1
|
AI protein structure prediction-based modeling and mutagenesis of a protostome receptor and peptide ligands reveal key residues for their interaction. J Biol Chem 2022; 298:102440. [PMID: 36049520 PMCID: PMC9562341 DOI: 10.1016/j.jbc.2022.102440] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 11/24/2022] Open
Abstract
The protostome leucokinin (LK) signaling system, including LK peptides and their G protein-coupled receptors, has been characterized in several species. Despite progress in this area, molecular mechanisms governing LK peptide-receptor interactions remain to be elucidated. Previously, we identified a precursor protein for Aplysia leucokinin-like peptides (ALKs) that contains the greatest number of amidated peptides among LK precursors in all species identified so far. Here, we identified the first ALK receptor from Aplysia, ALKR. We used cell-based IP1 activation assays to demonstrate that the two ALK peptides with the most copies, ALK1 and ALK2, activated ALKR with high potencies. Other endogenous ALK-derived peptides bearing the FXXWX-amide motif also activated ALKR to various degrees. Our examination of cross-species activity of ALKs with the Anopheles LKR was consistent with a critical role for the FXXWX-amide motif in receptor activity. Furthermore, we showed, through alanine substitution of ALK1, the highly conserved phenylalanine (F), tryptophan (W), and C-terminal amidation were each essential for receptor activation. Finally, we used an AI-based protein structure prediction server (Robetta) and Autodock Vina to predict the ligand-bound conformation of ALKR. Our model predicted several interactions (i.e., hydrophobic interactions, hydrogen bonds, and amide-pi stacking) between ALK peptides and ALKR, and several of our substitution and mutagenesis experiments were consistent with the predicted model. In conclusion, our results provide important information defining the possible interactions between ALK peptides and their receptors. The workflow utilized here may be useful for studying other ligand-receptor interactions for a neuropeptide signaling system, particularly in protostomes.
Collapse
|
2
|
Nässel DR, Wu SF. Leucokinins: Multifunctional Neuropeptides and Hormones in Insects and Other Invertebrates. Int J Mol Sci 2021; 22:1531. [PMID: 33546414 PMCID: PMC7913504 DOI: 10.3390/ijms22041531] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 01/28/2021] [Accepted: 01/28/2021] [Indexed: 12/27/2022] Open
Abstract
Leucokinins (LKs) constitute a neuropeptide family first discovered in a cockroach and later identified in numerous insects and several other invertebrates. The LK receptors are only distantly related to other known receptors. Among insects, there are many examples of species where genes encoding LKs and their receptors are absent. Furthermore, genomics has revealed that LK signaling is lacking in several of the invertebrate phyla and in vertebrates. In insects, the number and complexity of LK-expressing neurons vary, from the simple pattern in the Drosophila larva where the entire CNS has 20 neurons of 3 main types, to cockroaches with about 250 neurons of many different types. Common to all studied insects is the presence or 1-3 pairs of LK-expressing neurosecretory cells in each abdominal neuromere of the ventral nerve cord, that, at least in some insects, regulate secretion in Malpighian tubules. This review summarizes the diverse functional roles of LK signaling in insects, as well as other arthropods and mollusks. These functions include regulation of ion and water homeostasis, feeding, sleep-metabolism interactions, state-dependent memory formation, as well as modulation of gustatory sensitivity and nociception. Other functions are implied by the neuronal distribution of LK, but remain to be investigated.
Collapse
Affiliation(s)
- Dick R. Nässel
- Department of Zoology, Stockholm University, S-10691 Stockholm, Sweden
| | - Shun-Fan Wu
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China;
| |
Collapse
|
3
|
Sangha V, Lange AB, Orchard I. Identification and cloning of the kinin receptor in the Chagas disease vector, Rhodnius prolixus. Gen Comp Endocrinol 2020; 289:113380. [PMID: 31891689 DOI: 10.1016/j.ygcen.2019.113380] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 12/23/2019] [Accepted: 12/27/2019] [Indexed: 11/24/2022]
Abstract
Within invertebrates, the kinin family of neuropeptides is responsible for the modulation of a host of physiological and behavioural processes. In Rhodnius prolixus, kinins are primarily responsible for eliciting myotropic effects on various feeding and diuresis-related tissues. Here, the R. prolixus kinin receptor (RhoprKR) has been identified, cloned and sequenced from the central nervous system (CNS) and hindgut of R. prolixus. Sequence analyses show high similarity and identity between RhoprKR and other cloned invertebrate kinin receptors. The expression profile of RhoprKR shows the RhoprKR transcript throughout the R. prolixus gut, with highest expression in the hindgut, suggesting a role of Rhopr-kinins in various aspects of feeding and digestion. RNA interference (RNAi)-mediated knockdown of the RhoprKR transcript resulted in a significant reduction of hindgut contractions in response to Rhopr-kinin 2 and an Aib-containing kinin analog. dsRhoprKR- injected insects also consumed a significantly larger meal, suggesting a role of Rhopr-kinins in satiety.
Collapse
Affiliation(s)
- Vishal Sangha
- Department of Biology University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON L5L 1C6, Canada.
| | - Angela B Lange
- Department of Biology University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON L5L 1C6, Canada.
| | - Ian Orchard
- Department of Biology University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON L5L 1C6, Canada.
| |
Collapse
|
4
|
Sangha V, Nachman RJ, Lange A, Orchard I. Physiological effects of biostable kinin and CAPA analogs in the Chagas disease vector, Rhodnius prolixus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 114:103223. [PMID: 31465823 DOI: 10.1016/j.ibmb.2019.103223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/06/2019] [Accepted: 08/21/2019] [Indexed: 06/10/2023]
Abstract
In the Chagas disease vector Rhodnius prolixus, the kinin and CAPA family of neuropeptides are implicated in feeding and diuresis-related behaviours, with Rhopr-kinins stimulating contractions of the midgut, salivary glands, and hindgut, and RhoprCAPA-2 functioning as an anti-diuretic hormone. The current study examined the effects of kinin and CAPA neuropeptides and their analogs on feeding and diuresis, and on hindgut contractions and MT fluid secretion in R. prolixus. The biostable Aib-containing kinin analog 2139[Φ1]wp-2 was found to have antifeedant effects, and to be more potent than Rhopr-kinin 2 in stimulating hindgut contractions. The CAPA analog 2129-SP3[Φ3]wp-2 induced the intake of a larger blood meal, and increased the rate of post-prandial rapid diuresis. RhoprCAPA-2, but not its analog, potentiated hindgut contractions induced by Rhopr-kinin 2. Potentiation was observed with the CAPA analog on 5-HT-stimulated increases in frequency of hindgut contractions, whereas RhoprCAPA-2 inhibited this 5-HT-mediated stimulation. The CAPA analog induced hindgut contractions and prevented the inhibition induced by RhoprCAPA-2 on 5-HT-stimulated MT secretion. These results demonstrate novel interactions between Rhopr-kinin and RhoprCAPA-2 on the hindgut, possibly influencing post-feeding excretion. The kinin analog is a potent agonist of the kinin receptor, and the CAPA analog an antagonist of the CAPA receptor. The use of neuropeptide mimetics is a promising approach to vector control as they can disrupt behaviours, and the effects of these neuropeptide analogs highlight their value as lead compounds, given their ability to interfere with epidemiologically-relevant behaviours.
Collapse
Affiliation(s)
- Vishal Sangha
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada.
| | - Ronald J Nachman
- Insect Control and Cotton Disease Research, Southern Plains Agricultural Research Centre, U.S Department of Agriculture, College Station, TX, 77845, USA
| | - Angela Lange
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Ian Orchard
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| |
Collapse
|
5
|
Komisarczuk AZ, Kongshaug H, Li M, Nilsen F. RNAi mediated myosuppressin deficiency affects muscle development and survival in the salmon louse (Lepeophtheirus salmonis). Sci Rep 2019; 9:6944. [PMID: 31061463 PMCID: PMC6502818 DOI: 10.1038/s41598-019-43515-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 04/23/2019] [Indexed: 12/05/2022] Open
Abstract
Muscle activity is regulated by stimulatory and inhibitory neuropeptides allowing for contraction and relaxation. In Arthropods, one of the important myoinhibitors is Myosuppressin, belonging to FMRFamide-like peptides, that was shown to have inhibitory effects on visceral muscle contraction and to regulate vital physiological processes including reproduction or feeding. We have identified myosuppressin in salmon louse Lepeophtheirus salmonis (LsalMS) and systematically characterised its function and complex abnormalities emerging after LsalMS knockdown by RNAi in all developmental stages in this species. Immunohistochemistry analysis localized the LsalMS mainly to the central nervous system, but also to the vital organs within the alimentary tract and the reproductive system. The most striking feature of LsalMS deficiency during lice development was severe reduction of the muscle content, with abnormalities detected in both the visceral and skeletal muscles. Moreover, down-regulation of LsalMS affects moulting, spermatophore deposition and feeding by affecting development of the intestinal wall and increasing its contraction frequency.
Collapse
Affiliation(s)
- Anna Z Komisarczuk
- Sea Lice Research Centre, Department of Biological Sciences, University of Bergen, Thormøhlensgate 53 A/B, 5008, Bergen, Norway.
| | - Heidi Kongshaug
- Sea Lice Research Centre, Department of Biological Sciences, University of Bergen, Thormøhlensgate 53 A/B, 5008, Bergen, Norway
| | - Ming Li
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, and State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Frank Nilsen
- Sea Lice Research Centre, Department of Biological Sciences, University of Bergen, Thormøhlensgate 53 A/B, 5008, Bergen, Norway
| |
Collapse
|
6
|
Zhang G, Vilim FS, Liu DD, Romanova EV, Yu K, Yuan WD, Xiao H, Hummon AB, Chen TT, Alexeeva V, Yin SY, Chen SA, Cropper EC, Sweedler JV, Weiss KR, Jing J. Discovery of leucokinin-like neuropeptides that modulate a specific parameter of feeding motor programs in the molluscan model, Aplysia. J Biol Chem 2017; 292:18775-18789. [PMID: 28924050 DOI: 10.1074/jbc.m117.795450] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/31/2017] [Indexed: 12/12/2022] Open
Abstract
A better understanding of neuromodulation in a behavioral system requires identification of active modulatory transmitters. Here, we used identifiable neurons in a neurobiological model system, the mollusc Aplysia, to study neuropeptides, a diverse class of neuromodulators. We took advantage of two types of feeding neurons, B48 and B1/B2, in the Aplysia buccal ganglion that might contain different neuropeptides. We performed a representational difference analysis (RDA) by subtraction of mRNAs in B48 versus mRNAs in B1/B2. The RDA identified an unusually long (2025 amino acids) peptide precursor encoding Aplysia leucokinin-like peptides (ALKs; e.g. ALK-1 and ALK-2). Northern blot analysis revealed that, compared with other ganglia (e.g. the pedal-pleural ganglion), ALK mRNA is predominantly present in the buccal ganglion, which controls feeding behavior. We then used in situ hybridization and immunohistochemistry to localize ALKs to specific neurons, including B48. MALDI-TOF MS on single buccal neurons revealed expression of 40 ALK precursor-derived peptides. Among these, ALK-1 and ALK-2 are active in the feeding network; they shortened the radula protraction phase of feeding motor programs triggered by a command-like neuron. We also found that this effect may be mediated by the ALK-stimulated enhancement of activity of an interneuron, which has previously been shown to terminate protraction. We conclude that our multipronged approach is effective for determining the structure and defining the diverse functions of leucokinin-like peptides. Notably, the ALK precursor is the first verified nonarthropod precursor for leucokinin-like peptides with a novel, marked modulatory effect on a specific parameter (protraction duration) of feeding motor programs.
Collapse
Affiliation(s)
- Guo Zhang
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Ferdinand S Vilim
- the Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | - Dan-Dan Liu
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Elena V Romanova
- the Beckman Institute for Advanced Science and Technology and Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - Ke Yu
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Wang-Ding Yuan
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Hui Xiao
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Amanda B Hummon
- the Beckman Institute for Advanced Science and Technology and Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - Ting-Ting Chen
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Vera Alexeeva
- the Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | - Si-Yuan Yin
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Song-An Chen
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Elizabeth C Cropper
- the Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | - Jonathan V Sweedler
- the Beckman Institute for Advanced Science and Technology and Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - Klaudiusz R Weiss
- the Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | - Jian Jing
- From the State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Advanced Institute for Life Sciences, School of Life Sciences, Nanjing University, Nanjing, Jiangsu 210023, China, .,the Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| |
Collapse
|
7
|
Yeoh JGC, Pandit AA, Zandawala M, Nässel DR, Davies SA, Dow JAT. DINeR: Database for Insect Neuropeptide Research. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 86:9-19. [PMID: 28502574 DOI: 10.1016/j.ibmb.2017.05.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 05/03/2017] [Accepted: 05/08/2017] [Indexed: 06/07/2023]
Abstract
Neuropeptides are responsible for regulating a variety of functions, including development, metabolism, water and ion homeostasis, and as neuromodulators in circuits of the central nervous system. Numerous neuropeptides have been identified and characterized. However, both discovery and functional characterization of neuropeptides across the massive Class Insecta has been sporadic. To leverage advances in post-genomic technologies for this rapidly growing field, insect neuroendocrinology requires a consolidated, comprehensive and standardised resource for managing neuropeptide information. The Database for Insect Neuropeptide Research (DINeR) is a web-based database-application used for search and retrieval of neuropeptide information of various insect species detailing their isoform sequences, physiological functionality and images of their receptor-binding sites, in an intuitive, accessible and user-friendly format. The curated data includes representatives of 50 well described neuropeptide families from over 400 different insect species. Approximately 4700 FASTA formatted, neuropeptide isoform amino acid sequences and over 200 records of physiological functionality have been recorded based on published literature. Also available are images of neuropeptide receptor locations. In addition, the data include comprehensive summaries for each neuropeptide family, including their function, location, known functionality, as well as cladograms, sequence alignments and logos covering most insect orders. Moreover, we have adopted a standardised nomenclature to address inconsistent classification of neuropeptides. As part of the H2020 nEUROSTRESSPEP project, the data will be actively maintained and curated, ensuring a comprehensive and standardised resource for the scientific community. DINeR is publicly available at the project website: http://www.neurostresspep.eu/diner/.
Collapse
Affiliation(s)
- Joseph G C Yeoh
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, UK
| | - Aniruddha A Pandit
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, UK
| | - Meet Zandawala
- Department of Zoology, Stockholm University, S-10691 Stockholm, Sweden
| | - Dick R Nässel
- Department of Zoology, Stockholm University, S-10691 Stockholm, Sweden
| | - Shireen-Anne Davies
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, UK
| | - Julian A T Dow
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, G12 8QQ Glasgow, Scotland, UK.
| |
Collapse
|
8
|
Lange AB, Nachman RJ, Kaczmarek K, Zabrocki J. Biostable insect kinin analogs reduce blood meal and disrupt ecdysis in the blood-gorging Chagas' disease vector, Rhodnius prolixus. Peptides 2016; 80:108-113. [PMID: 26807486 DOI: 10.1016/j.peptides.2016.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 01/13/2016] [Accepted: 01/14/2016] [Indexed: 11/18/2022]
Abstract
Rhodnius prolixus is a blood-gorging hemipteran that takes blood meals that are approximately 10 times its body weight. This blood meal is crucial for growth and development and is needed to ensure a successful molt into the next instar. Kinins are a multifunctional family of neuropeptides which have been shown to play a role in the control of feeding in a variety of insects. In this study, two biostable Aib-containing kinin analogs were tested to see if they interfere with blood-feeding and subsequent development into the next instar. One of the analogs, 1729 (Ac-R[Aib]FF[Aib]WGa), had no effect on the size of the blood meal or on the subsequent molting of the insect into the next instar. This analog also did not interfere with either short-term or long-term diuresis. The second analog, 1728 ([Aib]FF[Aib]WGa), appeared to be an antifeedant. Insects feeding on blood containing this analog (15μM) only consumed 60% of the blood meal taken by insects fed on blood without analog. Insects feeding on blood containing 1728 had a slower rate of rapid diuresis (diuresis in the first 3-5h after feeding) leading to less urine being excreted by 5days post feeding. The consequence of these effects was that insects fed on 1728 did not molt. This data indicates that the biostable Aib-containing analog 1728 disrupts normal growth and development in the blood-feeding insect, R. prolixus.
Collapse
Affiliation(s)
- Angela B Lange
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.
| | - Ronald J Nachman
- Insect Control and Cotton Disease Research, Southern Plains Agricultural Research Center, USDA, College Station, TX 77845, USA
| | - Krzysztof Kaczmarek
- Insect Control and Cotton Disease Research, Southern Plains Agricultural Research Center, USDA, College Station, TX 77845, USA; Institute of Organic Chemistry, Lodz University of Technology, 90-924 Lodz, Poland
| | - Janusz Zabrocki
- Insect Control and Cotton Disease Research, Southern Plains Agricultural Research Center, USDA, College Station, TX 77845, USA; Institute of Organic Chemistry, Lodz University of Technology, 90-924 Lodz, Poland
| |
Collapse
|
9
|
Bhatt G, da Silva R, Nachman RJ, Orchard I. The molecular characterization of the kinin transcript and the physiological effects of kinins in the blood-gorging insect, Rhodnius prolixus. Peptides 2014; 53:148-58. [PMID: 23624318 DOI: 10.1016/j.peptides.2013.04.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 04/16/2013] [Accepted: 04/17/2013] [Indexed: 11/24/2022]
Abstract
The dramatic feeding-related activities of the Chagas' disease vector, Rhodnius prolixus are under the neurohormonal regulation of serotonin and various neuropeptides. One such family of neuropeptides, the insect kinins, possess diuretic, digestive and myotropic activities in many insects. In this study, we have cloned and examined the spatial expression of the R. prolixus kinin (Rhopr-kinin) transcript. In addition, in situ hybridization has been used to map the distribution of neurons expressing the kinin transcript. Physiological bioassays demonstrate the myostimulatory effects of selected Rhopr-kinin peptides and also illustrate the augmented responses of hindgut contractions to co-application of Rhopr-kinin and a R. prolixus diuretic hormone. Two synthetic kinin analogs have also been examined on the hindgut. These reveal interesting properties including a relatively irreversible effect on hindgut contractions and activity at very low concentrations.
Collapse
Affiliation(s)
- Garima Bhatt
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.
| | - Rosa da Silva
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.
| | - Ronald J Nachman
- Areawide Pest Management Research, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX 77845, USA.
| | - Ian Orchard
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.
| |
Collapse
|
10
|
Coast GM, Schooley DA. Toward a consensus nomenclature for insect neuropeptides and peptide hormones. Peptides 2011; 32:620-31. [PMID: 21093513 DOI: 10.1016/j.peptides.2010.11.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 11/09/2010] [Accepted: 11/09/2010] [Indexed: 11/30/2022]
Abstract
The nomenclature currently in use for insect neuropeptide and peptide hormone families is reviewed and suggestions are made as to how it can be rationalized. Based upon this review, a number of conventions are advanced as a guide to a more rationale nomenclature. The scheme that is put forward builds upon the binomial nomenclature scheme proposed by Raina and Gäde in 1988, when just over 20 insect neuropeptides had been identified. Known neuropeptides and peptide hormones are assigned to 32 structurally distinct families, frequently with overlapping functions. The names given to these families are those that are currently in use, and describe a biological function, homology to known invertebrate/vertebrate peptides, or a conserved structural motif. Interspecific isoforms are identified using a five-letter code to indicate genus and species names, and intraspecific isoforms are identified by Roman or Arabic numerals, with the latter used to signify the order in which sequences are encoded on a prepropeptide. The proposed scheme is sufficiently flexible to allow the incorporation of novel peptides, and could be extended to other arthropods and non-arthropod invertebrates.
Collapse
Affiliation(s)
- Geoffrey M Coast
- School of Biological and Chemical Sciences, Birkbeck (University of London), Malet Street, London WC1E 7HX, UK.
| | | |
Collapse
|
11
|
Neupert S, Predel R, Russell WK, Davies R, Pietrantonio PV, Nachman RJ. Identification of tick periviscerokinin, the first neurohormone of Ixodidae: single cell analysis by means of MALDI-TOF/TOF mass spectrometry. Biochem Biophys Res Commun 2005; 338:1860-4. [PMID: 16289040 DOI: 10.1016/j.bbrc.2005.10.165] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Accepted: 10/24/2005] [Indexed: 12/01/2022]
Abstract
The first peptidergic neurohormone from the ticks Ixodes ricinus and Boophilus microplus has been identified by using a combination of immunocytochemistry and mass spectrometric analysis of single cells. The novel peptide (Ixori-PVK, PALIPFPRV-NH2) shows a high sequence homology with members of the insect periviscerokinin/CAP2b peptides that in insects are involved in the regulation of water balance. The function of this peptide in ticks is still unknown, but these pests consume large amounts of blood in a single blood meal which is a challenge for the regulation of diuretic processes. Thus, the novel peptide may be involved in one of the key physiological processes in ticks. High energy collision-induced dissociation was successfully used to distinguish between Leu/Ile ambiguities in single cell preparations. This is the first successful de novo sequencing of a peptide from single cell preparations of arthropods.
Collapse
Affiliation(s)
- Susanne Neupert
- Saxon Academy of Sciences, Research Group Jena, Erbertstrasse 1, 07743 Jena, Germany.
| | | | | | | | | | | |
Collapse
|
12
|
Radford JC, Davies SA, Dow JAT. Systematic G-protein-coupled receptor analysis in Drosophila melanogaster identifies a leucokinin receptor with novel roles. J Biol Chem 2002; 277:38810-7. [PMID: 12163486 DOI: 10.1074/jbc.m203694200] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Leucokinins are insect neuropeptides that stimulate hindgut motility and renal fluid secretion. Drosophila has a single leucokinin gene, pp, encoding the longest known leucokinin, Drosokinin. To identify its receptor, a genome-wide scan for G-protein-coupled receptors was performed in silico and candidate receptors identified by similarity to known tachykinin receptors. The deduced peptides were expressed, with a transgene for the calcium reporter aequorin, in S2 cells and only one gene (CG10626) encoded a protein that responded to Drosokinin. The properties of the heterologously expressed receptor (action through intracellular calcium with an EC(50) of 4 x 10(-11) m and a t(1/2) <1 s) match closely those reported for the action of Drosokinin on Malpighian (renal) tubules. Antibodies raised against the receptor identified known sites of leucokinin action: stellate cells of the Malpighian tubule, two triplets of cells in the pars intercerebralis of the adult central nervous system, and additional cells in larval central nervous system. Western blots and reverse transcription-PCR confirmed these locations, but also identified expression in male and female gonads. These tissues also displayed elevated calcium in response to Drosokinin, demonstrating novel roles for leucokinin. A functional genomic approach has thus yielded the first complete characterization of a leucokinin receptor in an insect.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Calcium/metabolism
- Drosophila Proteins/classification
- Drosophila Proteins/genetics
- Drosophila Proteins/metabolism
- Drosophila melanogaster/genetics
- Drosophila melanogaster/metabolism
- Embryo, Nonmammalian/anatomy & histology
- Embryo, Nonmammalian/physiology
- Female
- GTP-Binding Proteins/classification
- GTP-Binding Proteins/genetics
- GTP-Binding Proteins/metabolism
- Genes, Insect
- Genes, Reporter
- Humans
- Male
- Malpighian Tubules/cytology
- Malpighian Tubules/metabolism
- Molecular Sequence Data
- Nervous System/cytology
- Nervous System/metabolism
- Neuropeptides/metabolism
- Receptors, Cell Surface/classification
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Receptors, Neuropeptide/classification
- Receptors, Neuropeptide/genetics
- Receptors, Neuropeptide/metabolism
- Sequence Alignment
- Transgenes
Collapse
Affiliation(s)
- Jonathan C Radford
- Division of Molecular Genetics, Institute of Biomedical & Life Sciences, University of Glasgow, Glasgow G11 6NU, United Kingdom
| | | | | |
Collapse
|
13
|
Predel R, Nachman RJ, Gäde G. Myostimulatory neuropeptides in cockroaches: structures, distribution, pharmacological activities, and mimetic analogs. JOURNAL OF INSECT PHYSIOLOGY 2001; 47:311-324. [PMID: 11166295 DOI: 10.1016/s0022-1910(00)00129-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this brief overview we give the historical background on the discovery of myostimulatory neuropeptides in cockroaches. Related peptides were later found in other insect groups as well. We summarize the current knowledge on primary structures, localization, physiological and pharmacological effects of the different cockroach neuropeptides, including kinins, sulfakinins, pyrokinins, tachykinin-related peptides, periviscerokinins, corazonin, and proctolin. In addition, we briefly comment on the development of mimetic pseudopeptide analogs in the context of their possible use in insect pest management.
Collapse
Affiliation(s)
- R Predel
- Institut für Allgemeine Zoologie und Tierphysiologie, Friedrich-Schiller-Universität, Erbertstr. 1, 07743, Jena, Germany
| | | | | |
Collapse
|
14
|
Te Brugge VA, Nässel DR, Coast GM, Schooley DA, Orchard I. The distribution of a kinin-like peptide and its co-localization with a CRF-like peptide in the blood-feeding bug, Rhodnius prolixus. Peptides 2001; 22:161-73. [PMID: 11179809 DOI: 10.1016/s0196-9781(00)00373-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Rhodnius prolixus, a blood-feeding hemipteran insect, ingests large meals which are followed by rapid diuresis to eliminate excess water and salt. In Rhodnius, serotonin and an unidentified peptide(s) [33,34] have been shown to act as neurohormonal diuretic factors. In other insects, two families of diuretic peptides, the corticotropin releasing factor (CRF)-like, and kinin peptides [9], have been identified and sequenced. Recently, we demonstrated the presence of a CRF-like diuretic peptide in the CNS and digestive system of Rhodnius [47] using immunohistochemistry and bioassay. In this study, combining immunohistochemistry and radioimmunoassay (RIA) techniques, we show the presence of leucokinin-like peptide(s) in the CNS and digestive system of Rhodnius 5th instar. Additionally, double-label immunohistochemistry demonstrates that the leucokinin-like and CRF-like peptides are co-localized in the posterior lateral neurosecretory cells of the mesothoracic ganglionic mass (MTGM) and in neurohaemal areas on abdominal nerves one and two, suggesting the possibility of co-release of the peptides into the hemolymph.Partially purified extracts of the CNS and neurohaemal tissue were tested in vitro on Malpighian tubule secretion and cAMP assays. The factors eluting with increasing acetonitrile percentages from Sep-Pak cartridges were assayed in the presence or absence of ketanserin, a serotonin antagonist which blocks the effects of serotonin on Malpighian tubules. The results indicate activity of serotonin and a CRF-like diuretic peptide on Rhodnius Malpighian tubules, but fail to demonstrate activity of the leucokinin-like peptide(s). The rapid diuresis following feeding is a highly coordinated event, requiring the movement of water and salt across the epithelial cells of the crop into the hemolymph, and from the hemolymph across the cells of the Malpighian tubules. The urine then travels along the Malpighian tubules into the hindgut in order to be expelled. The presence of a leucokinin-like peptide(s) in the CNS and digestive system, which co-localizes with a CRF-like peptide(s), suggests that kinins may play a role in the rapid diuresis, although possibly not directly on the Malpighian tubules.
Collapse
Affiliation(s)
- V A Te Brugge
- Department of Zoology, University of Toronto, Toronto, Ontario M5S 3G5, Canada
| | | | | | | | | |
Collapse
|
15
|
Pietrantonio PV, Gibsona GE, Streya AA, Petzel D, Hayesa TK. Characterization of a leucokinin binding protein in Aedes aegypti (Diptera: Culicidae) Malpighian tubule. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2000; 30:1147-1159. [PMID: 11044661 DOI: 10.1016/s0965-1748(00)00091-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The insect myokinin (leucokinin-like) neuropeptide family includes peptides that have different physiological effects such as the induction of hindgut myotropic activity and stimulation of urine production. The C-terminal pentamer of myokinins Phe-X-(Ser/Pro/Ala)-Trp-Gly-amide [X=Phe, His, Asn, Ser or Tyr], had been previously determined as the minimum fragment able to elicit a functional response. The receptor(s) for these insect neuropeptides has not yet been identified. In order to characterize the Malpighian tubule leucokinin-like peptide receptor(s) from the yellow fever mosquito (Aedes aegypti), a leucokinin photoaffinity analogue (LPA) of sequence dAla-dTyr-Bpa-dLys-Phe-Phe-Ser-Trp-Gly-amide was designed based on structure/activity relationships for leucokinins. LPA caused depolarization of the transepithelial voltage (TEV) in female Malpighian tubule, confirming the activity of the peptide. The effective concentration to give half the maximum depolarization (EC(50)) was 17 nM. The (125)I-LPA was then used to characterize leucokinin binding proteins in female Malpighian tubule membranes. It specifically labeled and saturated a protein(s) of about 54 kDa as shown by SDS-PAGE/autoradiography and by competition experiments with excess unlabeled leucokinin analogues. (125)I-LPA bound to the 54 kDa protein(s) with a K(d) value of 13+/-3 nM in agreement with the EC(50) for the TEV bioassay. Altogether these data suggest that the 54 kDa protein is an Aedes-leucokinin receptor. This is the first characterization of an insect leucokinin receptor and reveals that LPA is a powerful tool to label insect myokinin receptors.
Collapse
Affiliation(s)
- P V Pietrantonio
- Department of Entomology, Texas A & M University, College Station, TX 77843-2475, USA.
| | | | | | | | | |
Collapse
|
16
|
Seinsche A, Dyker H, Lösel P, Backhaus D, Scherkenbeck J. Effect of helicokinins and ACE inhibitors on water balance and development of Heliothis virescens larvae. JOURNAL OF INSECT PHYSIOLOGY 2000; 46:1423-1431. [PMID: 10891570 DOI: 10.1016/s0022-1910(00)00065-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The diuretic activity of the helicokinins I (YFSPWG-amide), II (VRFSPWG-amide) and III (KVKFSAWG-amide) was tested on Heliothis virescens larvae. All three kinins increased fluid secretion in isolated Malpighian tubules in a dose-dependent manner. Injections into the haemolymph caused a significant reduction in weight gain after 24 h and, in the case of helicokinin I, led to an increased mortality of 43% within 6 days. When truncated analogues of helicokinin I were tested in vitro, only the pentapeptide (FSPWG-amide) stimulated fluid secretion. Tested in vivo the pentapeptide did not influence normal development of the larvae. An alanine scan of helicokinin I showed that the substitution of phenylalanine, tryptophan and glycine led to a massive decrease or even loss of diuretic activity. The substitution of the other amino acids had no effect in vitro. The ACE inhibitors captopril, enalapril-maleate and lisinopril were tested for their influence on the development of the larvae. In combination with one of the helicokinins the in vivo injection of the ACE inhibitors led to increased rates of mortality and/or reductions in pupal weight.
Collapse
Affiliation(s)
- A Seinsche
- Central Research, Bayer AG, LWZ Monheim, Geb. 6220, Alfred-Nobel-Strasse 50, 40789, Monheim, Germany
| | | | | | | | | |
Collapse
|
17
|
Torfs P, Nieto J, Veelaert D, Boon D, van de Water G, Waelkens E, Derua R, Calderón J, de Loof A, Schoofs L. The kinin peptide family in invertebrates. Ann N Y Acad Sci 2000; 897:361-73. [PMID: 10676463 DOI: 10.1111/j.1749-6632.1999.tb07906.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Kinins comprise a family of peptides that were first found in the central nervous system of insects and recently also in mollusks and crustaceans. After the isolation of the first members of the kinin family, the leukokinins from Leucophaea maderae, leukokinin-related peptides were found in the cricket Acheta domesticus and the locust Locusta migratoria, all through their ability to induce Leucophaea maderae hindgut contraction. Subsequently, kinins were found in the mosquitoes Culex salinarius and Aedes aegypti and in the earworm Helicoverpa zea. The first noninsect member of this family was isolated from a mollusk, the pond snail Lymnaea stagnalis. Most recently our group has isolated the first kinins from crustaceans. Six kinins were isolated from the white shrimp Penaeus vannamei. To date, 35 members of this family have been isolated. The first relatively small family of insect kinins has grown into an expanding and rather large family with members in insects, crustaceans, and mollusks. In this paper we discuss the kinin family in terms of method of isolation, structure, in vitro and in vivo activity, distribution, receptors, and signal transduction. We will compare the crustacean and insect members of the kinin family, using the data available on crustacea.
Collapse
Affiliation(s)
- P Torfs
- Zoological Institute, Katholieke Universiteit Leuven, Belgium.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Predel R, Kellner R, Rapus J, Penzlin H, Gáde G. Isolation and structural elucidation of eight kinins from the retrocerebral complex of the American cockroach, Periplaneta americana. REGULATORY PEPTIDES 1997; 71:199-205. [PMID: 9350979 DOI: 10.1016/s0167-0115(97)01029-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
By monitoring the contractile activity of the hindgut of the American cockroach in vitro eight myotropic neuropeptides were isolated from the retrocerebral complex of the American cockroach. Peptide sequence analysis and mass spectrometry yielded the following structures: Arg- Pro-Ser-Phe-Asn-Ser-Trp-Gly-NH2 (Pea-K-1), Asp-Ala-Ser-Phe-Ser-Ser-Trp-Gly-NH2 (Pea-K-2), Asp-Pro-Ser-Phe-Asn-Ser-Trp-Gly-NH2 (Pea-K-3), Gly-Ala-Gln-Phe-Ser-Ser-Trp-Gly-NH2 (Pea-K-4), Ser-Pro-Ala-Phe-Asn-Ser-Trp-Gly-NH2 (Pea-K-5), Asp-Pro-Ala-Phe-Ser-Ser-Trp-Gly-NH2 (Lem-K-7), Gly-Ala-Asp-Phe-Tyr-Ser-Trp-Gly-NH2 (Lem-K-8) and Ala-Phe-Ser-Ser-Trp-Gly-NH2 (Lom-K). The C-terminal sequence Phe-X-Ser-Trp-Gly-NH2 characterized the peptides as members of the insect kinin family. All structures were confirmed by comparison of retention times between synthetic and natural peptides. The threshold concentration for stimulatory effects of the synthetic peptides on the isolated hindgut was about 10(-9) M and there was no significant difference measured between the different kinin forms. These neuropeptides are the first members of the insect kinin-family isolated from the American cockroach. Their occurrence in the retrocerebral complex suggests a physiological role as neurohormone.
Collapse
Affiliation(s)
- R Predel
- Zoology Department, University of Cape Town, Rondebosch, South Africa.
| | | | | | | | | |
Collapse
|
19
|
Chung JS, Wheeler CH, Goldsworthy GJ, Coast GM. Properties of achetakinin binding sites on malpighian tubule membranes from the house cricket, Acheta domesticus. Peptides 1995; 16:375-82. [PMID: 7651887 DOI: 10.1016/0196-9781(94)00207-m] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A biologically active 125I-labeled analogue of AK-II (3'-hydroxyphenyl propionic-Gly-Gly-Gly-Phe-Ser-Pro-Trp-Gly-NH2) was used to investigate the properties of achetakinin binding sites on plasma membranes from Malpighian tubules of Acheta domesticus. With optimized conditions, binding was rapid, reversible, and specific, and saturation studies revealed a single class of binding sites with Kd 0.55 nM and Bmax 39.9 fmol/mg membrane protein. The affinities of achetakinins for binding sites on tubule membranes ranked AK-V > AK III > AK-II > AK-I > or = AK-IV, in general agreement with their potencies in functional assays. However, IC50 values were several orders of magnitude higher than corresponding values for EC50, which suggests a considerable receptor reserve.
Collapse
Affiliation(s)
- J S Chung
- Department of Biology, Birkbeck College, University of London, UK
| | | | | | | |
Collapse
|
20
|
Chen Y, Veenstra JA, Hagedorn H, Davis NT. Leucokinin and diuretic hormone immunoreactivity of neurons in the tobacco hornworm, Manduca sexta, and co-localization of this immunoreactivity in lateral neurosecretory cells of abdominal ganglia. Cell Tissue Res 1994; 278:493-507. [PMID: 7850860 DOI: 10.1007/bf00331367] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Because leucokinins stimulate diuresis in some insects, we wished to identify the neurosecretory cells in Manduca sexta that might be a source of leucokinin-like neurohormones. Immunostaining was done at various stages of development, using an antiserum to leucokinin IV. Bilateral pairs of neurosecretory cells in abdominal ganglia 3-7 of larvae and adults are immunoreactive; these cells project via the ipsilateral ventral nerves to the neurohemal transverse nerves. The immunoreactivity and size of these lateral cells greatly increases in the pharate adult, and this change appears to be related to a period of intensive diuresis occurring a few days before adult eclosion. Relationships of these neurons to cells that are immunoreactive to a M. sexta diuretic hormone were also investigated. Diuretic hormone and leucokinin immunoreactivity are co-localized in the lateral neurosecretory cells and their neurohemal projections. A median pair of leucokinin-immunoreactive, and a lateral pair of diuretic hormone-immunoreactive neurons in the larval terminal abdominal ganglion project to neurohemal release sites within the cryptonephridium. The immunoreactivity of these cells is lost as the cryptonephridium is eliminated during metamorphosis. This loss appears to be related to the change from the larval to adult pattern of diuresis.
Collapse
Affiliation(s)
- Y Chen
- Center for Insect Science, University of Arizona, Tucson 85721
| | | | | | | |
Collapse
|
21
|
Chen Y, Veenstra JA, Davis NT, Hagedorn HH. A comparative study of leucokinin-immunoreactive neurons in insects. Cell Tissue Res 1994; 276:69-83. [PMID: 7910521 DOI: 10.1007/bf00354786] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Antisera were raised against leucokinin IV, a member of the leucokinin peptide family. Immunohistochemical localization of leucokinin immunoreactivity in the brain of the cockroach Nauphoeta cinerea revealed neurosecretory cells in the pars intercerebralis and pars lateralis, several bilateral pairs of interneurons in the protocerebrum, and a group of interneurons in the optic lobe. Several immunoreactive interneurons were found in the thoracic ganglia, while the abdominal ganglia contained prominent immunoreactive neurosecretory cells, which projected to the lateral cardiac nerve. The presence of leucokinins in the abdominal nerve cord was confirmed by HPLC combined with ELISA. Leucokinin-immunoreactive neurosecretory cells were also found in the pars intercerebralis of the cricket Acheta domesticus and the mosquito Aedes aegypti, but not in the locust Schistocerca americana or the honey bee Apis mellifera. However, all these species have leucokinin-immunoreactive neurosecretory cells in the abdominal ganglia. The neurohemal organs innervated by abdominal leucokinin-immunoreactive cells were different in each species.
Collapse
Affiliation(s)
- Y Chen
- Center for Insect Science of the University of Arizona, Tucson 85721
| | | | | | | |
Collapse
|
22
|
Schoofs L, Holman GM, Hayes TK, Nachman RJ, De Loof A. Isolation, primary structure, and synthesis of locustapyrokinin: a myotropic peptide of Locusta migratoria. Gen Comp Endocrinol 1991; 81:97-104. [PMID: 2026322 DOI: 10.1016/0016-6480(91)90129-t] [Citation(s) in RCA: 95] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A neuropeptide which stimulates the motility of the cockroach hindgut has been isolated from an extract of 9000 brain-corpora cardiaca-corpora allata-subesophageal ganglion complexes of Locusta migratoria. Biological activity was monitored during HPLC purification by observing the myotropic effect of column fractions on the isolated hindgut of Leucophaea maderae. The primary structure of this myotropic peptide was established as a blocked 16-residue peptide: pGlu-Asp-Ser-Gly-Asp-Gly-Trp-Pro-Gln-Gln-Pro-Phe-Val-Pro-Arg-Leu-NH2. This novel locust peptide was designated as locustapyrokinin, or Lom-PK. Lom-PK was synthesized and shown to have chromatographic and biological properties identical to those of the native material. Lom-PK has a Phe-X-Pro-Arg-Leu-NH2 carboxy terminal in common with leucopyrokinin (or Lem-PK), a blocked myotropic neuropeptide isolated from the cockroach hindgut. The constituent amino acids of this C-terminal are important for biological activity on the Leucophaea hindgut. The primary structure of this novel insect peptide is, however, substantially different from Lem-PK at the amino-terminal sequence.
Collapse
Affiliation(s)
- L Schoofs
- Zoological Institute, Katholieke Universiteit Leuven, Belgium
| | | | | | | | | |
Collapse
|
23
|
Hayes TK, Pannabecker TL, Hinckley DJ, Holman GM, Nachman RJ, Petzel DH, Beyenbach KW. Leucokinins, a new family of ion transport stimulators and inhibitors in insect Malpighian tubules. Life Sci 1989; 44:1259-66. [PMID: 2716471 DOI: 10.1016/0024-3205(89)90362-7] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Leucokinins are octapeptides isolated from heads of the cockroach Leucophaea maderae. In the cockroach they increase motility of the isolated hindgut. Surprisingly, synthetic leucokinins have biological activity in a different insect and in a different tissue. In isolated Malpighian tubules of the yellow fever mosquito Aedes aegypti, leucokinins depolarize the transepithelial voltage. This effect on voltage is dependent on extracellular Cl. One leucokinin, LK-8, the effects of which were studied further in isolated Malpighian tubules, was found to inhibit transepithelial fluid secretion at low concentrations (10(-11) M threshold), and to stimulate fluid secretion at high concentrations (3.5 x 10(-9) M threshold). Together, the depolarizing effects on voltage and the stimulation of fluid secretion suggest that leucokinins increase the Cl permeability of the tubule wall thereby increasing the availability of Cl for secretion with Na, K and water. Structure-function comparisons of the seven leucokinins studied suggest that the active region of the octapeptide is segregated to the C-terminal pentapeptide. In view of the known effects of leucokinins on hindgut motility in the cockroach, our finding of effects in mosquito Malpighian tubules suggests that leucokinins may be widely distributed in insects where they may have diverse functions in a variety of organs.
Collapse
Affiliation(s)
- T K Hayes
- Department of Entomology, Texas A&M University, College Station 77840
| | | | | | | | | | | | | |
Collapse
|