Abstract
P2X receptors are cation-selective ion channels gated by extracellular ATP, and are implicated in diverse physiological processes, from synaptic transmission to inflammation to the sensing of taste and pain. Because P2X receptors are not related to other ion channel proteins of known structure, there is at present no molecular foundation for mechanisms of ligand-gating, allosteric modulation and ion permeation. Here we present crystal structures of the zebrafish P2X4 receptor in its closed, resting state. The chalice-shaped, trimeric receptor is knit together by subunit–subunit contacts implicated in ion channel gating and receptor assembly. Extracellular domains, rich in β-strands, have large acidic patches that may attract cations, through fenestrations, to vestibules near the ion channel. In the transmembrane pore, the ‘gate’ is defined by an ∼8 Å slab of protein. We define the location of three non-canonical, intersubunit ATP-binding sites, and suggest that ATP binding promotes subunit rearrangement and ion channel opening.
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References
Holton, F. A. & Holton, P. The capillary dilator substances in dry powders of spinal roots; a possible role of adenosine triphosphate in chemical transmission from nerve endings. J. Physiol. (Lond.) 126, 124–140 (1954)
Burnstock, G. Purinergic nerves. Pharmacol. Rev. 24, 509–581 (1972)
Valera, S. et al. A new class of ligand-gated ion channel defined by P2x receptor for extracellular ATP. Nature 371, 516–519 (1994)
Lustig, K. D., Shiau, A. K., Brake, A. J. & Julius, D. Expression cloning of an ATP receptor from mouse neuroblastoma cells. Proc. Natl Acad. Sci. USA 90, 5113–5117 (1993)
Webb, T. E. et al. Cloning and functional expression of a brain G-protein-coupled ATP receptor. FEBS Lett. 324, 219–225 (1993)
Brake, A. J., Wagenbach, M. J. & Julius, D. New structural motif for ligand-gated ion channels defined by an ionotropic ATP receptor. Nature 371, 519–523 (1994)
Schwiebert, E. M. & Zsembery, A. Extracellular ATP as a signaling molecule for epithelial cells. Biochim. Biophys. Acta 1615, 7–32 (2003)
Surprenant, A. & North, R. A. Signaling at purinergic P2X receptors. Annu. Rev. Physiol. 71, 333–359 (2008)
Khakh, B. S. & Henderson, G. ATP receptor-mediated enhancement of fast excitatory neurotransmitter release in the brain. Mol. Pharmacol. 54, 372–378 (1998)
Gu, J. G. & MacDermott, A. B. Activation of ATP P2X receptors elicits glutamate release from sensory neuron synapses. Nature 389, 749–753 (1997)
Hugel, S. & Schlichter, R. Presynaptic P2X receptors facilitate inhibitory GABAergic transmission between cultured rat spinal cord dorsal horn neurons. J. Neurosci. 20, 2121–2130 (2000)
Donato, R. et al. GABA release by basket cells onto Purkinje cells, in rat cerebellar slices, is directly controlled by presynaptic purinergic receptors, modulating Ca2+ influx. Cell Calcium 44, 521–532 (2008)
Edwards, F. A., Gibb, A. J. & Colquhoun, D. ATP receptor-mediated synaptic currents in the central nervous system. Nature 359, 144–147 (1992)
Sim, J. A. et al. Altered hippocampal synaptic potentiation in P2X4 knock-out mice. J. Neurosci. 26, 9006–9009 (2006)
Finger, T. E. et al. ATP signaling is crucial for communication from taste buds to gustatory nerves. Science 310, 1495–1499 (2005)
Cook, S. P., Vulchanova, L., Hargreaves, K. M., Elde, R. & McCleskey, E. W. Distinct ATP receptors on pain-sensing and stretch-sensing neurons. Nature 387, 505–508 (1997)
Souslova, V. et al. Warm-coding deficits and aberrant inflammatory pain in mice lacking P2X3 receptors. Nature 407, 1015–1017 (2000)
Cockayne, D. A. et al. Urinary bladder hyporeflexia and reduced pain-related behaviour in P2X3-deficient mice. Nature 407, 1011–1015 (2000)
Chessell, I. P. et al. Disruption of the P2X7 purinoceptor gene abolishes chronic inflammatory and neuropathic pain. Pain 114, 386–396 (2005)
Yamamoto, K. et al. Impaired flow-dependent control of vascular tone and remodeling in P2X4-deficient mice. Nature Med. 12, 133–137 (2006)
Inscho, E. W., Cook, A. K., Imig, J. D., Vial, C. & Evans, R. J. Renal autoregulation in P2X1 knockout mice. Acta Physiol. Scand. 181, 445–453 (2004)
Solle, M. et al. Altered cytokine production in mice lacking P2X7 receptors. J. Biol. Chem. 276, 125–132 (2001)
White, N. & Burnstock, G. P2 receptors and cancer. Trends Pharmacol. Sci. 27, 211–217 (2006)
Di Virgilio, F. Liaisons dangereuses: P2X7 and the inflammasome. Trends Pharmacol. Sci. 28, 465–472 (2007)
North, R. A. Molecular physiology of P2X receptors. Physiol. Rev. 82, 1013–1067 (2002)
Aschrafi, A., Sadtler, S., Niculescu, C., Rettinger, J. & Schmalzing, G. Trimeric architecture of homomeric P2X2 and heteromeric P2X1+2 receptor subtypes. J. Mol. Biol. 342, 333–343 (2004)
Barrera, N. P., Ormond, S. J., Henderson, R. M., Murrell-Lagnado, R. D. & Edwardson, J. M. Atomic force microscopy imaging demonstrates that P2X2 receptors are trimers but that P2X6 receptor subunits do not oligomerize. J. Biol. Chem. 280, 10759–10765 (2005)
Nicke, A. et al. P2X1 and P2X3 receptors form stable trimers: a novel structural motif of ligand-gated ion channels. EMBO J. 17, 3016–3028 (1998)
Nicke, A., Rettinger, J. & Schmalzing, G. Monomeric and dimeric byproducts are the principal functional elements of higher order P2X1 concatamers. Mol. Pharmacol. 63, 243–252 (2003)
North, R. A. & Surprenant, A. Pharmacology of cloned P2X receptors. Annu. Rev. Pharmacol. Toxicol. 40, 563–580 (2000)
Kellenberger, S. & Schild, L. Epithelial sodium channel/degenerin family of ion channels: a variety of functions for a shared structure. Physiol. Rev. 82, 735–767 (2002)
Kawate, T. & Gouaux, E. Fluorescence-detection size-exclusion chromatography for precrystallization screening of integral membrane proteins. Structure 14, 673–681 (2006)
Diaz-Hernandez, M. et al. Cloning and characterization of two novel zebrafish P2X receptor subunits. Biochem. Biophys. Res. Commun. 295, 849–853 (2002)
Blake, C. C., Geisow, M. J., Oatley, S. J., Rerat, B. & Rerat, C. Structure of prealbumin: secondary, tertiary and quaternary interactions determined by Fourier refinement at 1.8 Å. J. Mol. Biol. 121, 339–356 (1978)
Williams, D. C., Lee, J. Y., Cai, M., Bewley, C. A. & Clore, G. M. Crystal structures of the HIV-1 inhibitory cyanobacterial protein MVL free and bound to Man3GlcNAc2: structural basis for specificity and high-affinity binding to the core pentasaccharide from n-linked oligomannoside. J. Biol. Chem. 280, 29269–29276 (2005)
Ennion, S. J. & Evans, R. J. Conserved cysteine residues in the extracellular loop of the human P2X1 receptor form disulfide bonds and are involved in receptor trafficking to the cell surface. Mol. Pharmacol. 61, 303–311 (2002)
Clyne, J. D., Wang, L. F. & Hume, R. I. Mutational analysis of the conserved cysteines of the rat P2X2 purinoceptor. J. Neurosci. 22, 3873–3880 (2002)
Fabbretti, E. et al. Identification of negative residues in the P2X3 ATP receptor ectodomain as structural determinants for desensitization and the Ca2+-sensing modulatory sites. J. Biol. Chem. 279, 53109–53115 (2004)
Duckwitz, W., Hausmann, R., Aschrafi, A. & Schmalzing, G. P2X5 subunit assembly requires scaffolding by the second transmembrane domain and a conserved aspartate. J. Biol. Chem. 281, 39561–39572 (2006)
Li, M., Chang, T. H., Silberberg, S. D. & Swartz, K. J. Gating the pore of P2X receptor channels. Nature Neurosci. 11, 883–887 (2008)
Gonzales, E. B., Kawate, T. & Gouaux, E. Pore architecture and ion sites in acid-sensing ion channels and P2X receptors. Nature 10.1038/nature08218 (this issue)
Ennion, S., Hagan, S. & Evans, R. J. The role of positively charged amino acids in ATP recognition by human P2X1 receptors. J. Biol. Chem. 275, 29361–29367 (2000)
Roberts, J. A. & Evans, R. J. ATP binding at human P2X1 receptors. Contribution of aromatic and basic amino acids revealed using mutagenesis and partial agonists. J. Biol. Chem. 279, 9043–9055 (2004)
Jiang, L. H., Rassendren, F., Surprenant, A. & North, R. A. Identification of amino acid residues contributing to the ATP-binding site of a purinergic P2X receptor. J. Biol. Chem. 275, 34190–34196 (2000)
Roberts, J. A. & Evans, R. J. Contribution of conserved polar glutamine, asparagine and threonine residues and glycosylation to agonist action at human P2X1 receptors for ATP. J. Neurochem. 96, 843–852 (2006)
Marquez-Klaka, B., Rettinger, J., Bhargava, Y., Eisele, T. & Nicke, A. Identification of an intersubunit cross-link between substituted cysteine residues located in the putative ATP binding site of the P2X1 receptor. J. Neurosci. 27, 1456–1466 (2007)
Michel, A. D. et al. Identification of regions of the P2X7 receptor that contribute to human and rat species differences in antagonist effects. Br. J. Pharmacol. 155, 738–751 (2008)
Sim, J. A., Broomhead, H. E. & North, R. A. Ectodomain lysines and suramin block of P2X1 receptors. J. Biol. Chem. 283, 29841–29846 (2008)
Smart, O. S., Goodfellow, J. M. & Wallace, B. A. The pore dimensions of gramicidin A. Biophys. J. 65, 2455–2460 (1993)
Baker, N. A., Sept, D., Joseph, S., Holst, M. J. & McCammon, J. A. Electrostatics of nanosystems: application to microtubules and the ribosome. Proc. Natl Acad. Sci. USA 98, 10037–10041 (2001)
Diaz-Hernandez, M. et al. Cloning and characterization of two novel zebrafish P2X receptor subunits. Biochem. Biophys. Res. Commun. 295, 849–853 (2002)
Kucenas, S. et al. Molecular characterization of the zebrafish P2X receptor subunit gene family. Neuroscience 121, 935–945 (2003)
Acknowledgements
We thank the personnel at beamlines 5.0.2, 8.2.1 and 8.2.2 of the Advanced Light Source and at beamline 24-ID-E of the Advanced Photon Source. We also thank M. Voigt for zebrafish P2X receptor DNA, T. Homrichhausen for help with cloning and FSEC screening, J. Berriman for help with electron microscopy, L. Vaskalis for assistance with illustrations, and Gouaux laboratory members for discussions. This work was supported by the National Institutes of Health (NIH) and the American Asthma Foundation. E.G. is an investigator with the Howard Hughes Medical Institute.
Author Contributions E.G. and T.K. designed the project. T.K. performed cloning, cell culture, FSEC screening, purification, characterization, electron microscopy and crystallography. J.C.M. performed cloning, cell culture, FSEC screening, purification and crystallization. W.T.B. carried out the electrophysiology. All authors contributed to writing the manuscript.
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Kawate, T., Michel, J., Birdsong, W. et al. Crystal structure of the ATP-gated P2X4 ion channel in the closed state. Nature 460, 592–598 (2009). https://doi.org/10.1038/nature08198
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DOI: https://doi.org/10.1038/nature08198
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