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Seifert R. Is cIMP a second messenger with functions opposite to those of cGMP? Naunyn Schmiedebergs Arch Pharmacol 2014; 387:897-9. [PMID: 25017018 DOI: 10.1007/s00210-014-1013-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 06/18/2014] [Indexed: 12/21/2022]
Affiliation(s)
- Roland Seifert
- Institute of Pharmacology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany,
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2
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Köse M, Ritter K, Thiemke K, Gillard M, Kostenis E, Müller CE. Development of [(3)H]2-Carboxy-4,6-dichloro-1H-indole-3-propionic Acid ([(3)H]PSB-12150): A Useful Tool for Studying GPR17. ACS Med Chem Lett 2014; 5:326-30. [PMID: 24900835 DOI: 10.1021/ml400399f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 01/16/2014] [Indexed: 11/29/2022] Open
Abstract
The recently described synthetic GPR17 agonist 2-carboxy-4,6-dichloro-1H-indole-3-propionic acid (1) was prepared in tritium-labeled form by catalytic hydrogenation of the corresponding propenoic acid derivative 8 with tritium gas. The radioligand [(3)H]PSB-12150 (9) was obtained with a specific activity of 17 Ci/mmol (629 GBq/mmol). It showed specific and saturable binding to a single binding site in membrane preparations from Chinese hamster ovary cells recombinantly expressing the human GPR17. A competition assay procedure was established, which allows the determination of ligand binding affinities.
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Affiliation(s)
- Meryem Köse
- PharmaCenter
Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, Bonn, Germany
| | - Kirsten Ritter
- PharmaCenter
Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, Bonn, Germany
| | - Katharina Thiemke
- PharmaCenter
Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, Bonn, Germany
| | - Michel Gillard
- UCB Pharma S.A., CNS Research, Chemin du Foriest, B-1420 Braine-l’Alleud, Belgium
| | - Evi Kostenis
- PharmaCenter
Bonn, Institute of Pharmaceutical Biology, Section of Molecular-,
Cellular-, and Pharmacobiology, University of Bonn, Bonn, Germany
| | - Christa E. Müller
- PharmaCenter
Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, Bonn, Germany
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Knospe M, Müller CE, Rosa P, Abdelrahman A, von Kügelgen I, Thimm D, Schiedel AC. The rat adenine receptor: pharmacological characterization and mutagenesis studies to investigate its putative ligand binding site. Purinergic Signal 2013; 9:367-81. [PMID: 23413038 PMCID: PMC3757150 DOI: 10.1007/s11302-013-9355-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Accepted: 01/23/2013] [Indexed: 12/20/2022] Open
Abstract
The rat adenine receptor (rAdeR) was the first member of a family of G protein-coupled receptors (GPCRs) activated by adenine and designated as P0-purine receptors. The present study aimed at gaining insights into structural aspects of ligand binding and function of the rAdeR. We exchanged amino acid residues predicted to be involved in ligand binding (Phe110(3.24), Asn115(3.29), Asn173(4.60), Phe179(45.39), Asn194(5.40), Phe195(5.41), Leu201(5.47), His252(6.54), and Tyr268(7.32)) for alanine and expressed them in Spodoptera frugiperda (Sf9) insect cells. Membrane preparations subjected to [(3)H]adenine binding studies revealed only minor effects indicating that none of the exchanged amino acids is part of the ligand binding pocket, at least in the inactive state of the receptor. Furthermore, we coexpressed the rAdeR and its mutants with mammalian Gi proteins in Sf9 insect cells to probe receptor activation. Two amino acid residues, Asn194(5.40) and Leu201(5.47), were found to be crucial for activation since their alanine mutants did not respond to adenine. Moreover we showed that-in contrast to most other rhodopsin-like GPCRs-the rAdeR does not contain essential disulfide bonds since preincubation with dithiothreitol neither altered adenine binding in Sf9 cell membranes, nor adenine-induced inhibition of adenylate cyclase in 1321N1 astrocytoma cells transfected with the rAdeR. To detect rAdeRs by Western blot analysis, we developed a specific antibody. Finally, we were able to show that the extended N-terminal sequence of the rAdeR constitutes a putative signal peptide of unknown function that is cleaved off in the mature receptor. Our results provide important insights into this new, poorly investigated family of purinergic receptors.
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Affiliation(s)
- Melanie Knospe
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Christa E. Müller
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Patrizia Rosa
- />CNR—Institute of Neuroscience and Department of Medical Biotechnologies and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Aliaa Abdelrahman
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Ivar von Kügelgen
- />PharmaCenter Bonn, Department of Pharmacology, University of Bonn, Sigmund-Freud-Straße 25, 53127 Bonn, Germany
| | - Dominik Thimm
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Anke C. Schiedel
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
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Thimm D, Knospe M, Abdelrahman A, Moutinho M, Alsdorf BBA, von Kügelgen I, Schiedel AC, Müller CE. Characterization of new G protein-coupled adenine receptors in mouse and hamster. Purinergic Signal 2013; 9:415-26. [PMID: 23608776 PMCID: PMC3757137 DOI: 10.1007/s11302-013-9360-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/26/2013] [Indexed: 10/26/2022] Open
Abstract
The nucleobase adenine has previously been reported to activate G protein-coupled receptors in rat and mouse. Adenine receptors (AdeR) thus constitute a new family of purine receptors, for which the designation "P0-receptors" has been suggested. We now describe the cloning and characterization of two new members of the AdeR family from mouse (MrgA10, termed mAde1R) and hamster (cAdeR). Both receptors were expressed in Sf9 insect cells, and radioligand binding studies were performed using [(3)H]adenine. Specific binding of the radioligand was detected in transfected, but not in untransfected cells, and K D values of 286 nM (mAde1R, B max 1.18 pmol/mg protein) and 301 nM (cAdeR, B max 17.7 pmol/mg protein), respectively, were determined. A series of adenine derivatives was investigated in competition binding assays. Minor structural modifications generally led to a reduction or loss of affinity, with one exception: 2-fluoroadenine was at least as potent as adenine itself at the cAdeR. Structure-activity relationships at all AdeR orthologs and subtypes investigated so far were similar, but not identical. For functional analyses, the cAdeR was homologously expressed in Chinese hamster ovary (CHO) cells, while the mAde1R was heterologously expressed in 1321N1 astrocytoma cells. Like the previously described AdeRs from rat (rAdeR) and mouse (mAde2R), the mAde1R (EC50 9.77 nM) and the cAdeR (EC50 51.6 nM) were coupled to inhibition of adenylate cyclase. In addition, the cAdeR from hamster expressed in CHO cells produced an increase in intracellular calcium concentrations (EC50 6.24 nM) and was found to be additionally coupled to Gq proteins.
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Affiliation(s)
- Dominik Thimm
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Melanie Knospe
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Aliaa Abdelrahman
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Miguel Moutinho
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Bernt B. A. Alsdorf
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Ivar von Kügelgen
- />PharmaCenter Bonn, Department of Pharmacology, University of Bonn, Sigmund-Freud-Straße 25, 53127 Bonn, Germany
| | - Anke C. Schiedel
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Christa E. Müller
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
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Li X, Li PCH. Strategies for the real-time detection of Ca2+ channel events of single cells: recent advances and new possibilities. Expert Rev Clin Pharmacol 2012; 3:267-80. [PMID: 22111609 DOI: 10.1586/ecp.10.16] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Ca(2+) ion channels play key roles in cell physiology and they are important drug targets. The Ca(2+) channel events are mainly measurable by fluorescent and patch clamp methods. This review summarizes the recent advances of these techniques for the detection of Ca(2+) channel events and the prospect of their new directions in the near future. Conventional bulk fluorescent methods are amenable to high-throughput applications, but they are not real-time single-cell measurements, which provide kinetic data on individual cells and offer unparalleled sensitive data for rare cells. Recent advances on real-time single-cell fluorescent measurements are conducted on microfluidic chips with scalable cell-retention sites, integrated with electrical stimulation and fluorescent measuring features. Patch clamp techniques are real-time measurements conducted on single cells, but the measurements are of low throughput. Recent advances are conducted on microfluidic patch clamp chips for high-throughput applications. Future real-time single-cell Ca(2+) channel event measurements will be conducted in a multiparametric manner in an integrated and automated microfluidic chip.
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Affiliation(s)
- XiuJun Li
- University of California at Berkeley, CA 94720, USA
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Borrmann T, Abdelrahman A, Volpini R, Lambertucci C, Alksnis E, Gorzalka S, Knospe M, Schiedel AC, Cristalli G, Müller CE. Structure−Activity Relationships of Adenine and Deazaadenine Derivatives as Ligands for Adenine Receptors, a New Purinergic Receptor Family. J Med Chem 2009; 52:5974-89. [DOI: 10.1021/jm9006356] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Thomas Borrmann
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Aliaa Abdelrahman
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Rosaria Volpini
- Dipartimento di Scienze Chimiche, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy
| | - Catia Lambertucci
- Dipartimento di Scienze Chimiche, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy
| | - Edgars Alksnis
- Latvian Institute of Organic Synthesis, Aizkraukles iela 21, Riga LV-1006, Latvia
| | - Simone Gorzalka
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Melanie Knospe
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Anke C. Schiedel
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Gloria Cristalli
- Dipartimento di Scienze Chimiche, University of Camerino, Via S. Agostino 1, 62032 Camerino, Italy
| | - Christa E. Müller
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
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von Kügelgen I, Schiedel AC, Hoffmann K, Alsdorf BBA, Abdelrahman A, Müller CE. Cloning and Functional Expression of a Novel GiProtein-Coupled Receptor for Adenine from Mouse Brain. Mol Pharmacol 2007; 73:469-77. [DOI: 10.1124/mol.107.037069] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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