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Evans PD. Rapid signalling responses via the G protein-coupled estrogen receptor, GPER, in a hippocampal cell line. Steroids 2019; 152:108487. [PMID: 31499073 DOI: 10.1016/j.steroids.2019.108487] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 08/19/2019] [Accepted: 09/03/2019] [Indexed: 01/14/2023]
Abstract
The rapid non-genomic actions of 17β-estradiol in multiple tissues, including the nervous system, may involve the activation of the G-protein-coupled receptor, GPER. Different signalling pathways have been suggested to be activated by GPER in different cell lines and tissues. Controversially, GPER has also been suggested to be activated by the mineralocorticoid aldosterone, and by the non-steroidal diphenylacrylamide compound, STX, in some preparations. Evidence for the ability of the GPER agonist, G-1, and for aldosterone in the presence of the mineralocorticoid receptor antagonist, eplerenone, to potentiate forskolin-stimulated cyclic AMP levels in the hippocampal clonal cell line, mHippoE-18 is reviewed. The effects of both agents are blocked by the GPER antagonist G36, by PTX, (suggesting the involvement of Gi/o G proteins), by BAPTA-AM, (suggesting they are calcium sensitive), by wortmannin (suggesting an involvement of PI3Kinase) and by soluble amyloid-β peptides. STX also stimulates cyclic AMP levels in mHippoE-18 cells and these effects are blocked by G36 and PTX, as well as by amyloid-β peptides. This suggests that both aldosterone and STX may be capable of activating GPER in mHippoE-18 cells. Possible molecular mechanisms that may underlie these effects are discussed, together with possible forward directions for research on rapid non-genomic signalling by GPER, emphasising the importance of understanding the spatio-temporal aspects of its signalling in various tissues.
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Affiliation(s)
- Peter D Evans
- The Signalling Laboratory, The Babraham Institute, The Babraham Research Campus, Cambridge CB22 3AT, UK.
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2
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Evans PD. Aldosterone, STX and amyloid-β 1-42 peptides modulate GPER (GPR30) signalling in an embryonic mouse hippocampal cell line (mHippoE-18). Mol Cell Endocrinol 2019; 496:110537. [PMID: 31404576 DOI: 10.1016/j.mce.2019.110537] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/05/2019] [Accepted: 08/08/2019] [Indexed: 01/02/2023]
Abstract
The GPCR, GPER, mediates many of the rapid, non-genomic actions of 17β-estradiol in multiple tissues, including the nervous system. Controversially, it has also been suggested to be activated by aldosterone, and by the non-steroidal diphenylacrylamide compound, STX, in some preparations. Here, the ability of the GPER agonist, G-1, and aldosterone in the presence of the mineralocorticoid receptor antagonist, eplerenone, to potentiate forskolin-stimulated cyclic AMP levels in the hippocampal clonal cell line, mHippoE-18, are compared. Both stimulatory effects are blocked by the GPER antagonist G36, by PTX, (suggesting the involvement of Gi/o G proteins), by BAPTA-AM, (suggesting they are calcium sensitive), by wortmannin (suggesting an involvement of PI3Kinase) and by soluble amyloid-β peptides. STX also stimulates cyclic AMP levels in mHippoE-18 cells and these effects are blocked by G36 and PTX, as well as by amyloid-β peptides. This suggests that both aldosterone and STX may modulate GPER signalling in mHippoE-18 cells.
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Affiliation(s)
- Peter D Evans
- The Signalling Laboratory, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, UK.
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3
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Aranda GP, Hinojos SJ, Sabandal PR, Evans PD, Han KA. Behavioral Sensitization to the Disinhibition Effect of Ethanol Requires the Dopamine/Ecdysone Receptor in Drosophila. Front Syst Neurosci 2017; 11:56. [PMID: 28824387 PMCID: PMC5539124 DOI: 10.3389/fnsys.2017.00056] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 07/17/2017] [Indexed: 12/15/2022] Open
Abstract
Male flies under the influence of ethanol display disinhibited courtship, which is augmented with repeated ethanol exposures. We have previously shown that dopamine is important for this type of ethanol-induced behavioral sensitization but the underlying mechanism is unknown. Here we report that DopEcR, an insect G-protein coupled receptor that binds to dopamine and steroid hormone ecdysone, is a major receptor mediating courtship sensitization. Upon daily ethanol administration, dumb and damb mutant males defective in D1 (dDA1/DopR1) and D5 (DAMB/DopR2) dopamine receptors, respectively, showed normal courtship sensitization; however, the DopEcR-deficient der males exhibited greatly diminished sensitization. der mutant males nevertheless developed normal tolerance to the sedative effect of ethanol, indicating a selective function of DopEcR in chronic ethanol-associated behavioral plasticity. DopEcR plays a physiological role in behavioral sensitization since courtship sensitization in der males was reinstated when DopEcR expression was induced during adulthood but not during development. When examined for the DopEcR’s functional site, the der mutant’s sensitization phenotype was fully rescued by restored DopEcR expression in the mushroom body (MB) αβ and γ neurons. Consistently, we observed DopEcR immunoreactivity in the MB calyx and lobes in the wild-type Canton-S brain, which was barely detectable in the der brain. Behavioral sensitization to the locomotor-stimulant effect has been serving as a model for ethanol abuse and addiction. This is the first report elucidating the mechanism underlying behavioral sensitization to another stimulant effect of ethanol.
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Affiliation(s)
- Gissel P Aranda
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| | - Samantha J Hinojos
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| | - Paul R Sabandal
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| | - Peter D Evans
- The Inositide Laboratory, The Babraham InstituteCambridge, United Kingdom
| | - Kyung-An Han
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
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Evans PD, Mueller KL, Gamazon ER, Cox NJ, Tomblin JB. A genome-wide sib-pair scan for quantitative language traits reveals linkage to chromosomes 10 and 13. Genes Brain Behav 2016; 14:387-97. [PMID: 25997078 DOI: 10.1111/gbb.12223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 05/06/2015] [Accepted: 05/06/2015] [Indexed: 02/03/2023]
Abstract
Although there is considerable evidence that individual differences in language development are highly heritable, there have been few genome-wide scans to locate genes associated with the trait. Previous analyses of language impairment have yielded replicable evidence for linkage to regions on chromosomes 16q, 19q, 13q (within lab) and at 13q (between labs). Here we report the first linkage study to screen the continuum of language ability, from normal to disordered, as found in the general population. 383 children from 147 sib-ships (214 sib-pairs) were genotyped on the Illumina(®) Linkage IVb Marker Panel using three composite language-related phenotypes and a measure of phonological memory (PM). Two regions (10q23.33; 13q33.3) yielded genome-wide significant peaks for linkage with PM. A peak suggestive of linkage was also found at 17q12 for the overall language composite. This study presents two novel genetic loci for the study of language development and disorders, but fails to replicate findings by previous groups. Possible reasons for this are discussed.
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Affiliation(s)
- P D Evans
- Department of Medicine, The University of Chicago, IL, USA
| | - K L Mueller
- Murdoch Childrens Research Institute, Melbourne, Australia.,Department of Communication Sciences and Disorders, The University of Iowa, IA, USA
| | - E R Gamazon
- Department of Medicine, The University of Chicago, IL, USA.,Present address: Division of Genetic Medicine, Department of Medicine, Vanderbilt University, Nashville, TN, USA
| | - N J Cox
- Department of Medicine, The University of Chicago, IL, USA.,Department of Communication Sciences and Disorders, The University of Iowa, IA, USA.,Present address: Division of Genetic Medicine, Department of Medicine, Vanderbilt University, Nashville, TN, USA
| | - J B Tomblin
- Department of Communication Sciences and Disorders, The University of Iowa, IA, USA
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5
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Evans NJ, Bayliss AL, Reale V, Evans PD. Characterisation of Signalling by the Endogenous GPER1 (GPR30) Receptor in an Embryonic Mouse Hippocampal Cell Line (mHippoE-18). PLoS One 2016; 11:e0152138. [PMID: 26998610 PMCID: PMC4801207 DOI: 10.1371/journal.pone.0152138] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 03/09/2016] [Indexed: 01/14/2023] Open
Abstract
Estrogen can modulate neuronal development and signalling by both genomic and non-genomic pathways. Many of its rapid, non-genomic effects on nervous tissue have been suggested to be mediated via the activation of the estrogen sensitive G-protein coupled receptor (GPER1 or GPR30). There has been much controversy over the cellular location, signalling properties and endogenous activators of GPER1. Here we describe the pharmacology and signalling properties of GPER1 in an immortalized embryonic hippocampal cell line, mHippoE-18. This cell line does not suffer from the inherent problems associated with the study of this receptor in native tissue or the problems associated with heterologously expression in clonal cell lines. In mHippoE-18 cells, 17β-Estradiol can mediate a dose-dependent rapid potentiation of forskolin-stimulated cyclic AMP levels but does not appear to activate the ERK1/2 pathway. The effect of 17β-Estradiol can be mimicked by the GPER1 agonist, G1, and also by tamoxifen and ICI 182,780 which activate GPER1 in a variety of other preparations. The response is not mimicked by the application of the classical estrogen receptor agonists, PPT, (an ERα agonist) or DPN, (an ERβ agonist), further suggesting that this effect of 17β-Estradiol is mediated through the activation of GPER1. However, after exposure of the cells to the GPER1 specific antagonists, G15 and G36, the stimulatory effects of the above agonists are replaced by dose-dependent inhibitions of forskolin-stimulated cyclic AMP levels. This inhibitory effect is mimicked by aldosterone in a dose-dependent way even in the absence of the GPER1 antagonists. The results are discussed in terms of possible "Biased Antagonism" whereby the antagonists change the conformation of the receptor resulting in changes in the agonist induced coupling of the receptor to different second messenger pathways.
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Affiliation(s)
- Nicholas J. Evans
- The Signalling Laboratory, The Babraham Institute, Cambridge, CB22 3AT, United Kingdom
| | - Asha L. Bayliss
- The Signalling Laboratory, The Babraham Institute, Cambridge, CB22 3AT, United Kingdom
| | - Vincenzina Reale
- The Signalling Laboratory, The Babraham Institute, Cambridge, CB22 3AT, United Kingdom
| | - Peter D. Evans
- The Signalling Laboratory, The Babraham Institute, Cambridge, CB22 3AT, United Kingdom
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6
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Chipman AD, Ferrier DEK, Brena C, Qu J, Hughes DST, Schröder R, Torres-Oliva M, Znassi N, Jiang H, Almeida FC, Alonso CR, Apostolou Z, Aqrawi P, Arthur W, Barna JCJ, Blankenburg KP, Brites D, Capella-Gutiérrez S, Coyle M, Dearden PK, Du Pasquier L, Duncan EJ, Ebert D, Eibner C, Erikson G, Evans PD, Extavour CG, Francisco L, Gabaldón T, Gillis WJ, Goodwin-Horn EA, Green JE, Griffiths-Jones S, Grimmelikhuijzen CJP, Gubbala S, Guigó R, Han Y, Hauser F, Havlak P, Hayden L, Helbing S, Holder M, Hui JHL, Hunn JP, Hunnekuhl VS, Jackson L, Javaid M, Jhangiani SN, Jiggins FM, Jones TE, Kaiser TS, Kalra D, Kenny NJ, Korchina V, Kovar CL, Kraus FB, Lapraz F, Lee SL, Lv J, Mandapat C, Manning G, Mariotti M, Mata R, Mathew T, Neumann T, Newsham I, Ngo DN, Ninova M, Okwuonu G, Ongeri F, Palmer WJ, Patil S, Patraquim P, Pham C, Pu LL, Putman NH, Rabouille C, Ramos OM, Rhodes AC, Robertson HE, Robertson HM, Ronshaugen M, Rozas J, Saada N, Sánchez-Gracia A, Scherer SE, Schurko AM, Siggens KW, Simmons D, Stief A, Stolle E, Telford MJ, Tessmar-Raible K, Thornton R, van der Zee M, von Haeseler A, Williams JM, Willis JH, Wu Y, Zou X, Lawson D, Muzny DM, Worley KC, Gibbs RA, Akam M, Richards S. The first myriapod genome sequence reveals conservative arthropod gene content and genome organisation in the centipede Strigamia maritima. PLoS Biol 2014; 12:e1002005. [PMID: 25423365 PMCID: PMC4244043 DOI: 10.1371/journal.pbio.1002005] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 10/15/2014] [Indexed: 12/14/2022] Open
Abstract
Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific life history. Arthropods are the most abundant animals on earth. Among them, insects clearly dominate on land, whereas crustaceans hold the title for the most diverse invertebrates in the oceans. Much is known about the biology of these groups, not least because of genomic studies of the fruit fly Drosophila, the water flea Daphnia, and other species used in research. Here we report the first genome sequence from a species belonging to a lineage that has previously received very little attention—the myriapods. Myriapods were among the first arthropods to invade the land over 400 million years ago, and survive today as the herbivorous millipedes and venomous centipedes, one of which—Strigamia maritima—we have sequenced here. We find that the genome of this centipede retains more characteristics of the presumed arthropod ancestor than other sequenced insect genomes. The genome provides access to many aspects of myriapod biology that have not been studied before, suggesting, for example, that they have diversified receptors for smell that are quite different from those used by insects. In addition, it shows specific consequences of the largely subterranean life of this particular species, which seems to have lost the genes for all known light-sensing molecules, even though it still avoids light.
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Affiliation(s)
- Ariel D. Chipman
- The Department of Ecology, Evolution and Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - David E. K. Ferrier
- The Scottish Oceans Institute, Gatty Marine Laboratory, University of St Andrews, St Andrews, Fife, United Kingdom
| | - Carlo Brena
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Jiaxin Qu
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Daniel S. T. Hughes
- EMBL - European Bioinformatics Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Reinhard Schröder
- Institut für Biowissenschaften, Universität Rostock, Abt. Genetik, Rostock, Germany
| | | | - Nadia Znassi
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Huaiyang Jiang
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Francisca C. Almeida
- Departament de Genètica and Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Universidad Nacional de Tucumán, Facultad de Ciencias Naturales e Instituto Miguel Lillo, San Miguel de Tucumán, Argentina
| | - Claudio R. Alonso
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Zivkos Apostolou
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- Institute of Molecular Biology & Biotechnology, Foundation for Research & Technology - Hellas, Heraklion, Crete, Greece
| | - Peshtewani Aqrawi
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Wallace Arthur
- Department of Zoology, National University of Ireland, Galway, Ireland
| | | | - Kerstin P. Blankenburg
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Daniela Brites
- Evolutionsbiologie, Zoologisches Institut, Universität Basel, Basel, Switzerland
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | - Marcus Coyle
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Peter K. Dearden
- Gravida and Genetics Otago, Biochemistry Department, University of Otago, Dunedin, New Zealand
| | - Louis Du Pasquier
- Evolutionsbiologie, Zoologisches Institut, Universität Basel, Basel, Switzerland
| | - Elizabeth J. Duncan
- Gravida and Genetics Otago, Biochemistry Department, University of Otago, Dunedin, New Zealand
| | - Dieter Ebert
- Evolutionsbiologie, Zoologisches Institut, Universität Basel, Basel, Switzerland
| | - Cornelius Eibner
- Department of Zoology, National University of Ireland, Galway, Ireland
| | - Galina Erikson
- Razavi Newman Center for Bioinformatics, Salk Institute, La Jolla, California, United States of America
- Scripps Translational Science Institute, La Jolla, California, United States of America
| | | | - Cassandra G. Extavour
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Liezl Francisco
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Toni Gabaldón
- Centre for Genomic Regulation, Barcelona, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - William J. Gillis
- Department of Biochemistry and Cell Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, New York, United States of America
| | | | - Jack E. Green
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Sam Griffiths-Jones
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | | | - Sai Gubbala
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Roderic Guigó
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Center for Genomic Regulation, Barcelona, Spain
| | - Yi Han
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Frank Hauser
- Center for Functional and Comparative Insect Genomics, University of Copenhagen, Copenhagen, Denmark
| | - Paul Havlak
- Department of Ecology and Evolutionary Biology, Rice University, Houston, Texas, United States of America
| | - Luke Hayden
- Department of Zoology, National University of Ireland, Galway, Ireland
| | - Sophie Helbing
- Institut für Biologie, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Michael Holder
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jerome H. L. Hui
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Julia P. Hunn
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Vera S. Hunnekuhl
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - LaRonda Jackson
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Mehwish Javaid
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Shalini N. Jhangiani
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Francis M. Jiggins
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Tamsin E. Jones
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Tobias S. Kaiser
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Divya Kalra
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Nathan J. Kenny
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Viktoriya Korchina
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Christie L. Kovar
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - F. Bernhard Kraus
- Institut für Biologie, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
- Department of Laboratory Medicine, University Hospital Halle (Saale), Halle (Saale), Germany
| | - François Lapraz
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Sandra L. Lee
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jie Lv
- Department of Ecology and Evolutionary Biology, Rice University, Houston, Texas, United States of America
| | - Christigale Mandapat
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Gerard Manning
- Razavi Newman Center for Bioinformatics, Salk Institute, La Jolla, California, United States of America
| | - Marco Mariotti
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Center for Genomic Regulation, Barcelona, Spain
| | - Robert Mata
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Tittu Mathew
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Tobias Neumann
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
- Center for Integrative Bioinformatics Vienna, Max F. Perutz Laboratories, University of Vienna, Medical University of Vienna, Vienna, Austria
| | - Irene Newsham
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Dinh N. Ngo
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Maria Ninova
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Geoffrey Okwuonu
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Fiona Ongeri
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - William J. Palmer
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Shobha Patil
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Pedro Patraquim
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Christopher Pham
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Ling-Ling Pu
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Nicholas H. Putman
- Department of Ecology and Evolutionary Biology, Rice University, Houston, Texas, United States of America
| | - Catherine Rabouille
- Hubrecht Institute for Developmental Biology and Stem Cell Research, Utrecht, The Netherlands
| | - Olivia Mendivil Ramos
- The Scottish Oceans Institute, Gatty Marine Laboratory, University of St Andrews, St Andrews, Fife, United Kingdom
| | - Adelaide C. Rhodes
- Harte Research Institute, Texas A&M University Corpus Christi, Corpus Christi, Texas, United States of America
| | - Helen E. Robertson
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Hugh M. Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Matthew Ronshaugen
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Julio Rozas
- Departament de Genètica and Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain
| | - Nehad Saada
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Alejandro Sánchez-Gracia
- Departament de Genètica and Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain
| | - Steven E. Scherer
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Andrew M. Schurko
- Department of Biology, Hendrix College, Conway, Arkansas, United States of America
| | - Kenneth W. Siggens
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - DeNard Simmons
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Anna Stief
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- Institute for Biochemistry and Biology, University Potsdam, Potsdam-Golm, Germany
| | - Eckart Stolle
- Institut für Biologie, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Maximilian J. Telford
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Kristin Tessmar-Raible
- Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
- Research Platform “Marine Rhythms of Life”, Vienna, Austria
| | - Rebecca Thornton
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | | | - Arndt von Haeseler
- Center for Integrative Bioinformatics Vienna, Max F. Perutz Laboratories, University of Vienna, Medical University of Vienna, Vienna, Austria
- Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Vienna, Austria
| | - James M. Williams
- Department of Biology, Hendrix College, Conway, Arkansas, United States of America
| | - Judith H. Willis
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Yuanqing Wu
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Xiaoyan Zou
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Daniel Lawson
- EMBL - European Bioinformatics Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Donna M. Muzny
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Kim C. Worley
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Richard A. Gibbs
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Michael Akam
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Stephen Richards
- Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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7
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Evans PD, Bayliss A, Reale V. GPCR-mediated rapid, non-genomic actions of steroids: comparisons between DmDopEcR and GPER1 (GPR30). Gen Comp Endocrinol 2014; 195:157-63. [PMID: 24188886 DOI: 10.1016/j.ygcen.2013.10.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 10/16/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
Abstract
Steroid hormones classically mediate their actions by binding to intracellular receptor proteins that migrate to the nucleus and act as transcription factors to change gene expression. However, evidence is now accumulating for rapid, non-genomic effects of steroids. There is considerable controversy over the mechanisms underlying such effects. In a number of cases evidence has been presented for the direct activation of G-protein coupled receptors (GPCRs) by steroids, either at the plasma membrane, or at intracellular locations. Here, we will focus on the non-genomic actions of ecdysteroids on a Drosophila GPCR, DopEcR (CG18314), which can be activated by both ecdysone and the catecholamine, dopamine. We will also point out parallels between this system and the activation of the vertebrate GPCR, GPER1 (GPR30), which is thought to be activated by 17β-estradiol. We propose that the cellular localization and signalling properties of both DopEcR and GPER1 may be cell specific and depend upon their interactions with both accessory molecules and signalling pathways.
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Affiliation(s)
- Peter D Evans
- The Inositide Laboratory, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK.
| | - Asha Bayliss
- The Inositide Laboratory, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK.
| | - Vincenzina Reale
- The Inositide Laboratory, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK.
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8
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Bayliss AL, Evans PD. Characterisation of AmphiAmR11, an amphioxus (Branchiostoma floridae) D2-dopamine-like G protein-coupled receptor. PLoS One 2013; 8:e80833. [PMID: 24265838 PMCID: PMC3827198 DOI: 10.1371/journal.pone.0080833] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 10/08/2013] [Indexed: 11/20/2022] Open
Abstract
The evolution of the biogenic amine signalling system in vertebrates is unclear. However, insights can be obtained from studying the structures and signalling properties of biogenic amine receptors from the protochordate, amphioxus, which is an invertebrate species that exists at the base of the chordate lineage. Here we describe the signalling properties of AmphiAmR11, an amphioxus (Branchiostoma floridae) G protein-coupled receptor which has structural similarities to vertebrate α2-adrenergic receptors but which functionally acts as a D2 dopamine-like receptor when expressed in Chinese hamster ovary -K1 cells. AmphiAmR11 inhibits forskolin-stimulated cyclic AMP levels with tyramine, phenylethylamine and dopamine being the most potent agonists. AmphiAmR11 also increases mitogen-activated protein kinase activity and calcium mobilisation, and in both pathways, dopamine was found to be more potent than tyramine. Thus, differences in the relative effectiveness of various agonists in the different second messenger assay systems suggest that the receptor displays agonist-specific coupling (biased agonism) whereby different agonists stabilize different conformations of the receptor which lead to the enhancement of one signalling pathway over another. The present study provides insights into the evolution of α2-adrenergic receptor signalling and support the hypothesis that α2-adrenergic receptors evolved from D2-dopamine receptors. The AmphiAmR11 receptor may represent a transition state between D2-dopamine receptors and α2-adrenergic receptors.
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MESH Headings
- Adenylyl Cyclases/metabolism
- Animals
- CHO Cells
- Calcium/metabolism
- Calcium Signaling/drug effects
- Cricetulus
- Cyclic AMP/metabolism
- Dopamine D2 Receptor Antagonists
- Lancelets/genetics
- Lancelets/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Pertussis Toxin/pharmacology
- Receptors, Biogenic Amine/agonists
- Receptors, Biogenic Amine/antagonists & inhibitors
- Receptors, Biogenic Amine/genetics
- Receptors, Biogenic Amine/metabolism
- Receptors, Dopamine D2/agonists
- Receptors, Dopamine D2/genetics
- Receptors, Dopamine D2/metabolism
- Receptors, G-Protein-Coupled/agonists
- Receptors, G-Protein-Coupled/antagonists & inhibitors
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
- Asha L. Bayliss
- The Signalling Laboratory, the Babraham Institute, Cambridge, United Kingdom
| | - Peter D. Evans
- The Signalling Laboratory, the Babraham Institute, Cambridge, United Kingdom
- * E-mail:
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9
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Srivastava DP, Evans PD. G-protein oestrogen receptor 1: trials and tribulations of a membrane oestrogen receptor. J Neuroendocrinol 2013; 25:1219-30. [PMID: 23822769 DOI: 10.1111/jne.12071] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/20/2013] [Accepted: 06/29/2013] [Indexed: 11/29/2022]
Abstract
Oestrogens are now recognised to be able to initiate rapid, fast responses, in addition to their classical, longer-term actions. There is a growing appreciation of the potential implications of this mode of action for oestrogenic signalling in both neuronal and non-neuronal systems. As such, much effort has been made to determine the mechanisms that are critical for transducing these rapid effects into cellular responses. Recently, an orphan G-protein-coupled receptor (GPCR), termed GPR30, was identified as an oestrogen-sensitive receptor in cancer cells. This receptor, now term G-protein oestrogen receptor 1 (GPER1) has been the subject of many investigations, and a role for this receptor in the nervous system is now emerging. In this review, we highlight some of the more recent advances in our understanding of the distribution and subcellular localisation of this receptor in the brain, as well as some of the evidence for the potential role that this receptor may play in the brain. We then discuss some of the controversies surrounding the pharmacology of this receptor, and attempt to reconcile these by suggesting that the 'agonist-specific coupling' model of GPCR function may provide a potential explanation for some of the divergent reports of GPER1 pharmacology.
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Affiliation(s)
- D P Srivastava
- Department of Neuroscience & Centre for the Cellular Basis of Behaviour, The James Black Centre, Institute of Psychiatry, King's College London, London, UK
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10
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Bayliss A, Roselli G, Evans PD. A comparison of the signalling properties of two tyramine receptors from Drosophila. J Neurochem 2013; 125:37-48. [PMID: 23356740 DOI: 10.1111/jnc.12158] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 01/04/2013] [Accepted: 01/14/2013] [Indexed: 12/01/2022]
Abstract
In invertebrates, the phenolamines, tyramine and octopamine, mediate many functional roles usually associated with the catecholamines, noradrenaline and adrenaline, in vertebrates. The α- and β-adrenergic classes of insect octopamine receptor are better activated by octopamine than tyramine. Similarly, the Tyramine 1 subgroup of receptors (or Octopamine/Tyramine receptors) are better activated by tyramine than octopamine. However, recently, a new Tyramine 2 subgroup of receptors was identified, which appears to be activated highly preferentially by tyramine. We examined immunocytochemically the ability of CG7431, the founding member of this subgroup from Drosophila melanogaster, to be internalized in transfected Chinese hamster ovary (CHO) cells by different agonists. It was only internalized after activation by tyramine. Conversely, the structurally related receptor, CG16766, was internalized by a number of biogenic amines, including octopamine, dopamine, noradrenaline, adrenaline, which also were able to elevate cyclic AMP levels. Studies with synthetic agonists and antagonists confirm that CG16766 has a different pharmacological profile to that of CG7431. Species orthologues of CG16766 were only found in Drosophila species, whereas orthologues of CG7431 could be identified in the genomes of a number of insect species. We propose that CG16766 represents a new group of tyramine receptors, which we have designated the Tyramine 3 receptors.
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Affiliation(s)
- Asha Bayliss
- The Inositide Laboratory, The Babraham Institute, Cambridge, UK
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11
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Srivastava DP, Woolfrey KM, Evans PD. Mechanisms underlying the interactions between rapid estrogenic and BDNF control of synaptic connectivity. Neuroscience 2012; 239:17-33. [PMID: 23246844 DOI: 10.1016/j.neuroscience.2012.12.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 12/03/2012] [Accepted: 12/04/2012] [Indexed: 12/14/2022]
Abstract
The effects of the steroid hormone 17β-estradiol and the neurotrophin brain-derived neurotrophic factor (BDNF) on neuronal physiology have been well investigated. Numerous studies have demonstrated that each signal can exert powerful influences on the structure and function of synapses, and specifically on dendritic spines, both within short and long time frames. Moreover, it has been suggested that BDNF is required for the long-term, or genomic, actions of 17β-estradiol on dendritic spines, via its ability to regulate the expression of neurotrophins. Here we focus on the acute, or rapid effects, of 17β-estradiol and BDNF, and their ability to activate specific signalling cascades, resulting in alterations in dendritic spine morphology. We first review recent literature describing the mechanisms by which 17β-estradiol activates these pathways, and the resulting alterations in dendritic spine number. We then describe the molecular mechanisms underlying acute modulation of dendritic spine morphology by BDNF. Finally, we consider how this new evidence may suggest that the temporal interactions of 17β-estradiol and BDNF can occur more rapidly than previously reported. Building on these new data, we propose a novel model for the interactions of this steroid and neurotrophin, whereby rapid, non-genomic 17β-estradiol and acute BDNF signal in a co-operative manner, resulting in dendritic spine formation and subsequent stabilization in support of synapse and circuit plasticity. This extended hypothesis suggests an additional mechanism by which these two signals may modulate dendritic spines in a time-specific manner.
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Affiliation(s)
- D P Srivastava
- Department of Neuroscience & Centre for the Cellular Basis of Behaviour, The James Black Centre, Institute of Psychiatry, King's College London, London SE5 9NU, UK.
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12
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Bayliss A, Evans PD. Characterisation of AmphiAmR4, an amphioxus (Branchiostoma floridae) α₂-adrenergic-like G-protein-coupled receptor. Invert Neurosci 2012. [PMID: 23183848 DOI: 10.1007/s10158-012-0145-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Little is known about the evolutionary relationship between vertebrate adrenergic receptors and invertebrate octopamine and tyramine receptors. The complexity of the adrenergic signalling system is believed to be an innovation of the vertebrate lineage but the presence of noradrenaline has been reported in some invertebrate species. The cephalochordate, amphioxus (Branchiostoma floridae), is an ideal model organism for studying the evolution of vertebrate GPCRs, given its unique position at the base of the chordate lineage. Here, we describe the pharmacological characterisation and second messenger coupling abilities of AmphiAmR4, which clusters with α₂-adrenergic receptors in a phylogenetic tree but also shares a high sequence similarity to invertebrate octopamine/tyramine receptors in both BLAST and Hidden Markov Model analyses. Thus, it was of particular interest to determine if AmphiAmR4 displayed similar functional properties to the vertebrate α₂-adrenergic receptors or to invertebrate octopamine or tyramine receptors. When stably expressed in Chinese hamster ovary (CHO) cells, noradrenaline couples the receptor to both the activation of adenylyl cyclase and to the activation of the MAPKinase pathway. Pharmacological studies with a wide range of agonists and antagonists suggest that AmphiAmR4 functions as an α₂-adrenergic-like receptor when expressed in CHO cells.
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Affiliation(s)
- Asha Bayliss
- The Inositide Laboratory, The Babraham Institute, The Babraham Research Campus, Cambridge CB22 3AT, UK
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13
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Abstract
Dopamine receptors function to control many aspects of motor control and other forms of behaviour in both vertebrates and invertebrates. They can be divided into two main groups (D(1) and D(2)) based on sequence similarity, ligand affinity and effector coupling. However, little is known about the pharmacology and functionality of dopamine receptors in the deuterostomian invertebrates, such as the cephalochordate amphioxus (Branchiostoma floridae) which has recently been placed as the most basal of all the chordates. A bioinformatic study shows that amphioxus has at least three dopamine D(1)-like receptor sequences. One of these receptors, AmphiD(1)/beta, was found to have high levels of sequence similarity to both vertebrate D(1) receptors and to beta-adrenergic receptors. Here, we report on the cloning of AmphiD(1)/beta from an adult amphioxus cDNA library, and its pharmacological characterization subsequent to its expression in both mammalian cell lines and Xenopus oocytes. It was found that AmphiD(1)/beta has a similar pharmacology to vertebrate D(1) receptors, including responding to benzodiazepine ligands. The pharmacology of the receptor exhibits 'agonist-specific coupling' depending upon the second messenger pathway to which it is linked. Moreover, no pharmacological characteristics were observed to suggest that AmphiD(1)/beta may be an amphioxus orthologue of vertebrate beta-adrenergic receptors.
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Affiliation(s)
- Chloe Burman
- The Inositide Laboratory, The Babraham Institute, Cambridge, UK
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14
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15
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Burman C, Maqueira B, Coadwell J, Evans PD. Eleven new putative aminergic G-protein coupled receptors from Amphioxus (Branchiostoma floridae): identification, sequence analysis and phylogenetic relationship. Invert Neurosci 2007; 7:87-98. [PMID: 17225134 DOI: 10.1007/s10158-006-0041-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Accepted: 12/19/2006] [Indexed: 11/29/2022]
Abstract
We have identified eleven novel aminergic-like G-protein coupled receptor (GPCRs) sequences (named AmphiAmR1-11) by searching the genomic trace sequence database for the amphioxus species, Branchiostoma floridae. They share many of the structural motifs that have been used to characterize vertebrate and invertebrate aminergic GPCRs. A preliminary classification of these receptors has been carried out using both BLAST and Hidden Markov Model analyses. The amphioxus genome appears to express a number of D1-like dopamine receptor sequences, including one related to insect dopamine receptors. It also expresses a number of receptors that resemble invertebrate octopamine/tyramine receptors and others that resemble vertebrate alpha-adrenergic receptors. Amphioxus also expresses receptors that resemble vertebrate histamine receptors. Several of the novel receptor sequences have been identified in amphioxus cDNA libraries from a number of tissues.
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Affiliation(s)
- Chloe Burman
- The Inositide Laboratory, The Babraham Institute, Cambridge, UK
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16
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Dossey AT, Reale V, Chatwin H, Zachariah C, deBono M, Evans PD, Edison AS. NMR analysis of Caenorhabditis elegans FLP-18 neuropeptides: implications for NPR-1 activation. Biochemistry 2006; 45:7586-97. [PMID: 16768454 PMCID: PMC2517133 DOI: 10.1021/bi0603928] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phe-Met-Arg-Phe-NH2 (FMRFamide)-like peptides (FLPs) are the largest neuropeptide family in animals, particularly invertebrates. FLPs are characterized by a C-N-terminal gradient of decreasing amino acid conservation. Neuropeptide receptor 1 (NPR-1) is a G-protein coupled receptor (GPCR), which has been shown to be a strong regulator of foraging behavior and aggregation responses in Caenorhabditis elegans. Recently, ligands for NPR-1 were identified as neuropeptides coded by the precursor genes flp-18 and flp-21 in C. elegans. The flp-18 gene encodes eight FLPs including DFDGAMPGVLRF-NH2 and EMPGVLRF-NH2. These peptides exhibit considerably different activities on NPR-1, with the longer one showing a lower potency. We have used nuclear magnetic resonance and biological activity to investigate structural features that may explain these activity differences. Our data demonstrate that long-range electrostatic interactions exist between N-terminal aspartates and the C-terminal penultimate arginine as well as N-terminal hydrogen-bonding interactions that form transient loops within DFDGAMPGVLRF-NH2. We hypothesize that these loops, along with peptide charge, diminish the activity of this peptide on NPR-1 relative to that of EMPGVLRF-NH2. These results provide some insight into the large amino acid diversity in FLPs.
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Affiliation(s)
- Aaron T Dossey
- McKnight Brain Institute, University of Florida, 100 South Newell Drive, Building 59, Room LG-150, Gainesville, Florida 32611, USA
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17
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Evans PD, Robb S, Cuthbert BA. Insect neuropeptides-identification, establishment of functional roles and novel target sites for pesticides. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/ps.2780250110] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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18
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Srivastava DP, Yu EJ, Kennedy K, Chatwin H, Reale V, Hamon M, Smith T, Evans PD. Rapid, nongenomic responses to ecdysteroids and catecholamines mediated by a novel Drosophila G-protein-coupled receptor. J Neurosci 2006; 25:6145-55. [PMID: 15987944 PMCID: PMC6725065 DOI: 10.1523/jneurosci.1005-05.2005] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Nongenomic response pathways mediate many of the rapid actions of steroid hormones, but the mechanisms underlying such responses remain controversial. In some cases, cell-surface expression of classical nuclear steroid receptors has been suggested to mediate these effects, but, in a few instances, specific G-protein-coupled receptors (GPCRs) have been reported to be responsible. Here, we describe the activation of a novel, neuronally expressed Drosophila GPCR by the insect ecdysteroids ecdysone (E) and 20-hydroxyecdysone (20E). This is the first report of an identified insect GPCR interacting with steroids. The Drosophila melanogaster dopamine/ecdysteroid receptor (DmDopEcR) shows sequence homology with vertebrate beta-adrenergic receptors and is activated by dopamine (DA) to increase cAMP levels and to activate the phosphoinositide 3-kinase pathway. Conversely, E and 20E show high affinity for the receptor in binding studies and can inhibit the effects of DA, as well as coupling the receptor to a rapid activation of the mitogen-activated protein kinase pathway. The receptor may thus represent the Drosophila homolog of the vertebrate "gamma-adrenergic receptors," which are responsible for the modulation of various activities in brain, blood vessels, and pancreas. Thus, DmDopEcR can function as a cell-surface GPCR that may be responsible for some of the rapid, nongenomic actions of ecdysteroids, during both development and signaling in the mature adult nervous system.
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Affiliation(s)
- Deepak P Srivastava
- The Inositide Laboratory, The Babraham Institute, Cambridge CB2 4AT, United Kingdom
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19
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Evans PD, Maqueira B. Insect octopamine receptors: a new classification scheme based on studies of cloned Drosophila G-protein coupled receptors. Invert Neurosci 2005; 5:111-8. [PMID: 16211376 DOI: 10.1007/s10158-005-0001-z] [Citation(s) in RCA: 187] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2005] [Accepted: 07/20/2005] [Indexed: 11/29/2022]
Abstract
Insect octopamine receptors are G-protein coupled receptors. They can be coupled to second messenger pathways to mediate either increases or decreases in intracellular cyclic AMP levels or the generation of intracellular calcium signals. Insect octopamine receptors were originally classified on the basis of second messenger changes induced in a variety of intact tissue preparations. Such a classification system is problematic if more than one receptor subtype is present in the same tissue preparation. Recent progress on the cloning and characterization in heterologous cell systems of octopamine receptors from Drosophila and other insects is reviewed. A new classification system for insect octopamine receptors into "alpha-adrenergic-like octopamine receptors (OctalphaRs)", "beta-adrenergic-like octopamine receptors (OctbetaRs)" and "octopamine/tyramine (or tyraminergic) receptors" is proposed based on their similarities in structure and in signalling properties with vertebrate adrenergic receptors. In future studies on the molecular basis of octopamine signalling in individual tissues it will be essential to identify the relative expression levels of the different classes of octopamine receptor present. In addition, it will be essential to identify if co-expression of such receptors in the same cells results in the formation of oligomeric receptors with specific emergent pharmacological and signalling properties.
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Affiliation(s)
- Peter D Evans
- The Inositide Laboratory, The Babraham Institute, Cambridge, CB2 4AT, UK.
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20
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Maqueira B, Chatwin H, Evans PD. Identification and characterization of a novel family of Drosophila beta-adrenergic-like octopamine G-protein coupled receptors. J Neurochem 2005; 94:547-60. [PMID: 15998303 DOI: 10.1111/j.1471-4159.2005.03251.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Insect octopamine receptors carry out many functional roles traditionally associated with vertebrate adrenergic receptors. These include control of carbohydrate metabolism, modulation of muscular tension, modulation of sensory inputs and modulation of memory and learning. The activation of octopamine receptors mediating many of these actions leads to increases in the levels of cyclic AMP. However, to date none of the insect octopamine receptors that have been cloned have been convincingly shown to be capable of directly mediating selective and significant increases in cyclic AMP levels. Here we report on the identification and characterization of a novel, neuronally expressed family of three Drosophila G-protein coupled receptors that are selectively coupled to increases in intracellular cyclic AMP levels by octopamine. This group of receptors, DmOct beta1R (CG6919), DmOct beta2R (CG6989) and DmOct beta3R (CG7078) shows homology to vertebrate beta-adrenergic receptors. When expressed in Chinese hamster ovary cells all three receptors show a strong preference for octopamine over tyramine for the accumulation of cyclic AMP but show unique pharmacological profiles when tested with a range of synthetic agonists and antagonists. Thus, the pharmacological profile of individual insect tissue responses to octopamine might vary with the combination and the degree of expression of the individual octopamine receptors present.
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21
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Abstract
A case of thoracic vertebral osteomyelitis due to Salmonella enteritidis phage type 2 in an immunocompetent patient is reported. The patient initially presented with abdominal, urinary and chest symptoms, which were followed by a large pleural effusion. The infection was successfully treated with ciprofloxacin. This is the only case of salmonella thoracic vertebral osteomyelitis in an immunocompetent patient reported in the English literature.
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Affiliation(s)
- S K Gupta
- Department of Orthopaedics, Medicine and Microbiology, Royal Glamorgan Hospital, Llantrisant, Pontyprid, UK
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22
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Reale V, Chatwin HM, Evans PD. The activation of G-protein gated inwardly rectifying K+ channels by a cloned Drosophila melanogaster neuropeptide F-like receptor. Eur J Neurosci 2004; 19:570-6. [PMID: 14984407 DOI: 10.1111/j.0953-816x.2003.03141.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A Drosophila melanogaster G-protein-coupled receptor (NPFR76F) that is activated by neuropeptide F-like peptides has been expressed in Xenopus oocytes to determine its ability to regulate heterologously expressed G-protein-coupled inwardly rectifying potassium channels. The activated receptor produced inwardly rectifying potassium currents by a pertussis toxin-sensitive G-protein-mediated pathway and the effects were reduced in the presence of proteins, such as the betaARK 1 carboxy-tail fragment and alpha-transducin, which bind G-protein betagamma-subunits. Short Drosophila NPF-like peptides were more potent than long NPF-like peptides at coupling the receptor to the activation of inwardly rectifying potassium channels. The putative endogenous short Drosophila NPF-like peptides showed agonist-specific coupling depending on whether their actions were assessed as the activation of the inwardly rectifying potassium channels or as the activation of endogenous inward chloride channels through a co-expressed promiscuous G-protein, Galpha16. As inwardly rectifying potassium channels are known to be encoded in the Drosophila genome and the NPFR76F receptor is widely expressed in the Drosophila nervous system, the receptor could function to control neuronal excitability or slow wave potential generation in the Drosophila nervous system.
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Affiliation(s)
- Vincenzina Reale
- The Signalling Programme, The Babraham Institute, Babraham, Cambridge CB2 4AT, UK
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23
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Feng G, Reale V, Chatwin H, Kennedy K, Venard R, Ericsson C, Yu K, Evans PD, Hall LM. Functional characterization of a neuropeptide F-like receptor from Drosophila melanogaster. Eur J Neurosci 2003; 18:227-38. [PMID: 12887405 DOI: 10.1046/j.1460-9568.2003.02719.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A cDNA clone encoding a seven-transmembrane domain, G-protein-coupled receptor (NPFR76F, also called GPCR60), has been isolated from Drosophila melanogaster. Deletion mapping showed that the gene encoding this receptor is located on the left arm of the third chromosome at position 76F. Northern blotting and whole mount in situ hybridization have shown that this receptor is expressed in a limited number of neurons in the central and peripheral nervous systems of embryos and adults. Analysis of the deduced amino acid sequence suggests that this receptor is related to vertebrate neuropeptide Y receptors. This Drosophila receptor shows 62-66% similarity and 32-34% identity to type 2 neuropeptide Y receptors cloned from a variety of vertebrate sources. Coexpression in Xenopus oocytes of NPFR76F with the promiscuous G-protein Galpha16 showed that this receptor is activated by the vertebrate neuropeptide Y family to produce inward currents due to the activation of an endogenous oocyte calcium-dependent chloride current. Maximum receptor activation was achieved with short, putative Drosophila neuropeptide F peptides (Drm-sNPF-1, 2 and 2s). Neuropeptide F-like peptides in Drosophila have been implicated in a signalling system that modulates food response and social behaviour. The identification of this neuropeptide F-like receptor and its endogenous ligand by reverse pharmacology will facilitate genetic and behavioural studies of neuropeptide functions in Drosophila.
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Affiliation(s)
- Guoping Feng
- Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
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Richardson J, Chatwin H, Hirasawa A, Tsujimoto G, Evans PD. Agonist-specific coupling of a cloned human alpha1A-adrenoceptor to different second messenger pathways. Naunyn Schmiedebergs Arch Pharmacol 2003; 367:333-41. [PMID: 12690424 DOI: 10.1007/s00210-003-0703-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2002] [Accepted: 01/23/2003] [Indexed: 11/30/2022]
Abstract
The agonist-specific coupling properties of the three cloned human alpha(1)-adrenoceptor subtypes have been compared, when expressed at similar levels in Chinese hamster ovary (CHO) cell lines, using noradrenaline and the (+/-)- meta- and (+/-)- para- structural isomers of octopamine as agonists. The alpha(1A)- and the alpha(1B)-adrenoceptor subtypes coupled to both the release of arachidonic acid and to the accumulation of inositol phosphates, whereas the alpha(1D)-adrenoceptor subtype only coupled effectively to the accumulation of inositol phosphates. The rank order of potencies of the three agonists tested was the same for all the three receptor subtypes when coupled to either signalling pathway: noradrenaline > meta-octopamine > para-octopamine. Meta-octopamine was a partial agonist of the alpha(1A)-adrenoceptor subtype when coupled to arachidonic acid release, whereas para-octopamine was a full agonist of this pathway. In contrast, meta-octopamine was a full agonist at the alpha(1B)-adrenoceptor subtype when coupled to arachidonic acid release, whereas para-octopamine was a partial agonist of this pathway. Neither meta-octopamine, nor para-octopamine acted as full agonists when coupling any of the three alpha(1)-adrenoceptor subtypes to the accumulation of inositol phosphates. Para-octopamine was only a weak partial agonist of this pathway for all three receptor subtypes. The results show that the modulation of arachidonic acid release and inositol 1,4,5-trisphosphate production occurs in both a subtype- and agonist-specific manner for the alpha(1A)-, alpha(1B)- and alpha(1D)-adrenoceptor subtypes. In addition, the alpha(1A)-adrenoceptor exhibits agonist-specific coupling (agonist trafficking) to the different second messenger pathways.
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Affiliation(s)
- Joanna Richardson
- The Laboratory of Receptor Signalling, The Babraham Institute, Cambridge, UK
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25
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Abstract
We report a case of anterior chest wall abscess in an immunocompetent adult by Salmonella enteritidis, whose food was contaminated by bird droppings. The patient did not have any gastrointestinal symptoms. Surgical excision followed by antibiotics (cefuroxime and ciprofloxacin) successfully treated the condition. To our knowledge, this is the first reported case of anterior chest wall abscess caused by S. enteritidis in an immunocompetent adult without any preceding gastrointestinal symptoms. We feel that the contamination of his food with the bird droppings was a risk factor.
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Affiliation(s)
- S K Gupta
- Department of Orthopaedics and Microbiology, Royal Glamorgan Hospital, Ynysmaerdy, Llantrisant, CF72 8XR, UK.
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Chatwin HM, Rudling JE, Patel D, Reale V, Evans PD. Site-directed mutagenesis studies on the Drosophila octopamine/tyramine receptor. Insect Biochem Mol Biol 2003; 33:173-184. [PMID: 12535676 DOI: 10.1016/s0965-1748(02)00188-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The cloned Drosophila octopamine/tyramine receptor can be coupled to second messenger pathways in an agonist-specific fashion by the endogenously occurring biogenic amines, octopamine and tyramine, when expressed in Chinese hamster ovary cells. We have mutated to alanine a range of receptor amino acids that could potentially form hydrogen bonds with the beta-hydroxyl group of octopamine based on homologies with alpha- and beta-adrenergic receptor subtypes. After stable expression of the mutant receptors in CHO cells we have compared the ability of octopamine and tyramine to displace [(3)H]yohimbine binding to membrane fractions from the mutant cell lines with their ability to modulate adenylyl cyclase activity in intact cells. The results suggest that none of the mutated amino acids residues, at least in isolation, are likely to be involved in interactions with the beta-hydroxyl group of the octopamine side chain. It is possible that amino acids not mutated in the present study are somehow involved in this interaction. Alternatively, it is also possible that the beta-hydroxyl group of the octopamine side chain is capable of interacting with more than one of the amino acids mutated in the present study.
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Affiliation(s)
- Heather M Chatwin
- The Laboratory of Receptor Signalling, The Babraham Institute, Babraham, Cambridge CB2 4AT, UK
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Kiguchi M, Evans PD, Ekstedt J, Williams RS, Kataoka Y. Improvement of the durability of clear coatings by grafting of UV-absorbers on to wood. ACTA ACUST UNITED AC 2001. [DOI: 10.1007/bf02700407] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Hannan F, Evans PD. A locust type 1 ADP-ribosylation factor (lARF1)* is 100% identical in amino acid sequence to Drosophila ARF1 despite obvious DNA sequence divergence. Insect Mol Biol 2000; 9:559-563. [PMID: 11122465 DOI: 10.1046/j.1365-2583.2000.00219.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The cDNA of a type 1 ADP-ribosylation factor (ARF) from the desert locust, Locusta migratoria was cloned, sequenced and compared to ARF1 genes of other species. The locust ARF1 protein is 100% identical with the ARF1 protein of the fruit fly Drosophila melanogaster even though the DNA sequences are only 79% identical. The significance of this finding in relation to the considerable evolutionary distance between hemimetabolous and holometabolous insects is discussed.
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Affiliation(s)
- F Hannan
- Babraham Institute Laboratory of Molecular Signalling, Zoology Department, Downing Street, Cambridge, UK.
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Abstract
The agonist-specific coupling properties of the three cloned human alpha(2)-adrenoceptor subtypes have been compared, when expressed at similar levels in Chinese hamster ovary (CHO) cell lines, using noradrenaline and (+/-)-meta-octopamine as agonists. Noradrenaline can couple the receptor to both the inhibition and stimulation of forskolin-stimulated cyclic AMP production in all three receptor subtypes, with the relative strength of the coupling to the pathways varying for each of the receptor subtypes. meta-Octopamine selectively couples the alpha(2A)-adrenoceptor only to the inhibition of forskolin-stimulated cyclic AMP production. However, meta-octopamine couples the alpha(2B)- and alpha(2C)-adrenoceptors to both the inhibition and stimulation of forskolin-stimulated cyclic AMP production. The relative potency of meta-octopamine to noradrenaline varies between the different alpha(2)-adrenoceptor subtypes. The effects of meta-octopamine are around two orders of magnitude less potent than those of noradrenaline on both the alpha(2A)- and alpha(2B)-adrenoceptor subtypes. In contrast, in the case of the alpha(2C)-adrenoceptor, meta-octopamine is only one order of magnitude less potent than noradrenaline in the stimulation of forskolin-stimulated cyclic AMP production and, in addition, is equipotent with noradrenaline in the inhibition of forskolin-stimulated cyclic AMP production and has an increased maximal response. This raises the possibility that meta-octopamine may have physiologically important actions via alpha(2C)-adrenoceptors in vivo. The results show that the modulation of cyclic AMP production occurs in both a subtype- and agonist-specific manner for alpha(2A)-adrenoceptors and in a subtype specific manner for alpha(2B)- and alpha(2C)-adrenoceptors.
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Affiliation(s)
- Jane E Rudling
- The Babraham Institute Laboratory of Receptor Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
| | - Jo Richardson
- The Babraham Institute Laboratory of Receptor Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
| | - Peter D Evans
- The Babraham Institute Laboratory of Receptor Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
- Author for correspondence:
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Hucklebridge F, Lambert S, Clow A, Warburton DM, Evans PD, Sherwood N. Modulation of secretory immunoglobulin A in saliva; response to manipulation of mood. Biol Psychol 2000; 53:25-35. [PMID: 10876063 DOI: 10.1016/s0301-0511(00)00040-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Secretory immunoglobulin A (sIgA) measured in saliva, an index of mucosal immunity, has repeatedly been shown to be sensitive to psychological variables. Chronic stress is downregulatory whereas an acute psychological challenge induces mobilisation. We examined whether an acute manipulation of mood to induce negative hedonic tone would be downregulatory, as in the chronic stress paradigm and further, whether induction of positive mood might have opposite effects. Two separate experiments were conducted. In the first, mood manipulation was by mental recall and in the second by music. For both sIgA concentration and sIgA secretion rate there was a significant elevation in response to the mood manipulation by recall regardless of hedonic tone. There was some evidence that for sIgA secretion rate the response was more pronounced for positive mood. Mood induction by music also resulted in significant elevations in sIgA concentration and secretion rate and responses were not distinguished by mood valence. None of the mood induction procedures was associated with changes in free cortisol. In these studies, we found no evidence that transient lowering of mood was downregulatory for salivary sIgA. The predominant finding was of sIgA mobilisation.
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Affiliation(s)
- F Hucklebridge
- Psychophysiology and Stress Research Group, Department of Biomedical Sciences, University of Westminster, London, UK.
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Jeeves M, Evans PD, Parslow RA, Jaseja M, Hyde EI. Studies of the Escherichia coli Trp repressor binding to its five operators and to variant operator sequences. Eur J Biochem 1999; 265:919-28. [PMID: 10518785 DOI: 10.1046/j.1432-1327.1999.00792.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Escherichia coli Trp repressor binds to promoters of very different sequence and intrinsic activity. Its mode of binding to trp operator DNA has been studied extensively yet remains highly controversial. In order to examine the selectivity of the protein for DNA, we have used electromobility shift assays (EMSAs) to study its binding to synthetic DNA containing the core sequences of each of its five operators and of operator variants. Our results for DNA containing sequences of two of the operators, trpEDCBA and aroH are similar to those of previous studies. Up to three bands of lower mobility than the free DNA are obtained which are assigned to complexes of stoichiometry 1 : 1, 2 : 1 and 3 : 1 Trp repressor dimer to DNA. The mtr and aroL operators have not been studied previously in vitro. For DNA containing these sequences, we observe predominantly one retarded band in EMSA with mobility corresponding to 2 : 1 complexes. We have also obtained retardation of DNA containing the trpR operator sequence, which has only been previously obtained with super-repressor Trp mutants. This gives bands with mobilities corresponding to 1 : 1 and 2 : 1 complexes. In contrast, DNA containing containing a symmetrized trpR operator sequence, trpRs, gives a single retarded band with mobility corresponding solely to a 1 : 1 protein dimer-DNA complex. Using trpR operator variants, we show that a change in a single base pair in the core 20 base pairs can alter the number of retarded DNA bands in EMSA and the length of the DNase I footprint observed. This shows that the binding of the second dimer is sequence selective. We propose that the broad selectivity of Trp repressor coupled to tandem 2 : 1 binding, which we have observed with all five operator sequences, enables the Trp repressor to bind to a limited number of sites with diverse sequences. This allows it to co-ordinately control promoters of different intrinsic strength. This mechanism may be of importance in a number of promoters that bind multiple effector molecules.
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Affiliation(s)
- M Jeeves
- School of Biochemistry, University of Birmingham, UK
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Rudling JE, Kennedy K, Evans PD. The effect of site-directed mutagenesis of two transmembrane serine residues on agonist-specific coupling of a cloned human alpha2A-adrenoceptor to adenylyl cyclase. Br J Pharmacol 1999; 127:877-86. [PMID: 10433494 PMCID: PMC1566090 DOI: 10.1038/sj.bjp.0702614] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. The effects of substitution of the Ser200 and Ser204 residues with alanine on the signalling properties of the cloned human alpha2A-adrenoceptor, stably expressed in Chinese hamster ovary (CHO) cell lines, have been investigated using noradrenaline and the structural isomers of octopamine. 2. The Ser-->Ala200 or the Ser-->Ala204 mutant forms of the alpha2A-adrenoceptor, when expressed in cells in the absence of pertussis toxin pretreatment, are two orders of magnitude more sensitive to inhibition of cyclic AMP production by (+/-)-para-octopamine and (+/-)-meta-octopamine, respectively, than cells expressing the wild-type receptor. Binding studies indicate that the effects are not due to an increased agonist affinity for the mutant receptors and that they are likely to be due to agonist-mediated conformational changes in receptor structure. 3. After incubation with pertussis toxin, (+/-)-meta-octopamine (100 microM and above) produced a stimulation of cyclic AMP levels in cells expressing the Ser-->Ala204 mutant form of the alpha2A-adrenoceptor but showed no stimulation in cells expressing the Ser-->Ala200 mutant receptor. Under these conditions (+/-)-para-octopamine did not produce any increases in cyclic AMP production in cells expressing either of the mutant receptor forms or the wild-type receptor. 4. The results emphasise the importance of the Ser200 and Ser204 residues of the alpha2A-adrenoceptor in exerting an inhibitory influence on the ability of (+/-)-para-octopamine and (+/-)-meta-octopamine respectively, to induce a receptor-agonist conformation capable of inhibiting forskolin-stimulation of cyclic AMP levels. 5. It is clear that Ser204 also prevents meta-octopamine from generating a receptor-agonist conformation that can increase cyclic AMP levels, emphasising the importance of this residue in the agonist-specific coupling of this receptor to different second messenger systems.
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Affiliation(s)
- Jane E Rudling
- The Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
| | - Karen Kennedy
- The Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
| | - Peter D Evans
- The Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
- Author for correspondence:
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Germon TJ, Evans PD, Barnett NJ, Wall P, Manara AR, Nelson RJ. Cerebral near infrared spectroscopy: emitter-detector separation must be increased. Br J Anaesth 1999; 82:831-7. [PMID: 10562774 DOI: 10.1093/bja/82.6.831] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have compared the effect of increasing optode separation (range 0.7-5.5 cm) on the sensitivity of near infrared spectroscopy (NIRS) to discrete reductions in scalp and cerebral oxygenation in 10 healthy men (mean age 32, range 26-39 yr) using multichannel NIRS. During cerebral oligaemia (a mean reduction in middle cerebral artery flow velocity of 47%) induced by a mean reduction in end-tidal PCO2 of 2.4 kPa, the decrease in oxyhaemoglobin detected by NIRS became significantly greater with increasing optode separation (P < 0.0001). In response to scalp hyperaemia induced by inflation and release of a pneumatic scalp tourniquet, increases in oxyhaemoglobin became significantly smaller with increasing optode separation (P < 0.0002). These results are consistent with theoretical models of the behaviour of NIR light in the adult head and support the concept of using multi-detector NIRS to separate intra- and extracranial NIR signal changes. However, the emitter-detector separation used by currently available cerebral oximeters is not large enough to provide optimal spatial resolution.
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Affiliation(s)
- T J Germon
- Department of Neurosurgery, Frenchay Hospital, Bristol, UK
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Evans PD, Reale V, Merzon RM, Villegas J. A comparison of the release of a vasoactive-intestinal-peptide-like peptide and acetylcholine in the giant axon-Schwann cell preparation of the tropical squid Sepioteuthis sepioidea. J Exp Biol 1999; 202:417-428. [PMID: 9914149 DOI: 10.1242/jeb.202.4.417] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A vasoactive intestinal peptide (VIP)-like peptide is released by axonal stimulation in the giant axon-Schwann cell preparation from the tropical squid Sepioteuthis sepioidea. It is also released by direct application of l-glutamate, the giant axon-Schwann cell signalling molecule in this preparation. The release of the peptide parallels the release of acetylcholine from the Schwann cells themselves in this preparation in a number of different ways. The release of both acetylcholine and the VIP-like peptide have the same threshold (between 2×10(−10) and 5×10(−10)mol l-1) for l-glutamate application and the same recovery time after inhibition of release by exposure of the preparation to a prolonged pulse of l-glutamate. A prolonged l-glutamate pulse of 10(−8)mol l-1 releases both substances for as long as the pulse is applied to the preparation, whereas a prolonged pulse of 10(−9)mol l-1 l-glutamate releases acetylcholine in the same way but releases the VIP-like peptide only transiently. The VIP-like peptide is likely to be co-released with acetylcholine from the Schwann cells.
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Affiliation(s)
- PD Evans
- The Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK and Centro de Neurociencias, Instituto International de Estudios Avanzados (IDEA), Apartado 17606, Parque Central, Caracas 1015-A, Venezuela.
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Abstract
The circadian pattern of free cortisol, measured in saliva, was monitored in normal healthy adults (N=41) for the first half hour immediately after awakening and in a smaller group (N=8) at timed intervals throughout the day. The endogenous inhibitor of monoamine oxidase A (MAO-AI) was measured in the same saliva samples in order to explore the relationship between circadian activation of the hypothalamic-pituitary-adrenocortical (HPA) axis and MAO-AI. A marked elevation of salivary cortisol was recorded in the first half hour immediately after awakening resulting in a two to three fold increase from the first awakening level. By contrast MAO-AI was highest immediately upon awakening and fell subsequently. Hence the cortisol response to awakening is preceded by heightened MAO-AI. Moreover those subjects who showed more persistently elevated MAO-AI were characterised by a more pronounced cortisol response. An association between MAO-AI and cortisol was also manifest in the diurnal pattern recorded at timed intervals throughout the day. The decline of salivary cortisol from the morning acrophase to the evening nadir was paralleled by MAO-AI. Both patterns of decline were significant (P< 0.01). Taken together with previously reported psychological stress studies these findings suggest a possible relationship between MAO-AI and HPA activity.
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Affiliation(s)
- F Hucklebridge
- School of Biosciences, University of Westminster, London, UK.
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Howell KM, Evans PD. The characterization of presynaptic octopamine receptors modulating octopamine release from an identified neurone in the locust. J Exp Biol 1998; 201 (Pt 13):2053-60. [PMID: 9622577 DOI: 10.1242/jeb.201.13.2053] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Octopamine release has been demonstrated from the dorsal unpaired median neurone to the locust extensor-tibiae muscle (DUMETi) in response to high-[K+] saline. Here, we provide evidence for the existence of presynaptic inhibitory autoreceptors for octopamine on the DUMETi terminals and report on their pharmacological profile. Octopamine release was initiated by exposure to high-[K+] saline (0. 1 mol l-1) and measured using a radioenzyme assay for octopamine. Octopamine receptor antagonists (10(-4 )mol l-1) potentiated the high-[K+]-mediated release of octopamine with the following rank order of potency: phentolamine = metoclopramide > mianserin = chlorpromazine > cyproheptadine > yohimbine. Octopamine receptor agonists (10(-4 )mol l-1) inhibited the high-[K+]-mediated release of octopamine with the following rank order of potency: naphazoline > tolazoline > clonidine. Thus, the octopamine autoreceptors on the DUMETi terminals are much closer pharmacologically to the pre-and postsynaptic OCTOPAMINE2 receptors in the locust extensor-tibiae muscle preparation than to the OCTOPAMINE3 receptors from the locust central nervous system. The results suggest that there is likely to be more than one type of insect neuronal octopamine receptor. It is also likely that presynaptic modulation of octopamine release may be confined to octopamine receptors since a wide range of other putative modulatory substances did not produce this effect.
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Affiliation(s)
- KM Howell
- The Babraham Institute, Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
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Germon TJ, Evans PD, Manara AR, Barnett NJ, Wall P, Nelson RJ. Sensitivity of near infrared spectroscopy to cerebral and extra-cerebral oxygenation changes is determined by emitter-detector separation. J Clin Monit Comput 1998; 14:353-60. [PMID: 9951761 DOI: 10.1023/a:1009957032554] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To examine the effect of two emitter-detector separations (2.7 and 5.5 cm) on the detection of changes in cerebral and extra-cerebral tissue oxygenation using near infrared spectroscopy (NIRS). METHODS Two NIR detectors were placed on the scalp 2.7 and 5.5 cm from a single NIR emitter. Changes in deoxyhaemoglobin (HHb), oxyhaemoglobin (O2Hb),oxidised cytochrome C oxidase (Cyt) and total haemoglobin (tHb) were recorded from each detector during the induction of cerebral oligaemia (transition from hypercapnia to hypocapnia) and scalp hyperaemia (following release of a scalp tourniquet). RESULTS Cerebral oligaemia (mean decrease in middle cerebral artery blood flow velocity of 44%) induced by a mean reduction in end tidal CO2 of 18 mmHg was accompanied by a significant increase in the spectroscopic signal for HHb and a decrease in the O2Hb signal. The signal change per unit photon path length detected at 5.5 cm was significantly greater for HHb (p = 0.007) than that detected at 2.7 cm. In contrast, the increase in all chromophores detected at 5.5 cm during scalp hyperaemia was significantly less than that detected at 2.7 cm (p<0.001). CONCLUSIONS The differing sensitivity of the proximal and distal channels to changes in cerebral and extracerebral oxygenation is compatible with theoretical models of NIR light transmission in the adult head and may provide a basis for spatially resolving these changes. The optimal emitter-detector separation for adult NIRS requires further investigation and may differ between individuals.
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Affiliation(s)
- T J Germon
- Department of Neurosurgery, Frenchay Hospital, Bristol, UK
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Clow A, Doyle A, Hucklebridge F, Carroll D, Ring C, Shrimpton J, Willemsen G, Evans PD. Endogenous monoamine oxidase A inhibitory activity (tribulin), measured in saliva, is related to cardiovascular reactivity in normal individuals. J Neural Transm Suppl 1998; 52:71-7. [PMID: 9564609 DOI: 10.1007/978-3-7091-6499-0_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Salivary monoamine oxidase A inhibitory activity (MAO-AI), mean arterial blood pressure (MAP) and heart rate (HR) were determined simultaneously in healthy male students (n = 13) at rest, before a mild psychological stressor, twice during the task and 18 minutes after the end of the task. The sample as a whole showed significant differences in MAP and HR across occasions (respectively, p < 0.001 for both). Salivary MAO-AI could distinguish novice and experienced game players (p < 0.02) and was consistently positively correlated with MAP (r = 0.58, p < 0.05 on occasion 2). Pre-task measures of MAO-AI for an increased sample (n = 18) were associated with higher MAP (but not HR) throughout the experiment (p < 0.05). Those subject with falling MAO-AI profiles from task to recovery showed significantly greater simultaneous decline in HR than those with a rising MAO-AI profile (p < 0.05).
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Affiliation(s)
- A Clow
- Psychophysiology and Stress Research Group, University of Westminster, London, United Kingdom
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Abstract
The role of particular residues of the PvuII endonuclease in DNA binding and cleavage was studied by mutational analysis using a number of in vivo and in vitro approaches. While confirming the importance of residues predicted to be involved directly in function by the crystal structure, the analysis led to several striking results. Aspartate 34, which contacts the central base pair of the PvuII site (5'-CAGCTG-3') through the minor groove, plays a critical role in binding specificity. A D34G mutant binds with high affinity to any of the sequences in the set CANNTG, although its low level of cleavage activity acts only on the wild-type site. In addition, a His to Ala mutation at the residue that contacts the central G and is predicted to be blocked by PvuII methylation still requires the PvuII methylase to be maintained in vivo, arguing against this hypothesis as the only mechanism for methylation protection. Finally, four of the five mutations that reduce cleavage activity while still exhibiting binding in the gel shift assay are at residues that form DNA- or subunit-subunit contacts rather than in the catalytic center. This provides further evidence for a strong linkage between specific binding and catalysis.
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Affiliation(s)
- H G Nastri
- New England Biolabs Incorporated, Beverly, Massachusetts 01915, USA
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Abstract
The expression of a cloned Drosophila octopamine/tyramine receptor (OctyR99AB) is described in Xenopus oocytes. Agonist stimulation of OctyR99AB receptors increased intracellular Ca2+ levels monitored as changes in the endogenous inward Ca2+-dependent chloride current. The receptor is preferentially sensitive to biogenic amines with a single hydroxyl on the aromatic ring. The G-protein, Galphai, appears to be involved in the coupling of the receptor to the production of intracellular calcium signals, since the effect is pertussis-toxin sensitive and is blocked or substantially reduced in antisense knockout experiments using oligonucleotides directed against Galphai but not by those directed against Galphao, Galphaq and Galpha11. The increase in intracellular calcium levels induced by activation of the OctyR99AB receptor can potentiate the ability of activation of a co-expressed beta2-adrenergic receptor to increase oocyte cyclic AMP levels. A comparison of the pharmacological coupling of OctyR99AB to different second messenger systems when expressed in Xenopus oocytes with previous studies on the expression of the receptor in a Chinese hamster ovary cell line suggests that the property of agonist-specific coupling of the receptor to different second messenger systems may be cell-specific, depending upon the G-protein environment of any particular cell type.
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Affiliation(s)
- V Reale
- The Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, UK
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Reale V, Hannan F, Hall LM, Evans PD. Agonist-specific coupling of a cloned Drosophila melanogaster D1-like dopamine receptor to multiple second messenger pathways by synthetic agonists. J Neurosci 1997; 17:6545-53. [PMID: 9254667 PMCID: PMC6573129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/1997] [Revised: 06/10/1997] [Accepted: 06/12/1997] [Indexed: 02/05/2023] Open
Abstract
The mechanism of coupling of a cloned Drosophila D1-like dopamine receptor, DopR99B, to multiple second messenger systems when expressed in Xenopus oocytes is described. The receptor is coupled directly to the generation of a rapid, transient intracellular Ca2+ signal, monitored as changes in inward current mediated by the oocyte endogenous Ca2+-activated chloride channel, by a pertussis toxin-insensitive G-protein-coupled pathway. The more prolonged receptor-mediated changes in adenylyl cyclase activity are generated by an independent G-protein-coupled pathway that is pertussis toxin-sensitive but calcium-independent, and Gbetagamma-subunits appear to be involved in the transduction of this response. This is the first evidence for the direct coupling of a cloned D1-like dopamine receptor both to the activation of adenylyl cyclase and to the initiation of an intracellular Ca2+ signal. The pharmacological profile of both second messenger effects is identical for a range of naturally occurring catecholamine ligands (dopamine > norepinephrine > epinephrine) and for the blockade of dopamine responses by a range of synthetic antagonists. However, the pharmacological profiles of the two second messenger responses differ for a range of synthetic agonists. Thus, the receptor exhibits agonist-specific coupling to second messenger systems for synthetic agonists. This feature could provide a useful tool in the genetic analysis of the roles of the multiple second messenger pathways activated by this receptor, given the likely involvement of dopamine in the processes of learning and memory in the insect nervous system.
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Affiliation(s)
- V Reale
- The Babraham Institute Laboratory of Molecular Signaling, Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, United Kingdom
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Abstract
1. In this study we have compared the abilities of the enantiomers of the structural isomers of the phenolamines, octopamine and synephrine, and the catecholamines, noradrenaline and adrenaline, to couple selectively a human cloned alpha 2A-adrenoceptor, stably expressed in a Chinese hamster ovary (CHO) cell line, to G-protein linked second messenger pathways mediating an increase and a decrease in cyclic AMP production. 2. The catecholamines couple the alpha 2A-adrenoceptor to both an increase and a decrease in the rate of cyclic AMP production. In the absence of pertussis toxin pretreatment both catecholamines tested showed a dose-dependent decrease with a maximum at 100 nM. After pertussis toxin pretreatment they both produced a dose-dependent increase in cyclic AMP production with a maximum at 10 microM. 3. The phenolamines, octopamine and synephrine were only able to couple the alpha 2A-adrenoceptor to a dose-dependent decrease in cyclic AMP production at concentrations up to 1 mM, with the synephrine isomers being more potent than the corresponding octopamine isomers. The meta-isomers of both phenolamines were more potent than the corresponding para-isomers and the (-)-enantiomers were more potent than the (+)-enantiomers. Thus, (-)-meta-synephrine [(-)-phenylephrine] was the most effective isomer tested with an observable decrease occurring between 100 nM and 1 microM. 4. The effects of octopamine and the catecholamines on the decrease in cyclic AMP production were additive at submaximal concentrations, whilst octopamine reduced the stimulant effect of submaximal concentrations of noradrenaline on cyclic AMP production after pertussis toxin pretreatment. 5. The time courses of the inhibitory effects of both meta-octopamine and noradrenaline were parallel and peaked after a 1 min exposure to the agonist. In contrast, the stimulant effects of noradrenaline after pertussis toxin pretreatment were of a much slower time course with a maximum effect occurring after a 5 min incubation period. 6. Since octopamine and synephrine occur naturally in, and are co-released with catecholamines from, mammalian tissues, the results of the present study suggest that the human cloned alpha 2A-adrenoceptor can be coupled selectively by different endogenous agonists to G-protein pathways mediating the regulation of adenylyl cyclase activity.
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Affiliation(s)
- C N Airriess
- Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge
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Richardson JM, Evans PD, Homans SW, Donohue-Rolfe A. Solution structure of the carbohydrate-binding B-subunit homopentamer of verotoxin VT-1 from E. coli. Nat Struct Biol 1997; 4:190-3. [PMID: 9164458 DOI: 10.1038/nsb0397-190] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Clow A, Patel S, Najafi M, Evans PD, Hucklebridge F. The cortisol response to psychological challenge is preceded by a transient rise in endogenous inhibitor of monoamine oxidase. Life Sci 1997; 61:567-75. [PMID: 9247326 DOI: 10.1016/s0024-3205(97)00416-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The salivary cortisol response to an acute psychological stress challenge was investigated in normal male undergraduate students. A modified version of the Trier Social Stress Test (TSST) was used and saliva collected on 6 occasions before during and after the stress challenge. Control subjects were allowed to read quietly. As expected the cortisol response in experimental subjects was robust and peaked 12 minutes after the end of the stress. Endogenous monoamine oxidase A inhibitory activity (MAO-AI) was measured in the same saliva samples. MAO-AI also changed in response to the stress challenge, peaking in the saliva sample collected immediately after the stress challenge, 12 minutes prior to the cortisol peak sample. Furthermore the degree of increase in salivary MAO-AI was found to predict the degree of cortisol increase in the test subjects (r=0.76; n=14; p<0.001). These results are consistent with the hypothesis that elevated central monoamines, driven by inhibition of their main metabolic enzyme, can activate the hypothalamic-pituitary-adrenal (HPA) axis in the stress response. This finding lends further support to the notion that endogenous generation of MAO-AI is a normal homeostatic regulatory mechanism.
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Affiliation(s)
- A Clow
- The Psychophysiology and Stress Research Group, School of Biological and Health Sciences, University of Westminster, London.
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Abstract
To understand the specificity of the Escherichia coli Trp repressor for its operators, we have begun to study complexes of the protein with alternative DNA sequences, using 1H-NMR spectroscopy. We report here the 1H-NMR chemical shifts of a 20-bp oligodeoxynucleotide containing the sequence of a symmetrised form of the trpR operator in the presence and absence of the holorepressor. Deuterated protein was used to assign the spectrum of the oligodeoxynucleotide in a 37-kDa complex with the Trp holorepressor. Many of the resonances of the DNA shift on binding to the protein, which suggests changes in conformation throughout the sequence. The largest changes in shifts for the aromatic protons in the major groove are for A15 and G16, which are thought to hydrogen bond to the protein, possibly via water molecules. We have also examined the effect of DNA binding on the corepressor, tryptophan, in this complex. The indole proton resonance of the tryptophan undergoes a downfield shift of 1.2 ppm upon binding of DNA. This large shift is consistent with hydrogen bonding of the tryptophan to the phosphate backbone of the trpR operator DNA, as in the crystal structure of the holoprotein with the trp operator.
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Affiliation(s)
- P D Evans
- School of Biochemistry, University of Birmingham, Edgbaston, UK
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Feng G, Hannan F, Reale V, Hon YY, Kousky CT, Evans PD, Hall LM. Cloning and functional characterization of a novel dopamine receptor from Drosophila melanogaster. J Neurosci 1996; 16:3925-33. [PMID: 8656286 PMCID: PMC6578617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1995] [Revised: 03/26/1996] [Accepted: 04/02/1996] [Indexed: 02/01/2023] Open
Abstract
A cDNA clone is described that encodes a novel G-protein-coupled dopamine receptor (DopR99B) expressed in Drosophila heads. The DopR99B receptor maps to 99B3-5, close to the position of the octopamine/tyramine receptor gene at 99A10-B1, suggesting that the two may be related through a gene duplication. Agonist stimulation of DopR99B receptors expressed in Xenopus oocytes increased intracellular Ca2+ levels monitored as changes in an endogenous inward Ca2+-dependent chloride current. In addition to initiating this intracellular Ca2+ signal, stimulation of DopR99B increased cAMP levels. The rank order of potency of agonists in stimulating the chloride current is: dopamine > norepinephrine > epinephrine > tyramine. Octopamine and 5-hydroxytryptamine are not active (< 100 microM). This pharmacological profile plus the second-messenger coupling pattern suggest that the DopR99B receptor is a D1-like dopamine receptor. However, the hydrophobic core region of the DopR99B receptor shows almost equal amino acid sequence identity (40-48%) with vertebrate serotonergic, alpha 1- and beta-adrenergic, and D1-like and D2-like dopaminergic receptors. Thus, this Drosophila receptor defines a novel structural class of dopamine receptors. Because DopR99B is the second dopamine receptor cloned from Drosophila, this work establishes dopamine receptor diversity in a system amenable to genetic dissection.
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Affiliation(s)
- G Feng
- Department of Biochemical Pharmacology, State University of New York at Buffalo 14260-1200, USA
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Swales LS, Evans PD. Distribution of SchistoFLRFamide-like immunoreactivity in the adult ventral nervous system of the locust, Schistocerca gregaria. Cell Tissue Res 1995; 281:339-48. [PMID: 7648627 DOI: 10.1007/bf00583402] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
SchistoFLRFamide (PDVDHVFLRF-NH2) is one of the major endogenous neuropeptides of the FMRFamide family found in the nervous system of the locust, Schistocerca gregaria. To gain insights into the potential physiological roles of this neuropeptide we have examined the distribution of SchistoFLRFamide-like immunoreactivity in the ventral nervous system of adult locusts by use of a newly developed N-terminally specific antibody. SchistoFLRFamide-like immunoreactivity in the ventral nerve cord is found in a subgroup of the neurones that are immunoreactive to an antiserum raised against bovine pancreatic polypeptide (BPP). In the suboesophageal ganglion three groups of cells stain, including one pair of large posterior ventral cells. These cells are the same size, in the same location in the ganglion and have the same branching pattern as a pair of BPP immunoreactive cells known to innervate the heart and retrocerebral glandular complex of the locust. In the thoracic and abdominal ganglia two and three sets of cells, respectively, stain with both the SchistoFLRFamide and BPP antisera. In the abdominal ganglia the immunoreactive cells project via the median nerves to the intensely immunoreactive neurohaemal organs.
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Affiliation(s)
- L S Swales
- Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, UK
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Evans PD, Cook SN, Riggs PD, Noren CJ. LITMUS: multipurpose cloning vectors with a novel system for bidirectional in vitro transcription. Biotechniques 1995; 19:130-5. [PMID: 7669286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We describe the construction and uses of a set of four multipurpose cloning vectors: LITMUS 28, 29, 38 and 39. The vectors feature the high-copy pUC origin and an M13 origin for single-stranded DNA production as well as polylinker sites for most commercially available restriction enzymes that recognize nondegenerate hexanucleotide sites and yield 4-base sticky ends upon cleavage. Sites are arranged, without overlaps, to permit linker addition to blunt-ended fragments and unidirectional nested deletions and are within the lacZ alpha gene to facilitate blue-white screening. Finally, the polylinkers are flanked by a pair of opposing modified T7 promoters to allow in vitro transcription of either strand of a cloned insert with T7 RNA polymerase. Selective unidirectional transcription from one promoter is achieved by cleaving the other at an internal restriction site (AflII or SpeI). Both modified promoters are fully active under standard RNA probe synthesis conditions. In Southern blots of Dirofilaria immitis genomic DNA, an RNA probe prepared from LITMUS performed equivalently to the same RNA probe made from a wild-type promoter vector and a DNA probe prepared by random priming.
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Affiliation(s)
- P D Evans
- New England Biolabs, Inc., Beverly, MA, USA
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Swales LS, Evans PD. Distribution of myomodulin-like immunoreactivity in the brain and retrocerebral complex of the locust, Schistocerca gregaria. J Comp Neurol 1995; 353:407-14. [PMID: 7751439 DOI: 10.1002/cne.903530308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The distribution of myomodulin-like immunoreactivity is described for the brain and retrocerebral complex of an insect, the locust, Schistocerca gregaria. The locust brain contains 70-100 neuronal cell bodies and numerous neuropilar processes exhibiting myomodulin-like immunoreactivity. The most marked feature of the staining is a group of lateral tritocerebral neurones that form a highly immunoreactive tract that gives rise to a complex neuropile of stained processes in the dorsal tritocerebrum. This tract continues dorsally and bifurcates into a major branch that exists the brain via nervi corpora cardiaca 1 (NCC1) to innervate the corpora cardiaca and the corpora allata. A minor branch, consisting of several individual axons, combines with immunoreactive processes from the ventral nerve cord and generates a complex immunoreactive neuropile in the anterior and posterior regions of the protocerebrum. Immunoreactive processes are also found in the structured neuropile of the central body complex. Immunoreactive cell bodies are also found in the antennal lobes, in the lateral margins of the protocerebrum, in the optic lobes, and in a few cells in the pars intercerebralis. The results suggest that myomodulin-like neuropeptides may play roles as central neurotransmitters or neuromodulators in insects as well as being released into the circulation as neurohormones or acting as releasing agents for neurohormones in neurohaemal areas. They also further strengthen the idea that myomodulins, which were first identified in molluscs, may represent another interphyletic family of neuropeptides.
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Affiliation(s)
- L S Swales
- Babraham Institute Laboratory of Molecular Signalling, Department of Zoology, University of Cambridge, United Kingdom
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Evans PD, Marshall PD, McDonnell B, Richards J, Evans EJ. Radiologic study of the accuracy of a tibial intramedullary cutting guide for knee arthroplasty. J Arthroplasty 1995; 10:43-6. [PMID: 7730829 DOI: 10.1016/s0883-5403(05)80099-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Twenty-one caucasian, adult cadaveric tibiae were prepared as for knee arthroplasty using an intramedullary cutting guide. The instrumentation was used to produce slots in the proximal tibia into which Kirschner wires were placed as radio-opaque markers for subsequent anteroposterior and lateral radiographs. The anatomic axis of the tibia and lines perpendicular to the wire markers were drawn on the radiographs and the angle between the two lines was measured to assess the accuracy of the cuts. Seventy-one percent of the tibial cuts were found to be within 2 degrees of the anatomic axis on the anteroposterior radiograph (mean, 2.1 degrees), while on the lateral radiograph, 81% of the cuts were within 2 degrees (mean, 1.8 degrees). There was a significant tendency to position the bone cuts in varus (P < .05), although this did not correlate with varus or valgus deformity of the bones. There was no consistent tendency to anterior or posterior tilt on the lateral radiograph (P > .05). The results compare favorably with those obtained from a specialist unit using an extramedullary alignment system. The authors conclude that the tibial intramedullary guide can lead to preparation of the proximal tibia for knee arthroplasty as accurately as the conventional extramedullary system.
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Affiliation(s)
- P D Evans
- Department of Orthopaedic Surgery, University of Wales, College of Cardiff, United Kingdom
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