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Sajadi F, Paluzzi JPV. Molecular characterization, localization, and physiological roles of ITP and ITP-L in the mosquito, Aedes aegypti. FRONTIERS IN INSECT SCIENCE 2024; 4:1374325. [PMID: 38654748 PMCID: PMC11035804 DOI: 10.3389/finsc.2024.1374325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 03/21/2024] [Indexed: 04/26/2024]
Abstract
The insect ion transport peptide (ITP) and its alternatively spliced variant, ITP-like peptide (ITP-L), belong to the crustacean hyperglycemic hormone family of peptides and are widely conserved among insect species. While limited, studies have characterized the ITP/ITP-L signaling system within insects, and putative functions including regulation of ion and fluid transport, ovarian maturation, and thirst/excretion have been proposed. Herein, we aimed to molecularly investigate Itp and Itp-l expression profiles in the mosquito, Aedes aegypti, examine peptide immunolocalization and distribution within the adult central nervous system, and elucidate physiological roles for these neuropeptides. Transcript expression profiles of both AedaeItp and AedaeItp-l revealed distinct enrichment patterns in adults, with AedaeItp expressed in the brain and AedaeItp-l expression predominantly within the abdominal ganglia. Immunohistochemical analysis within the central nervous system revealed expression of AedaeITP peptide in a number of cells in the brain and in the terminal ganglion. Comparatively, AedaeITP-L peptide was localized solely within the pre-terminal abdominal ganglia of the central nervous system. Interestingly, prolonged desiccation stress caused upregulation of AedaeItp and AedaeItp-l levels in adult mosquitoes, suggesting possible functional roles in water conservation and feeding-related activities. RNAi-mediated knockdown of AedaeItp caused an increase in urine excretion, while knockdown of both AedaeItp and AedaeItp-l reduced blood feeding and egg-laying in females as well as hindered egg viability, suggesting roles in reproductive physiology and behavior. Altogether, this study identifies AedaeITP and AedaeITP-L as key pleiotropic hormones, regulating various critical physiological processes in the disease vector, A. aegypti.
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Orchard I, Leyria J, Al-Dailami AN, Nachman RJ, Lange AB. Functional characterization of the kinin receptor in the Chagas disease vector Rhodnius prolixus; activity of native kinins and potent biostable Aib-containing insect kinin analogs. Peptides 2024; 172:171135. [PMID: 38103839 DOI: 10.1016/j.peptides.2023.171135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 12/19/2023]
Abstract
The causative agent for Chagas disease, Trypanosoma cruzi, is transmitted to a human host in the urine/feces of the kissing bug, Rhodnius prolixus, following blood feeding. Kinins are important chemical messengers in the overall control of blood feeding physiology in R. prolixus, including hindgut contractions and excretion. Thus, disruption in kinin signaling would have damaging consequences to the insect but also interfere with the transmission of Chagas Disease. Here, a heterologous functional receptor assay was used to confirm the validity of the previously cloned putative kinin G-protein-coupled receptor, RhoprKR, in Rhodnius prolixus. Three native R. prolixus kinins were chosen for analysis; two possessing the typical kinin WGamide C-terminal motif and one that possesses an atypical C-terminal WAamide. All three are potent (EC50 values in the nM range), with high efficacy, on CHO-K1-aeq cells expressing the RhoprKR, thereby confirming ligand binding. Members of three other R. prolixus peptide families, which are also myotropins (tachykinins, pyrokinins and sulfakinins) elicited little or no response. In addition, this heterologous receptor assay was used to test characteristics of kinin mimetics previously tested on tick and mosquito kinin receptors. Five α-aminoisobutyric acid (Aib) containing analogs were tested, and four found to have considerably higher potencies than the native kinins, with EC50 values in the pM range. Interestingly, adding Aib to the atypical WAamide kinin improves its EC50 value from 2 nM to 39 pM. Biostable kinin analogs may prove useful leads for novel pest control strategies. Since T. cruzi is transmitted to a human host in the urine/feces after blood feeding, disruption in kinin signaling would also interfere with the transmission of Chagas Disease.
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Affiliation(s)
- Ian Orchard
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada.
| | - Jimena Leyria
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Areej N Al-Dailami
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Ronald J Nachman
- Southern Plains Agricultural Research Center, USDA, College Station, TX, USA
| | - Angela B Lange
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
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Sajadi F, Vergara-Martínez MF, Paluzzi JPV. The V-type H +-ATPase is targeted in antidiuretic hormone control of the Malpighian "renal" tubules. Proc Natl Acad Sci U S A 2023; 120:e2308602120. [PMID: 38096413 PMCID: PMC10743368 DOI: 10.1073/pnas.2308602120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 11/01/2023] [Indexed: 12/18/2023] Open
Abstract
Like other insects, secretion by mosquito Malpighian tubules (MTs) is driven by the V-type H+-ATPase (VA) localized in the apical membrane of principal cells. In Aedes aegypti, the antidiuretic neurohormone CAPA inhibits secretion by MTs stimulated by select diuretic hormones; however, the cellular effectors of this inhibitory signaling cascade remain unclear. Herein, we demonstrate that the VA inhibitor bafilomycin selectively inhibits serotonin (5HT)- and calcitonin-related diuretic hormone (DH31)-stimulated secretion. VA activity increases in DH31-treated MTs, whereas CAPA abolishes this increase through a NOS/cGMP/PKG signaling pathway. A critical feature of VA activation involves the reversible association of the cytosolic (V1) and membrane (Vo) complexes. Indeed, higher V1 protein abundance was found in membrane fractions of DH31-treated MTs, whereas CAPA significantly decreased V1 abundance in membrane fractions while increasing it in cytosolic fractions. V1 immunolocalization was observed strictly in the apical membrane of DH31-treated MTs, whereas immunoreactivity was dispersed following CAPA treatment. VA complexes colocalized apically in female MTs shortly after a blood meal consistent with the peak and postpeak phases of diuresis. Comparatively, V1 immunoreactivity in MTs was more dispersed and did not colocalize with the Vo complex in the apical membrane at 3 h post blood meal, representing a time point after the late phase of diuresis has concluded. Therefore, CAPA inhibition of MTs involves reducing VA activity and promotes complex dissociation hindering secretion. Collectively, these findings reveal a key target in hormone-mediated inhibition of MTs countering diuresis that provides a deeper understanding of this critical physiological process necessary for hydromineral balance.
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Affiliation(s)
- Farwa Sajadi
- Department of Biology, York University, Toronto, ONM3J 1P3, Canada
| | - María Fernanda Vergara-Martínez
- Department of Biology, York University, Toronto, ONM3J 1P3, Canada
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México City, 04510, México
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Gong Q, Liu B, Yuan F, Tao R, Huang Y, Zeng X, Zhu X, Zhao Y, Zhang Y, Yang M, Wang J, Liu T, Zhang G. Controllably Self-Assembled Antibacterial Nanofibrils Based on Insect Cuticle Protein for Infectious Wound Healing. ACS NANO 2023; 17:23679-23691. [PMID: 37983051 DOI: 10.1021/acsnano.3c07131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2023]
Abstract
Developing self-assembled biomedical materials based on insect proteins is highly desirable due to their advantages of green, rich, and sustainable characters as well as excellent biocompatibility, which has been rarely explored. Herein, salt-induced controllable self-assembly, antibacterial performance, and infectious wound healing performance of an insect cuticle protein (OfCPH-2) originating from the Ostrinia furnacalis larva head capsule are investigated. Interestingly, the addition of salts could trigger the formation of beaded nanofibrils with uniform diameter, whose length highly depends on the salt concentration. Surprisingly, the OfCPH-2 nanofibrils not only could form functional films with broad-spectrum antibacterial abilities but also could promote infectious wound healing. More importantly, a possible wound healing mechanism was proposed, and it is the strong abilities of OfCPH-2 nanofibrils in promoting vascular formation and antibacterial activity that facilitate the process of infectious wound healing. Our exciting findings put forward instructive thoughts for developing innovative bioinspired materials based on insect proteins for wound healing and related biomedical fields.
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Affiliation(s)
- Qiuyu Gong
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science, Ministry of Education, Qingdao University of Science and Technology, Qingdao 266042, P. R. China
| | - Bohao Liu
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Fenghou Yuan
- School of Bioengineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Runyi Tao
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Yinjuan Huang
- State Key Laboratory for Mechanical Behavior of Materials, Shaanxi International Research Center for Soft Matter, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Xiaoyan Zeng
- Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Xingzhuo Zhu
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Yilong Zhao
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Yanpeng Zhang
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Mei Yang
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Jizhao Wang
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
| | - Tian Liu
- School of Bioengineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Guangjian Zhang
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
- Key Laboratory of Enhanced Recovery After Surgery of Integrated Chinese and Western Medicine, Administration of Traditional Chinese Medicine of Shaanxi Province, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P. R. China
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Yoon HJ, Price BE, Parks RK, Ahn SJ, Choi MY. Diuretic hormone 31 activates two G protein-coupled receptors with differential second messengers for diuresis in Drosophila suzukii. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 162:104025. [PMID: 37813200 DOI: 10.1016/j.ibmb.2023.104025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/06/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023]
Abstract
Diuretic hormones (DHs) bind to G protein-coupled receptors (GPCRs), regulating water and ion balance to maintain homeostasis in animals. Two distinct DHs are known in insects: calcitonin (CT)-like DH31 and corticotropin-releasing factor (CRF)-like DH44. In this study, we identified and characterized DH31 and two DH31 GPCR variants, DH31-Ra and DH31-Rb, from spotted-wing drosophila, Drosophila suzukii, a globally prevalent vinegar fly causing severe damage to small fruits. Both GPCRs are active, but DH31-Ra is the dominant receptor based on gene expression analyses and DH31 peptide binding affinities. A notable difference between the two variants lies in 1) the GPCR structures of their C-termini and 2) the utilization of second messengers, and the amino acid sequences of the two variants are identical. DH31-Ra contains 12 additional amino acids, providing different intracellular C-terminal configurations. DH31-Ra utilizes both cAMP and Ca2+ as second messengers, whereas DH31-Rb utilizes only cAMP; this is the first time reported for an insect CT-like DH31 peptide. DH31 stimulated fluid secretion in D. suzukii adults, and secretion increased in a dose-dependent manner. However, when the fly was injected with a mixture of DH31 and CAPA, an anti-diuretic hormone, fluid secretion was suppressed. Here, we discuss the structures of the DH31 receptors and the differential signaling pathways, including second messengers, involved in fly diuresis. These findings provide fundamental insights into the characterization of D. suzukii DH31 and DH31-Rs, and facilitate the identification of potential biological targets for D. suzukii management.
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Affiliation(s)
- Ho Jung Yoon
- USDA-ARS, Horticultural Crops Research Unit, 3420 NW Orchard Ave, Corvallis, OR, 97330, USA; Department of Horticulture, Oregon State University, 3420 NW Orchard Ave, Corvallis, OR, 97330, USA
| | - Briana E Price
- USDA-ARS, Horticultural Crops Research Unit, 3420 NW Orchard Ave, Corvallis, OR, 97330, USA
| | - Ryssa K Parks
- USDA-ARS, Horticultural Crops Research Unit, 3420 NW Orchard Ave, Corvallis, OR, 97330, USA; Department of Horticulture, Oregon State University, 3420 NW Orchard Ave, Corvallis, OR, 97330, USA
| | - Seung-Joon Ahn
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS, 39762, USA
| | - Man-Yeon Choi
- USDA-ARS, Horticultural Crops Research Unit, 3420 NW Orchard Ave, Corvallis, OR, 97330, USA.
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Waldman J, Klafke GM, Tirloni L, Logullo C, da Silva Vaz I. Putative target sites in synganglion for novel ixodid tick control strategies. Ticks Tick Borne Dis 2023; 14:102123. [PMID: 36716581 PMCID: PMC10033424 DOI: 10.1016/j.ttbdis.2023.102123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 12/23/2022] [Accepted: 01/07/2023] [Indexed: 01/21/2023]
Abstract
Acaricide resistance is a global problem that has impacts worldwide. Tick populations with broad resistance to all commercially available acaricides have been reported. Since resistance selection in ticks and their role in pathogen transmission to animals and humans result in important economic and public health burden, it is essential to develop new strategies for their control (i.e., novel chemical compounds, vaccines, biological control). The synganglion is the tick central nervous system and it is responsible for synthesizing and releasing signaling molecules with different physiological functions. Synganglion proteins are the targets of the majority of available acaricides. In this review we provide an overview of the mode-of-action and resistance mechanisms against neurotoxic acaricides in ticks, as well as putative target sites in synganglion, as a supporting tool to identify new target proteins and to develop new strategies for tick control.
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Affiliation(s)
- Jéssica Waldman
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Guilherme Marcondes Klafke
- Instituto de Pesquisas Veterinárias Desidério Finamor - Centro de Pesquisa em Saúde Animal, Secretaria da Agricultura, Pecuária e Desenvolvimento Rural, Eldorado do Sul, RS, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - Lucas Tirloni
- Laboratory of Bacteriology, Tick-Pathogen Transmission Unit, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA
| | - Carlos Logullo
- Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil; Laboratório de Bioquímica de Artrópodes Hematófagos, IBqM, Universidade Federal do Rio de Janeiro, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia - Entomologia Molecular, Rio de Janeiro, RJ, Brazil; Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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Pang X, Zhang J, Han Y, Zhang C, Sun L, Cao C. Functional characterization of a diuretic hormone receptor associated with desiccation, starvation and temperature tolerance in gypsy moth, Lymantria dispar. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 184:105079. [PMID: 35715033 DOI: 10.1016/j.pestbp.2022.105079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 02/27/2022] [Accepted: 03/09/2022] [Indexed: 06/15/2023]
Abstract
Variety of diuretic hormone neuropeptides is known to regulate water and ion balance in invertebrates. By activating their specific neuropeptide, diuretic hormone receptor (DHR) transmits extracellular signals into the cell, and then produces functional cell activity, which plays an important role in regulating physiology and behavior. However, little is known about the function of DHR gene in Lymantria dispar. DHR gene was firstly identified in L. dispar and its physiological functions were investigated using RNA interference (RNAi) technology. The results showed that except for the 6th instar larvae, the expression levels of DHR gene in the larval stages are higher than that in the egg, pupal and adult stages. The DHR gene is highly expressed in hindgut and midgut tissues. The L. dispar larvae significantly increased their water content and high temperature tolerance after the DHR was silenced, while decreasing excretion and feeding behavior. The physiological function of DHR is associated with desiccation, high temperature and starvation resistance. DHR could contribute to future development of novel insecticide to manage this global forest pest population.
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Affiliation(s)
- Xinru Pang
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, PR China
| | - Jingzhe Zhang
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, PR China
| | - Yang Han
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, PR China
| | - Chenshu Zhang
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, PR China
| | - Lili Sun
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, PR China
| | - Chuanwang Cao
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, PR China.
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Diesner M, Bläser M, Eckardt S, Iliffe TM, Boelen Theile E, Predel R. Expression pattern of CAPA/pyrokinin neuropeptide genes in Remipedia and silverfish: Rapid differentiation after gene duplication in early Hexapoda, followed by strong conservation of newly established features in insects. Peptides 2021; 144:170610. [PMID: 34242680 DOI: 10.1016/j.peptides.2021.170610] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/27/2021] [Accepted: 07/01/2021] [Indexed: 12/15/2022]
Abstract
Only few genes are known from insects that encode multiple neuropeptides, i.e., peptides that activate different receptors. Among those are the capa and pk genes, which differentiated within Hexapoda following gene duplication. In our study, we focus on the early stages of differentiation of these genes. Specifically: (1) What was the expression pattern of the ancestral capa/pk gene, i.e., prior to gene duplication? (2) What is the expression pattern of capa and pk in silverfish, whose ancestors diverged from Pterygota more than 400 mya? Our results suggest the location and projection of CAPA immunoreactive Va cells in abdominal ganglia (trunk ganglia in Remipedia) are a plesiomorphic trait that was already present in the ancestor of Remipedia and Hexapoda. General features of serial homology such as location of cells bodies, contralateral projection of primary neurites, and presumed peripheral peptide release from segmentally arranged neurohemal release sites could be observed in Remipedia and silverfish, but also in all Pterygota studied so far. Differences are mainly in the specific location of these peripheral release sites. This hypothetical basic pattern of capa/pk neurons underwent modifications in the anterior ganglia of the ventral nerve cord already in Remipedia. In silverfish, as in all Pterygota studied so far, pk expression in the CNS is apparently restricted to the gnathal ganglia, whereas capa expression is typical of abdominal Va cells. Thus, differentiation in the expression pattern of capa and pk genes occurred early in the evolution of Hexapoda; likely soon after the appearance of two separate genes.
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Affiliation(s)
- Max Diesner
- Department of Biology, Institute of Zoology, University of Cologne, D-50674, Cologne, Germany
| | - Marcel Bläser
- Department of Biology, Institute of Zoology, University of Cologne, D-50674, Cologne, Germany
| | - Sarah Eckardt
- Department of Biology, Institute of Zoology, University of Cologne, D-50674, Cologne, Germany
| | - Thomas M Iliffe
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, TX, 77554, USA
| | - Erik Boelen Theile
- Department of Biology, Institute of Zoology, University of Cologne, D-50674, Cologne, Germany
| | - Reinhard Predel
- Department of Biology, Institute of Zoology, University of Cologne, D-50674, Cologne, Germany.
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Sajadi F, Paluzzi JPV. Hormonal regulation and functional role of the "renal" tubules in the disease vector, Aedes aegypti. VITAMINS AND HORMONES 2021; 117:189-225. [PMID: 34420581 DOI: 10.1016/bs.vh.2021.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The Aedes aegypti mosquito is a vector responsible for transmitting various arboviruses including dengue and yellow fever. Their ability to regulate the ionic and water composition of their hemolymph is a major physiological phenomenon, allowing the mosquito to adapt to a range of ecological niches. Hematophagus insects, including the female A. aegypti, face the challenge of excess salt and water intake after a blood meal. Post-prandial diuresis is under rigorous control by neuroendocrine factors, acting on the Malpighian "renal" tubules (MTs), to regulate primary urine production. The MTs are made up of two cell types; mitochondria-rich principal cells, which facilitate active transport of Na+ and K+ cations across the membrane, and thin stellate cells, which allows for transepithelial Cl- secretion. The active driving force responsible for ion transport is the apical V-type H+ ATPase, which creates a proton gradient allowing for Na+ and/or K+ cation exchange through cation/H+ antiporters. Additionally, the basolaterally localized Na+-K+-2Cl- cotransporter (NKCC) is responsible for the transport of these ions from the hemolymph into the principal cells. Numerous studies have examined hormonal regulation of the mosquito MTs and identified several diuretics including serotonin (5HT), a calcitonin-related diuretic hormone 31 (DH31), a corticotropin-related factor like diuretic peptide (DH44), a kinin-related diuretic peptide, as well as anti-diuretic factors including CAPA peptides, all of which are known to regulate fluid and ion transport by the MTs. This review therefore focuses on the control of ionic homeostasis in A. aegypti mosquitoes, emphasizing the importance of the MTs, the channels and transporters involved in maintaining hydromineral balance, and the neuroendocrine regulation of both diuresis and anti-diuresis.
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Affiliation(s)
- Farwa Sajadi
- Department of Biology, York University, Toronto, ON, Canada
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10
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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.
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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;
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Xiong C, Kaczmarek K, Zabrocki J, Nachman RJ, Pietrantonio PV. Activity of native tick kinins and peptidomimetics on the cognate target G protein-coupled receptor from the cattle fever tick, Rhipicephalus microplus (Acari: Ixodidae). PEST MANAGEMENT SCIENCE 2020; 76:3423-3431. [PMID: 31794138 DOI: 10.1002/ps.5704] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/13/2019] [Accepted: 11/28/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Kinins are multifunctional neuropeptides that regulate key insect physiological processes such as diuresis, feeding, and ecdysis. However, the physiological roles of kinins in ticks are unclear. Furthermore, ticks have an expanded number of kinin paracopies in the kinin gene. Silencing the kinin receptor (KR) in females of Rhipicephalus microplus reduces reproductive fitness. Thus, it appears the kinin signaling system is important for tick physiology and its disruption may have potential for tick control. RESULTS We determined the activities of endogenous kinins on the KR, a G protein-coupled receptor, and identified potent peptidomimetics. Fourteen predicted R. microplus kinins (Rhimi-K), and 11 kinin analogs containing aminoisobutyric acid (Aib) were tested. The latter incorporated tick kinin sequences and/or were modified for enhanced resistance to arthropod peptidases. A high-throughput screen using a calcium fluorescence assay in 384-well plates was performed. All tested kinins and Aib analogs were full agonists. The most potent kinin and two kinin analogs were equipotent. Analogs 2414 ([Aib]FS[Aib]WGa) and 2412 ([Aib]FG[Aib]WGa) were the most active with EC50 values of 0.9 and 1.1 nM, respectively, matching the EC50 of the most potent tick kinin, Rhimi-K-14 (QDSFNPWGa) (EC50 = 1 nM). The potent analog 2415 ([Aib]FR[Aib]WGa, EC50 = 6.8 nM) includes both Aib molecules for resistance to peptidases and a positively charged residue, R, for enhanced water solubility and amphiphilic character. CONCLUSION These tick kinins and pseudopeptides expand the repertoire of reagents for tick physiology and toxicology towards finding novel targets for tick management. © 2019 Society of Chemical Industry.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX, USA
| | - Krzysztof Kaczmarek
- Institute of Organic Chemistry, Lodz University of Technology, Lodz, Poland
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX, USA
| | - Janusz Zabrocki
- Institute of Organic Chemistry, Lodz University of Technology, Lodz, Poland
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX, USA
| | - Ronald J Nachman
- Insect Neuropeptide Lab, Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, College Station, TX, USA
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12
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Sajadi F, Uyuklu A, Paputsis C, Lajevardi A, Wahedi A, Ber LT, Matei A, Paluzzi JPV. CAPA neuropeptides and their receptor form an anti-diuretic hormone signaling system in the human disease vector, Aedes aegypti. Sci Rep 2020; 10:1755. [PMID: 32020001 PMCID: PMC7000730 DOI: 10.1038/s41598-020-58731-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 01/20/2020] [Indexed: 01/07/2023] Open
Abstract
Insect CAPA neuropeptides are homologs of mammalian neuromedin U and are known to influence ion and water balance by regulating the activity of the Malpighian 'renal' tubules (MTs). Several diuretic hormones are known to increase primary fluid and ion secretion by insect MTs and, in adult female mosquitoes, a calcitonin-related peptide (DH31) called mosquito natriuretic peptide, increases sodium secretion to compensate for the excess salt load acquired during blood-feeding. An endogenous mosquito anti-diuretic hormone was recently described, having potent inhibitory activity against select diuretic hormones, including DH31. Herein, we functionally deorphanized, both in vitro and in vivo, a mosquito anti-diuretic hormone receptor (AedaeADHr) with expression analysis indicating highest enrichment in the MTs where it is localized within principal cells. Characterization using a heterologous in vitro system demonstrated the receptor was highly sensitive to mosquito CAPA neuropeptides while in vivo, AedaeADHr knockdown abolished CAPA-induced anti-diuretic control of DH31-stimulated MTs. CAPA neuropeptides are produced within a pair of neurosecretory cells in each of the abdominal ganglia, whose axonal projections innervate the abdominal neurohaemal organs, where these neurohormones are released into circulation. Lastly, pharmacological inhibition of nitric oxide synthase (NOS) and protein kinase G (PKG) signaling eliminated anti-diuretic activity of CAPA, highlighting the role of the second messenger cGMP and NOS/PKG in this anti-diuretic signaling pathway.
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Affiliation(s)
- Farwa Sajadi
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Ali Uyuklu
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Christine Paputsis
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Aryan Lajevardi
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Azizia Wahedi
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Lindsay Taylor Ber
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Andreea Matei
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada
| | - Jean-Paul V Paluzzi
- Department of Biology, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada.
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13
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Grandchamp A, Tahir S, Monget P. Natriuretic peptides appeared after their receptors in vertebrates. BMC Evol Biol 2019; 19:215. [PMID: 31771521 PMCID: PMC6878697 DOI: 10.1186/s12862-019-1517-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 09/20/2019] [Indexed: 01/05/2023] Open
Abstract
Background In mammals, the natriuretic system contains three natriuretic peptides, NPPA, NPPB and NPPC, that bind to three transmembrane receptors, NPR1, NPR2 and NPR3. The natriuretic peptides are known only in vertebrates. In contrast, the receptors have orthologs in all the animal taxa and in plants. However, in non-vertebrates, these receptors do not have natriuretic properties, and most of their ligands are unknown. How was the interaction of the NP receptors and the NP established in vertebrates? Do natriuretic peptides have orthologs in non-vertebrates? If so, what was the function of the interaction? How did that function change? If not, are the NP homologous to ancestral NPR ligands? Or did the receptor’s binding pocket completely change during evolution? Methods In the present study, we tried to determine if the pairs of natriuretic receptors and their ligands come from an ancestral pair, or if the interaction only appeared in vertebrates. Alignments, modeling, docking, research of positive selection, and motif research were performed in order to answer this question. Results We discovered that the binding pocket of the natriuretic peptide receptors was completely remodeled in mammals. We found several peptides in non vertebrates that could be related to human natriuretic peptides, but a set of clues, as well as modeling and docking analysis, suggest that the natriuretic peptides undoubtedly appeared later than their receptors during animal evolution. We suggest here that natriuretic peptide receptors in non vertebrates bind to other ligands. Conclusions The present study further support that vertebrate natriuretic peptides appeared after their receptors in the tree of life. We suggest the existence of peptides that resemble natriuretic peptides in non-vertebrate species, that might be the result of convergent evolution.
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Affiliation(s)
- Anna Grandchamp
- PRC, UMR85, INRA, CNRS, IFCE, Université de Tours, F-37380, Nouzilly, France
| | - Shifa Tahir
- PRC, UMR85, INRA, CNRS, IFCE, Université de Tours, F-37380, Nouzilly, France
| | - Philippe Monget
- PRC, UMR85, INRA, CNRS, IFCE, Université de Tours, F-37380, Nouzilly, France.
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14
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Xiong C, Kaczmarek K, Zabrocki J, Pietrantonio PV, Nachman RJ. Evaluation of Aib and PEG-polymer insect kinin analogs on mosquito and tick GPCRs identifies potent new pest management tools with potentially enhanced biostability and bioavailability. Gen Comp Endocrinol 2019; 278:58-67. [PMID: 30107140 DOI: 10.1016/j.ygcen.2018.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 07/02/2018] [Accepted: 08/01/2018] [Indexed: 11/22/2022]
Abstract
Insect kinins modulate aspects of diuresis, digestion, development, and sugar taste perception in tarsi and labellar sensilla in mosquitoes. They are, however, subject to rapid biological degradation by endogenous invertebrate peptidases. A series of α-aminoisobutyric (Aib) acid-containing insect kinin analogs incorporating sequences native to the Aedes aegypti mosquito aedeskinins were evaluated on two recombinant kinin invertebrate receptors stably expressed in cell lines, discovering a number of highly potent and biostable insect kinin mimics. On the Ae. aegypti mosquito kinin receptor, three highly potent, biostable Aib analogs matched the activity of the Aib-containing biostable insect kinin analog 1728, which previously showed disruptive and/or aversive activity in aphid, mosquito and kissing bug. These three analogs are IK-Aib-19 ([Aib]FY[Aib]WGa, EC50 = 18 nM), IK-Aib-12 (pQKFY[Aib]WGa, EC50 = 23 nM) and IK-Aib-20 ([Aib]FH[Aib]WGa, EC50 = 28 nM). On the Rhipicephalus (Boophilus) microplus tick receptor, IK-Aib-20 ([Aib]FH[Aib]WGa, EC50 = 2 nM) is more potent than 1728 by a factor of 3. Seven other potentially biostable analogs exhibited an EC50 range of 5-10 nM, all of which match the potency of 1728. Among the multi-Aib hexapeptide kinin analogs tested the tick receptor has a preference for the positively-charged, aromatic H over the aromatic residues Y and F in the X1 variable position ([Aib]FX1[Aib]WGa), whereas the mosquito receptor does not distinguish between them. In contrast, in a mono-Aib pentapeptide analog framework (FX1[Aib]WGa), both receptors exhibit a preference for Y over H in the variable position. Among analogs incorporating polyethylene glycol (PEG) polymer attachments at the N-terminus that can confer enhanced bioavailability and biostability, three matched or surpassed the potency of a positive control peptide. On the tick receptor IK-PEG-9 (P8-R[Aib]FF[Aib]WGa) was the most potent. Two others, IK-PEG-8 (P8-RFFPWGa) and IK-PEG-6 (P4-RFFPWGa), were most potent on the mosquito receptor, with the first surpassing the activity of the positive control peptide. These analogs and others in the IK-Aib series expand the toolbox of potent analogs accessible to invertebrate endocrinologists studying the structural requirements for bioactivity and the as yet unknown role of the insect kinins in ticks. They may contribute to the development of selective, environmentally friendly pest arthropod control agents.
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Affiliation(s)
- Caixing Xiong
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA
| | - Krzysztof Kaczmarek
- Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, 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 Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, College Station, TX 77845, USA; Institute of Organic Chemistry, Lodz University of Technology, 90-924 Lodz, Poland
| | | | - Ronald J Nachman
- Insect Control and Cotton Disease Research Unit, Southern Plains Agricultural Research Center, U.S. Department of Agriculture, 2881 F/B Road, College Station, TX 77845, USA.
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15
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Nässel DR, Zandawala M. Recent advances in neuropeptide signaling in Drosophila, from genes to physiology and behavior. Prog Neurobiol 2019; 179:101607. [PMID: 30905728 DOI: 10.1016/j.pneurobio.2019.02.003] [Citation(s) in RCA: 171] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/18/2019] [Accepted: 02/28/2019] [Indexed: 12/11/2022]
Abstract
This review focuses on neuropeptides and peptide hormones, the largest and most diverse class of neuroactive substances, known in Drosophila and other animals to play roles in almost all aspects of daily life, as w;1;ell as in developmental processes. We provide an update on novel neuropeptides and receptors identified in the last decade, and highlight progress in analysis of neuropeptide signaling in Drosophila. Especially exciting is the huge amount of work published on novel functions of neuropeptides and peptide hormones in Drosophila, largely due to the rapid developments of powerful genetic methods, imaging techniques and innovative assays. We critically discuss the roles of peptides in olfaction, taste, foraging, feeding, clock function/sleep, aggression, mating/reproduction, learning and other behaviors, as well as in regulation of development, growth, metabolic and water homeostasis, stress responses, fecundity, and lifespan. We furthermore provide novel information on neuropeptide distribution and organization of peptidergic systems, as well as the phylogenetic relations between Drosophila neuropeptides and those of other phyla, including mammals. As will be shown, neuropeptide signaling is phylogenetically ancient, and not only are the structures of the peptides, precursors and receptors conserved over evolution, but also many functions of neuropeptide signaling in physiology and behavior.
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Affiliation(s)
- Dick R Nässel
- Department of Zoology, Stockholm University, Stockholm, Sweden.
| | - Meet Zandawala
- Department of Zoology, Stockholm University, Stockholm, Sweden; Department of Neuroscience, Brown University, Providence, RI, USA.
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16
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Davies SA, Cabrero P, Marley R, Corrales GM, Ghimire S, Dornan AJ, Dow JAT. Epithelial Function in the Drosophila Malpighian Tubule: An In Vivo Renal Model. Methods Mol Biol 2019; 1926:203-221. [PMID: 30742274 DOI: 10.1007/978-1-4939-9021-4_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The insect renal (Malpighian) tubule has long been a model system for the study of fluid secretion and its neurohormonal control, as well as studies on ion transport mechanisms. To extend these studies beyond the boundaries of classical physiology, a molecular genetic approach together with the 'omics technologies is required. To achieve this in any vertebrate transporting epithelium remains a daunting task, as the genetic tools available are still relatively unsophisticated. Drosophila melanogaster, however, is an outstanding model organism for molecular genetics. Here we describe a technique for fluid secretion assays in the D. melanogaster equivalent of the kidney nephron. The development of this first physiological assay for a Drosophila epithelium, allowing combined approaches of integrative physiology and functional genomics, has now provided biologists with an entirely new model system, the Drosophila Malpighian tubule, which is utilized in multiple fields as diverse as kidney disease research and development of new modes of pest insect control.
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Affiliation(s)
- Shireen-A Davies
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK.
| | - Pablo Cabrero
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Richard Marley
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Guillermo Martinez Corrales
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Saurav Ghimire
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Anthony J Dornan
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Julian A T Dow
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK.
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17
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Yuan YY, Li M, Fan F, Qiu XH. Comparative transcriptomic analysis of larval and adult Malpighian tubules from the cotton bollworm Helicoverpa armigera. INSECT SCIENCE 2018; 25:991-1005. [PMID: 29178196 DOI: 10.1111/1744-7917.12561] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/28/2017] [Accepted: 10/31/2017] [Indexed: 06/07/2023]
Abstract
Malpighian tubules (MTs) are usually considered the key excretory and osmoregulatory organs of insects. However, increasing evidence has suggested that MTs perform many more functions than just osmoregulation. Until now, the molecular and physiological functions of MTs in the cotton bollworm (Helicoverpa armigera), a very important agricultural pest, are largely unknown. In this study, the transcriptomes of H. armigera MTs from larvae, male adults and female adults were sequenced using RNA-Seq technology, and comparative analyses of transcriptomes between two life stages (larval and adult) and between adult sexes were conducted. We generated a total of 84 643 high-quality unigenes, and identified a large number of abundant transcripts putatively encoding proteins involved in diuresis, detoxification, immunity, carbohydrate transport and metabolism, development and reproduction. We found that the expression pattern of unigenes was relatively similar between female and male adult MTs, but different between larval and adult MTs. Our data suggest that insect MTs may take multiple physiological functions as versatile organs. The extensive alterations in gene expression in MTs occurred from larvae to adults reflect an ecological adaptation to different feeding habits. Sexual dimorphism in the cotton bollworm is somewhat indicated by the transcriptional difference of genes related to carbohydrate metabolism, detoxification, immunity and reproduction in the MTs of male and female adults.
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Affiliation(s)
- Yi-Yang Yuan
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Mei Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Fan Fan
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- College of Plant Protection, Hebei Agricultural University, Baoding, Hebei Province, China
| | - Xing-Hui Qiu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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18
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MacMillan HA, Nazal B, Wali S, Yerushalmi GY, Misyura L, Donini A, Paluzzi JP. Anti-diuretic activity of a CAPA neuropeptide can compromise Drosophila chill tolerance. ACTA ACUST UNITED AC 2018; 221:jeb.185884. [PMID: 30104306 DOI: 10.1242/jeb.185884] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/03/2018] [Indexed: 01/07/2023]
Abstract
For insects, chilling injuries that occur in the absence of freezing are often related to a systemic loss of ion and water balance that leads to extracellular hyperkalemia, cell depolarization and the triggering of apoptotic signalling cascades. The ability of insect ionoregulatory organs (e.g. the Malpighian tubules) to maintain ion balance in the cold has been linked to improved chill tolerance, and many neuroendocrine factors are known to influence ion transport rates of these organs. Injection of micromolar doses of CAPA (an insect neuropeptide) have been previously demonstrated to improve Drosophila cold tolerance, but the mechanisms through which it impacts chill tolerance are unclear, and low doses of CAPA have been previously demonstrated to cause anti-diuresis in insects, including dipterans. Here, we provide evidence that low (femtomolar) and high (micromolar) doses of CAPA impair and improve chill tolerance, respectively, via two different effects on Malpighian tubule ion and water transport. While low doses of CAPA are anti-diuretic, reduce tubule K+ clearance rates and reduce chill tolerance, high doses facilitate K+ clearance from the haemolymph and increase chill tolerance. By quantifying CAPA peptide levels in the central nervous system, we estimated the maximum achievable hormonal titres of CAPA and found further evidence that CAPA may function as an anti-diuretic hormone in Drosophila melanogaster We provide the first evidence of a neuropeptide that can negatively affect cold tolerance in an insect and further evidence of CAPA functioning as an anti-diuretic peptide in this ubiquitous insect model.
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Affiliation(s)
| | - Basma Nazal
- Department of Biology, York University, Toronto, ON, Canada M3J 1P3
| | - Sahr Wali
- Department of Biology, York University, Toronto, ON, Canada M3J 1P3
| | - Gil Y Yerushalmi
- Department of Biology, York University, Toronto, ON, Canada M3J 1P3
| | - Lidiya Misyura
- Department of Biology, York University, Toronto, ON, Canada M3J 1P3
| | - Andrew Donini
- Department of Biology, York University, Toronto, ON, Canada M3J 1P3
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19
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Gáliková M, Dircksen H, Nässel DR. The thirsty fly: Ion transport peptide (ITP) is a novel endocrine regulator of water homeostasis in Drosophila. PLoS Genet 2018; 14:e1007618. [PMID: 30138334 PMCID: PMC6124785 DOI: 10.1371/journal.pgen.1007618] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 09/05/2018] [Accepted: 08/09/2018] [Indexed: 01/07/2023] Open
Abstract
Animals need to continuously adjust their water metabolism to the internal and external conditions. Homeostasis of body fluids thus requires tight regulation of water intake and excretion, and a balance between ingestion of water and solid food. Here, we investigated how these processes are coordinated in Drosophila melanogaster. We identified the first thirst-promoting and anti-diuretic hormone of Drosophila, encoded by the gene Ion transport peptide (ITP). This endocrine regulator belongs to the CHH (crustacean hyperglycemic hormone) family of peptide hormones. Using genetic gain- and loss-of-function experiments, we show that ITP signaling acts analogous to the human vasopressin and renin-angiotensin systems; expression of ITP is elevated by dehydration of the fly, and the peptide increases thirst while repressing excretion, promoting thus conservation of water resources. ITP responds to both osmotic and desiccation stress, and dysregulation of ITP signaling compromises the fly's ability to cope with these stressors. In addition to the regulation of thirst and excretion, ITP also suppresses food intake. Altogether, our work identifies ITP as an important endocrine regulator of thirst and excretion, which integrates water homeostasis with feeding of Drosophila.
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Affiliation(s)
| | | | - Dick R. Nässel
- Department of Zoology, Stockholm University, Stockholm, Sweden
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20
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Yerushalmi GY, Misyura L, Donini A, MacMillan HA. Chronic dietary salt stress mitigates hyperkalemia and facilitates chill coma recovery in Drosophila melanogaster. JOURNAL OF INSECT PHYSIOLOGY 2016; 95:89-97. [PMID: 27642001 DOI: 10.1016/j.jinsphys.2016.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 09/12/2016] [Accepted: 09/13/2016] [Indexed: 06/06/2023]
Abstract
Chill susceptible insects like Drosophila lose the ability to regulate water and ion homeostasis at low temperatures. This loss of hemolymph ion and water balance drives a hyperkalemic state that depolarizes cells, causing cellular injury and death. The ability to maintain ion homeostasis at low temperatures and/or recover ion homeostasis upon rewarming is closely related to insect cold tolerance. We thus hypothesized that changes to organismal ion balance, which can be achieved in Drosophila through dietary salt loading, could alter whole animal cold tolerance phenotypes. We put Drosophila melanogaster in the presence of diets highly enriched in NaCl, KCl, xylitol (an osmotic control) or sucrose (a dietary supplement known to impact cold tolerance) for 24h and confirmed that they consumed the novel food. Independently of their osmotic effects, NaCl, KCl, and sucrose supplementation all improved the ability of flies to maintain K+ balance in the cold, which allowed for faster recovery from chill coma after 6h at 0°C. These supplements, however, also slightly increased the CTmin and had little impact on survival rates following chronic cold stress (24h at 0°C), suggesting that the effect of diet on cold tolerance depends on the measure of cold tolerance assessed. In contrast to prolonged salt stress, brief feeding (1.5h) on diets high in salt slowed coma recovery, suggesting that the long-term effects of NaCl and KCl on chilling tolerance result from phenotypic plasticity, induced in response to a salty diet, rather than simply the presence of the diet in the gut lumen.
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Affiliation(s)
- Gil Y Yerushalmi
- Department of Biology, York University, 4700 Keele St., Toronto M3J 1P3, Canada
| | - Lidiya Misyura
- Department of Biology, York University, 4700 Keele St., Toronto M3J 1P3, Canada
| | - Andrew Donini
- Department of Biology, York University, 4700 Keele St., Toronto M3J 1P3, Canada
| | - Heath A MacMillan
- Department of Biology, York University, 4700 Keele St., Toronto M3J 1P3, Canada.
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21
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Esquivel CJ, Cassone BJ, Piermarini PM. A de novo transcriptome of the Malpighian tubules in non-blood-fed and blood-fed Asian tiger mosquitoes Aedes albopictus: insights into diuresis, detoxification, and blood meal processing. PeerJ 2016; 4:e1784. [PMID: 26989622 PMCID: PMC4793337 DOI: 10.7717/peerj.1784] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/19/2016] [Indexed: 01/17/2023] Open
Abstract
Background. In adult female mosquitoes, the renal (Malpighian) tubules play an important role in the post-prandial diuresis, which removes excess ions and water from the hemolymph of mosquitoes following a blood meal. After the post-prandial diuresis, the roles that Malpighian tubules play in the processing of blood meals are not well described. Methods. We used a combination of next-generation sequencing (paired-end RNA sequencing) and physiological/biochemical assays in adult female Asian tiger mosquitoes (Aedes albopictus) to generate molecular and functional insights into the Malpighian tubules and how they may contribute to blood meal processing (3–24 h after blood ingestion). Results/Discussion. Using RNA sequencing, we sequenced and assembled the first de novo transcriptome of Malpighian tubules from non-blood-fed (NBF) and blood-fed (BF) mosquitoes. We identified a total of 8,232 non-redundant transcripts. The Malpighian tubules of NBF mosquitoes were characterized by the expression of transcripts associated with active transepithelial fluid secretion/diuresis (e.g., ion transporters, water channels, V-type H+-ATPase subunits), xenobiotic detoxification (e.g., cytochrome P450 monoxygenases, glutathione S-transferases, ATP-binding cassette transporters), and purine metabolism (e.g., xanthine dehydrogenase). We also detected the expression of transcripts encoding sodium calcium exchangers, G protein coupled-receptors, and septate junctional proteins not previously described in mosquito Malpighian tubules. Within 24 h after a blood meal, transcripts associated with active transepithelial fluid secretion/diuresis exhibited a general downregulation, whereas those associated with xenobiotic detoxification and purine catabolism exhibited a general upregulation, suggesting a reinvestment of the Malpighian tubules’ molecular resources from diuresis to detoxification. Physiological and biochemical assays were conducted in mosquitoes and isolated Malpighian tubules, respectively, to confirm that the transcriptomic changes were associated with functional consequences. In particular, in vivo diuresis assays demonstrated that adult female mosquitoes have a reduced diuretic capacity within 24 h after a blood meal. Moreover, biochemical assays in isolated Malpighian tubules showed an increase in glutathione S-transferase activity and the accumulation of uric acid (an end product of purine catabolism) within 24 h after a blood meal. Our data provide new insights into the molecular physiology of Malpighian tubules in culicine mosquitoes and reveal potentially important molecular targets for the development of chemical and/or gene-silencing insecticides that would disrupt renal function in mosquitoes.
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Affiliation(s)
- Carlos J Esquivel
- Department of Entomology, The Ohio State University/Ohio Agricultural Research and Development Center , Wooster, OH , United States
| | - Bryan J Cassone
- Department of Biology, Brandon University , Brandon, Manitoba , Canada
| | - Peter M Piermarini
- Department of Entomology, The Ohio State University/Ohio Agricultural Research and Development Center , Wooster, OH , United States
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22
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Egekwu N, Sonenshine DE, Garman H, Barshis DJ, Cox N, Bissinger BW, Zhu J, M Roe R. Comparison of synganglion neuropeptides, neuropeptide receptors and neurotransmitter receptors and their gene expression in response to feeding in Ixodes scapularis (Ixodidae) vs. Ornithodoros turicata (Argasidae). INSECT MOLECULAR BIOLOGY 2016; 25:72-92. [PMID: 26783017 DOI: 10.1111/imb.12202] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Illumina GAII high-throughput sequencing was used to compare expressed genes for female synganglion neuropeptides, neuropeptide receptors and neurotransmitter receptors of the soft tick Ornithodoros turicata with the hard tick Ixodes scapularis. Gene ontology molecular level three mapping revealed no significant differences amongst the same categories represented in O. turicata and I. scapularis. Transcripts predicting 22 neuropeptides or their receptors in the O. turicata synganglion were similar to annotations for 23 neuropeptides or receptors previously identified from I scapularis, with minor exceptions. A transcript predicting ecdysis triggering hormone receptor was identified in O. turicata; transcripts encoding for proprotein convertase and glycoprotein B were identified in both species. Transcripts predicting the same neurotransmitter receptors were found in the synganglion of both species. Gene expression of the transcripts showed numerous differences in response to feeding. Major differences were observed in expression of genes believed important in regulating slow vs. rapid feeding, blood water elimination, cuticle synthesis plasticity and in signalling reproductive activity. Although the glutamate receptor was strongly upregulated in both species, the gamma aminobutyric acid receptor, which inhibits glutamate, was upregulated significantly only in I. scapularis. These differences are consistent with the slow vs. rapid action of the pharyngeal pump in the two species.
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Affiliation(s)
- N Egekwu
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - D E Sonenshine
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - H Garman
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - D J Barshis
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - N Cox
- Eastern Virginia Medical School, Norfolk, VA, USA
| | - B W Bissinger
- Tyra Tech, R&D, Repellents & Animal Health, Morrisville, NC, USA
| | - J Zhu
- Department of Entomology, North Carolina State University, Raleigh, NC, USA
| | - R M Roe
- Department of Entomology, North Carolina State University, Raleigh, NC, USA
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23
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Audsley N, Down RE. G protein coupled receptors as targets for next generation pesticides. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 67:27-37. [PMID: 26226649 DOI: 10.1016/j.ibmb.2015.07.014] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 07/13/2015] [Accepted: 07/17/2015] [Indexed: 06/04/2023]
Abstract
There is an on-going need for the discovery and development of new pesticides due to the loss of existing products through the continuing development of resistance, the desire for products with more favourable environmental and toxicological profiles and the need to implement the principles of integrated pest management. Insect G protein coupled receptors (GPCRs) have important roles in modulating biology, physiology and behaviour, including reproduction, osmoregulation, growth and development. Modifying normal receptor function by blocking or over stimulating its actions may either result in the death of a pest or disrupt its normal fitness or reproductive capacity to reduce pest populations. Hence GPCRs offer potential targets for the development of next generation pesticides providing opportunities to discover new chemistries for invertebrate pest control. Such receptors are important targets for pharmaceutical drugs, but are under-exploited by the agro-chemical industry. The octopamine receptor agonists are the only pesticides with a recognized mode of action, as described in the classification scheme developed by the Insecticide Resistance Action Committee, that act via a GPCR. The availability of sequenced insect genomes has facilitated the characterization of insect GPCRs, but the development and utilization of screening assays to identify lead compounds has been slow. Various studies using knock-down technologies or applying the native ligands and/or neuropeptide analogues to pest insects in vivo, have however demonstrated that modifying normal receptor function can have an insecticidal effect. This review presents examples of potential insect neuropeptide receptors that are potential targets for lead compound development, using case studies from three representative pest species, Tribolium castaneum, Acyrthosiphon pisum, and Drosophila suzukii. Functional analysis studies on T. castaneum suggest that GPCRs involved in growth and development (eclosion hormone, ecdysis triggering hormone and crustacean cardioacceleratory peptide receptors) as well as the dopamine-2 like, latrophilin-like, starry night, frizzled-like, methuselah-like and the smoothened receptors may be suitable pesticide targets. From in vivo studies using native ligands and peptide analogues, receptors which appear to have a role in the regulation of feeding in the pea aphid, such as the PISCF-allatostatin and the various "kinin" receptors, are also potential targets. In Drosophila melanogaster various neuropeptides and their signalling pathways have been studied extensively. This may provide insights into potential pesticide targets that could be exploited in D. suzukii. Examples include the sex peptide receptor, which is involved in reproduction and host seeking behaviours, and those responsible for osmoregulation such as the diuretic hormone receptors. However the neuropeptides and their receptors in insects are often poorly characterized, especially in pest species. Although data from closely related species may be transferable (e.g. D. melanogaster to D. suzukii), peptides and receptors may have different roles in different insects, and hence a target in one insect may not be appropriate in another. Hence fundamental knowledge of the roles and functions of receptors is vital for development to proceed.
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24
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Han B, Fang Y, Feng M, Hu H, Qi Y, Huo X, Meng L, Wu B, Li J. Quantitative Neuropeptidome Analysis Reveals Neuropeptides Are Correlated with Social Behavior Regulation of the Honeybee Workers. J Proteome Res 2015; 14:4382-93. [DOI: 10.1021/acs.jproteome.5b00632] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Bin Han
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Yu Fang
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Mao Feng
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Han Hu
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Yuping Qi
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Xinmei Huo
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Lifeng Meng
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Bin Wu
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
| | - Jianke Li
- Institute of Apicultural
Research/Key Laboratory of Pollinating Insect Biology, Ministry of
Agriculture, Chinese Academy of Agricultural Sciences, No. 1 Beigou
Xiangshan, Beijing 100093, China
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25
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Audsley N, Down RE, Isaac RE. Genomic and peptidomic analyses of the neuropeptides from the emerging pest, Drosophila suzukii. Peptides 2015; 68:33-42. [PMID: 25158078 DOI: 10.1016/j.peptides.2014.08.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/15/2014] [Accepted: 08/15/2014] [Indexed: 01/09/2023]
Abstract
Drosophila suzukii is a highly polyphagous invasive pest which has been recently introduced into Europe and North America, where it is causing severe economic losses through larval infestations of stone and berry fruits. The peptidome of the selected nervous tissues of adult D. suzukii was investigated as a first step in identifying potential targets for the development of novel insecticides. Through in silico analyses of the D. suzukii genome databases 28 neuropeptide families, comprising more than 70 predicted peptides were identified. Using a combination of liquid chromatography and mass spectrometry of tissue extracts, 33 predicted peptides, representing 15 different peptide families were identified by their molecular masses and a total of 17 peptide sequences were confirmed by ion fragmentation. A comparison between the peptides and precursors of D. suzukii and D. melanogaster shows they are highly conserved, with differences only identified in the amino acid sequences of the peptides encoded in the FMRFamide, hugin and ecydysis triggering hormone precursors. All other peptides predicted and identified from D. suzukii appear to be identical to those previously characterized from D. melanogaster. Adipokinetic hormone was only identified in the corpus cardiacum, other peptides present included short neuropeptide F, a pyrokinin and myosuppressin, the latter of which was the only peptide identified from the crop nerve bundle. Peptides present in extracts of the brain and/or thoracico-abdominal ganglion included allatostatins, cardioacceleratory peptide 2b, corazonin, extended FMRFamides, pyrokinins, myoinihibitory peptides, neuropeptide-like precursor 1, SIFamide, short neuropeptide F, kinin, sulfakinins and tachykinin related peptides.
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Affiliation(s)
- Neil Audsley
- The Food and Environmental Research Agency, Sand Hutton, York YO41 1LZ, UK.
| | - Rachel E Down
- The Food and Environmental Research Agency, Sand Hutton, York YO41 1LZ, UK
| | - R Elwyn Isaac
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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26
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MacMillan HA, Andersen JL, Loeschcke V, Overgaard J. Sodium distribution predicts the chill tolerance of Drosophila melanogaster raised in different thermal conditions. Am J Physiol Regul Integr Comp Physiol 2015; 308:R823-31. [DOI: 10.1152/ajpregu.00465.2014] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 03/05/2015] [Indexed: 11/22/2022]
Abstract
Many insects, including the model holometabolous insect Drosophila melanogaster, display remarkable plasticity in chill tolerance in response to the thermal environment experienced during development or as adults. At low temperatures, many insects lose the ability to regulate Na+ balance, which is suggested to cause a secondary loss of hemolymph water to the tissues and gut lumen that concentrates the K+ remaining in the hemolymph. The resultant increase in extracellular [K+] inhibits neuromuscular excitability and is proposed to cause cellular apoptosis and injury. The present study investigates whether and how variation in chill tolerance induced through developmental and adult cold acclimation is associated with changes in Na+, water, and K+ balance. Developmental and adult cold acclimation improved the chilling tolerance of D. melanogaster in an additive manner. In agreement with the proposed model, these effects were intimately related to differences in Na+ distribution prior to cold exposure, such that chill-tolerant flies had low hemolymph [Na+], while intracellular [Na+] was similar among treatment groups. The low hemolymph Na+ of cold-acclimated flies allowed them to maintain hemolymph volume, prevent hyperkalemia, and avoid injury following chronic cold exposure. These findings extend earlier observations of hemolymph volume disruption during cold exposure to the most ubiquitous model insect ( D. melanogaster), highlight shared mechanisms of developmental and adult thermal plasticity and provide strong support for ionoregulatory failure as a central mechanism of insect chill susceptibility.
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Affiliation(s)
- Heath A. MacMillan
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus C, Denmark; and
| | - Jonas L. Andersen
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus C, Denmark; and
| | - Volker Loeschcke
- Genetics, Ecology and Evolution, Department of Bioscience, Aarhus University, Aarhus C, Denmark
| | - Johannes Overgaard
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus C, Denmark; and
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27
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Davies SA, Cabrero P, Overend G, Aitchison L, Sebastian S, Terhzaz S, Dow JAT. Cell signalling mechanisms for insect stress tolerance. ACTA ACUST UNITED AC 2014; 217:119-28. [PMID: 24353211 DOI: 10.1242/jeb.090571] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Insects successfully occupy most environmental niches and this success depends on surviving a broad range of environmental stressors including temperature, desiccation, xenobiotic, osmotic and infection stress. Epithelial tissues play key roles as barriers between the external and internal environments and therefore maintain homeostasis and organismal tolerance to multiple stressors. As such, the crucial role of epithelia in organismal stress tolerance cannot be underestimated. At a molecular level, multiple cell-specific signalling pathways including cyclic cAMP, cyclic cGMP and calcium modulate tissue, and hence, organismal responses to stress. Thus, epithelial cell-specific signal transduction can be usefully studied to determine the molecular mechanisms of organismal stress tolerance in vivo. This review will explore cell signalling modulation of stress tolerance in insects by focusing on cell signalling in a fluid transporting epithelium--the Malpighian tubule. Manipulation of specific genes and signalling pathways in only defined tubule cell types can influence the survival outcome in response to multiple environmental stressors including desiccation, immune, salt (ionic) and oxidative stress, suggesting that studies in the genetic model Drosophila melanogaster may reveal novel pathways required for stress tolerance.
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Affiliation(s)
- Shireen A Davies
- Institute of Molecular Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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28
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Hine RM, Rouhier MF, Park ST, Qi Z, Piermarini PM, Beyenbach KW. The excretion of NaCl and KCl loads in mosquitoes. 1. Control data. Am J Physiol Regul Integr Comp Physiol 2014; 307:R837-49. [PMID: 25056103 DOI: 10.1152/ajpregu.00105.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The handling of Na(+) and K(+) loads was investigated in isolated Malpighian tubules and in whole mosquitoes of Aedes aegypti. Isolated Malpighian tubules bathed in Na(+)-rich Ringer solution secreted Na(+)-rich fluid, and tubules bathed in K(+)-rich Ringer solution secreted K(+)-rich fluid. Upon Na(+) loading the hemolymph, the mosquito removed 77% the injected Na(+) within the next 30 min. The rapid onset and magnitude of this diuresis and the excretion of more Na(+) than can be accounted for by tubular secretion in vitro is consistent with the release of the calcitonin-like diuretic hormone in the mosquito to remove the Na(+) load from the hemolymph. Downstream, K(+) was reabsorbed with water in the hindgut, which concentrated Na(+) in excreted urine hyperosmotic to the hemolymph. Upon K(+) loading the hemolymph, the mosquito took 2 h to remove 100% of the injected K(+) from the hemolymph. The excretion of K(+)-rich isosmotic urine was limited to clearing the injected K(+) from the hemolymph with a minimum of Cl(-) and water. As a result, 43.3% of the injected Cl(-) and 48.1% of the injected water were conserved. The cation retained in the hemolymph with Cl(-) was probably N-methyl-d-glucamine, which replaced Na(+) in the hemolymph injection of the K(+) load. Since the tubular secretion of K(+) accounts for the removal of the K(+) load from the hemolymph, the reabsorption of K(+), Na(+), Cl(-), and water must be inhibited in the hindgut. The agents mediating this inhibition are unknown.
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Affiliation(s)
- Rebecca M Hine
- Department of Biomedical Sciences, Cornell University, Ithaca, New York
| | - Matthew F Rouhier
- Department of Entomology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio; and
| | | | - Zhijun Qi
- Institute of Pesticide Science, Northwestern Agricultural and Forestry University, Yangling, Shaanxi, China
| | - Peter M Piermarini
- Department of Entomology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio; and
| | - Klaus W Beyenbach
- Department of Biomedical Sciences, Cornell University, Ithaca, New York;
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29
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Piermarini PM, Calkins TL. Evidence for intercellular communication in mosquito renal tubules: a putative role of gap junctions in coordinating and regulating the rapid diuretic effects of neuropeptides. Gen Comp Endocrinol 2014; 203:43-8. [PMID: 24316302 PMCID: PMC4045701 DOI: 10.1016/j.ygcen.2013.11.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/23/2013] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
Abstract
Adult female mosquitoes require a blood meal from a vertebrate host to successfully reproduce. During a single blood feeding, a female may ingest more than the equivalent of her own body mass, resulting in an acute stress to osmotic and ionic homeostasis. In response to this stress, the renal (Malpighian) tubules mediate a rapid diuresis that commences as soon as blood is ingested. The diuresis is regulated by neuropeptides (e.g., kinins, calcitonin-like peptide) that act on receptors in the Malpighian tubule epithelium. Interestingly, the expression of these receptors is discontinuous throughout the epithelium, which raises the question as to how Malpighian tubules mount such a rapid and synchronized response to neuropeptide stimulation. Here we propose a hypothesis that gap junctions functionally couple the epithelial cells of Malpighian tubules, resulting in a coordinated physiological response to the binding of neuropeptides. We review recent, relevant literature on the electrophysiology, physiology, and molecular biology of mosquito Malpighian tubules that indicate the presence of gap junctions in the epithelium. We also provide new physiological and immunochemical data that are consistent with the proposed hypothesis.
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Affiliation(s)
- Peter M Piermarini
- Department of Entomology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA.
| | - Travis L Calkins
- Department of Entomology, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA
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30
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Abstract
Corticotrophin-releasing hormone (CRH) is the pivotal neuroendocrine peptide hormone associated with the regulation of the stress response in vertebrates. However, CRH-like peptides are also found in a number of invertebrate species. The origin of this peptide can be traced to a common ancestor of lineages leading to chordates and to arthropods, postulated to occur some 500 million years ago. Evidence indicates the presence of a single CRH-like receptor and a soluble binding protein system that acted to transduce and regulate the actions of the early CRH peptide. In vertebrates, genome duplications led to the divergence of CRH receptors into CRH1 and CRH2 forms in tandem with the development of four paralogous ligand lineages that included CRH; urotensin I/urocortin (Ucn), Ucn2 and Ucn3. In addition, taxon-specific genome duplications led to further local divergences in CRH ligands and receptors. Functionally, the CRH ligand-receptor system evolved initially as a molecular system to integrate early diuresis and nutrient acquisition. As multicellular organisms evolved into more complex forms, this ligand-receptor system became integrated with the organismal stress response to coordinate homoeostatic challenges with internal energy usage. In vertebrates, CRH and the CRH1 receptor became associated with the hypothalamo-pituitary-adrenal/interrenal axis and the initial stress response, whereas the CRH2 receptor was selected to play a greater role in diuresis, nutrient acquisition and the latter aspects of the stress response.
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Affiliation(s)
- David A Lovejoy
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
| | - Belinda S W Chang
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, CanadaDepartment of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
| | - Nathan R Lovejoy
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
| | - Jon del Castillo
- Department of Cell and Systems BiologyUniversity of Toronto, 25 Harbord Street, Toronto, Ontario, Canada L4A IK6Department of Ecology and EvolutionUniversity of Toronto, Toronto, Ontario, CanadaDepartment of Life SciencesUniversity of Toronto Scarborough, Toronto, Ontario, Canada
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31
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Larsen EH, Deaton LE, Onken H, O'Donnell M, Grosell M, Dantzler WH, Weihrauch D. Osmoregulation and Excretion. Compr Physiol 2014; 4:405-573. [DOI: 10.1002/cphy.c130004] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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32
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Robertson L, Donini A, Lange AB. K+ absorption by locust gut and inhibition of ileal K+ and water transport by FGLamide allatostatins. J Exp Biol 2014; 217:3377-85. [DOI: 10.1242/jeb.101774] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Abstract
The Scanning Ion-Selective Electrode Technique (SIET) was utilized for the first time in Locusta migratoria to characterize K+ transport along the digestive tract and to determine the effect of two locust FGLamide allatostatins (FGLa/ASTs) on K+ transport: a previously sequenced FGLa/AST from Schistocerca gregaria (Scg-AST-6; ARPYSFGL-NH2) and a newly sequenced FGLa/AST from L. migratoria (Locmi-FGLa/AST-2; LPVYNFGL-NH2). Regional differences in K+ fluxes along the gut were evident, where K+ efflux in vitro (or absorption into the hemolymph in vivo) was greatest at the anterior ileum, and lowest at the colon. Ileal K+ efflux was inhibited by both Scg-AST-6 and Locmi-FGLa/AST-2, with maximal inhibition at 10-10 and 10-11 M, respectively. Both FGLa/ASTs also inhibited cAMP-stimulated K+ efflux from the ileum. Locmi-FGLa/AST-2 also inhibited efflux of water across the ileum. Locusts are terrestrial insects living in dry climates, risking desiccation and making water conservation a necessity. The results suggest that FGLa/ASTs may be acting as diuretics by increasing K+ excretion and therefore increasing water excretion. Thus, it is likely that FGLa/ASTs are involved in the control of hemolymph water and ion levels during feeding and digestion, to help the locust deal with the excess K+ load (and subsequently fluid) when the meal is processed.
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33
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Kwon H, Pietrantonio PV. Calcitonin receptor 1 (AedaeGPCRCAL1) hindgut expression and direct role in myotropic action in females of the mosquito Aedes aegypti (L.). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:588-593. [PMID: 23523607 DOI: 10.1016/j.ibmb.2013.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/07/2013] [Accepted: 03/08/2013] [Indexed: 06/02/2023]
Abstract
In anautogenous mosquitoes such as Aedes aegypti females the calcitonin-like diuretic hormone 31 (DH₃₁) stimulates natriuretic fluid excretion from the Malpighian tubules (MTs) after a blood meal. We previously cloned and functionally characterized AedaeGPCRcal1 from A. aegypti, the ortholog of the Drosophila melanogaster DH₃₁ receptor and immunolocalized it in the MTs. However, localization of the calcitonin receptor-like receptor 1 (GPCRCAL1) in the hindgut of any insect is unknown, and specifically, knowledge on its role in hindgut contraction in response to Aedae-DH₃₁ peptide is lacking. We analyzed the expression of AedaeGPCRCAL1 in hindgut by western blot and immunohistochemistry, and evaluated its role in hindgut contractility by application of Aedae-DH₃₁ before and after receptor RNA interference (RNAi). The receptor was detected as a 73 kDa band in western blots of hindgut and immunofluorescence revealed the receptor was expressed in hindgut circular and longitudinal muscles but not in the hindgut epithelial cells. In vitro, incubation in 1 μM solution of Aedae-DH₃₁ peptide significantly increased the hindgut contraction frequency in normal mosquitoes. Hindguts from females treated with AedaeGPCRcal1 dsRNA and incubated with DH₃₁ showed a reduction of 50% percent in their contraction frequency with respect to controls. These results suggest that DH₃₁ hormone released from the brain post-blood meal has a direct and coordinative action on the excretory system, MTs and hindgut, by which AedaeGPCRCAL1 signaling stimulates MT primary urine secretion and hindgut contraction resulting in rapid postprandial fluid excretion.
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Affiliation(s)
- Hyeogsun Kwon
- Department of Entomology, Texas A&M University, College Station, TX 77843-2475, USA
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Audsley N, Jensen D, Schooley DA. Signal transduction for Schistocerca gregaria ion transport peptide is mediated via both cyclic AMP and cyclic GMP. Peptides 2013; 41:74-80. [PMID: 23147644 DOI: 10.1016/j.peptides.2012.11.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 11/01/2012] [Accepted: 11/01/2012] [Indexed: 10/27/2022]
Abstract
The second messengers involved in the signal transduction for Schistocerca gregaria, ion transport peptide (Schgr-ITP) that regulates ion and fluid transport across the ileum of the desert locust S. gregaria, were measured using competitive enzyme-linked immunosorbent assays (ELISAs). Synthetic Schgr-ITP elevates intracellular levels of both cyclic AMP and cyclic GMP, measured over a 15 min period in the presence of 3-isobutyl-1-methylxanthine, in a dose-dependent manner. Furthermore, crude corpora cardiaca (CC) extracts elevate intracellular cyclic AMP levels 2-fold greater than Schgr-ITP, suggesting that factors present in the CC, other than Schgr-ITP, also act via this second messenger. These results suggest that the interaction of Schgr-ITP with two separate receptors, most likely a G-protein coupled receptor and a membrane bound guanylate cyclase, elevates intracellular levels of cyclic AMP and cyclic GMP to regulate ion and fluid transport across the locust ileum. Cyclic AMP stimulates Cl(-), K(+) and Na(+) reabsorption, whereas secretion of H(+) into the lumen of the ileum is most likely mediated via cyclic GMP. Cyclic GMP also stimulates Cl(-) uptake in a similar manner to cyclic AMP. The measurement of tissue (central nervous system) levels of Schgr-ITP using an indirect ELISA confirms that the peptide is only present in the locust brain and the CC. The amounts present are greatest in the CC, where the peptide is presumably stored for release into the hemolymph when locusts feed.
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Affiliation(s)
- Neil Audsley
- The Food and Environment Research Agency, Sand Hutton, York, UK.
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35
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Cabrero P, Richmond L, Nitabach M, Davies SA, Dow JAT. A biogenic amine and a neuropeptide act identically: tyramine signals through calcium in Drosophila tubule stellate cells. Proc Biol Sci 2013; 280:20122943. [PMID: 23446525 PMCID: PMC3619477 DOI: 10.1098/rspb.2012.2943] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Insect osmoregulation is subject to highly sophisticated endocrine control. In Drosophila, both Drosophila kinin and tyramine act on the Malpighian (renal) tubule stellate cell to activate chloride shunt conductance, and so increase the fluid production rate. Drosophila kinin is known to act through intracellular calcium, but the mode of action of tyramine is not known. Here, we used a transgenically encoded GFP::apoaequorin translational fusion, targeted to either principal or stellate cells under GAL4/UAS control, to demonstrate that tyramine indeed acts to raise calcium in stellate, but not principal cells. Furthermore, the EC(50) tyramine concentration for half-maximal activation of the intracellular calcium signal is the same as that calculated from previously published data on tyramine-induced increase in chloride flux. In addition, tyramine signalling to calcium is markedly reduced in mutants of NorpA (a phospholipase C) and itpr, the inositol trisphosphate receptor gene, which we have previously shown to be necessary for Drosophila kinin signalling. Therefore, tyramine and Drosophila kinin signals converge on phospholipase C, and thence on intracellular calcium; and both act to increase chloride shunt conductance by signalling through itpr. To test this model, we co-applied tyramine and Drosophila kinin, and showed that the calcium signals were neither additive nor synergistic. The two signalling pathways thus represent parallel, independent mechanisms for distinct tissues (nervous and epithelial) to control the same aspect of renal function.
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Affiliation(s)
- Pablo Cabrero
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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Li C, Chen M, Sang M, Liu X, Wu W, Li B. Comparative genomic analysis and evolution of family-B G protein-coupled receptors from six model insect species. Gene 2013; 519:1-12. [PMID: 23428791 DOI: 10.1016/j.gene.2013.01.061] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 12/21/2012] [Accepted: 01/30/2013] [Indexed: 10/27/2022]
Abstract
Family-B G protein-coupled receptors (GPCR-Bs) play vital roles in many biological processes, including growth, development and reproduction. However, the evolution and function of GPCR-Bs have been poorly understood in insects. We have identified 87 GPCR-Bs from six model insect species, 20 from Tribolium castaneum, 9 from Apis mellifera, 11 from Bombyx mori, 9 from Acyrthosiphon pisum, 14 from Anopheles gambiae and 24 from Drosophila melanogaster. 22 of them were reported in this study for the first time. Phylogenetic analysis revealed that there are three kinds of evolutionary patterns that occurred among GPCR-Bs during insect evolution: one-to-one orthologous relationships, species-specific expansion and episodic duplication or loss in certain insect lineages. A striking finding was the discovery of a parathyroid hormone receptor like gene (pthrl) in invertebrates, which was independently duplicated in vertebrates and invertebrates, whereas this gene was lost at least twice during insect evolution. These results indicate that PTHRL is possibly divergent in the functions between mammals and insects. The information of family-B GPCRs in nondrosophiline insects has been established, and will promote the further study on the function of these GPCRs and deorphanization of them. On the other hand, this study provides us with multiple function of GPCR-Bs in differential organisms, which will be also the potential attacking targets for new pesticides and drugs.
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Affiliation(s)
- Chengjun Li
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
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Ionescu A, Donini A. AedesCAPA-PVK-1 displays diuretic and dose dependent antidiuretic potential in the larval mosquito Aedes aegypti (Liverpool). JOURNAL OF INSECT PHYSIOLOGY 2012; 58:1299-1306. [PMID: 22820035 DOI: 10.1016/j.jinsphys.2012.07.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 06/26/2012] [Accepted: 07/02/2012] [Indexed: 06/01/2023]
Abstract
This study reveals that AedesCAPA-PVK-1 (GPTVGLFAFPRV-NH(2)) inhibits basal and serotonin stimulated fluid secretion in the Malpighian tubules of larval Aedes aegypti at femtomolar concentrations. Conversely 10(-4)moll(-1) of the peptide stimulated fluid secretion rates. The diuretic effects of 10(-4)moll(-1)AedesCAPA-PVK-1 and antidiuretic effects of 10(-15)moll(-1)AedesCAPA-PVK-1 were abolished by protein kinase A (PKA) and protein kinase G (PKG) inhibition, respectively. Similar to the peptide, 10(-3)moll(-1) cGMP stimulated fluid secretion but doses in the micromolar to nanomolar range inhibited fluid secretion of the Malpighian tubules. Stimulatory effects of cGMP were abolished by PKA inhibition and inhibitory effects of cGMP were abolished by PKG inhibition. Furthermore, the nitric oxide synthase inhibitor l-NAME attenuated the inhibitory effects of AedesCAPA-PVK-1 but did not affect inhibition by cGMP. Based on the results we propose that AedesCAPA-PVK-1 inhibits fluid secretion rates of larval Malpighian tubules via the NOS/cGMP/PKG pathway and that high doses of the peptide lead to diuresis through the cGMP mediated activation of PKA.
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Affiliation(s)
- Adrian Ionescu
- Department of Biology, York University, 4700 Keele Street, Toronto, ON, Canada M3J 1P3
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De Loof A, Lindemans M, Liu F, De Groef B, Schoofs L. Endocrine archeology: do insects retain ancestrally inherited counterparts of the vertebrate releasing hormones GnRH, GHRH, TRH, and CRF? Gen Comp Endocrinol 2012; 177:18-27. [PMID: 22402582 DOI: 10.1016/j.ygcen.2012.02.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 01/20/2012] [Accepted: 02/03/2012] [Indexed: 11/28/2022]
Abstract
Vertebrate releasing hormones include gonadotropin releasing hormone (GnRH), growth hormone releasing hormone (GHRH), corticotropin releasing hormone (CRF), and thyrotropin-releasing hormone (TRH). They are synthesized in the hypothalamus and stimulate the release of pituitary hormones. Here we review the knowledge on hormone releasing systems in the protostomian lineage. We address the question: do insects have peptides that may be phylogenetically related to an ancestral GnRH, GHRH, TRH, and CRF? Such endocrine archeology has become possible thanks to the growing list of fully sequenced genomes as well as to the continuously improving bioinformatic tool set. It has recently been shown that the ecdysozoan (nematodes and arthropods) adipokinetic hormones (AKHs), the lophotrochozoan (annelids and mollusks) GnRHs as well as the protochordate GnRHs are structurally related. The adipokinetic hormone precursor-related peptides (APRPs), in locusts encoded by the same gene that contains the AKH-coding region, have been forwarded as the structural counterpart of GHRH of vertebrates. CRF is relatively well conserved in insects, in which it functions as a diuretic hormone. Members of TRH-receptor family seem to have been conserved in some arthropods, but other elements of the thyroid hormone signaling system are not. A challenging idea is that in insects the functions of the thyroid hormones were taken over by juvenile hormone (JH). Our reconstruction suggests that, perhaps, the ancestral releasing hormone precursors played a role in controlling energy metabolism and water balance, and that releasing hormone functions as present in extant vertebrates were probably secondarily acquired.
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Affiliation(s)
- Arnold De Loof
- Functional Genomics and Proteomics Group, Department of Biology, KU Leuven-University of Leuven, Belgium.
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Paluzzi JPV. Anti-diuretic factors in insects: the role of CAPA peptides. Gen Comp Endocrinol 2012; 176:300-8. [PMID: 22226757 DOI: 10.1016/j.ygcen.2011.12.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 12/13/2011] [Accepted: 12/17/2011] [Indexed: 10/14/2022]
Abstract
Insects have adapted to live in a wide variety of habitats and utilize an array of feeding strategies that present challenges to their ability to maintain osmotic balance. Regardless of the feeding strategy, water and ion levels within the haemolymph (insect blood) are maintained within a narrow range. This homeostasis involves the action of a variety of tissues, but is often chiefly regulated by the excretory system. Until recently, most research on the hormonal control of the excretory tissues has focused on factors known to have diuretic activities. In this mini-review, the current state of knowledge on anti-diuretic factors in insects will be discussed with a particular emphasis on the CAPA peptides in the blood-feeding Chagas' disease vector, Rhodnius prolixus.
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Affiliation(s)
- Jean-Paul V Paluzzi
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada L8S 4K1.
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Beyenbach KW, Piermarini PM. Transcellular and paracellular pathways of transepithelial fluid secretion in Malpighian (renal) tubules of the yellow fever mosquito Aedes aegypti. Acta Physiol (Oxf) 2011; 202:387-407. [PMID: 20946239 PMCID: PMC3032036 DOI: 10.1111/j.1748-1716.2010.02195.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Isolated Malpighian tubules of the yellow fever mosquito secrete NaCl and KCl from the peritubular bath to the tubule lumen via active transport of Na(+) and K(+) by principal cells. Lumen-positive transepithelial voltages are the result. The counter-ion Cl(-) follows passively by electrodiffusion through the paracellular pathway. Water follows by osmosis, but specific routes for water across the epithelium are unknown. Remarkably, the transepithelial secretion of NaCl, KCl and water is driven by a H(+) V-ATPase located in the apical brush border membrane of principal cells and not the canonical Na(+), K(+) -ATPase. A hypothetical cation/H(+) exchanger moves Na(+) and K(+) from the cytoplasm to the tubule lumen. Also remarkable is the dynamic regulation of the paracellular permeability with switch-like speed which mediates in part the post-blood-meal diuresis in mosquitoes. For example, the blood meal the female mosquito takes to nourish her eggs triggers the release of kinin diuretic peptides that (i) increases the Cl(-) conductance of the paracellular pathway and (ii) assembles V(1) and V(0) complexes to activate the H(+) V-ATPase and cation/H(+) exchange close by. Thus, transcellular and paracellular pathways are both stimulated to quickly rid the mosquito of the unwanted salts and water of the blood meal. Stellate cells of the tubule appear to serve a metabolic support role, exporting the HCO(3)(-) generated during stimulated transport activity. Septate junctions define the properties of the paracellular pathway in Malpighian tubules, but the proteins responsible for the permselectivity and barrier functions of the septate junction are unknown.
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Affiliation(s)
- K W Beyenbach
- Department of Biomedical Sciences, VRT 8004, Cornell University, Ithaca, NY, USA.
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Stress Tolerance of Bed Bugs: A Review of Factors That Cause Trauma to Cimex lectularius and C. Hemipterus. INSECTS 2011; 2:151-72. [PMID: 26467619 PMCID: PMC4553455 DOI: 10.3390/insects2020151] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 03/26/2011] [Accepted: 04/20/2011] [Indexed: 11/16/2022]
Abstract
Recent emergence of bed bugs (Cimex spp.) has prompted a significant expansion of research devoted to this pest. The ability to survive and recover from stress has significant implications on the distribution and survival of insects, and bed bugs are no exception. Research on bed bug stress tolerance has shown considerable progress and necessitates a review on this topic. Bed bugs have an extraordinary ability to resist dehydration between bloodmeals, and this represents a critical factor allowing their prolonged survival when no host is available. High relative humidities are detrimental to bed bugs, leading to reduced survival in comparison to those held at lower relative humidities. Continual exposure of bed bugs, eggs and mobile stages, to temperatures below freezing and short term exposure (=1 h) to temperatures below -16 to -18 °C results in mortality. The upper thermal limit for short term exposure of eggs, nymphs and adults is between 40-45 °C for the common (Cimex lectularius) and tropical (C. hemipterus) bed bugs. Long-term exposure to temperatures above 35 °C results in significant reduction in survival of mobile bed bugs. Eggs for C. lectularius and C. hemipterus are no longer viable when held below 10 °C or above 37 °C throughout embryogenesis. Blood feeding, although necessary for survival and reproduction, is discussed as a stress due to thermal and osmotic fluctuations that result from ingesting a warm bloodmeal from a vertebrate host. Cold, heat, water stress and blood feeding prompted the expression of heat shock proteins (Hsps). Pesticide application is a common human-induced stress for urban pests, and recent studies have documented pesticide resistance in many bed bug populations. High levels of traumatic insemination (mating) of bed bugs has been linked to reduced survival and fecundity along with possibly exposing individuals to microbial infections after cuticular penetration by the paramere (=male reproductive organ), thus represents a form of sexual stress. Additionally, less common stress types such as microbial infections that have been documented in bed bugs will be discussed. Overall, this review provides a current update of research related to bed bug stress tolerance and how their ability to resist stressful conditions has lead to their expansion and proliferation.
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Jonusaite S, Kelly SP, Donini A. The physiological response of larval Chironomus riparius (Meigen) to abrupt brackish water exposure. J Comp Physiol B 2010; 181:343-52. [DOI: 10.1007/s00360-010-0526-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 10/14/2010] [Accepted: 10/17/2010] [Indexed: 10/18/2022]
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Dow JAT, Romero MF. Drosophila provides rapid modeling of renal development, function, and disease. Am J Physiol Renal Physiol 2010; 299:F1237-44. [PMID: 20926630 DOI: 10.1152/ajprenal.00521.2010] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The evolution of specialized excretory cells is a cornerstone of the metazoan radiation, and the basic tasks performed by Drosophila and human renal systems are similar. The development of the Drosophila renal (Malpighian) tubule is a classic example of branched tubular morphogenesis, allowing study of mesenchymal-to-epithelial transitions, stem cell-mediated regeneration, and the evolution of a glomerular kidney. Tubule function employs conserved transport proteins, such as the Na(+), K(+)-ATPase and V-ATPase, aquaporins, inward rectifier K(+) channels, and organic solute transporters, regulated by cAMP, cGMP, nitric oxide, and calcium. In addition to generation and selective reabsorption of primary urine, the tubule plays roles in metabolism and excretion of xenobiotics, and in innate immunity. The gene expression resource FlyAtlas.org shows that the tubule is an ideal tissue for the modeling of renal diseases, such as nephrolithiasis and Bartter syndrome, or for inborn errors of metabolism. Studies are assisted by uniquely powerful genetic and transgenic resources, the widespread availability of mutant stocks, and low-cost, rapid deployment of new transgenics to allow manipulation of renal function in an organotypic context.
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Affiliation(s)
- Julian A T Dow
- Institute of Cell, Molecular, and Systems Biology, College of Medical, Veterinary, and Life Sciences, Univ. of Glasgow, Glasgow G12 8QQ, UK.
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Benoit JB, Denlinger DL. Meeting the challenges of on-host and off-host water balance in blood-feeding arthropods. JOURNAL OF INSECT PHYSIOLOGY 2010; 56:1366-76. [PMID: 20206630 PMCID: PMC2918697 DOI: 10.1016/j.jinsphys.2010.02.014] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 02/08/2010] [Accepted: 02/09/2010] [Indexed: 05/26/2023]
Abstract
In this review, we describe water balance requirements of blood-feeding arthropods, particularly contrasting dehydration tolerance during the unfed, off-host state and the challenges of excess water that accompany receipt of the bloodmeal. Most basic water balance characteristics during the off-host stage are applicable to other terrestrial arthropods, as well. A well-coordinated suite of responses enable arthropods to conserve water resources, enhance their desiccation tolerance, and increase their water supplies by employing a diverse array of molecular, structural and behavioral responses. Water loss rates during the off-host phase are particularly useful for generating a scheme to classify vectors according to their habitat requirements for water, thus providing a convenient tool with potential predictive power for defining suitable current and future vector habitats. Blood-feeding elicits an entirely different set of challenges as the vector responds to overhydration by quickly increasing its rate of cuticular water loss and elevating the rate of diuresis to void excess water and condense the bloodmeal. Immature stages that feed on blood normally have a net increase in water content at the end of a blood-feeding cycle, but in adults the water content reverts to the pre-feeding level when the cycle is completed. Common themes are evident in diverse arthropods that feed on blood, particularly the physiological mechanisms used to respond to the sudden influx of water as well as the mechanisms used to counter water shortfalls that are encountered during the non-feeding, off-host state.
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Affiliation(s)
- Joshua B Benoit
- Department of Entomology, Ohio State University, Columbus, OH, United States.
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Schepel SA, Fox AJ, Miyauchi JT, Sou T, Yang JD, Lau K, Blum AW, Nicholson LK, Tiburcy F, Nachman RJ, Piermarini PM, Beyenbach KW. The single kinin receptor signals to separate and independent physiological pathways in Malpighian tubules of the yellow fever mosquito. Am J Physiol Regul Integr Comp Physiol 2010; 299:R612-22. [PMID: 20538895 DOI: 10.1152/ajpregu.00068.2010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the past, we have used the kinins of the cockroach Leucophaea (the leucokinins) to evaluate the mechanism of diuretic action of kinin peptides in Malpighian tubules of the yellow fever mosquito Aedes aegypti. Now using the kinins of Aedes (the aedeskinins), we have found that in isolated Aedes Malpighian tubules all three aedeskinins (1 microM) significantly 1) increased the rate of fluid secretion (V(S)), 2) hyperpolarized the basolateral membrane voltage (V(bl)), and 3) decreased the input resistance (R(in)) of principal cells, consistent with the known increase in the Cl(-) conductance of the paracellular pathway in Aedes Malpighian tubules. Aedeskinin-III, studied in further detail, significantly increased V(S) with an EC(50) of 1.5 x 10(-8) M. In parallel, the Na(+) concentration in secreted fluid significantly decreased, and the K(+) concentration significantly increased. The concentration of Cl(-) remained unchanged. While the three aedeskinins triggered effects on V(bl), R(in), and V(S), synthetic kinin analogs, which contain modifications of the COOH-terminal amide pentapeptide core sequence critical for biological activity, displayed variable effects. For example, kinin analog 1578 significantly stimulated V(S) but had no effect on V(bl) and R(in), whereas kinin analog 1708 had no effect on V(S) but significantly affected V(bl) and R(in). These observations suggest separate signaling pathways activated by kinins. One triggers the electrophysiological response, and the other triggers fluid secretion. It remains to be determined whether the two signaling pathways emanate from a single kinin receptor via agonist-directed signaling or from a differentially glycosylated receptor. Occasionally, Malpighian tubules did not exhibit a detectable response to natural and synthetic kinins. Hypothetically, the expression of the kinin receptor may depend on developmental, nutritional, and/or reproductive signals.
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Affiliation(s)
- Stephen A Schepel
- Dept. of Biomedical Sciences, VRT 8004, Cornell Univ., Ithaca, NY 14853, USA
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Boerjan B, Verleyen P, Huybrechts J, Schoofs L, De Loof A. In search for a common denominator for the diverse functions of arthropod corazonin: a role in the physiology of stress? Gen Comp Endocrinol 2010; 166:222-33. [PMID: 19748506 DOI: 10.1016/j.ygcen.2009.09.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Accepted: 09/04/2009] [Indexed: 02/01/2023]
Abstract
Corazonin (Crz) is an 11 amino acid C-terminally amidated neuropeptide that has been identified in most arthropods examined with the notable exception of beetles and an aphid. The Crz-receptor shares sequence similarity to the GnRH-AKH receptor family thus suggesting an ancestral function related to the control of reproduction and metabolism. In 1989, Crz was purified and identified as a potent cardioaccelerating agent in cockroaches (hence the Crz name based on "corazon", the Spanish word for "heart"). Since the initial assignment as a cardioacceleratory peptide, additional functions have been discovered, ranging from pigment migration in the integument of crustaceans and in the eye of locusts, melanization of the locust cuticle, ecdysis initiation and in various aspects of gregarization in locusts. The high degree of structural conservation of Crz, its well-conserved (immuno)-localization, mainly in specific neurosecretory cells in the pars lateralis, and its many functions, suggest that Crz is vital. Yet, Crz-deficient insects develop normally. Upon reexamining all known effects of Crz, a hypothesis was developed that the evolutionary ancient function of Crz may have been "to prepare animals for coping with the environmental stressors of the day". This function would then complement the role of pigment-dispersing factor (PDF), the prime hormonal effector of the clock, which is thought "to set a coping mechanism for the night".
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Affiliation(s)
- Bart Boerjan
- Functional Genomics and Proteomics, Department of Biology, K.U. Leuven, Naamsestraat 59, B-3000 Leuven, Belgium.
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Taneja-Bageshwar S, Strey A, Isaac RE, Coast GM, Zubrzak P, Pietrantonio PV, Nachman RJ. Biostable agonists that match or exceed activity of native insect kinins on recombinant arthropod GPCRs. Gen Comp Endocrinol 2009; 162:122-8. [PMID: 18983996 DOI: 10.1016/j.ygcen.2008.10.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 09/25/2008] [Accepted: 10/06/2008] [Indexed: 10/21/2022]
Abstract
The multifunctional arthropod 'insect kinins' share the evolutionarily conserved C-terminal pentapeptide motif Phe-X(1)-X(2)-Trp-Gly-NH(2), where X(1)=His, Asn, Ser, or Tyr and X(2)=Ser, Pro, or Ala. Insect kinins regulate diuresis in many species of insects. Compounds with similar biological activity could be exploited for the control of arthropod pest populations such as the mosquito Aedes aegypti (L.) and the southern cattle tick Rhipicephalus (Boophilus) microplus (Canestrini), vectors of human and animal pathogens, respectively. Insect kinins, however, are susceptible to fast enzymatic degradation by endogenous peptidases that severely limit their use as tools for pest control or for endocrinological studies. To enhance resistance to peptidases, analogs of the insect kinins incorporating bulky alpha,alpha-disubstituted amino acids in positions adjacent to both primary and secondary peptidase hydrolysis sites were synthesized. In comparison with a control insect kinin, several of these analogs are highly stable to hydrolysis by degradative enzymes ANCE, neprilysin and Leucine aminopeptidase. Six analogs were evaluated by calcium bioluminescence assay on recombinant receptors from mosquito and tick. Four of these analogs either matched or exceeded the potency of the control kinin peptide agonist. One of these was about 5-fold more potent than the control agonist on the tick receptor. This analog was 8-fold more potent than the control agonist on the mosquito receptor, and twice more potent than the endogenous Aedes kinin-II. The analog also demonstrated potent activity in an in vitro Aedes Malpighian tubule fluid secretion assay. Similar comparisons of analog potency cannot be made to tick kinins because no endogenous kinin has yet been identified. These potent, biostable analogs represent ideal new tools for endocrinologists studying arthropod kinin-regulated processes in vivo, particularly for ticks in which their role remains to be established.
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Audsley N, Weaver RJ. Neuropeptides associated with the regulation of feeding in insects. Gen Comp Endocrinol 2009; 162:93-104. [PMID: 18775723 DOI: 10.1016/j.ygcen.2008.08.003] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 07/01/2008] [Accepted: 08/03/2008] [Indexed: 11/18/2022]
Abstract
The stomatogastric nervous system plays a pivotal role in feeding behaviour. Central to this system is the frontal ganglion, which is responsible for foregut motor activity, and hence the passage of food through the gut. Many insect peptides, which exhibit myoactivity on the visceral muscles of the gut in vitro, have been detected in the stomatogastric nervous system by immunochemical or mass spectrometric techniques. This localisation of myoactive peptides, particularly in the frontal ganglion, implies roles for these peptides in the neural control and modulation of feeding in insects. Insect sulfakinins, tachykinins, allatotropin and proctolin have all been shown to stimulate the foregut muscles, whereas myosuppressins, myoinhibitory peptides and allatostatins all inhibited spontaneous contractions of the foregut in a variety of insects. Some of these peptides, when injected, inhibited feeding in vivo. Both the A-type and B-type allatostatins suppressed feeding activity when injected into the cockroach, Blattella germanica and the Manduca sexta C-type allatostatin and allatotropin inhibited feeding when injected into the larvae of two noctuid moths, Lacanobia oleracea and Spodoptera frugiperda, respectively. Injection of sulfakinins into the fly Phormia regina, the locust Schistocera gregaria and the cockroach B. germanica also suppressed feeding, whereas silencing the sulfakinin gene through the injection of double stranded RNA resulted in an increase in food consumption in the cricket Gryllus bimaculatus. The regulation of feeding in insects is clearly very complex, and involves the interaction of a number of mechanisms, one of which is the release, either centrally or locally, of neuropeptides. However, the role of neuropeptides, their mechanisms of action, interactions with each other, and their release are still poorly understood. It is also unclear why insects possess such a number of different peptides, some with multiples copies or homologues, which stimulate or inhibit gut motility, and how their release, sometimes from the same neurone, is regulated. These neuropeptides may also act at sites other than visceral muscles, such as centrally through the brain or on gut stretch receptors.
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Affiliation(s)
- N Audsley
- Environmental Biology Group, Central Science Laboratory, Sand Hutton, York YO41 1LZ, UK.
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Dircksen H. Insect ion transport peptides are derived from alternatively spliced genes and differentially expressed in the central and peripheral nervous system. ACTA ACUST UNITED AC 2009; 212:401-12. [PMID: 19151215 DOI: 10.1242/jeb.026112] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Insect ionic and fluid homeostasis relies upon the Malpighian tubules (MT) and different hindgut compartments. Primary urine formed in MTs is finally modified by ion, solute and water reabsorptive processes primarily in the hindgut under the control of several large peptide hormones. One of these, the ion transport peptide (ITP), is a chloride transport-stimulating and acid secretion-inhibiting hormone similar to crustacean hyperglycaemic hormones (CHHs). In locusts, moths and fruit flies, ITP together with the slightly longer ITPL isoforms, inactive in hindgut bioassays, arise by alternative splicing from very similar itp genes. ITP and ITPL are differentially distributed in (1) pars lateralis/retrocerebral complex neurosecretory cells (NSCs) containing both splice forms, (2) interneurons with either one of the splice forms, (3) hindgut-innervating abdominal ITP neurons (in Drosophila only), and (4) intrinsic, putative sensory NSCs in peripheral neurohaemal perisympathetic/perivisceral organs or transverse nerves (usually containing ITPL). Both splice forms occur as hormones released into the haemolymph in response to feeding or stress stimuli. ITPL mainly released from the peripheral NSCs is discussed as a competitive inhibitor (as established in vitro) of ITP action on yet to be identified hindgut ITP receptors. Furthermore, some evidence has been provided for possible ecdysis-related functions of ITP and/or ITPL in moths. The comparative data on the highly similar gene, precursor and primary structures and similar differential distributions in insect and crustacean NSCs suggest that CHH/ITP and ITPL neuropeptide-producing cells and their gene products share common phylogenetic ancestry.
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Affiliation(s)
- Heinrich Dircksen
- Department of Zoology, Stockholm University, Svante Arrhenius väg 14, 10691 Stockholm, Sweden.
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Coast GM. Neuroendocrine control of ionic homeostasis in blood-sucking insects. ACTA ACUST UNITED AC 2009; 212:378-86. [PMID: 19151213 DOI: 10.1242/jeb.024109] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The pioneering work of Simon Maddrell established that the rapid postprandial diuresis of the haematophagous insect Rhodnius prolixus is controlled by a diuretic hormone and demonstrated the role of the Malpighian tubules in meeting the volumic, osmotic and ionic challenges posed by an enormous blood meal. A number of diuretic and antidiuretic hormones that control secretion of primary urine by Malpighian tubules have now been identified, but little is known of the interplay between these hormones and those that regulate transport processes in the hindgut. This review therefore focuses on the control of ionic homeostasis in Rhodnius and mosquitoes, because primary urine is voided virtually unchanged during the rapid diuresis that follows a blood meal. At such times, the hindgut has a negligible impact on the volume and composition of the final urine, and neurohormones acting on the Malpighian tubules have a dominant role in the control of ionic homeostasis.
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Affiliation(s)
- Geoffrey M Coast
- Birkbeck College, School of Biological and Chemical Sciences, London, WC1E 7HX UK.
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