1
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Hanley MR, Cheung WT, Hawkins P, Poyner D, Benton HP, Blair L, Jackson TR, Goedert M. The mas oncogene as a neural peptide receptor: expression, regulation and mechanism of action. CIBA FOUNDATION SYMPOSIUM 2007; 150:23-38; discussion 38-46. [PMID: 2197067 DOI: 10.1002/9780470513927.ch3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The human mas oncogene, which renders transfected NIH/3T3 cells tumorigenic, was identified as a subtype of angiotensin receptor by transient expression in Xenopus oocytes and stable expression in the mammalian neuronal cell line, NG115-401L. The mas receptor preferentially recognizes angiotensin III, and is expressed at high levels in brain. The mas/angiotensin receptor functions through the breakdown of inositol lipids and can drive DNA synthesis, unlike another inositol-linked peptide receptor, that for bradykinin. Comparative analysis of several early biochemical events elicited by either angiotensin or bradykinin stimulation of mas-transfected cells has not indicated a specific difference correlated with mitogenic activity. In particular, the inositol lipid kinase, phosphatidylinositol-3-kinase, thought to be involved in the mitogenic mechanism of platelet-derived growth factor receptors, is unaffected by activation of mas. These results have shown that a proto-oncogene encodes a neural peptide receptor, indicating that peptide receptors may be involved in differentiation and proliferation processes, as are other identified proto-oncogenes.
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Affiliation(s)
- M R Hanley
- MRC Molecular Neurobiology Unit, MRC Centre, Cambridge, UK
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2
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Mohr E, Meyerhof W, Richter D. The hypothalamic hormone oxytocin: from gene expression to signal transduction. Rev Physiol Biochem Pharmacol 2005; 121:31-48. [PMID: 1336619 DOI: 10.1007/bfb0033193] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- E Mohr
- Institut für Zellbiochemie und klinische Neurobiologie, UKE, Universität Hamburg, FRG
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3
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Meeusen T, Mertens I, De Loof A, Schoofs L. G Protein-Coupled Receptors in Invertebrates: A State of the Art. INTERNATIONAL REVIEW OF CYTOLOGY 2003; 230:189-261. [PMID: 14692683 DOI: 10.1016/s0074-7696(03)30004-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
G protein-coupled receptors (GPCRs) constitute one of the largest and most ancient superfamilies of membrane-spanning proteins. We focus on neuropeptide GPCRs, in particular on those of invertebrates. In general, such receptors mediate the responses of signaling molecules that constitute the highest hierarchical position in the regulation of physiological processes. Until recently, only a few of these receptors were identified in invertebrates. However, the availability of a plethora of genomic information has boosted the discovery of novel members in several invertebrate species, such as Drosophila, in which 18 neuropeptide GPCRs have been characterized. The finalization of genomic projects in other invertebrates will lead to a similar expansion of GPCR understanding. Many new insights regarding neuropeptide regulation have followed from the discovery of their cognate receptors. Furthermore, information on GPCR signaling is still fragmentary and the elucidation of these pathways in model insects such as Drosophila will lead to further insights in other species, including mammals. In this review we present the current status of what is known about invertebrate GPCRs, discuss some novel perceptions that follow from the identified members, and, finally, present some future prospects.
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Affiliation(s)
- Tom Meeusen
- Laboratory of Developmental Physiology, Genomics, and Proteomics, K.U. Leuven, B-3000 Leuven, Belgium
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4
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Different roles of IP4
and IP3
in the signal pathway coupled to the TRH receptor in microinjected Xenopus
oocytes. FEBS Lett 2001. [DOI: 10.1016/0014-5793(89)80026-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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5
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The lymnaea cardioexcitatory peptide (LyCEP) receptor: a G-protein-coupled receptor for a novel member of the RFamide neuropeptide family. J Neurosci 1998. [PMID: 9822740 DOI: 10.1523/jneurosci.18-23-09812.1998] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel G-protein-coupled receptor (GRL106) resembling neuropeptide Y and tachykinin receptors was cloned from the mollusc Lymnaea stagnalis. Application of a peptide extract from the Lymnaea brain to Xenopus oocytes expressing GRL106 activated a calcium-dependent chloride channel. Using this response as a bioassay, we purified the ligand for GRL106, Lymnaea cardioexcitatory peptide (LyCEP), an RFamide-type decapeptide (TPHWRPQGRF-NH2) displaying significant similarity to the Achatina cardioexcitatory peptide (ACEP-1) as well as to the recently identified family of mammalian prolactin-releasing peptides. In the Lymnaea brain, the cells that produce egg-laying hormone are the predominant site of GRL106 gene expression and appear to be innervated by LyCEP-containing fibers. Indeed, LyCEP application transiently hyperpolarizes isolated egg-laying hormone cells. In the Lymnaea pericardium, LyCEP-containing fibers end blindly at the pericardial lumen, and the heart is stimulated by LyCEP in vitro. These data confirm that LyCEP is an RFamide ligand for GRL106.
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6
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Tensen CP, Cox KJ, Smit AB, van der Schors RC, Meyerhof W, Richter D, Planta RJ, Hermann PM, van Minnen J, Geraerts WP, Knol JC, Burke JF, Vreugdenhil E, van Heerikhuizen H. The lymnaea cardioexcitatory peptide (LyCEP) receptor: a G-protein-coupled receptor for a novel member of the RFamide neuropeptide family. J Neurosci 1998; 18:9812-21. [PMID: 9822740 PMCID: PMC6793288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
A novel G-protein-coupled receptor (GRL106) resembling neuropeptide Y and tachykinin receptors was cloned from the mollusc Lymnaea stagnalis. Application of a peptide extract from the Lymnaea brain to Xenopus oocytes expressing GRL106 activated a calcium-dependent chloride channel. Using this response as a bioassay, we purified the ligand for GRL106, Lymnaea cardioexcitatory peptide (LyCEP), an RFamide-type decapeptide (TPHWRPQGRF-NH2) displaying significant similarity to the Achatina cardioexcitatory peptide (ACEP-1) as well as to the recently identified family of mammalian prolactin-releasing peptides. In the Lymnaea brain, the cells that produce egg-laying hormone are the predominant site of GRL106 gene expression and appear to be innervated by LyCEP-containing fibers. Indeed, LyCEP application transiently hyperpolarizes isolated egg-laying hormone cells. In the Lymnaea pericardium, LyCEP-containing fibers end blindly at the pericardial lumen, and the heart is stimulated by LyCEP in vitro. These data confirm that LyCEP is an RFamide ligand for GRL106.
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Affiliation(s)
- C P Tensen
- Department of Biochemistry and Molecular Biology, Research Institute Neurosciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands
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7
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Akhundova A, Getmanova E, Gorbulev V, Carnazzi E, Eggena P, Fahrenholz F. Cloning and functional characterization of the amphibian mesotocin receptor, a member of the oxytocin/vasopressin receptor superfamily. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 237:759-67. [PMID: 8647123 DOI: 10.1111/j.1432-1033.1996.0759p.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Mesotocin is the oxytocin-like hormone found in most terrestrial vertebrates from lungfishes to marsupials, which includes all non-mammalian tetrapods (amphibians, reptiles, and birds). It has the largest distribution in vertebrates after vasotocin found in all non-mammalian vertebrates and isotocin identified in bony fishes. In this study, we report the cloning and functional characterization of the cDNA for the mesotocin receptor (MTR) from the urinary bladder of the toad Bufo marinus. The cloned cDNA encodes a polypeptide of 389 amino acids that shows the greatest similarity to the teleost fish isotocin receptor and to mammalian oxytocin receptors with mutations in extracellular loops which are involved in ligand binding. When expressed in COSM6 cells, MTR exhibits the following relative order of ligand affinity: mesotocin > vasotocin = oxytocin > vasopressin > hydrin 1, isotocin, hydrin 2. Injection of MTR cRNA into Xenopus laevis oocytes induces membrane chloride currents in response to mesotocin, which indicates the coupling of the mesotocin receptor to the inositol phosphate/calcium pathway. This response is inhibited by an oxytocin antagonist, but not by a vasopressin antagonist specific for V2 vasopressin receptors. MTR mRNA is not only found in toad urinary bladder, but also in kidney, muscle, and brain tissue of the toad as revealed by northern blot analysis and reverse-transcriptase PCR. The results suggest a variety of function for mesotocin and its receptor including, in particular, an involvement in the regulation of water and salt transport.
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Affiliation(s)
- A Akhundova
- Max-Planck-Institute of Biophysics, Frankfurt am Main, Germany
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8
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van Kesteren RE, Tensen CP, Smit AB, van Minnen J, Kolakowski LF, Meyerhof W, Richter D, van Heerikhuizen H, Vreugdenhil E, Geraerts WP. Co-evolution of ligand-receptor pairs in the vasopressin/oxytocin superfamily of bioactive peptides. J Biol Chem 1996; 271:3619-26. [PMID: 8631971 DOI: 10.1074/jbc.271.7.3619] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
In order to understand the molecular mechanisms that underlie the co-evolution of related yet functionally distinct peptide-receptor pairs, we study receptors for the vasopressin-related peptide Lys-conopressin in the mollusc Lymnaea stagnalis. In addition to a previously cloned Lys-conopressin receptor (LSCPR1), we have now identified a novel Lys-conopressin receptor subtype, named LSCPR2. The two receptors have a differential distribution in the reproductive organs and the brain, which suggests that they are involved in the control of distinct aspects of reproduction and mediate transmitter-like and/or modulatory effects of Lys-conopressin on different types of central neurons. In contrast to LSCPR1, LSCPR2 is maximally activated by both Lys-conopressin and Ile-conopressin, an oxytocin-like synthetic analog of Lys-conopressin. Together with a study of the phylogenetic relationships of Lys-conopressin receptors and their vertebrate counterparts, these data suggest that LSCPR2 represents an ancestral receptor to the vasopressin/oxytocin receptor family in the vertebrates. Based on our findings, we provide a theory of the molecular co-evolution of the functionally distinct ligand-receptor pairs of the vasopressin/oxytocin superfamily of bioactive peptides.
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Affiliation(s)
- R E van Kesteren
- Department of Experimental Zoology, Graduate School of Neurosciences Amsterdam, Institute of Neuroscience, Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands
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9
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Affiliation(s)
- S J Lolait
- Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, Maryland 20892, USA
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10
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Mohr E, Meyerhof W, Richter D. Vasopressin and oxytocin: molecular biology and evolution of the peptide hormones and their receptors. VITAMINS AND HORMONES 1995; 51:235-66. [PMID: 7483323 DOI: 10.1016/s0083-6729(08)61040-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- E Mohr
- Institut für Zellbiochemie und Klinische Neurobiologie, Universität Hamburg, Germany
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11
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Mahlmann S, Meyerhof W, Hausmann H, Heierhorst J, Schönrock C, Zwiers H, Lederis K, Richter D. Structure, function, and phylogeny of [Arg8]vasotocin receptors from teleost fish and toad. Proc Natl Acad Sci U S A 1994; 91:1342-5. [PMID: 7509069 PMCID: PMC43154 DOI: 10.1073/pnas.91.4.1342] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
[Arg8]Vasotocin (AVT) is considered to be the most primitive known vertebrate neurohypophyseal peptide of the vasopressin/oxytocin hormone family and may thus be ancestral to all the other vertebrate peptide hormones. The molecular evolution of the corresponding receptor family has now been studied by cloning an AVT receptor, consisting of 435 amino acid residues, from the teleost fish, the white sucker Catostomus commersoni. Frog oocytes injected with the AVT receptor-encoding cRNA respond to the application of AVT, but not to its structural and functional counterpart isotocin, by an induction of membrane chloride currents indicating the coupling of the AVT receptor to the inositol phosphate/calcium pathway. The pharmacological properties of the expressed AVT receptor show that it represents, or is closely related to, an ancestral nonapeptide receptor: oxytocin, aspargtocin, mesotocin, and vasopressin activated the receptor, but other members of the vasopressin/oxytocin family tested showed little or no potency; antagonists of the mammalian vasopressin V1 and oxytocin receptors blocked the AVT response. Comparison of AVT receptor sequences spanning transmembrane domains two to five, deduced by cloning cDNAs from the Pacific salmon Oncorhynchus kisutch, the cave-dwelling fish Astyanax fasciatus, and the anuran Xenopus laevis, with those of their mammalian counterparts emphasizes amino acid residues that are involved in hormone binding. The presence of a 5.0-kb transcript in various teleost tissues (pituitary, liver, gills, swim bladder, and lateral line) points to a physiological role for the fish AVT receptor in metabolic, osmoregulatory, and sensory processes.
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Affiliation(s)
- S Mahlmann
- Institut für Zellbiochemie und klinische Neurobiologie, Universität Hamburg, Germany
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12
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Gershengorn MC. Thyrotropin-releasing hormone receptor: cloning and regulation of its expression. RECENT PROGRESS IN HORMONE RESEARCH 1993; 48:341-63. [PMID: 8382829 DOI: 10.1016/b978-0-12-571148-7.50016-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- M C Gershengorn
- Department of Medicine, Cornell University Medical College, New York, New York
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13
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de la Peña P, Delgado LM, del Camino D, Barros F. Cloning and expression of the thyrotropin-releasing hormone receptor from GH3 rat anterior pituitary cells. Biochem J 1992; 284 ( Pt 3):891-9. [PMID: 1377915 PMCID: PMC1132623 DOI: 10.1042/bj2840891] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Functional thyrotropin-releasing hormone (TRH) receptors have been expressed in Xenopus laevis oocytes following the microinjection of total and poly(A)+ RNA from GH3 rat anterior pituitary tumour cells. Under voltage-clamp conditions, application of the peptide induced a biphasic Ca(2+)-dependent chloride current. The amplitude of the initial, fast, component of the response was dependent on the concentration of the hormone and on the amount of mRNA injected. Size fractionation of poly(A)+ RNA on a continuous sucrose gradient and Northern blot analysis indicated that the receptor was encoded by an mRNA of approx. 3.5 kb. A 3.28 kbp cDNA encoding the TRH receptor has been cloned and sequenced. Full functionality of the predicted 412-amino-acid receptor protein was demonstrated by functional expression of cell surface receptors in Xenopus oocytes after both cytoplasmic injection of sense RNA transcribed in vitro from this cDNA and nuclear injection of the cDNA under the control of the Herpes simplex virus thymidine kinase promoter. The predicted protein contains seven putative membrane-spanning domains and shows significant sequence identify with some G-protein-coupled receptors. RNA blot analysis indicates that the mRNA for the TRH receptor is exclusively expressed in the pituitary gland. Expression studies performed with clones in which the 3' region of the mRNA has been successively shortened indicate that the 3' terminal region is not an important determinant for efficient functional expression in oocytes.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Blotting, Northern
- Cell Line
- Cloning, Molecular/methods
- DNA, Neoplasm/genetics
- Gene Library
- Mice
- Molecular Sequence Data
- Oocytes/drug effects
- Oocytes/physiology
- Pituitary Gland, Anterior
- Pituitary Neoplasms
- Poly A/genetics
- Poly A/isolation & purification
- RNA/genetics
- RNA/isolation & purification
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/isolation & purification
- Rats
- Receptors, Neurotransmitter/drug effects
- Receptors, Neurotransmitter/genetics
- Receptors, Neurotransmitter/physiology
- Receptors, Serotonin/drug effects
- Receptors, Serotonin/genetics
- Receptors, Serotonin/physiology
- Receptors, Thyrotropin-Releasing Hormone
- Recombinant Proteins/drug effects
- Recombinant Proteins/metabolism
- Sequence Homology, Nucleic Acid
- Serotonin/pharmacology
- Thyrotropin-Releasing Hormone/metabolism
- Thyrotropin-Releasing Hormone/pharmacology
- Transcription, Genetic
- Xenopus laevis
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Affiliation(s)
- P de la Peña
- Departamento de Biología Funcional, Facultad de Medicina, Universidad de Oviedo, Spain
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14
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Cantau B, Bartolami S, Baskevitch PP, Desarnaud F, Chicot D, Jard S. Angiotensin receptors from rat liver, brain and pituitary gland. Expression of two subtypes in Xenopus oocytes. Biochem J 1991; 277 ( Pt 3):729-33. [PMID: 1872809 PMCID: PMC1151305 DOI: 10.1042/bj2770729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Xenopus laevis oocytes were used to express angiotensin receptors encoded by mRNAs extracted from rat liver, adenohypophysis and brain. Groups of ten mRNA-injected oocytes were loaded with 45Ca2+ and the responsiveness to angiotensin II (A II) and related molecules tested by monitoring 45Ca2+ outflux. A II and angiotensin III (A III) induced a marked and transient increase in 45Ca2+ outflux from mRNA, but not from control, water-injected, oocytes. The increase over basal value of 45Ca2+ outflux during a 5 min application period of A II or A III was used as a response index. Observed responses were of high magnitude, reproducible and dose-dependent. For these reasons, mRNA-injected oocytes constitute a valuable system for investigating the pharmacological properties of angiotensin receptors from tissues of different origin under experimental conditions which eliminate tissue-specific interference which might be encountered in classical binding studies on acellular preparations. We demonstrate a fairly good parallelism between the relative potencies of A I, A II and A III in eliciting an increase in 45Ca2+ outflux from liver and adenohypophyseal mRNA-injected oocytes and the relative affinities of these peptides for binding to liver or adenohypophyseal membranes (A II greater than A III much greater than A I). The predominant receptor subtype expressed by brain mRNA discriminated very poorly between A II and A III, whereas angiotensin receptors expressed by liver or adenohypophyseal mRNA discriminated between AII and AIII very efficiently.
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Affiliation(s)
- B Cantau
- Centre CNRS-INSERM de Pharmacologie-Endocrinologie, Montpellier, France
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15
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Abstract
Electrical recordings were used to study the sensitivity of native Xenopus oocytes to the octapeptide angiotensin II (AII). AII elicited oscillatory currents associated with an increase in membrane conductance to Cl-. Responsiveness to AII varied greatly between oocytes taken from different frogs, and to a lesser extent between oocytes from the same ovary. Oocytes from frogs showing high sensitivity had response thresholds between 0.5-1.0 nM AII, and at a holding potential of -60 mV, responded to 1 microM AII with currents greater than 3 microA. In contrast, oocytes from some frogs gave no response, even to 10 microM AII. A total of 618 oocytes from 79 frogs were tested for sensitivity to AII, and oocytes from 85% of frogs gave detectable electrical responses. Oscillatory Cl- currents elicited by AII were largely independent of extracellular Ca2+, were abolished by chelation of intracellular Ca2+ using EGTA and were mimicked by intraoocyte injection of inositol 1,4,5-trisphosphate (IP3). In addition to oscillatory Cl- currents, AII also evoked an influx of extracellular Ca2+, giving rise to a transient inward Cl- current on membrane hyperpolarizing steps. These experiments all suggested that AII responses were elicited through activation of an intracellular messenger pathway triggered by hydrolysis of inositolphospholipids, mobilization of intracellular Ca2+ by inositol polyphosphates, and activation of Ca(2+)-gated Cl- channels. The effect of manual or enzymic defolliculation on AII responses was studied in nine separate experiments recording from 70 defolliculated oocytes. Efficacy of defolliculation procedures was assayed using scanning electron microscopy, which confirmed removal of 90 to greater than 98% of follicular cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R M Woodward
- Department of Psychobiology, University of California, Irvine 92717
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16
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Fluharty SJ, Reagan LP, White MM. Endogenous and expressed angiotensin II receptors on Xenopus oocytes. J Neurochem 1991; 56:1307-11. [PMID: 2002343 DOI: 10.1111/j.1471-4159.1991.tb11426.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Intact Xenopus oocytes contain a homogeneous population of binding sites for the angiotensin II (Ang II) receptor antagonist 125I-[Sarc1,Ile8]-Ang II (125I-SARILE). Binding of 125I-SARILE to intact oocytes was saturable and of high affinity with an apparent KD of 0.7 nM and maximal density of 0.12 fmol/oocyte. Binding of 125I-SARILE to oocytes also was specific for Ang II-related peptides with a rank order potency of: [Sarc1]-Ang II greater than Ang II greater than Ang III much greater than Ang I. However, these endogenous binding sites were present only in follicle-enclosed oocytes and within the follicular layer itself. On the other hand, injection of poly(A)+ RNA isolated from murine N1E-115 neuroblastoma cells into oocytes resulted in the appearance of 125I-SARILE binding sites even in defolliculated oocytes. These expressed receptors exhibited pharmacological properties similar to those endogenously present in the follicular layer, although their levels were much less. Collectively, these results suggest that endogenous Ang II receptors are present on Xenopus oocyte follicle cells, whereas Ang II receptors expressed from exogenous N1E-115 RNA are found on the oocytes themselves. In addition, the high density of Ang II receptors on the follicle cells emphasizes the necessity for care in using Xenopus oocytes for the expression of receptors encoded by exogenous RNAs.
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Affiliation(s)
- S J Fluharty
- Department of Animal Biology, School of Medicine, University of Pennsylvania, Philadelphia 19104
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17
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Richter D, Meyerhof W, Buck F, Morley SD. Molecular biology of receptors for neuropeptide hormones. CURRENT TOPICS IN PATHOLOGY. ERGEBNISSE DER PATHOLOGIE 1991; 83:117-39. [PMID: 1848802 DOI: 10.1007/978-3-642-75515-6_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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18
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Richter D, Morley SD, Buck F, Meyerhof W. Neuropeptide hormone receptors: strategies for identification. JOURNAL OF RECEPTOR RESEARCH 1991; 11:483-505. [PMID: 1653349 DOI: 10.3109/10799899109066423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Study of the structure--function relationship of neuropeptide hormone receptors presents a number of technical difficulties associated with the isolation of a given receptor protein in a purified form. A variety of molecular approaches has enabled corresponding cDNA clones to be isolated without the need to embark on protein purification procedures. However, the molecular cloning approach requires that appropriate tools for identifying cDNAs encoding the respective receptor be available. Strategies designed to address this problem will be discussed and include functional expression of neuropeptide hormone receptors in frog oocytes, hybrid depletion and inactivation of receptor-encoding mRNAs by RNase H digestion, polymerase chain reaction (PCR) amplification of cDNAs encoding putative receptors, and expression of transfected receptor genes in cell cultures followed by identification using a cell sorter.
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Affiliation(s)
- D Richter
- Institut für Zellbiochemie und klinische Neurobiologie, UKE, Universität Hamburg, FRG
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19
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Sigel E. Use of Xenopus oocytes for the functional expression of plasma membrane proteins. J Membr Biol 1990; 117:201-21. [PMID: 2231695 DOI: 10.1007/bf01868451] [Citation(s) in RCA: 127] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- E Sigel
- Pharmakologisches Institut, Universität Bern, Switzerland
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20
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Wright MS, Karlsen HE, Paulssen EJ, Meyerhof W, Høgset A, Gautvik KM. Different-sized mRNAs from GH4C1 cells induce a TRH-dependent electrical response in Xenopus laevis oocytes. ACTA PHYSIOLOGICA SCANDINAVICA 1990; 140:129-34. [PMID: 2177312 DOI: 10.1111/j.1748-1716.1990.tb08983.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Poly(A)+ RNA from the GH4C1 rat pituitary cell line elicited a thyrotropin releasing hormone response in Xenopus laevis oocytes which could be measured as a change in membrane current by the voltage-clamp method. Oocytes injected with Poly(A)+ RNA from GH12C1 cells which do not bind thyrotropin releasing hormone or with buffer solution alone did not show this response. Size fractionation of total poly(A)+ RNA by sucrose density-gradient centrifugation shows two response maximal representing various mRNA fractions larger than 18S. These results indicate the presence of thyrotropin releasing hormone receptor mRNA heterogeneity where the smallest mRNA is at least 2 kb.
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Affiliation(s)
- M S Wright
- Institute of Medical Biochemistry, University of Oslo, Norway
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21
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Meyerhof W, Schwärzt JR, Höllt V, Richter D. Expression of Histamine HReceptors in Xenopus Oocytes Injected with Messenger Ribonucleic Acid from Bovine Adrenal Medulla: Pertussis Toxin Insensitive Activation of Membrane Chloride Currents. J Neuroendocrinol 1990; 2:547-53. [PMID: 19215387 DOI: 10.1111/j.1365-2826.1990.tb00446.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Abstract Histamine H(2)-receptors have been identified in Xenopus oocytes previously microinjected with poly(A) + ribonucleic acid from bovine adrenal glands. Bath application of histamine to ribonucleic acid-primed oocytes evoked concentration-dependent, oscillating membrane currents under voltage-clamp conditions. H(1)-receptor specific antagonists clemastine, doxepin, pyrilamine, promethacine, diphenylhydramine, dephenylpyraline and chlorpheniramine, but not H(2)-receptor antagonists, cimetidine and ranitidine, inhibited histamine-induced responses. Membrane currents evoked by bath-applied histamine were insensitive to pertussis toxin, carried by chloride ions and dependent on intracellular but not extracellular calcium.
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Affiliation(s)
- W Meyerhof
- Institut für Zellbiochemie und klinische Neurobiologie, Universität Hamburg, UKE, Martinistr. 52, D-2000 Hamburg 20, FRG
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Sandberg K, Bor M, Ji H, Markwick A, Millan MA, Catt KJ. Angiotensin II-induced calcium mobilization in oocytes by signal transfer through gap junctions. Science 1990; 249:298-301. [PMID: 2374929 DOI: 10.1126/science.2374929] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Angiotensin II (AII) stimulates rapid increases in the concentration of cytosolic calcium in follicular oocytes from Xenopus laevis. This calcium response was not present in denuded oocytes, indicating that it is mediated by AII receptors on the adherent follicular cells. The endogenous AII receptors differed in their binding properties from mammalian AII receptors expressed on the oocyte surface after injection of rat adrenal messenger RNA. Also, the calcium responses to activation of the amphibian AII receptor, but not the expressed mammalian AII receptor, were blocked reversibly by octanol and intracellular acidification, treatments that inhibit cell coupling through gap junctions. In addition, AII increased the rate of progesterone-induced maturation. Thus, an AII-induced calcium-mobilizing signal is transferred from follicle cells to the oocyte through gap junctions and may play a physiological role in oocyte maturation.
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Affiliation(s)
- K Sandberg
- Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
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23
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Meyerhof W, Richter D. Identification of G protein-coupled receptors by RNase H-mediated hybrid depletion using Xenopus laevis oocytes as expression system. FEBS Lett 1990; 266:192-4. [PMID: 1694786 DOI: 10.1016/0014-5793(90)81537-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A method has been developed for rapidly identifying putative G protein-coupled receptors isolated initially as small cDNA fragments, following reverse transcription and polymerase chain reaction (PCR) amplification of mRNA. The method is based upon the use of synthetic oligonucleotides deduced from the sequence of the amplified receptor fragments, to direct a RNase H-mediated specific degradation of hybrids formed between the oligonucleotides and the corresponding receptor-encoding mRNA. Loss of an agonist-dependent receptor response in the Xenopus laevis oocyte expression system identifies the amplified receptor fragment. Taking in vitro synthesised serotonin HT2-receptor (SR)-encoding mRNA as a model, it was shown that following incubation with RNase H and SR antisense oligonucleotides, injection of this message no longer caused the acquisition of agonist-dependent membrane currents in voltage-clamped oocytes. In contrast, when corresponding sense oligonucleotides were used, the serotonin-evoked membrane responses in oocytes were acquired as normal. The method should allow the identification of receptors which can functionally be expressed and measured in Xenopus oocytes.
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Affiliation(s)
- W Meyerhof
- Institut für Zellbiochemie und klinische Neurobiologie, UKE, Universität Hamburg, FRG
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Ross PC, Figler RA, Corjay MH, Barber CM, Adam N, Harcus DR, Lynch KR. RTA, a candidate G protein-coupled receptor: cloning, sequencing, and tissue distribution. Proc Natl Acad Sci U S A 1990; 87:3052-6. [PMID: 2109324 PMCID: PMC53832 DOI: 10.1073/pnas.87.8.3052] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Genomic and cDNA clones, encoding a protein that is a member of the guanine nucleotide-binding regulatory protein (G protein)-coupled receptor superfamily, were isolated by screening rat genomic and thoracic aorta cDNA libraries with an oligonucleotide encoding a highly conserved region of the M1 muscarinic acetylcholine receptor. Sequence analyses of these clones showed that they encode a 343-amino acid protein (named RTA). The RTA gene is single copy, as demonstrated by restriction mapping and Southern blotting of genomic clones and rat genomic DNA. Sequence analysis of the genomic clone further showed that the RTA gene has an intron interrupting the region encoding the amino terminus of the protein. RTA RNA sequences are relatively abundant throughout the gut, vas deferens, uterus, and aorta but are only barely detectable (on Northern blots) in liver, kidney, lung, and salivary gland. In the rat brain, RTA sequences are markedly abundant in the cerebellum. RTA is most closely related to the mas oncogene (34% identity), which has been suggested to be a forebrain angiotensin receptor. We cannot detect angiotensin binding to the RTA protein after introducing the cognate cDNA or mRNA into COS cells or Xenopus oocytes, respectively, nor can we detect an electrophysiologic response in the oocyte after application of angiotensin peptides. We conclude that RTA is not an angiotensin receptor; to date, we have been unable to identify its ligand.
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Affiliation(s)
- P C Ross
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville 22908
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25
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Gershengorn MC, Oron Y, Straub RE. Xenopus laevis oocytes injected with mammalian pituitary mRNA as a model system for study of thyrotropin-releasing hormone action. THE JOURNAL OF EXPERIMENTAL ZOOLOGY. SUPPLEMENT : PUBLISHED UNDER AUSPICES OF THE AMERICAN SOCIETY OF ZOOLOGISTS AND THE DIVISION OF COMPARATIVE PHYSIOLOGY AND BIOCHEMISTRY 1990; 4:78-83. [PMID: 1974807 DOI: 10.1002/jez.1402560414] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- M C Gershengorn
- Department of Medicine, Cornell University Medical College, New York, New York
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Stifani S, Nimpf J, Schneider WJ. Vitellogenesis in Xenopus laevis and chicken: cognate ligands and oocyte receptors. The binding site for vitellogenin is located on lipovitellin I. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)40132-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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27
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Abstract
1. Membrane currents were recorded from voltage-clamped Xenopus oocytes in response to bath application of various divalent cations. 2. In oocytes from 93 of 160 frogs tested, Co2+ ions evoked slow, oscillatory membrane currents. Sensitivity to Co2+ varied greatly between oocytes from different frogs, but was relatively consistent for oocytes taken from the same ovary. Oocytes with high sensitivity had response thresholds of 5-10 microM, and gave currents greater than 1 microA to 1 mM-CoCl2. In contrast, oocytes from some frogs gave no oscillatory response even to 10 mM-CoCl2. With responsive oocytes, Cd2+, Ni2+, Zn2+, Mn2+ and Cr2+ ions (5 microM to 1 mM) also elicited oscillations, whereas Sr2+, Ba2+ and Ca2+ (0.1-10 mM) showed very little activity, and Mg2+ ions, none. 3. Responses to divalent cation were well preserved in defolliculated oocytes, indicating they were generated in the oocyte membrane itself, and were not dependent on the presence of enveloping follicular cells. 4. The oscillatory currents reversed around -20 mV (the chloride equilibrium potential) and rectified strongly at potentials more negative than about -60 mV. The oscillations were mimicked by intraoocyte injection of inositol 1,4,5-trisphosphate (IP3), were largely preserved after removal of external Ca2+, but were abolished following chelation of intracellular Ca2+ by EGTA. Intraoocyte injection of Co2+ ions failed to generate oscillatory currents. 5. Currents elicited by divalent cations resembled the oocyte's oscillatory responses to acetylcholine and a serum protein. However, the response to divalent cations was not blocked by atropine and furthermore, the relative sensitivities to these agonists varied independently between oocytes from different frogs. 6. We conclude that extracellular Cd2+, Ni2+, Zn2+, Co2+, Mn2+ and Cr2+ interact with the oocyte surface to raise cytosolic levels of inositol phosphates. This causes mobilization of intracellular Ca2+, in turn activating Ca2+-gated Cl- channels in the oocyte membrane. 7. In addition to the large oscillatory currents, divalent cations generated small (5-50 nA), smooth, maintained currents associated with decreases in membrane conductance. The size and ionic basis of these currents varied between oocytes from different frogs. 8. Zinc ions also elicited smooth currents, associated with an increase in membrane conductance, and carried predominantly by K+. This response was specific to Zn2+ and occurred independently of oscillatory Cl- currents. The K+ current was abolished by defolliculation, was potentiated by the cyclic AMP phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine,and showed facilitation with K+ currents generated by the adenylate cyclase activator forskolin.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- R Miledi
- Department of Psychobiology, University of California, Irvine 92717
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Abstract
1. Catecholamines, adenosine, gonadotrophins, vasoactive intestinal peptide (VIP) and E-series prostaglandins all elicit K+ currents in follicle-enclosed Xenopus oocytes. Evidence suggests that cyclic nucleotides act as intracellular messengers in the activation of this K+ conductance. Muscarinic agonists and some divalent cations (e.g. Co2+, Mn2+, Ni2+ and Cd2+) elicit slow oscillatory Cl- currents, which are activated through hydrolysis of inositol phospholipids and mobilization of intracellular calcium by inositol phosphates. 2. We investigated whether these membrane current responses were generated in the oocyte itself or in enveloping follicular cells which are coupled to the oocyte by gap junctions. Oocytes were defolliculated, either enzymatically using collagenase, or by manual dissection combined with rolling over poly-L-lysine-coated slides. Removal of follicular cells was checked using scanning electron microscopy. Membrane current responses of defolliculated oocytes were compared with responses seen in follicle-enclosed oocytes taken from the same ovary. 3. The K+ responses evoked by all the various hormones/neurotransmitters were either drastically reduced (greater than 90%) or abolished by defolliculation. K+ currents generated by the adenylate cyclase activator forskolin and by intraoocyte injection of adenosine 3',5'-cyclic monophosphate (cyclic AMP), or guanosine 3',5'-cyclic monophosphate were similarly reduced in defolliculated oocytes. In contrast, oscillatory Cl- currents to acetylcholine and divalent cations were selectively preserved through defolliculation. 4. Injection of cyclic AMP (1-20 pmol) into defolliculated oocytes had little or no effect on oscillatory Cl- currents elicited by ACh. However, the calcium-dependent transient Cl- current, activated by depolarization of the oocyte membrane, was consistently potentiated (100-900%) by injections of cyclic AMP (1-10 pmol). 5. These experiments suggest that cyclic nucleotide-activated K+ currents arise essentially in follicular cells and are monitored within the oocyte through electrical coupling by gap junctions. Oscillatory Cl- responses evoked by ACh and divalent cations are produced largely or wholly in the oocyte itself.
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Affiliation(s)
- R Miledi
- Department of Psychobiology, University of California, Irvine 92717
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Coupling of exogenous receptors to phospholipase C in Xenopus oocytes through pertussis toxin-sensitive and -insensitive pathways. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)80028-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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30
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Meyerhof W, Richter D. Characterization of neuropeptide-induced membrane chloride currents in Xenopus oocytes primed with exogenous mRNA. JOURNAL OF PROTEIN CHEMISTRY 1989; 8:365-8. [PMID: 2477014 DOI: 10.1007/bf01674281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- W Meyerhof
- Institut für Zellbiochemie und Klinische Neurobiologie, Universitäts-Krankenhaus Eppendorf, Hamburg, FRG
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31
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Olate J, Jorquera H, Purcell P, Codina J, Birnbaumer L, Allende JE. Molecular cloning and sequence determination of a cDNA coding for the alpha-subunit of a Go-type protein of Xenopus laevis oocytes. FEBS Lett 1989; 244:188-92. [PMID: 2494063 DOI: 10.1016/0014-5793(89)81190-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Xenopus laevis oocytes are cells ideally suited to the study of signal transduction and of the G-proteins that are involved in this process. A X. laevis cDNA library in lambda gt10 has been screened with a mixture of three oligonucleotide probes designed to detect sequences found in various mammalian alpha-subunits of G-proteins. One of these clones has been purified through tertiary screening and the DNA insert has been sequenced. This clone was found to include the total sequence coding for a 354 amino acid protein that is 89% identical to the sequence of alpha-subunit of rat Go. The differences with the mammalian protein were clustered in amino acids 290-315, which have been postulated to define the region interacting with the receptor and effector molecule. The homology with the alpha-subunits of other mammalian G-proteins is lower (65-70% to Gi and 42% to Gs). On this basis, this clone can be classified as Go-like.
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Affiliation(s)
- J Olate
- Departamento de Bioquímica, Facultad de Medicina, Universidad de Chile, Santiago
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Mahlmann S, Schwarz JR, Meyerhof W. Modulation of Neuropeptide-lnduced Membrane Currents by Protein Kinase C in Xenopus Oocytes Injected with GH Pituitary Cell Poly(A) RNA. J Neuroendocrinol 1989; 1:65-9. [PMID: 19210484 DOI: 10.1111/j.1365-2826.1989.tb00078.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Abstract Protein kinase C was activated in Xenopus laevis oocytes by phorbol ester treatment and its effects on the inositol trisphosphate/Ca(2+) transmembrane signalling pathway analysed. Induction of the pathway was achieved by ligand stimulation of TRH receptors translated from GH(3) pituitary cell mRNA. In voltage-clamped oocytes bath application of peptide, injection of guanosine 5'-(3-O-thio) triphosphate (GTPgammaS), inositol trisphosphate or Ca(2+) all elicited inward membrane currents. Treatment of oocytes with tumour-promoting phorbol esters for 35 min almost completely abolished the ligand and GTPgammaS-induced responses. In contrast, phorbol ester treatment enhanced inositol trisphosphate-generated membrane currents. Ca(2+)-mediated responses remained unaffected by tumour promoters. The data indicate a dual role for protein kinase C in the modulation of transmembrane signalling: a feedback mechanism prevents phosphoinositide turnover whereas a feedforward reaction triggers the effect of intracellular inositol trisphosphate on the Ca(2+) release.
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Affiliation(s)
- S Mahlmann
- Physiologisches Institut, Universitats-Krankenhaus Eppendorf, Martinistr. 52, D-2000 Hamburg 20, FRG
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Sandberg K, Markwick AJ, Trinh DP, Catt KJ. Calcium mobilization by angiotensin II and neurotransmitter receptors expressed in Xenopus laevis oocytes. FEBS Lett 1988; 241:177-80. [PMID: 2848720 DOI: 10.1016/0014-5793(88)81055-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Specific receptors for angiotensin II (AII) were expressed in albino Xenopus laevis oocytes co-injected with poly(A)+ mRNA isolated from rat adrenal cortex and the calcium-specific photoprotein, aequorin. In such oocytes, AII elicited rapid, dose-dependent rises in cytosolic free calcium with light emission responses up to 100-fold above basal levels. Ligand-induced light emission was also observed in oocytes injected with rat brain mRNA and stimulated with acetylcholine and glutamate. These findings demonstrate that mammalian AII receptors expressed in Xenopus oocytes are functionally linked to intracellular Ca2+ mobilization, and indicate the potential value of aequorin-injected oocytes for rapid and specific screening of mRNAs transcribed from expression libraries containing cloned receptor cDNAs.
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Affiliation(s)
- K Sandberg
- Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, Bethesda, MD 20892
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Meyerhof W, Morley SD, Richter D. Expression and electrophysiological identification of the receptor for bombesin and gastrin-releasing peptide in Xenopus laevis oocytes injected with polyA+ RNA from rat brain. FEBS Lett 1988; 239:109-12. [PMID: 2460369 DOI: 10.1016/0014-5793(88)80555-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The receptor for bombesin and the related peptide, gastrin-releasing peptide (GRP) has been induced in frog oocytes by injection of polyA+ RNA from rat brain. The primed oocytes responded to peptides of the bombesin family (GRP, neuromedin C of bombesin) by showing dose-dependent oscillations in membrane currents as recorded by the voltage-clamp method. The induced membrane changes were suppressed when oocytes were pretreated with a bombesin-receptor antagonist.
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Affiliation(s)
- W Meyerhof
- Institut für Zellbiochemie und klinische Neurobiologie, Universitäts-Krankenhaus Eppendorf, Hamburg, FRG
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Kumar CS, Mariano TM, Noe M, Deshpande AK, Rose PM, Pestka S. Expression of the murine interferon gamma receptor in Xenopus laevis oocytes. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)68266-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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