory peptides remains largely undefined and many of the details remain obscure. Several different classes of neuropeptide are believed to be involved in the regulation of corpus allatum function and hence JH output. In different insect species and at different stages of development, these regulatory peptides may include at least three types of inhibitory allatostatins, at least one type of stimulatory Allatotropin, and perhaps several other, as yet largely undefined, additional neuropeptides. The details of how each of these peptides acts to affect JH production and their relationship to each other in the coordination of JH synthesis remain to be established. There are several insect orders for which almost nothing is known concerning the regulation of JH synthesis and the peptides that might be involved. Current proteomic and genomic studies are helping to redress this balance but at the same time posing new questions. Other neuropeptides are implicated in the regulation of JH production, and there is new evidence concerning the mode of action of Allatotropins.
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neuropeptides of the beetle tenebrio molitor identified using maldi tof mass spectrometry and deduced sequences from the tribolium castaneum genome
Peptides, 2008Co-Authors: Robert J Weaver, Neil AudsleyAbstract:Abstract Four neuropeptides were identified from the brain and corpora cardiaca-corpora allata (CC-CA) of the mealworm beetle Tenebrio molitor using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and information derived from the genome of the red flour beetle, Tribolium castaneum . Leucomyosuppressin (a FLRFamide), previously associated with cockroaches, but also subsequently identified from honey bee seen as a prominent peptide in both brain and CC-CA of T.molitor . A coding sequence for this peptide is found in the genome of T. castaneum. In addition, three FXPRLamides (pyrokinins), provisionally Tenmo-PK-1, Tenmo-PK-2 and Tenmo-PK-3 (HVVNFTPRLamide, SPPFAPRLamide, HL(I)SPFSPRLamide) were identified in both CC-CA and brain of T. molitor , again on the basis of predicted occurrence or similarity in T. castaneum . The sequence of Tenmo-PK-2 is the same as the PK-2 of the cockroach, Periplaneta americana . Other peptides readily predicted from the genome of T. castaneum include two AKH/HrTH peptides (Trica-AKH-1; pELNFSTDWamide and Trica-AKH-2; pELNFTPNWamide), the second of which is identical to Pyrap-AKH, an AKH-related peptide (Trica AKH-L; pEVTFSRDWPamide), two CRF-related diuretic factors (Trica-DH 37 and Trica-DH 47 ), the latter identical to Tenmo-DH 47 , a putative antidiuretic factor (Trica-ADFb; LYDDGSYKPHVYGF-OH), two sulfakinin-like peptides (Trica-SK-1; pETSDDY(SO 3 )GHLRFamide, and Trica SK-2; GEEPFDDYGHMRFamide), a potential allatostatin-C (Trica-AS; pESRYRQCYFNPISCF-OH), six allatostatin-B/myoinhibitory peptides (Trica-AST-B-1,2,3,4,5 & 6; DWNKDLHIWamide, GWNNLHEGWamide, AWQSLQSGWamide, NWGQFHGGWamide, SKWDNFRGSWamide, EPAWSNLGIWamide), an Allatotropin-like peptide (Trica-ATL; GIEALKYHNMDLGTARGYamide), four ‘CAPA’-related peptides (Trica-CAPA-1,2,3,4; NKLASVYALTPSLRVamide, RIGKMVSFPRIamide, PGANSGGMWFGPRLamide, SENFTPWAYIILNGEAPIIREVHYSPRLamide), proctolin (RYLPT), a potential SIFamide (Trica-SIFa; TYRKPPFNGSIFamide), an arginine-vasopressin-related peptide (Trica-AVP; CLITNCPRGamide) and an ITP-related peptide (Trica-ITP). No evidence was found for the presence of ‘A’ allatostatins (Y/FxFGLamides) or corazonin, either in T. molitor , or in the genome of T. castaneum .
Chihming Yin - One of the best experts on this subject based on the ideXlab platform.
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mutations in insulin signaling pathway alter juvenile hormone synthesis in drosophila melanogaster
General and Comparative Endocrinology, 2005Co-Authors: Chihming Yin, Marc TatarAbstract:Juvenile hormone (JH) is a key endocrine regulator of insect metamorphosis, reproduction, and aging. The synthesis of JH is regulated by neuropeptides and biogenic amines, but the molecular and cellular basis of this control remains largely unknown. Genetic analysis of JH synthesis in Drosophila melanogaster mutant for insulin signaling may provide new and powerful insights. Mutants of the insulin receptor (InR) are slow to develop, small, infertile, and long-lived. We previously reported that mutants of InR had reduced JH synthesis as young adults, and that normal longevity and vitellogenesis were restored by topical application of a JH analog [Science 292 (2001) 107]. Here, we describe the 10-day adult age course of JH synthesis from isolated corpus allatum (CA) of InR and of chico, the insulin receptor substrate homolog. JH synthesis increased in wildtype flies to a maximum of 30fmol/gland/h at day 10. In contrast, homozygous InR mutants produced no more than 3 fmol/gland/h JH within the first 5 days, and only 7 fmol/gland/h at day 10. InR mutation disproportionately reduced the synthesis of JH III-bisepoxide, the major JH subtype of the fly. Mutation of chico also reduces body size and extends longevity [Science 292 (2001) 104; Aging Cell 1 (2002a) 75]. Both homozygous and heterozygous chico genotypes reduced JH synthesis, but only to 47 and 67%, respectively, of wildtype and without influencing the ratio of JH subtypes. Because JH synthetic rate does not correlate with the size of CA, it is not likely that insulin signaling mediates JH by impeding endocrine tissue development. Alternatively, we find Allatotropin-positive axons to be abundant in the adult brain and in the corpora cardiaca-corpus allatum complex but these neurons are less immunoreactive in the InR mutant genotype, suggesting that insulin signaling may affect JH synthesis through control of JH regulatory neuropeptides.
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allatotropic activity in the brain of female phormia regina diptera calliphoridae
Journal of Insect Physiology, 2002Co-Authors: Rong Kou, Chihming Yin, G Oremus, J G StoffolanoAbstract:In Phormia regina, the rate of juvenile hormone (JH) synthesis rises rapidly after the ingestion of an adequate protein meal. In a previous publication we have localized the neurons containing Manduca sexta Allatotropin (Mas-AT)-like substances in the brain of P. regina and demonstrated the allatotropic effect of synthetic Mas-AT in sugar-fed flies in vitro. In this current study, we examined the possible role of the brain of P. regina after the fly received a protein meal. In vitro studies showed that the brain releases, at 8 h after a protein meal, a factor(s) with a strong allatotropic effect. This factor(s) stimulates the corpus allatum (CA) to produce 6.9 times more juvenile hormones (JHs) than the control CA. Time course studies showed that the release of this allatotropic factor(s) is temporally controlled. Only the brains collected from flies at 6 and 8 h after the onset of a liver meal release allatotropic factor(s). Injection of anti-Mas-AT antiserum partially suppressed the fly follicle development in vivo. Presence of anti-Mas-AT antiserum decreased the allatotropic effect of the brain released allatotropic factor(s) in vitro. In addition to a Mas-AT-like substance, it is possible that the brains of liver-fed P. regina females may synthesize other allatotropic factors that are chemically unrelated or partially related to Mas-AT, which cannot be recognized/neutralized by our anti-Mas-AT antiserum.
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immunolocalization and possible effect of a moth Allatotropin like substance in a fly phormia regina diptera calliphoridae
Journal of Insect Physiology, 2001Co-Authors: Rong Kou, J G Stoffolano, Zongshun Wang, Chihming YinAbstract:Abstract Insect Allatotropin upregulates the biosynthesis of juvenile hormones by the corpus allatum. We raised two rabbit antisera against the Allatotropin of Manduca sexta (Mas AT) using a synthetic, multiple-antigenic-peptide that contains a branching heptalysine core and eight Mas AT molecules. Both antisera recognized specifically the same neurons in the larval brain, frontal ganglion and terminal abdominal ganglion of M. sexta as previously reported by others. Immunoassay showed reactivity specific to the Mas AT. Very low or nearly no cross-reactivity was found for two Mas AT-like peptides, a myotropin from Locusta migratoria and a Mas AT-like peptide deduced from the DNA sequence of Aedes aegypti, respectively. Immunopositive neurons also were identified in adult Phormia regina, Dacus dorsalis, Oncopeltus fasciatus, and Mythimna loreyi, and in larval M. loreyi, Bombyx mori, and Andraca bipunctata. At 20 pmol per 25 μl incubation medium (i.e. 8×10−7 M), synthetic Mas AT significantly stimulated in vitro juvenile hormone biosynthesis by the corpus allatum of adult, sugar-fed females of P. regina to 2.64-fold that of controls. Thus, this study provides the first demonstration that at the higher end of the physiological concentration range, the Mas AT has allatotropic effect in vitro to CA of non-lepidopterans. However, in vivo functions of Mas AT and/or Mas AT-like peptide in P. regina remain to be defined.