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Liliane Schoofs - One of the best experts on this subject based on the ideXlab platform.
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a combined strategy of Neuropeptide prediction and tandem mass spectrometry identifies evolutionarily conserved ancient Neuropeptides in the sea anemone nematostella vectensis
PLOS ONE, 2019Co-Authors: Eisuke Hayakawa, Thomas W Holstein, Hiroshi Watanabe, Gerben Menschaert, Geert Baggerman, Liliane SchoofsAbstract:Neuropeptides are a class of bioactive peptides shown to be involved in various physiological processes, including metabolism, development, and reproduction. Although Neuropeptide candidates have been predicted from genomic and transcriptomic data, comprehensive characterization of Neuropeptide repertoires remains a challenge owing to their small size and variable sequences. De novo prediction of Neuropeptides from genome or transcriptome data is difficult and usually only efficient for those peptides that have identified orthologs in other animal species. Recent peptidomics technology has enabled systematic structural identification of Neuropeptides by using the combination of liquid chromatography and tandem mass spectrometry. However, reliable identification of naturally occurring peptides using a conventional tandem mass spectrometry approach, scanning spectra against a protein database, remains difficult because a large search space must be scanned due to the absence of a cleavage enzyme specification. We developed a pipeline consisting of in silico prediction of candidate Neuropeptides followed by peptide-spectrum matching. This approach enables highly sensitive and reliable Neuropeptide identification, as the search space for peptide-spectrum matching is highly reduced. Nematostella vectensis is a basal eumetazoan with one of the most ancient nervous systems. We scanned the Nematostella protein database for sequences displaying structural hallmarks typical of eumetazoan Neuropeptide precursors, including amino- and carboxyterminal motifs and associated modifications. Peptide-spectrum matching was performed against a dataset of peptides that are cleaved in silico from these putative peptide precursors. The dozens of newly identified Neuropeptides display structural similarities to bilaterian Neuropeptides including tachykinin, myoinhibitory peptide, and neuromedin-U/pyrokinin, suggesting these Neuropeptides occurred in the eumetazoan ancestor of all animal species.
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a combined strategy of Neuropeptide predictions and tandem mass spectrometry identifies evolutionarily conserved ancient Neuropeptides in the sea anemone nematostella vectensis
bioRxiv, 2019Co-Authors: Eisuke Hayakawa, Thomas W Holstein, Hiroshi Watanabe, Gerben Menschaert, Geert Baggerman, Liliane SchoofsAbstract:Abstract Neuropeptides are a class of bioactive peptides and are responsible for various physiological processes including metabolism, development and reproduction. Although accumulated genome and transcriptome data have reported a number of Neuropeptide candidates, it still remains difficult to obtain a comprehensive view of Neuropeptide repertoires due to their small and variable nature. Neuropeptide prediction tools usually work only for those peptides for which sequentially related homologs have previously been identified. Recent peptidomics technology has enabled systematic structural identification of Neuropeptides by using the combination of liquid chromatography and tandem mass spectrometry. However, obtaining reliable identifications of endogenous peptides is still difficult using a conventional tandem mass spectrometry-based peptide identification approach using protein database because a large search space has to be scanned due to the absence of a cleavage enzyme specification. We developed a pipeline consisting of the prediction of in silico cleaved endogenous Neuropeptides followed by peptide-spectrum matching enabling highly sensitive and reliable Neuropeptide identification. This approach effectively reduces the search space of peptide-spectrum matching, and thus increases search sensitivity. To identify Neuropeptides in Nematostella vectensis, a basal eumetazoan having one of the most primitive nervous systems, we scanned the Nematostella protein database for sequences displaying structural hallmarks of metazoan Neuropeptides, including C/N-terminal structures and modifications. Peptide-spectrum matching was performed against the in silico cleaved peptides and successfully identified dozens of Neuropeptides at high confidence. The identification of Nematostella Neuropeptides structurally related the tachykinin, GnRH/AKH, neuromedin-U/pyrokinin peptide families indicate that these peptides already originated in the eumetazoan ancestor of all animal species, most likely concomitantly with the development of a nervous system.
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A Caenorhabditis elegans Mass Spectrometric Resource for Neuropeptidomics
Journal of The American Society for Mass Spectrometry, 2018Co-Authors: Sven Van Bael, Liliane Schoofs, Kurt Boonen, Sven Zels, Isabel Beets, Liesbet TemmermanAbstract:Neuropeptides are important signaling molecules used by nervous systems to mediate and fine-tune neuronal communication. They can function as neurotransmitters or neuromodulators in neural circuits, or they can be released as neurohormones to target distant cells and tissues. Neuropeptides are typically cleaved from larger precursor proteins by the action of proteases and can be the subject of post-translational modifications. The short, mature Neuropeptide sequences often entail the only evolutionarily reasonably conserved regions in these precursor proteins. Therefore, it is particularly challenging to predict all putative bioactive peptides through in silico mining of Neuropeptide precursor sequences. Peptidomics is an approach that allows de novo characterization of peptides extracted from body fluids, cells, tissues, organs, or whole-body preparations. Mass spectrometry, often combined with on-line liquid chromatography, is a hallmark technique used in peptidomics research. Here, we used an acidified methanol extraction procedure and a quadrupole-Orbitrap LC-MS/MS pipeline to analyze the neuropeptidome of Caenorhabditis elegans . We identified an unprecedented number of 203 mature Neuropeptides from C. elegans whole-body extracts, including 35 peptides from known, hypothetical, as well as from completely novel Neuropeptide precursor proteins that have not been predicted in silico. This set of biochemically verified peptide sequences provides the most elaborate C. elegans reference neurpeptidome so far. To exploit this resource to the fullest, we make our in-house database of known and predicted Neuropeptides available to the community as a valuable resource. We are providing these collective data to help the community progress, amongst others, by supporting future differential and/or functional studies. Graphical Abstract ᅟ
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mass spectrometric evidence for Neuropeptide amidating enzymes in caenorhabditis elegans
Journal of Biological Chemistry, 2018Co-Authors: Sven Van Bael, Jan Watteyne, Wouter De Haes, Gerben Menschaert, Liliane Schoofs, Kurt Boonen, Niels Ringstad, Robert H Horvitz, Steven J Husson, Liesbet TemmermanAbstract:Neuropeptides constitute a vast and functionally diverse family of neurochemical signaling molecules and are widely involved in the regulation of various physiological processes. The nematode Caenorhabditis elegans is well-suited for the study of Neuropeptide biochemistry and function, as Neuropeptide biosynthesis enzymes are not essential for C. elegans viability. This permits the study of Neuropeptide biosynthesis in mutants lacking certain Neuropeptide-processing enzymes. Mass spectrometry has been used to study the effects of proprotein convertase and carboxypeptidase mutations on proteolytic processing of Neuropeptide precursors and on the peptidome in C. elegans. However, the enzymes required for the last step in the production of many bioactive peptides, the carboxyl-terminal amidation reaction, have not been characterized in this manner. Here, we describe three genes that encode homologs of Neuropeptide amidation enzymes in C. elegans and used tandem LC-MS to compare Neuropeptides in WT animals with those in newly generated mutants for these putative amidation enzymes. We report that mutants lacking both a functional peptidylglycine α-hydroxylating monooxygenase and a peptidylglycine α-amidating monooxygenase had a severely altered Neuropeptide profile and also a decreased number of offspring. Interestingly, single mutants of the amidation enzymes still expressed some fully processed amidated Neuropeptides, indicating the existence of a redundant amidation mechanism in C. elegans. All MS data are available via ProteomeXchange with the identifier PXD008942. In summary, the key steps in Neuropeptide processing in C. elegans seem to be executed by redundant enzymes, and loss of these enzymes severely affects brood size, supporting the need of amidated peptides for C. elegans reproduction.
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Peptidomics of Neuropeptidergic Tissues of the Tsetse Fly Glossina morsitans morsitans
Journal of The American Society for Mass Spectrometry, 2015Co-Authors: Jelle Caers, Liliane Schoofs, Kurt Boonen, Jan Abbeele, Liesbeth Rompay, Matthias B. HielAbstract:Neuropeptides and peptide hormones are essential signaling molecules that regulate nearly all physiological processes. The recent release of the tsetse fly genome allowed the construction of a detailed in silico Neuropeptide database (International Glossina Genome Consortium, Science 344 , 380–386 ( 2014 )), as well as an in-depth mass spectrometric analysis of the most important Neuropeptidergic tissues of this medically and economically important insect species. Mass spectrometric confirmation of predicted peptides is a vital step in the functional characterization of Neuropeptides, as in vivo peptides can be modified, cleaved, or even mispredicted. Using a nanoscale reversed phase liquid chromatography coupled to a Q Exactive Orbitrap mass spectrometer, we detected 51 putative bioactive Neuropeptides encoded by 19 precursors: adipokinetic hormone (AKH) I and II, allatostatin A and B, capability/pyrokinin (capa/PK), corazonin, calcitonin-like diuretic hormone (CT/DH), FMRFamide, hugin, leucokinin, myosuppressin, natalisin, Neuropeptide-like precursor (NPLP) 1, orcokinin, pigment dispersing factor (PDF), RYamide, SIFamide, short Neuropeptide F (sNPF) and tachykinin. In addition, propeptides, truncated and spacer peptides derived from seven additional precursors were found, and include the precursors of allatostatin C, crustacean cardioactive peptide, corticotropin releasing factor-like diuretic hormone (CRF/DH), ecdysis triggering hormone (ETH), ion transport peptide (ITP), Neuropeptide F, and proctolin, respectively. The majority of the identified Neuropeptides are present in the central nervous system, with only a limited number of peptides in the corpora cardiaca–corpora allata and midgut. Owing to the large number of identified peptides, this study can be used as a reference for comparative studies in other insects. Graphical Abstract ᅟ
Reinhard Predel - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Coverage of Insect Neuropeptides in Tissue Sections by an Optimized Mass-Spectrometry-Imaging Protocol
2019Co-Authors: Lapo Ragionieri, Sander Liessem, Susanne Neupert, Michael Becker, Sören-oliver Deininger, Reinhard PredelAbstract:Mass spectrometry imaging (MSI) of Neuropeptides has become a well-established method with the ability to combine spatially resolved information from immunohistochemistry with peptidomics information from mass spectrometric analysis. Several studies have conducted MSI of insect neural tissues; however, these studies did not detect Neuropeptide complements in manners comparable to those of conventional peptidomics. The aim of our study was to improve sample preparation so that MSI could provide comprehensive and reproducible neuropeptidomics information. Using the cockroach retrocerebral complex, the presented protocol produces enhanced coverage of Neuropeptides at 15 μm spatial resolution, which was confirmed by parallel analysis of tissue extracts using electrospray-ionization MS. Altogether, more than 100 peptide signals from 15 Neuropeptide-precursor genes could be traced with high spatial resolution. In addition, MSI spectra confirmed differential prohormone processing and distinct Neuropeptide-based compartmentalization of the retrocerebral complex. We believe that our workflow facilitates incorporation of MSI in neuroscience-related topics, including the study of complex Neuropeptide interactions within the CNS
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transcriptomic and neuropeptidomic analysis of the stick insect carausius morosus
Journal of Proteome Research, 2018Co-Authors: Sander Liessem, Lapo Ragionieri, Susanne Neupert, Ansgar Büschges, Reinhard PredelAbstract:One of the most thoroughly studied insect species, with respect to locomotion behavior, is the stick insect Carausius morosus. Although detailed information exists on premotor networks controlling walking, surprisingly little is known about Neuropeptides, which are certainly involved in motor activity generation and modulation. So far, only few Neuropeptides were identified from C. morosus or related stick insects. We performed a transcriptome analysis of the central nervous system to assemble and identify 65 Neuropeptide and protein hormone precursors of C. morosus, including five novel putative Neuropeptide precursors without clear homology to known Neuropeptide precursors of other insects (Carausius Neuropeptide-like precursor 1, HanSolin, PK-like1, PK-like2, RFLamide). Using Q Exactive Orbitrap and MALDI-TOF mass spectrometry, 277 peptides including 153 likely bioactive mature Neuropeptides were confirmed. Peptidomics yielded a complete coverage for many of the Neuropeptide propeptides and confirmed a...
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toward a single cell based analysis of Neuropeptide expression in periplaneta americana antennal lobe neurons
The Journal of Comparative Neurology, 2012Co-Authors: Susanne Neupert, Joachim Schachtner, Debora Fusca, Peter Kloppenburg, Reinhard PredelAbstract:A multitude of potential neurotransmitters and neuromodulators, including peptides, have been detected in the antennal lobe (AL), the first synaptic relay of the central olfactory pathway in the insect brain. However, the functional role of Neuropeptides in this system has yet to be revealed. An important prerequisite to understanding the role of Neuropeptides is to match the functionally different cell types in the AL with their peptide profiles by using electrophysiological recordings combined with immunocytochemical studies and/or single-cell mass spectrometry. The olfactory system of Periplaneta americana is particularly well suited to accomplish this goal because several physiologically distinct neuron types can be unequivocally identified. With the aim to analyze the Neuropeptide inventory of the P. americana AL, this study is an essential step in this direction. First, we systematically analyzed different parts of the AL by matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry to obtain the complete set of Neuropeptides present. Altogether, 56 ion signals could be assigned to products of 10 Neuropeptide genes (allatostatins A, B, C, SIFamide, allatotropin, FMRFamide-related peptides [myosuppressin, short Neuropeptides F, extended FMRFamides], crustacean cardioactive peptide, tachykinin-related peptides). In a second step, a combination of immunocytochemistry and mass spectrometric profiling of defined AL compartments was used to reveal the spatial distribution of Neuropeptide-containing cells. Finally, we demonstrated the feasibility of MALDI-TOF mass spectrometric profiling of single AL neurons, which is an important precondition for combining electrophysiology with peptide profiling at the single-cell level.
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The neuropeptidomics of Ixodes scapularis synganglion
Journal of proteomics, 2009Co-Authors: Susanne Neupert, Reinhard Predel, William K. Russell, David H. Russell, O. F. Strey, Pete D. Teel, Ronald J. NachmanAbstract:Ticks (Ixodoidea) likely transmit the greatest variety of human and animal pathogens of any arthropod vector. Despite their medical significance little data is available about the messenger molecules in the central nervous system that coordinate all physiological processes in these animals, including behaviour. In our study, we performed the first comprehensive neuropeptidomic analysis of a tick species by using MALDI-TOF mass spectrometry. Specifically we analyzed the Neuropeptides in the synganglion of Ixodes scapularis. The forthcoming sequence of the genome of this species will represent the first genomic analysis of a member of the large subphylum Chelicerata. For our approach we used information from predicted Neuropeptide precursor sequences found in EST databases [Christie, AE. Neuropeptide discovery in Ixodoidea: an in silico investigation using publicly accessible expressed sequence tags. Gen Comp Endocrinol 2008;157:174–185] as well as data obtained by complete de novo sequencing. The direct tissue profiling yielded 20 Neuropeptides from 12 Neuropeptide precursors. The sequences of these Neuropeptides are not as unique as predicted; a comparison with the peptidome of other invertebrates shows a close relationship with insect Neuropeptides. This work will provide a resource for studying tick neurobiology and will hopefully also help to identify novel targets for tick and tick-borne disease control.
Liesbet Temmerman - One of the best experts on this subject based on the ideXlab platform.
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RPamide Neuropeptides NLP-22 and NLP-2 act through GnRH-like receptors to promote sleep and wakefulness in C. elegans
Scientific reports, 2020Co-Authors: Petrus Van Der Auwera, Lotte Frooninckx, Kristen Buscemi, Ryan T. Vance, Jan Watteyne, Olivier Mirabeau, Liesbet Temmerman, Wouter De Haes, Luca Fancsalszky, Alexander GottschalkAbstract:Sleep and wakefulness are fundamental behavioral states of which the underlying molecular principles are becoming slowly elucidated. Transitions between these states require the coordination of multiple neurochemical and modulatory systems. In Caenorhabditis elegans sleep occurs during a larval transition stage called lethargus and is induced by somnogenic Neuropeptides. Here, we identify two opposing Neuropeptide/receptor signaling pathways: NLP-22 promotes behavioral quiescence, whereas NLP-2 promotes movement during lethargus, by signaling through gonadotropin-releasing hormone (GnRH) related receptors. Both NLP-2 and NLP-22 belong to the RPamide Neuropeptide family and share sequence similarities with Neuropeptides of the bilaterian GnRH, adipokinetic hormone (AKH) and corazonin family. RPamide Neuropeptides dose-dependently activate the GnRH/AKH-like receptors GNRR-3 and GNRR-6 in a cellular receptor activation assay. In addition, nlp-22-induced locomotion quiescence requires the receptor gnrr-6. By contrast, wakefulness induced by nlp-2 overexpression is diminished by deletion of either gnrr-3 or gnrr-6. nlp-2 is expressed in a pair of olfactory AWA neurons and cycles with larval periodicity, as reported for nlp-22, which is expressed in RIA. Our data suggest that the somnogenic NLP-22 Neuropeptide signals through GNRR-6, and that both GNRR-3 and GNRR-6 are required for the wake-promoting action of NLP-2 Neuropeptides.
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A Caenorhabditis elegans Mass Spectrometric Resource for Neuropeptidomics
Journal of The American Society for Mass Spectrometry, 2018Co-Authors: Sven Van Bael, Liliane Schoofs, Kurt Boonen, Sven Zels, Isabel Beets, Liesbet TemmermanAbstract:Neuropeptides are important signaling molecules used by nervous systems to mediate and fine-tune neuronal communication. They can function as neurotransmitters or neuromodulators in neural circuits, or they can be released as neurohormones to target distant cells and tissues. Neuropeptides are typically cleaved from larger precursor proteins by the action of proteases and can be the subject of post-translational modifications. The short, mature Neuropeptide sequences often entail the only evolutionarily reasonably conserved regions in these precursor proteins. Therefore, it is particularly challenging to predict all putative bioactive peptides through in silico mining of Neuropeptide precursor sequences. Peptidomics is an approach that allows de novo characterization of peptides extracted from body fluids, cells, tissues, organs, or whole-body preparations. Mass spectrometry, often combined with on-line liquid chromatography, is a hallmark technique used in peptidomics research. Here, we used an acidified methanol extraction procedure and a quadrupole-Orbitrap LC-MS/MS pipeline to analyze the neuropeptidome of Caenorhabditis elegans . We identified an unprecedented number of 203 mature Neuropeptides from C. elegans whole-body extracts, including 35 peptides from known, hypothetical, as well as from completely novel Neuropeptide precursor proteins that have not been predicted in silico. This set of biochemically verified peptide sequences provides the most elaborate C. elegans reference neurpeptidome so far. To exploit this resource to the fullest, we make our in-house database of known and predicted Neuropeptides available to the community as a valuable resource. We are providing these collective data to help the community progress, amongst others, by supporting future differential and/or functional studies. Graphical Abstract ᅟ
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mass spectrometric evidence for Neuropeptide amidating enzymes in caenorhabditis elegans
Journal of Biological Chemistry, 2018Co-Authors: Sven Van Bael, Jan Watteyne, Wouter De Haes, Gerben Menschaert, Liliane Schoofs, Kurt Boonen, Niels Ringstad, Robert H Horvitz, Steven J Husson, Liesbet TemmermanAbstract:Neuropeptides constitute a vast and functionally diverse family of neurochemical signaling molecules and are widely involved in the regulation of various physiological processes. The nematode Caenorhabditis elegans is well-suited for the study of Neuropeptide biochemistry and function, as Neuropeptide biosynthesis enzymes are not essential for C. elegans viability. This permits the study of Neuropeptide biosynthesis in mutants lacking certain Neuropeptide-processing enzymes. Mass spectrometry has been used to study the effects of proprotein convertase and carboxypeptidase mutations on proteolytic processing of Neuropeptide precursors and on the peptidome in C. elegans. However, the enzymes required for the last step in the production of many bioactive peptides, the carboxyl-terminal amidation reaction, have not been characterized in this manner. Here, we describe three genes that encode homologs of Neuropeptide amidation enzymes in C. elegans and used tandem LC-MS to compare Neuropeptides in WT animals with those in newly generated mutants for these putative amidation enzymes. We report that mutants lacking both a functional peptidylglycine α-hydroxylating monooxygenase and a peptidylglycine α-amidating monooxygenase had a severely altered Neuropeptide profile and also a decreased number of offspring. Interestingly, single mutants of the amidation enzymes still expressed some fully processed amidated Neuropeptides, indicating the existence of a redundant amidation mechanism in C. elegans. All MS data are available via ProteomeXchange with the identifier PXD008942. In summary, the key steps in Neuropeptide processing in C. elegans seem to be executed by redundant enzymes, and loss of these enzymes severely affects brood size, supporting the need of amidated peptides for C. elegans reproduction.
Susanne Neupert - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Coverage of Insect Neuropeptides in Tissue Sections by an Optimized Mass-Spectrometry-Imaging Protocol
2019Co-Authors: Lapo Ragionieri, Sander Liessem, Susanne Neupert, Michael Becker, Sören-oliver Deininger, Reinhard PredelAbstract:Mass spectrometry imaging (MSI) of Neuropeptides has become a well-established method with the ability to combine spatially resolved information from immunohistochemistry with peptidomics information from mass spectrometric analysis. Several studies have conducted MSI of insect neural tissues; however, these studies did not detect Neuropeptide complements in manners comparable to those of conventional peptidomics. The aim of our study was to improve sample preparation so that MSI could provide comprehensive and reproducible neuropeptidomics information. Using the cockroach retrocerebral complex, the presented protocol produces enhanced coverage of Neuropeptides at 15 μm spatial resolution, which was confirmed by parallel analysis of tissue extracts using electrospray-ionization MS. Altogether, more than 100 peptide signals from 15 Neuropeptide-precursor genes could be traced with high spatial resolution. In addition, MSI spectra confirmed differential prohormone processing and distinct Neuropeptide-based compartmentalization of the retrocerebral complex. We believe that our workflow facilitates incorporation of MSI in neuroscience-related topics, including the study of complex Neuropeptide interactions within the CNS
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transcriptomic and neuropeptidomic analysis of the stick insect carausius morosus
Journal of Proteome Research, 2018Co-Authors: Sander Liessem, Lapo Ragionieri, Susanne Neupert, Ansgar Büschges, Reinhard PredelAbstract:One of the most thoroughly studied insect species, with respect to locomotion behavior, is the stick insect Carausius morosus. Although detailed information exists on premotor networks controlling walking, surprisingly little is known about Neuropeptides, which are certainly involved in motor activity generation and modulation. So far, only few Neuropeptides were identified from C. morosus or related stick insects. We performed a transcriptome analysis of the central nervous system to assemble and identify 65 Neuropeptide and protein hormone precursors of C. morosus, including five novel putative Neuropeptide precursors without clear homology to known Neuropeptide precursors of other insects (Carausius Neuropeptide-like precursor 1, HanSolin, PK-like1, PK-like2, RFLamide). Using Q Exactive Orbitrap and MALDI-TOF mass spectrometry, 277 peptides including 153 likely bioactive mature Neuropeptides were confirmed. Peptidomics yielded a complete coverage for many of the Neuropeptide propeptides and confirmed a...
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toward a single cell based analysis of Neuropeptide expression in periplaneta americana antennal lobe neurons
The Journal of Comparative Neurology, 2012Co-Authors: Susanne Neupert, Joachim Schachtner, Debora Fusca, Peter Kloppenburg, Reinhard PredelAbstract:A multitude of potential neurotransmitters and neuromodulators, including peptides, have been detected in the antennal lobe (AL), the first synaptic relay of the central olfactory pathway in the insect brain. However, the functional role of Neuropeptides in this system has yet to be revealed. An important prerequisite to understanding the role of Neuropeptides is to match the functionally different cell types in the AL with their peptide profiles by using electrophysiological recordings combined with immunocytochemical studies and/or single-cell mass spectrometry. The olfactory system of Periplaneta americana is particularly well suited to accomplish this goal because several physiologically distinct neuron types can be unequivocally identified. With the aim to analyze the Neuropeptide inventory of the P. americana AL, this study is an essential step in this direction. First, we systematically analyzed different parts of the AL by matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry to obtain the complete set of Neuropeptides present. Altogether, 56 ion signals could be assigned to products of 10 Neuropeptide genes (allatostatins A, B, C, SIFamide, allatotropin, FMRFamide-related peptides [myosuppressin, short Neuropeptides F, extended FMRFamides], crustacean cardioactive peptide, tachykinin-related peptides). In a second step, a combination of immunocytochemistry and mass spectrometric profiling of defined AL compartments was used to reveal the spatial distribution of Neuropeptide-containing cells. Finally, we demonstrated the feasibility of MALDI-TOF mass spectrometric profiling of single AL neurons, which is an important precondition for combining electrophysiology with peptide profiling at the single-cell level.
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The neuropeptidomics of Ixodes scapularis synganglion
Journal of proteomics, 2009Co-Authors: Susanne Neupert, Reinhard Predel, William K. Russell, David H. Russell, O. F. Strey, Pete D. Teel, Ronald J. NachmanAbstract:Ticks (Ixodoidea) likely transmit the greatest variety of human and animal pathogens of any arthropod vector. Despite their medical significance little data is available about the messenger molecules in the central nervous system that coordinate all physiological processes in these animals, including behaviour. In our study, we performed the first comprehensive neuropeptidomic analysis of a tick species by using MALDI-TOF mass spectrometry. Specifically we analyzed the Neuropeptides in the synganglion of Ixodes scapularis. The forthcoming sequence of the genome of this species will represent the first genomic analysis of a member of the large subphylum Chelicerata. For our approach we used information from predicted Neuropeptide precursor sequences found in EST databases [Christie, AE. Neuropeptide discovery in Ixodoidea: an in silico investigation using publicly accessible expressed sequence tags. Gen Comp Endocrinol 2008;157:174–185] as well as data obtained by complete de novo sequencing. The direct tissue profiling yielded 20 Neuropeptides from 12 Neuropeptide precursors. The sequences of these Neuropeptides are not as unique as predicted; a comparison with the peptidome of other invertebrates shows a close relationship with insect Neuropeptides. This work will provide a resource for studying tick neurobiology and will hopefully also help to identify novel targets for tick and tick-borne disease control.
Maurice R Elphick - One of the best experts on this subject based on the ideXlab platform.
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Neuropeptide precursors and Neuropeptides in the sea cucumber Apostichopus japonicus: a genomic, transcriptomic and proteomic analysis
Scientific Reports, 2019Co-Authors: Muyan Chen, Alzbeta Talarovicova, Yingqiu Zheng, Kenneth B Storey, Maurice R ElphickAbstract:The sea cucumber Apostichopus japonicus is a foodstuff with very high economic value in China, Japan and other countries in south-east Asia. It is at the heart of a multibillion-dollar industry and to meet demand for this product, aquaculture methods and facilities have been established. However, there are challenges associated with optimization of reproduction, feeding and growth in non-natural environments. Therefore, we need to learn more about the biology of A . japonicus , including processes such as aestivation, evisceration, regeneration and albinism. One of the major classes of molecules that regulate physiology and behaviour in animals are Neuropeptides, and a few bioactive peptides have already been identified in A . japonicus . To facilitate more comprehensive investigations of Neuropeptide function in A . japonicus , here we have analysed genomic and transcriptomic sequence data and proteomic data to identify Neuropeptide precursors and Neuropeptides in this species. We identified 44 transcripts encoding Neuropeptide precursors or putative Neuropeptide precursors, and in some instances Neuropeptides derived from these precursors were confirmed by mass spectrometry. Furthermore, analysis of genomic sequence data enabled identification of the location of Neuropeptide precursor genes on genomic scaffolds and linkage groups (chromosomes) and determination of gene structure. Many of the precursors identified contain homologs of Neuropeptides that have been identified in other bilaterian animals. Precursors of Neuropeptides that have thus far only been identified in echinoderms were identified, including L- and F-type SALMFamides, AN peptides and others. Precursors of several peptides that act as modulators of neuromuscular activity in A . japonicus were also identified. The discovery of a large repertoire of Neuropeptide precursors and Neuropeptides provides a basis for experimental studies that investigate the physiological roles of Neuropeptide signaling systems in A . japonicus . Looking ahead, some of these Neuropeptides may have effects that could be harnessed to enable improvements in the aquaculture of this economically important species.
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Evolution of Neuropeptide signalling systems.
The Journal of experimental biology, 2018Co-Authors: Maurice R Elphick, Olivier Mirabeau, Dan LarhammarAbstract:Neuropeptides are a diverse class of neuronal signalling molecules that regulate physiological processes and behaviour in animals. However, determining the relationships and evolutionary origins of the heterogeneous assemblage of Neuropeptides identified in a range of phyla has presented a huge challenge for comparative physiologists. Here, we review revolutionary insights into the evolution of Neuropeptide signalling that have been obtained recently through comparative analysis of genome/transcriptome sequence data and by 'deorphanisation' of Neuropeptide receptors. The evolutionary origins of at least 30 Neuropeptide signalling systems have been traced to the common ancestor of protostomes and deuterostomes. Furthermore, two rounds of genome duplication gave rise to an expanded repertoire of Neuropeptide signalling systems in the vertebrate lineage, enabling neofunctionalisation and/or subfunctionalisation, but with lineage-specific gene loss and/or additional gene or genome duplications generating complex patterns in the phylogenetic distribution of paralogous Neuropeptide signalling systems. We are entering a new era in Neuropeptide research where it has become feasible to compare the physiological roles of orthologous and paralogous Neuropeptides in a wide range of phyla. Moreover, the ambitious mission to reconstruct the evolution of Neuropeptide function in the animal kingdom now represents a tangible challenge for the future.
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Discovery of novel representatives of bilaterian Neuropeptide families and reconstruction of Neuropeptide precursor evolution in ophiuroid echinoderms
2017Co-Authors: Meet Zandawala, Ismail Moghul, Luis Alfonso Yanez Guerra, Jérôme Delroisse, Nikara Abylkassimova, Andrew F. Hugall, Timothy D. O'hara, Maurice R ElphickAbstract:Neuropeptides are a diverse class of intercellular signaling molecules that mediate neuronal regulation of many physiological and behavioural processes. Recent advances in genome/transcriptome sequencing are enabling identification of Neuropeptide precursor proteins in species from a growing variety of animal taxa, providing new insights into the evolution of Neuropeptide signaling. Here detailed analysis of transcriptome sequence data from three brittle star species, Ophionotus victoriae, Amphiura filiformis and Ophiopsila aranea, has enabled the first comprehensive identification of Neuropeptide precursors in the class Ophiuroidea of the phylum Echinodermata. Representatives of over thirty bilaterian Neuropeptide precursor families were identified, some of which occur as paralogs. Furthermore, homologs of endothelin/CCHamide, eclosion hormone, Neuropeptide-F/Y and nucleobinin/nesfatin were discovered here in a deuterostome/echinoderm for the first time. The majority of ophiuroid Neuropeptide precursors contain a single copy of a Neuropeptide, but several precursors comprise multiple copies of identical or non-identical, but structurally-related, Neuropeptides. Here we performed an unprecedented investigation of the evolution of Neuropeptide copy-number over a period of ~270 million years by analysing sequence data from over fifty ophiuroid species, with reference to a robust phylogeny. Our analysis indicates that the composition of Neuropeptide cocktails is functionally important, but with plasticity over long evolutionary time scales.
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NG peptides: a novel family of neurophysin-associated Neuropeptides.
Gene, 2010Co-Authors: Maurice R ElphickAbstract:Neurophysins are prohormone-derived polypeptides that are required for biosynthesis of the neurohypophyseal hormones vasopressin and oxytocin. Accordingly, mutations in the neurophysin domain of the human vasopressin gene can cause diabetes insipidus. The association of neurophysins with vasopressin/oxytocin-type peptides dates back to the common ancestor of bilaterian animals and until recently it was thought to be unique. This textbook perspective on neurophysins changed with the discovery of a gene in the sea urchin Strongylocentrotus purpuratus (phylum Echinodermata) encoding a precursor protein comprising a neurophysin domain in association with NGFFFamide, a myoactive Neuropeptide that is structurally unrelated to vasopressin/oxytocin-type Neuropeptides (Elphick, M.R., Rowe, M.L., 2009. NGFFFamide and echinotocin: structurally unrelated myoactive Neuropeptides derived from neurophysin-containing precursors in sea urchins. J. Exp. Biol. 212, 1067-1077). What is not known, however, is when and how the association of neurophysin with NGFFFamide-like Neuropeptides originated. Here I report the discovery of genes encoding proteins comprising a neurophysin domain in association with putative NGFFFamide-like peptides in the hemichordate Saccoglossus kowalevskii (NGFWNamide and NGFYNamide) and in the cephalochordate Branchiostoma floridae (SFRNGVamide). Together with NGFFFamide, these peptides constitute a novel family of Neuropeptides in invertebrate deuterostomes that are derived from neurophysin-containing precursors and that have the sequence motif NG - "NG peptides". Genes encoding NG peptides in association with neurophysin were not found in protostomes, urochordates or vertebrates. Interestingly, however, SFRNGVamide is identical to the N-terminal region of Neuropeptide S, a peptide that modulates arousal and anxiety in mammals, whilst NGFFFamide shares sequence similarity with SIFamide (AYRKPPFNGSIFamide), a Neuropeptide that regulates sexual behaviour in Drosophila. Collectively, these data indicate that in an ancestor of extant deuterostomes a remarkable and unique event in the evolution of Neuropeptide signalling systems occurred when a neurophysin-encoding exon(s) derived from a vasopressin/oxytocin-type Neuropeptide gene became transcriptionally linked with another family of Neuropeptides - NG peptides.
