101
|
Lennertz RC, Tsunozaki M, Bautista DM, Stucky CL. Physiological basis of tingling paresthesia evoked by hydroxy-alpha-sanshool. J Neurosci 2010; 30:4353-61. [PMID: 20335471 PMCID: PMC2852189 DOI: 10.1523/jneurosci.4666-09.2010] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 12/23/2009] [Accepted: 02/11/2010] [Indexed: 12/15/2022] Open
Abstract
Hydroxy-alpha-sanshool, the active ingredient in plants of the prickly ash plant family, induces robust tingling paresthesia by activating a subset of somatosensory neurons. However, the subtypes and physiological function of sanshool-sensitive neurons remain unknown. Here we use the ex vivo skin-nerve preparation to examine the pattern and intensity with which the sensory terminals of cutaneous neurons respond to hydroxy-alpha-sanshool. We found that sanshool excites virtually all D-hair afferents, a distinct subset of ultrasensitive light-touch receptors in the skin and targets novel populations of Abeta and C fiber nerve afferents. Thus, sanshool provides a novel pharmacological tool for discriminating functional subtypes of cutaneous mechanoreceptors. The identification of sanshool-sensitive fibers represents an essential first step in identifying the cellular and molecular mechanisms underlying tingling paresthesia that accompanies peripheral neuropathy and injury.
Collapse
Affiliation(s)
- Richard C. Lennertz
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| | - Makoto Tsunozaki
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720
| | - Diana M. Bautista
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720
| | - Cheryl L. Stucky
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| |
Collapse
|
102
|
Czirják G, Enyedi P. TRESK background K(+) channel is inhibited by phosphorylation via two distinct pathways. J Biol Chem 2010; 285:14549-57. [PMID: 20215114 DOI: 10.1074/jbc.m110.102020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The two-pore domain K(+) channel, TRESK (TWIK-related spinal cord K(+) channel, KCNK18) is directly regulated by the calcium/calmodulin-dependent phosphatase calcineurin and 14-3-3 adaptor proteins. The calcium signal robustly activates the channel via calcineurin, whereas the anchoring of 14-3-3 interferes with the return of the current to the resting state after the activation in Xenopus oocytes. In the present study, we report that the phosphorylation of TRESK at two distinct regulatory regions, the 14-3-3 binding site (Ser-264) and the cluster of three adjacent serine residues (Ser-274, Ser-276, and Ser-279), are responsible for channel inhibition. The phosphorylation of Ser-264 by protein kinase A accelerated the return of the current of S276E mutant TRESK to the resting state after the calcineurin-dependent activation. In the presence of 14-3-3, the basal current of the S276E mutant was reduced, and its calcineurin-dependent activation was augmented, suggesting that the direct binding of the adaptor protein to TRESK contributed to the basal inhibition of the channel under resting conditions. Unexpectedly, we found that 14-3-3 impeded the recovery of the current of S264E mutant TRESK to the resting state after the calcineurin-dependent activation, despite of the mutated 14-3-3 binding site. This suggests that 14-3-3 inhibited the kinase phosphorylating the regulatory cluster of Ser-274, Ser-276, and Ser-279, independently of the direct interaction between TRESK and 14-3-3. In conclusion, two distinct inhibitory kinase pathways converge on TRESK, and their effect on the calcineurin-dependent regulation is differentially modulated by the functional availability of 14-3-3.
Collapse
Affiliation(s)
- Gábor Czirják
- Department of Physiology, Semmelweis University, H-1444 Budapest, Hungary
| | | |
Collapse
|
103
|
Two-pore potassium ion channels are inhibited by both G(q/11)- and G(i)-coupled P2Y receptors. Mol Cell Neurosci 2010; 43:363-9. [PMID: 20097289 DOI: 10.1016/j.mcn.2010.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 01/07/2010] [Accepted: 01/13/2010] [Indexed: 12/16/2022] Open
Abstract
Two-pore potassium (K(2P)) ion channels and P2Y receptors modulate the activity of neurones and are targets for the treatment of neuronal disorders. Here we have characterised their interaction. In cells coexpressing the Galpha(i)-coupled hP2Y(12) receptor, ADP and ATP significantly inhibited hK(2P)2.1 currents. This was abolished by pertussis toxin (PTX), the hP2Y(12) antagonist AR-C69931MX, the hP2Y(1) antagonist MRS2179 and by mutating potential PKA/PKC phosphorylation sites in the channel C terminal. In cells coexpressing the Galpha(q/11)-coupled hP2Y(1) receptor, ADP and ATP also inhibited hK(2P)2.1 currents, which were abolished by MRS2179, but unaffected by AR-C69931MX and PTX. When both receptors were coexpressed with K(2P)2.1 channels, ADP-induced inhibition was antagonised by AR-C69913MX and MRS2179, but not PTX. Thus, both Galpha(q/11)- and Galpha(i)-coupled P2Y receptors inhibit K(2P) channels and the action of hP2Y(12) receptors appears to involve co-activation of endogenous hP2Y(1) receptors. This represents a novel mechanism by which P2Y receptors may modulate neuronal activity.
Collapse
|
104
|
N-linked glycosylation determines cell surface expression of two-pore-domain K+ channel TRESK. Biochem Biophys Res Commun 2010; 391:1262-7. [DOI: 10.1016/j.bbrc.2009.12.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 12/09/2009] [Indexed: 11/21/2022]
|
105
|
Abstract
The nervous system detects and interprets a wide range of thermal and mechanical stimuli, as well as environmental and endogenous chemical irritants. When intense, these stimuli generate acute pain, and in the setting of persistent injury, both peripheral and central nervous system components of the pain transmission pathway exhibit tremendous plasticity, enhancing pain signals and producing hypersensitivity. When plasticity facilitates protective reflexes, it can be beneficial, but when the changes persist, a chronic pain condition may result. Genetic, electrophysiological, and pharmacological studies are elucidating the molecular mechanisms that underlie detection, coding, and modulation of noxious stimuli that generate pain.
Collapse
Affiliation(s)
- Allan I Basbaum
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94158, USA.
| | | | | | | |
Collapse
|
106
|
Yoo S, Liu J, Sabbadini M, Au P, Xie GX, Yost CS. Regional expression of the anesthetic-activated potassium channel TRESK in the rat nervous system. Neurosci Lett 2009; 465:79-84. [PMID: 19716403 DOI: 10.1016/j.neulet.2009.08.062] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 08/19/2009] [Accepted: 08/24/2009] [Indexed: 01/22/2023]
Abstract
The two-pore-domain potassium (K(2P)) channels contribute to background (leak) potassium currents maintaining the resting membrane potential to play an important role in regulating neuronal excitability. As such they may contribute to nociception and the mechanism of action of volatile anesthetics. In the present study, we examined the protein expression pattern of the K(2P) channel TRESK in the rat central nervous system (CNS) and peripheral nervous system (PNS) by immunohistochemistry. The regional distribution expression pattern of TRESK has both similarities and significant differences from that of other K(2P) channels expressed in the CNS. TRESK expression is broadly found in the brain, spinal cord and dorsal root ganglia (DRG). TRESK expression is highest in important CNS structures, such as specific cortical layers, periaqueductal gray (PAG), granule cell layer of the cerebellum, and dorsal horn of the spinal cord. TRESK expression is also high in small and medium sized DRG neurons. These results provide an anatomic basis for identifying functional roles of TRESK in the rat nervous system.
Collapse
Affiliation(s)
- SieHyeon Yoo
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, 513 Parnassus Avenue, Room S-261, San Francisco, CA 94143, USA
| | | | | | | | | | | |
Collapse
|
107
|
Tsunozaki M, Bautista DM. Mammalian somatosensory mechanotransduction. Curr Opin Neurobiol 2009; 19:362-9. [PMID: 19683913 PMCID: PMC4044613 DOI: 10.1016/j.conb.2009.07.008] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 07/10/2009] [Accepted: 07/13/2009] [Indexed: 11/22/2022]
Abstract
In the mammalian somatosensory system, mechanosensitive neurons mediate the senses of touch and pain. Among sensory modalities, mechanosensation has been the most elusive with regard to the identification of transduction molecules. One factor that has hindered the identification of transduction molecules is the diversity of neurons; physiological studies have revealed many subtypes of neurons, specialized to detect a variety of mechanical stimuli. Do different subtypes use the same transduction molecules that are modified by cellular context? Or, are there multiple mechanotransducers that specialize in sensing different mechanical stimuli? This review highlights recent progress in identifying and characterizing candidate molecular force transducers, as well as the development of new tools to characterize touch transduction at the molecular, cellular, and behavioral levels.
Collapse
Affiliation(s)
- Makoto Tsunozaki
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | | |
Collapse
|
108
|
Molecular Biology of Background K Channels: Insights from K2P Knockout Mice. J Mol Biol 2009; 385:1331-44. [DOI: 10.1016/j.jmb.2008.11.048] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 11/07/2008] [Accepted: 11/19/2008] [Indexed: 12/18/2022]
|
109
|
Abstract
Acidosis is a noxious condition associated with inflammation, ischaemia or defective acid containment. As a consequence, acid sensing has evolved as an important property of afferent neurons with unmyelinated and thinly myelinated nerve fibres. Protons evoke multiple currents in primary afferent neurons, which are carried by several acid-sensitive ion channels. Among these, acid-sensing ion channels (ASICs) and transient receptor potential (TRP) vanilloid-1 (TRPV1) ion channels have been most thoroughly studied. ASICs survey moderate decreases in extracellular pH, whereas TRPV1 is activated only by severe acidosis resulting in pH values below 6. Two-pore-domain K(+) (K(2P)) channels are differentially regulated by small deviations of extra- or intracellular pH from physiological levels. Other acid-sensitive channels include TRPV4, TRPC4, TRPC5, TRPP2 (PKD2L1), ionotropic purinoceptors (P2X), inward rectifier K(+) channels, voltage-activated K(+) channels, L-type Ca(2+) channels, hyperpolarization-activated cyclic nucleotide gated channels, gap junction channels, and Cl(-) channels. In addition, acid-sensitive G protein coupled receptors have also been identified. Most of these molecular acid sensors are expressed by primary sensory neurons, although to different degrees and in various combinations. Emerging evidence indicates that many of the acid-sensitive ion channels and receptors play a role in acid sensing, acid-induced pain and acid-evoked feedback regulation of homeostatic reactions. The existence and apparent redundancy of multiple pH surveillance systems attests to the concept that acid-base regulation is a vital issue for cell and tissue homeostasis. Since upregulation and overactivity of acid sensors appear to contribute to various forms of chronic pain, acid-sensitive ion channels and receptors are considered as targets for novel analgesic drugs. This approach will only be successful if the pathological implications of acid sensors can be differentiated pharmacologically from their physiological function.
Collapse
Affiliation(s)
- Peter Holzer
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Universitätsplatz 4, 8010, Graz, Austria.
| |
Collapse
|
110
|
Emerging roles for two-pore-domain potassium channels and their potential therapeutic impact. Trends Pharmacol Sci 2008; 29:566-75. [PMID: 18823665 DOI: 10.1016/j.tips.2008.07.013] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 07/30/2008] [Accepted: 07/31/2008] [Indexed: 12/21/2022]
Abstract
A distinct gene family of widely distributed and well-modulated two-pore-domain background potassium (K(2P)) channels establish resting membrane potential and cell excitability. By using new mouse models in which K(2P)-channel genes are deleted, the contributions of these channels to important physiological functions are now being revealed. Here, we highlight results of recent studies using mice deleted for K(2P)-channel subunits that uncover physiological functions of these channels, mostly those of the TASK and TREK subgroup. Consistent with activation of these K(2P) channels by volatile anesthetics, TASK-1, TASK-3 and TREK-1 contribute to anesthetic-induced hypnosis and immobilization. The acid-sensitive TASK channels are not required for brainstem control of breathing by CO(2) or pH, despite widespread expression in respiratory-related neurons. TASK channels are necessary, however, for homeostatic regulation of adrenal aldosterone secretion. The heat-, stretch- and lipid-activated TREK-1 channels contribute to temperature and mechanical pain sensation, neuroprotection by polyunsaturated fatty acids and, unexpectedly, mood regulation. The alkaline-activated TASK-2 channel is necessary for HCO(3)(-) reabsorption and osmotic volume regulation in kidney proximal tubule cells. Development of compounds that selectively modulate K(2P) channels is crucial for verifying these results and assessing the efficacy of therapies targeting these interesting channels.
Collapse
|
111
|
Roles of TRESK, a novel two-pore domain K+ channel, in pain pathway and general anesthesia. Neurosci Bull 2008; 24:166-72. [PMID: 18500390 DOI: 10.1007/s12264-008-0225-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
TRESK is the most recently reported two-pore domain K+ channel, and different from other two-pore domain channels in gene, molecular structure, electrophysiological and pharmacological properties. Although the current knowledge of this potassium channel is inadequate, researches have demonstrated that TRESK is remarkablely linked to acute and chronic pain by activation of calcineurin. The fact that TRESK is sensitive to volatile anesthetics and localization in central nerve system implies that TRESK may play a very important role in the mechanism mediating general anesthesia. The further research of TRESK may contribute to explore the underlying mechanism of some pathological conditions and yield novel treatments for some diseases.
Collapse
|
112
|
Bautista DM, Sigal YM, Milstein AD, Garrison JL, Zorn JA, Tsuruda PR, Nicoll RA, Julius D. Pungent agents from Szechuan peppers excite sensory neurons by inhibiting two-pore potassium channels. Nat Neurosci 2008; 11:772-9. [PMID: 18568022 DOI: 10.1038/nn.2143] [Citation(s) in RCA: 180] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Accepted: 05/21/2008] [Indexed: 12/28/2022]
Abstract
In traditional folk medicine, Xanthoxylum plants are referred to as 'toothache trees' because their anesthetic or counter-irritant properties render them useful in the treatment of pain. Psychophysical studies have identified hydroxy-alpha-sanshool as the compound most responsible for the unique tingling and buzzing sensations produced by Szechuan peppercorns or other Xanthoxylum preparations. Although it is generally agreed that sanshool elicits its effects by activating somatosensory neurons, the underlying cellular and molecular mechanisms remain a matter of debate. Here we show that hydroxy-alpha-sanshool excites two types of sensory neurons, including small-diameter unmyelinated cells that respond to capsaicin (but not mustard oil) as well as large-diameter myelinated neurons that express the neurotrophin receptor TrkC. We found that hydroxy-alpha-sanshool excites neurons through a unique mechanism involving inhibition of pH- and anesthetic-sensitive two-pore potassium channels (KCNK3, KCNK9 and KCNK18), providing a framework for understanding the unique and complex psychophysical sensations associated with the Szechuan pepper experience.
Collapse
Affiliation(s)
- Diana M Bautista
- Department of Physiology, University of California, San Francisco, 600 16th St., San Francisco, California 94143-2140, USA
| | | | | | | | | | | | | | | |
Collapse
|
113
|
Czirják G, Vuity D, Enyedi P. Phosphorylation-dependent binding of 14-3-3 proteins controls TRESK regulation. J Biol Chem 2008; 283:15672-80. [PMID: 18397886 PMCID: PMC3259650 DOI: 10.1074/jbc.m800712200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 04/03/2008] [Indexed: 01/04/2023] Open
Abstract
The two-pore domain K(+) channel, TRESK (TWIK-related spinal cord K(+) channel) is reversibly activated by the calcium/calmodulin-dependent protein phosphatase, calcineurin. In the present study, we report that 14-3-3 proteins directly bind to the intracellular loop of TRESK and control the kinetics of the calcium-dependent regulation of the channel. Coexpression of 14-3-3eta with TRESK blocked, whereas the coexpression of a dominant negative form of 14-3-3eta accelerated the return of the K(+) current to the resting state after the activation mediated by calcineurin in Xenopus oocytes. The direct action of 14-3-3 was spatially restricted to TRESK, since 14-3-3eta was also effective, when it was tethered to the channel by a flexible polyglutamine-containing chain. The effect of both the coexpressed and chained 14-3-3 was alleviated by the microinjection of Ser(P)-Raf259 phosphopeptide that competes with TRESK for binding to 14-3-3. The gamma and eta isoforms of 14-3-3 controlled TRESK regulation, whereas the beta, zeta, epsilon, sigma, and tau isoforms failed to influence the mechanism significantly. Phosphorylation of serine 264 in mouse TRESK was required for the binding of 14-3-3eta. Because 14-3-3 proteins are ubiquitous, they are expected to control the duration of calcineurin-mediated TRESK activation in all the cell types that express the channel, depending on the phosphorylation state of serine 264. This kind of direct control of channel regulation by 14-3-3 is unique within the two-pore domain K(+) channel family.
Collapse
Affiliation(s)
| | | | - Péter Enyedi
- Department of Physiology, Semmelweis University, H-1444 Budapest,
Hungary
| |
Collapse
|
114
|
Kang D, Kim GT, Kim EJ, La JH, Lee JS, Lee ES, Park JY, Hong SG, Han J. Lamotrigine inhibits TRESK regulated by G-protein coupled receptor agonists. Biochem Biophys Res Commun 2008; 367:609-15. [PMID: 18190784 DOI: 10.1016/j.bbrc.2008.01.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2007] [Accepted: 01/03/2008] [Indexed: 10/22/2022]
Abstract
Dorsal root ganglion (DRG) neurons express mRNAs for numerous two-pore domain K(+) (K(2P)) channels and G-protein coupled receptors (GPCR). Recent studies have shown that TRESK is a major background K(+) channel in DRG neurons. Here, we demonstrate the pharmacological properties of TRESK, including GPCR agonist-induced effects on DRG neurons. TRESK mRNA was highly expressed in DRG compared to brain and spinal cord. Similar to cloned TRESK, native TRESK was inhibited by acid and arachidonic acid (AA), but not zinc. Native TRESK was also activated by GPCR agonists such as acetylcholine, glutamate, and histamine. The glutamate-activated TRESK was blocked by lamotrigine in DRG neurons. In COS-7 cells transfected with mouse TRESK, 30 microM lamotrigine inhibited TRESK by approximately 50%. Since TRESK is target of modulation by acid, AA, GPCR agonists, and lamotrigine, it is likely to play an active role in the regulation of excitability in DRG neurons.
Collapse
Affiliation(s)
- Dawon Kang
- Medical Research Center for Neural Dysfunction and Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, 90 Chilam, Jinju 660-751, South Korea
| | | | | | | | | | | | | | | | | |
Collapse
|