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Györi J, Kohn AB, Romanova DY, Moroz LL. ATP signaling in the integrative neural center of Aplysia californica. Sci Rep 2021; 11:5478. [PMID: 33750901 PMCID: PMC7943599 DOI: 10.1038/s41598-021-84981-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/23/2021] [Indexed: 11/22/2022] Open
Abstract
ATP and its ionotropic P2X receptors are components of the most ancient signaling system. However, little is known about the distribution and function of purinergic transmission in invertebrates. Here, we cloned, expressed, and pharmacologically characterized the P2X receptors in the sea slug Aplysia californica—a prominent neuroscience model. AcP2X receptors were successfully expressed in Xenopus oocytes and displayed activation by ATP with two-phased kinetics and Na+-dependence. Pharmacologically, they were different from other P2X receptors. The ATP analog, Bz-ATP, was a less effective agonist than ATP, and PPADS was a more potent inhibitor of the AcP2X receptors than the suramin. AcP2X were uniquely expressed within the cerebral F-cluster, the multifunctional integrative neurosecretory center. AcP2X receptors were also detected in the chemosensory structures and the early cleavage stages. Therefore, in molluscs, rapid ATP-dependent signaling can be implicated both in development and diverse homeostatic functions. Furthermore, this study illuminates novel cellular and systemic features of P2X-type ligand-gated ion channels for deciphering the evolution of neurotransmitters.
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Affiliation(s)
- János Györi
- Department of Experimental Zoology, Centre for Ecological Research, Balaton Limnological Institute, 8237, Tihany, Hungary.,Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA
| | - Andrea B Kohn
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA
| | - Daria Y Romanova
- Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow, 117485, Russia
| | - Leonid L Moroz
- Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, 32080, USA. .,Departments of Neuroscience and McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA.
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Jové V, Gong Z, Hol FJH, Zhao Z, Sorrells TR, Carroll TS, Prakash M, McBride CS, Vosshall LB. Sensory Discrimination of Blood and Floral Nectar by Aedes aegypti Mosquitoes. Neuron 2020; 108:1163-1180.e12. [PMID: 33049200 PMCID: PMC9831381 DOI: 10.1016/j.neuron.2020.09.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 07/13/2020] [Accepted: 09/11/2020] [Indexed: 02/06/2023]
Abstract
Blood-feeding mosquitoes survive by feeding on nectar for metabolic energy but require a blood meal to develop eggs. Aedes aegypti females must accurately discriminate blood and nectar because each meal promotes mutually exclusive feeding programs with distinct sensory appendages, meal sizes, digestive tract targets, and metabolic fates. We investigated the syringe-like blood-feeding appendage, the stylet, and discovered that sexually dimorphic stylet neurons taste blood. Using pan-neuronal calcium imaging, we found that blood is detected by four functionally distinct stylet neuron classes, each tuned to specific blood components associated with diverse taste qualities. Stylet neurons are insensitive to nectar-specific sugars and respond to glucose only in the presence of additional blood components. The distinction between blood and nectar is therefore encoded in specialized neurons at the very first level of sensory detection in mosquitoes. This innate ability to recognize blood is the basis of vector-borne disease transmission to millions of people worldwide.
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Affiliation(s)
- Veronica Jové
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY 10065, USA
| | - Zhongyan Gong
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY 10065, USA
| | - Felix J H Hol
- Insect-Virus Interactions Unit, Department of Virology, Institut Pasteur, 75724 Paris, France; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Zhilei Zhao
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA
| | - Trevor R Sorrells
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY 10065, USA; Kavli Neural Systems Institute, New York, NY 10065, USA
| | - Thomas S Carroll
- Bioinformatics Resource Center, The Rockefeller University, New York, NY 10065, USA
| | - Manu Prakash
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford, CA 94305, USA
| | - Carolyn S McBride
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA
| | - Leslie B Vosshall
- Laboratory of Neurogenetics and Behavior, The Rockefeller University, New York, NY 10065, USA; Kavli Neural Systems Institute, New York, NY 10065, USA; Howard Hughes Medical Institute, New York, NY 10065, USA.
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Verkhratsky A. Early evolutionary history (from bacteria to hemichordata) of the omnipresent purinergic signalling: A tribute to Geoff Burnstock inquisitive mind. Biochem Pharmacol 2020; 187:114261. [PMID: 33011161 DOI: 10.1016/j.bcp.2020.114261] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 12/11/2022]
Abstract
Purines and pyrimidines are indispensable molecules of life; they are fundamental for genetic code and bioenergetics. From the very early evolution of life purines have acquired the meaning of damage-associated extracellular signaller and purinergic receptors emerged in unicellular organisms. Ancestral purinoceptors are P2X-like ionotropic ligand-gated cationic channels showing 20-40% of homology with vertebrate P2X receptors; genes encoding ancestral P2X receptors have been detected in Protozoa, Algae, Fungi and Sponges; they are also present in some invertebrates, but are absent from the genome of insects, nematodes, and higher plants. Plants nevertheless evolved a sophisticated and widespread purinergic signalling system relying on the idiosyncratic purinoceptor P2K1/DORN1 linked to intracellular Ca2+ signalling. The advance of metabotropic purinoceptors starts later in evolution with adenosine receptors preceding the emergence of P2Y nucleotide and P0 adenine receptors. In vertebrates and mammals the purinergic signalling system reaches the summit and operates throughout all tissues and systems without anatomical or functional segregation.
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Affiliation(s)
- Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PT, United Kingdom; Achucarro Center for Neuroscience, IKERBASQUE, 48011 Bilbao, Spain.
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Vijayamahantesh, Vijayalaxmi. Tinkering with targeting nucleotide signaling for control of intracellular Leishmania parasites. Cytokine 2019; 119:129-143. [PMID: 30909149 DOI: 10.1016/j.cyto.2019.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 03/12/2019] [Accepted: 03/13/2019] [Indexed: 12/23/2022]
Abstract
Nucleotides are one of the most primitive extracellular signalling molecules across all phyla and regulate a multitude of responses. The biological effects of extracellular nucleotides/sides are mediated via the specific purinergic receptors present on the cell surface. In mammalian system, adenine nucleotides are the predominant nucleotides found in the extracellular milieu and mediate a constellation of physiological functions. In the context of host-pathogen interaction, extracellular ATP is recognized as a danger signal and potentiates the release of pro-inflammatory mediators from activated immune cells, on the other hand, its breakdown product adenosine exerts potential anti-inflammatory and immunosuppressive actions. Therefore, it is increasingly apparent that the interplay between extracellular ATP/adenosine ratios has a significant role in coordinating the regulation of the immune system in health and diseases. Several pathogens express ectonucleotidases on their surface and exploit the purinergic signalling as one of the mechanisms to modulate the host immune response. Leishmania pathogens are one of the most successful intracellular pathogens which survive within host macrophages and manipulate protective Th1 response into disease promoting Th2 response. In this review, we discuss the regulation of extracellular ATP and adenosine levels, the role of ATP/adenosine counter signalling in regulating the inflammation and immune responses during infection and how Leishmania parasites exploit the purinergic signalling to manipulate host response. We also discuss the challenges and opportunities in targeting purinergic signalling and the future prospects.
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Affiliation(s)
- Vijayamahantesh
- Department of Biochemistry, Indian Institute of Science (IISc), Bengaluru, Karnataka, India.
| | - Vijayalaxmi
- Department of Zoology, Karnatak University, Dharwad, Karnataka, India
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Hausmann R, Kless A, Schmalzing G. Key sites for P2X receptor function and multimerization: overview of mutagenesis studies on a structural basis. Curr Med Chem 2015; 22:799-818. [PMID: 25439586 PMCID: PMC4460280 DOI: 10.2174/0929867322666141128163215] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 10/20/2014] [Accepted: 11/27/2014] [Indexed: 02/07/2023]
Abstract
P2X receptors constitute a seven-member family (P2X1-7) of extracellular ATP-gated cation
channels of widespread expression. Because P2X receptors have been implicated in neurological, inflammatory
and cardiovascular diseases, they constitute promising drug targets. Since the first P2X cDNA sequences
became available in 1994, numerous site-directed mutagenesis studies have been conducted to disclose
key sites of P2X receptor function and oligomerization. The publication of the 3-Å crystal structures of the zebrafish
P2X4 (zfP2X4) receptor in the homotrimeric apo-closed and ATP-bound open states in 2009 and 2012, respectively, has
ushered a new era by allowing for the interpretation of the wealth of molecular data in terms of specific three-dimensional
models and by paving the way for designing more-decisive experiments. Thanks to these structures, the last five years
have provided invaluable insight into our understanding of the structure and function of the P2X receptor class of ligandgated
ion channels. In this review, we provide an overview of mutagenesis studies of the pre- and post-crystal structure
eras that identified amino acid residues of key importance for ligand binding, channel gating, ion flow, formation of the
pore and the channel gate, and desensitization. In addition, the sites that are involved in the trimerization of P2X receptors
are reviewed based on mutagenesis studies and interface contacts that were predicted by the zfP2X4 crystal structures.
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Affiliation(s)
| | | | - Gunther Schmalzing
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, D-52074 Aachen, Germany.
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Evidence for Extracellular ATP as a Stress Signal in a Single-Celled Organism. EUKARYOTIC CELL 2015; 14:775-82. [PMID: 26048010 DOI: 10.1128/ec.00066-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 05/28/2015] [Indexed: 01/18/2023]
Abstract
ATP is omnipresent in biology and acts as an extracellular signaling molecule in mammals. Information regarding the signaling function of extracellular ATP in single-celled eukaryotes is lacking. Here, we explore the role of extracellular ATP in cell volume recovery during osmotic swelling in the amoeba Dictyostelium. Release of micromolar ATP could be detected during cell swelling and regulatory cell volume decrease (RVD) phases during hypotonic challenge. Scavenging ATP with apyrase caused profound cell swelling and loss of RVD. Apyrase-induced swelling could be rescued by 100 μM βγ-imidoATP. N-Ethylmalemide (NEM), an inhibitor of vesicular exocytosis, caused heightened cell swelling, loss of RVD, and inhibition of ATP release. Amoebas with impaired contractile vacuole (CV) fusion (drainin knockout [KO] cells) displayed increased swelling but intact ATP release. One hundred micromolar Gd(3+) caused cell swelling while blocking any recovery by βγ-imidoATP. ATP release was 4-fold higher in the presence of Gd(3+). Cell swelling was associated with an increase in intracellular nitric oxide (NO), with NO-scavenging agents causing cell swelling. Swelling-induced NO production was inhibited by both apyrase and Gd(3+), while NO donors rescued apyrase- and Gd(3+)-induced swelling. These data suggest extracellular ATP released during cell swelling is an important signal that elicits RVD. Though the cell surface receptor for ATP in Dictyostelium remains elusive, we suggest ATP operates through a Gd(3+)-sensitive receptor that is coupled with intracellular NO production.
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Hausmann R, Bahrenberg G, Kuhlmann D, Schumacher M, Braam U, Bieler D, Schlusche I, Schmalzing G. A hydrophobic residue in position 15 of the rP2X3 receptor slows desensitization and reveals properties beneficial for pharmacological analysis and high-throughput screening. Neuropharmacology 2014; 79:603-15. [PMID: 24452010 DOI: 10.1016/j.neuropharm.2014.01.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 12/24/2013] [Accepted: 01/09/2014] [Indexed: 11/19/2022]
Abstract
The homotrimeric P2X3 subtype, one of the seven members of the ATP-gated P2X receptor family, plays a role in sensory neurotransmission, including nociception. To overcome the bias resulting from fast desensitization of the P2X3 receptor in dose-response analyses, a non-desensitizing P2X2-X3 receptor chimera has been repeatedly used as a surrogate for the P2X3 receptor for functional analysis. Here, we show that only three of the P2X2-specific amino acid residues of the P2X2-X3 chimera, (19)P(21)V(22)I, are needed to confer a slowly desensitizing phenotype to the P2X3 receptor. The strongest delay in desensitization of the P2X3 receptor by a single residue was observed when (15)Ser was replaced by Val or another hydrophobic residue. Pharmacologically, the S(15)V-rP2X3 mutant behaved similarly to the wt-P2X3 receptor. Analysis of the S(15)V-rP2X3 receptor in 1321N1 astrocytoma cells by a common calcium-imaging-based assay showed 10-fold higher calcium transients relative to those of the wt-rP2X3 receptor. The S(15)V-rP2X3 cell line enabled reliable analysis of antagonistic potencies and correctly reported the mechanism of action of the P2X3 receptor antagonists A-317491 and TNP-ATP by a calcium-imaging assay. Together, these data suggest that the S(15)V-rP2X3 mutant may be suitable not only for automated fluorescence-based screening of molecule libraries for identification of lead compounds but also for facilitated pharmacological characterization of specific P2X3 receptor ligands. We suggest that the mechanism of desensitization of the P2X3 receptor may involve the movement of an N-terminal inactivation particle, in analogy to the "hinged-lid" or "ball and chain" mechanisms of voltage-gated NaV and Shaker KV channels, respectively.
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Affiliation(s)
- Ralf Hausmann
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany.
| | - Gregor Bahrenberg
- Grünenthal GmbH, Global Drug Discovery, Department of Molecular Pharmacology, Zieglerstrasse 6, 52078 Aachen, Germany
| | - Daniel Kuhlmann
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Michaela Schumacher
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Ursula Braam
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
| | - Dagmar Bieler
- Grünenthal GmbH, Global Drug Discovery, Department of Molecular Pharmacology, Zieglerstrasse 6, 52078 Aachen, Germany
| | - Ilka Schlusche
- Grünenthal GmbH, Global Drug Discovery, Department of Molecular Pharmacology, Zieglerstrasse 6, 52078 Aachen, Germany
| | - Günther Schmalzing
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, 52074 Aachen, Germany
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Fountain SJ. Primitive ATP-activated P2X receptors: discovery, function and pharmacology. Front Cell Neurosci 2013; 7:247. [PMID: 24367292 PMCID: PMC3853471 DOI: 10.3389/fncel.2013.00247] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 11/19/2013] [Indexed: 12/02/2022] Open
Abstract
Adenosine 5-triphosphate (ATP) is omnipresent in biology. It is therefore no surprise that organisms have evolved multifaceted roles for ATP, exploiting its abundance and restriction of passive diffusion across biological membranes. A striking role is the emergence of ATP as a bona fide transmitter molecule, whereby the movement of ATP across membranes serves as a chemical message through a direct ligand-receptor interaction. P2X receptors are ligand-gated ion channels that mediate fast responses to the transmitter ATP in mammalian cells including central and sensory neurons, vascular smooth muscle, endothelium, and leukocytes. Molecular cloning of P2X receptors and our understanding of structure-function relationships has provided sequence information with which to query an exponentially expanding wealth of genome sequence information including protist, early animal and human pathogen genomes. P2X receptors have now been cloned and characterized from a number of simple organisms. Such work has led to surprising new cellular roles for the P2X receptors family and an unusual phylogeny, with organisms such as Drosophila and C. elegans notably lacking P2X receptors despite retaining ionotropic receptors for other common transmitters that are present in mammals. This review will summarize current work on the evolutionary biology of P2X receptors and ATP as a signaling molecule, discuss what can be drawn from such studies when considering the action of ATP in higher animals and plants, and outline how simple organisms may be exploited experimentally to inform P2X receptor function in a wider context.
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Affiliation(s)
- Samuel J Fountain
- School of Biological Sciences, University of East Anglia Norwich, UK
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Sivaramakrishnan V, Fountain SJ. Intracellular P2X receptors as novel calcium release channels and modulators of osmoregulation in Dictyostelium: a comparison of two common laboratory strains. Channels (Austin) 2012; 7:43-6. [PMID: 23221467 DOI: 10.4161/chan.22737] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
P2X receptors are calcium permeable ligand-gated ion channels activated by ATP. Their role as cell surface receptors for extracellular ATP released physiologically by mammalian cells is well established. However, the cellular function of P2X receptor subtypes that populate the membranes of intracellular compartments is not defined. An initial report described how intracellular P2X receptors control the function of the contractile vacuole, an osmoregulatory organelle in Dictyostelium and other protists, and that genetic disruption of P2X receptors severely impaired cell volume control during hypotonic stress. However, later studies refuted a functional role of intracellular P2X receptors in Dictyostelium. Here we provide evidence that the discrepancies reported between the studies are due to the laboratory strain of Dictyostelium employed, which display different phenotypes in response to hypotonic stress and a varied dependency upon P2X receptors for osmoregulation. We use the recent discovery that intracellular P2X receptors are novel calcium release channels to provide some mechanistic insight in an effort to explain why the strain variance may exist.
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Cloning and characterization of a P2X receptor expressed in the central nervous system of Lymnaea stagnalis. PLoS One 2012; 7:e50487. [PMID: 23209755 PMCID: PMC3510196 DOI: 10.1371/journal.pone.0050487] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 10/22/2012] [Indexed: 02/07/2023] Open
Abstract
P2X receptors are membrane ion channels gated by extracellular ATP. Mammals possess seven distinct P2X subtypes (P2X1-7) that have important functions in a wide array of physiological processes including roles in the central nervous system (CNS) where they have been linked to modulation of neurotransmitter release. We report here the cloning and functional characterization of a P2X receptor from the mollusc Lymnaea stagnalis. This model organism has a relatively simple CNS consisting of large readily identifiable neurones, a feature which together with a well characterized neuronal circuitry for important physiological processes such as feeding and respiration makes it an attractive potential model to examine P2X function. Using CODEHOP PCR we identified a single P2X receptor (LymP2X) in Lymnaea CNS which was subsequently cloned by RT-PCR. When heterologously expressed in Xenopus oocytes, LymP2X exhibited ATP evoked inward currents (EC(50) 6.2 µM) which decayed during the continued presence of agonist. UTP and ADP did not activate the receptor whereas αβmeATP was a weak agonist. BzATP was a partial agonist with an EC(50) of 2.4 µM and a maximal response 33% smaller than that of ATP. The general P2 receptor antagonists PPADS and suramin both inhibited LymP2X currents with IC(50) values of 8.1 and 27.4 µM respectively. LymP2X is inhibited by acidic pH whereas Zn(2+) and Cu(2+) ions exhibited a biphasic effect, potentiating currents up to 100 µM and inhibiting at higher concentrations. Quantitative RT-PCR and in situ hybridization detected expression of LymP2X mRNA in neurones of all CNS ganglia suggesting this ion channel may have widespread roles in Lymnaea CNS function.
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Allsopp RC, Evans RJ. The intracellular amino terminus plays a dominant role in desensitization of ATP-gated P2X receptor ion channels. J Biol Chem 2011; 286:44691-701. [PMID: 22027824 PMCID: PMC3247974 DOI: 10.1074/jbc.m111.303917] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
P2X receptors show marked variations in the time-course of response to ATP application from rapidly desensitizing P2X1 receptors to relatively sustained P2X2 receptors. In this study we have used chimeras between human P2X1 and P2X2 receptors in combination with mutagenesis to address the contribution of the extracellular ligand binding loop, the transmembrane channel, and the intracellular regions to receptor time-course. Swapping either the extracellular loop or both transmembrane domains (TM1 and -2) between the P2X1 and P2X2 receptors had no effect on the time-course of ATP currents in the recipient receptor. These results suggest that the agonist binding and channel-forming portions of the receptor do not play a major role in the control of the time-course. In contrast replacing the amino terminus of the P2X1 receptor with that from the non-desensitizing P2X2 receptor (P2X1-2N) slowed desensitization, and the mirror chimera induced rapid desensitization in the P2X2-1N chimera. These reciprocal effects on time-course can be replicated by changing four variant amino acids just before the first transmembrane (TM1) segment. These pre-TM1 residues also had a dominant effect on chimeras where both TMs had been transferred; mutating the variant amino acids 21-23 to those found in the P2X2 receptor removed desensitization from the P2X1-2TM1/-2 chimera, and the reciprocal mutants induced rapid desensitization in the non-desensitizing P2X2-1TM1/-2 chimera. These results suggest that the intracellular amino terminus, in particular the region just before TM1, plays a dominant role in the regulation of the time-course of ATP evoked P2X receptor currents.
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Affiliation(s)
- Rebecca C Allsopp
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester LE1 9HN, United Kingdom
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