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Journal articles on the topic 'Kv3.3'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Schwalbe, Ruth A., Melissa J. Corey, and Tara A. Cartwright. "Novel Kv3 glycoforms differentially expressed in adult mammalian brain contain sialylated N-glycans." Biochemistry and Cell Biology 86, no. 1 (February 2008): 21–30. http://dx.doi.org/10.1139/o07-152.

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The N-glycan pool of mammalian brain contains remarkably high levels of sialylated N-glycans. This study provides the first evidence that voltage-gated K+ channels Kv3.1, Kv3.3, and Kv3.4, possess distinct sialylated N-glycan structures throughout the central nervous system of the adult rat. Electrophoretic migration patterns of Kv3.1, Kv3.3, and Kv3.4 glycoproteins from spinal cord, hypothalamus, thalamus, cerebral cortex, hippocampus, and cerebellum membranes digested with glycosidases were used to identify the various glycoforms. Differences in the migration of Kv3 proteins were attributed to the desialylated N-glycans. Expression levels of the Kv3 proteins were highest in cerebellum, whereas those of Kv3.1 and Kv3.3 were much lower in the other 5 regions. The lowest level of Kv3.1 was expressed in the hypothalamus, whereas the lowest levels of Kv3.3 were expressed in both thalamus and hypothalamus. The other regions expressed intermediate levels of Kv3.3, with spinal cord expressing the highest. The expression level of Kv3.4 in the hippocampus was slightly lower than that in cerebellum, and was closely followed by the other 4 regions, with spinal cord expressing the lowest level. We suggest that novel Kv3 glycoforms may endow differences in channel function and expression among regions throughout the central nervous system.

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2

Xu, Chuanli, Yanjie Lu, Guanghua Tang, and Rui Wang. "Expression of voltage-dependent K+ channel genes in mesenteric artery smooth muscle cells." American Journal of Physiology-Gastrointestinal and Liver Physiology 277, no. 5 (November 1, 1999): G1055—G1063. http://dx.doi.org/10.1152/ajpgi.1999.277.5.g1055.

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Molecular basis of native voltage-dependent K+(Kv) channels in smooth muscle cells (SMCs) from rat mesenteric arteries was investigated. The whole cell patch-clamp study revealed that a 4-aminopyridine-sensitive delayed rectifier K+ current ( I K) was the predominant K+ conductance in these cells. A systematic screening of the expression of 18 Kv channel genes using RT-PCR technique showed that six I K-encoding genes (Kv1.2, Kv1.3, Kv1.5, Kv2.1, Kv2.2, and Kv3.2) were expressed in mesenteric artery. Although no transient outward Kv currents ( I A) were recorded in the studied SMCs, transcripts of multiple I A-encoding genes, including Kv1.4, Kv3.3, Kv3.4, Kv4.1, Kv4.2, and Kv4.3 as well as I A-facilitating Kv β-subunits (Kvβ1, Kvβ2, and Kvβ3), were detected in mesenteric arteries. Western blot analysis demonstrated that four I K-related Kv channel proteins (Kv1.2, Kv1.3, Kv1.5, and Kv2.1) were detected in mesenteric artery tissues. The presence of Kv1.2, Kv1.3, Kv1.5, and Kv2.1 channel proteins in isolated SMCs was further confirmed by immunocytochemistry study. Our results suggest that the native I K in rat mesenteric artery SMCs might be generated by heteromultimerization of Kv genes.

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3

Paucar, Martin, Richard Ågren, Tianyi Li, Simon Lissmats, Åsa Bergendal, Jan Weinberg, Daniel Nilsson, et al. "V374A KCND3 Pathogenic Variant Associated With Paroxysmal Ataxia Exacerbations." Neurology Genetics 7, no. 1 (January 6, 2021): e546. http://dx.doi.org/10.1212/nxg.0000000000000546.

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ObjectiveAtaxia channelopathies share common features such as slow motor progression and variable degrees of cognitive dysfunction. Mutations in potassium voltage-gated channel subfamily D member 3 (KCND3), encoding the K+ channel, Kv4.3, are associated with spinocerebellar ataxia (SCA) 19, allelic with SCA22. Mutations in potassium voltage-gated channel subfamily C member 3 (KCNC3), encoding another K+ channel, Kv3.3, cause SCA13. First, a comprehensive phenotype assessment was carried out in a family with autosomal dominant ataxia harboring 2 genetic variants in KCNC3 and KCND3. To evaluate the physiological impact of these variants on channel currents, in vitro studies were performed.MethodsClinical and psychometric evaluations, neuroimaging, and genotyping of a family (mother and son) affected by ataxia were carried out. Heterozygous and homozygous Kv3.3 A671V and Kv4.3 V374A variants were evaluated in Xenopus laevis oocytes using 2-electrode voltage-clamp. The influence of Kv4 conductance on neuronal activity was investigated computationally using a Purkinje neuron model.ResultsThe main clinical findings were consistent with adult-onset ataxia with cognitive dysfunction and acetazolamide-responsive paroxysmal motor exacerbations in the index case. Despite cognitive deficits, fluorodeoxyglucose (FDG)-PET displayed hypometabolism mainly in the severely atrophic cerebellum. Genetic analyses revealed the new variant c.1121T>C (V374A) in KCND3 and c.2012T>C (A671V) in KCNC3. In vitro electrophysiology experiments on Xenopus oocytes demonstrated that the V374A mutant was nonfunctional when expressed on its own. Upon equal co-expression of wild-type (WT) and V374A channel subunits, Kv4.3 currents were significantly reduced in a dominant negative manner, without alterations of the gating properties of the channel. By contrast, Kv3.3 A671V, when expressed alone, exhibited moderately reduced currents compared with WT, with no effects on channel activation or inactivation. Immunohistochemistry demonstrated adequate cell membrane translocation of the Kv4.3 V374A variant, thus suggesting an impairment of channel function, rather than of expression. Computational modeling predicted an increased Purkinje neuron firing frequency upon reduced Kv4.3 conductance.ConclusionsOur findings suggest that Kv4.3 V374A is likely pathogenic and associated with paroxysmal ataxia exacerbations, a new trait for SCA19/22. The present FDG PET findings contrast with a previous study demonstrating widespread brain hypometabolism in SCA19/22.

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4

Zagha, Edward, Satoshi Manita, William N. Ross, and Bernardo Rudy. "Dendritic Kv3.3 Potassium Channels in Cerebellar Purkinje Cells Regulate Generation and Spatial Dynamics of Dendritic Ca2+ Spikes." Journal of Neurophysiology 103, no. 6 (June 2010): 3516–25. http://dx.doi.org/10.1152/jn.00982.2009.

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Purkinje cell dendrites are excitable structures with intrinsic and synaptic conductances contributing to the generation and propagation of electrical activity. Voltage-gated potassium channel subunit Kv3.3 is expressed in the distal dendrites of Purkinje cells. However, the functional relevance of this dendritic distribution is not understood. Moreover, mutations in Kv3.3 cause movement disorders in mice and cerebellar atrophy and ataxia in humans, emphasizing the importance of understanding the role of these channels. In this study, we explore functional implications of this dendritic channel expression and compare Purkinje cell dendritic excitability in wild-type and Kv3.3 knockout mice. We demonstrate enhanced excitability of Purkinje cell dendrites in Kv3.3 knockout mice, despite normal resting membrane properties. Combined data from local application pharmacology, voltage clamp analysis of ionic currents, and assessment of dendritic Ca2+ spike threshold in Purkinje cells suggest a role for Kv3.3 channels in opposing Ca2+ spike initiation. To study the physiological relevance of altered dendritic excitability, we measured [Ca2+]i changes throughout the dendritic tree in response to climbing fiber activation. Ca2+ signals were specifically enhanced in distal dendrites of Kv3.3 knockout Purkinje cells, suggesting a role for dendritic Kv3.3 channels in regulating propagation of electrical activity and Ca2+ influx in distal dendrites. These findings characterize unique roles of Kv3.3 channels in dendrites, with implications for synaptic integration, plasticity, and human disease.

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5

Zhao, Jian, Jing Zhu, and William B. Thornhill. "Spinocerebellar ataxia-13 Kv3.3 potassium channels: arginine-to-histidine mutations affect both functional and protein expression on the cell surface." Biochemical Journal 454, no. 2 (August 9, 2013): 259–65. http://dx.doi.org/10.1042/bj20130034.

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The voltage-gated potassium channel Kv3.3 is the causative gene of SCA13 (spinocerebellar ataxia type 13), an autosomal dominant neurological disorder. The four dominant mutations identified to date cause Kv3.3 channels to be non-functional or have altered gating properties in Xenopus oocytes. In the present paper, we report that SCA13 mutations affect functional as well as protein expression of Kv3.3 channels in a mammalian cell line. The reduced protein level of SCA13 mutants is caused by a shorter protein half-life, and blocking the ubiquitin–proteasome pathway increases the total protein of SCA13 mutants more than wild-type. SCA13 mutated amino acids are highly conserved, and the side chains of these residues play a critical role in the stable expression of Kv3.3 proteins. In addition, we show that mutant Kv3.3 protein levels could be partially rescued by treatment with the chemical chaperone TMAO (trimethylamine N-oxide) and to a lesser extent with co-expression of Kv3.1b. Thus our results suggest that amino acid side chains of SCA13 positions affect the protein half-life and/or function of Kv3.3, and the adverse effect on protein expression cannot be fully rescued.

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6

Epperson, Anne, Helena P. Bonner, Sean M. Ward, William J. Hatton, Karri K. Bradley, Michael E. Bradley, James S. Trimmer, and Burton Horowitz. "Molecular diversity of KVα- and β-subunit expression in canine gastrointestinal smooth muscles." American Journal of Physiology-Gastrointestinal and Liver Physiology 277, no. 1 (July 1, 1999): G127—G136. http://dx.doi.org/10.1152/ajpgi.1999.277.1.g127.

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Voltage-activated K+(KV) channels play an important role in regulating the membrane potential in excitable cells. In gastrointestinal (GI) smooth muscles, these channels are particularly important in modulating spontaneous electrical activities. The purpose of this study was to identify the molecular components that may be responsible for the KV currents found in the canine GI tract. In this report, we have examined the qualitative expression of eighteen different KV channel genes in canine GI smooth muscle cells at the transcriptional level using RT-PCR analysis. Our results demonstrate the expression of KV1.4, KV1.5, KV1.6, KV2.2, and KV4.3 transcripts in all regions of the GI tract examined. Transcripts encoding KV1.2, KVβ1.1, and KVβ1.2 subunits were differentially expressed. KV1.1, KV1.3, KV2.1, KV3.1, KV3.2, KV3.4, KV4.1, KV4.2, and KVβ2.1 transcripts were not detected in any GI smooth muscle cells. We have also determined the protein expression for a subset of these KV channel subunits using specific antibodies by immunoblotting and immunohistochemistry. Immunoblotting and immunohistochemistry demonstrated that KV1.2, KV1.4, KV1.5, and KV2.2 are expressed at the protein level in GI tissues and smooth muscle cells. KV2.1 was not detected in any regions of the GI tract examined. These results suggest that the wide array of electrical activity found in different regions of the canine GI tract may be due in part to the differential expression of KV channel subunits.

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7

Platoshyn, Oleksandr, Carmelle V. Remillard, Ivana Fantozzi, Mehran Mandegar, Tiffany T. Sison, Shen Zhang, Elyssa Burg, and Jason X. J. Yuan. "Diversity of voltage-dependent K+ channels in human pulmonary artery smooth muscle cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 287, no. 1 (July 2004): L226—L238. http://dx.doi.org/10.1152/ajplung.00438.2003.

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Electrical excitability, which plays an important role in excitation-contraction coupling in the pulmonary vasculature, is regulated by transmembrane ion flux in pulmonary artery smooth muscle cells (PASMC). This study examined the heterogeneous nature of native voltage-dependent K+ channels in human PASMC. Both voltage-gated K+ (KV) currents and Ca2+-activated K+ (KCa) currents were observed and characterized. In cell-attached patches of PASMC bathed in Ca2+-containing solutions, depolarization elicited a wide range of K+ unitary conductances (6–290 pS). When cells were dialyzed with Ca2+-free and K+-containing solutions, depolarization elicited four components of KV currents in PASMC based on the kinetics of current activation and inactivation. Using RT-PCR, we detected transcripts of 1) 22 KV channel α-subunits (KV1.1–1.7, KV1.10, KV2.1, KV3.1, KV3.3–3.4, KV4.1–4.2, KV5.1, KV 6.1–6.3, KV9.1, KV9.3, KV10.1, and KV11.1), 2) three KV channel β-subunits (KVβ1–3), 3) four KCa channel α-subunits ( Slo-α1 and SK2–SK4), and 4) four KCa channel β-subunits (KCaβ1–4). Our results show that human PASMC exhibit a variety of voltage-dependent K+ currents with variable kinetics and conductances, which may result from various unique combinations of α- and β-subunits forming the native channels. Functional expression of these channels plays a critical role in the regulation of membrane potential, cytoplasmic Ca2+, and pulmonary vasomotor tone.

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8

Zhang, Yalan, and Leonard K. Kaczmarek. "Kv3.3 potassium channels and spinocerebellar ataxia." Journal of Physiology 594, no. 16 (November 15, 2015): 4677–84. http://dx.doi.org/10.1113/jp271343.

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9

Ghanshani, Sanjiv, Michael Pak, John D. McPherson, Michael Strong, Brent Dethlefs, John J. Wasmuth, Lawrence Salkoff, George A. Gutman, and K. George Chandy. "Genomic organization, nucleotide sequence, and cellular distribution of a Shaw-related potassium channel gene, Kv3.3, and mapping of Kv3.3 and Kv3.4 to human chromosomes 19 and 1." Genomics 12, no. 2 (February 1992): 190–96. http://dx.doi.org/10.1016/0888-7543(92)90365-y.

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10

Espinosa, F., M. A. Torres-Vega, G. A. Marks, and R. H. Joho. "Ablation of Kv3.1 and Kv3.3 Potassium Channels Disrupts Thalamocortical Oscillations In Vitro and In Vivo." Journal of Neuroscience 28, no. 21 (May 21, 2008): 5570–81. http://dx.doi.org/10.1523/jneurosci.0747-08.2008.

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11

Espinosa, Felipe, Anne McMahon, Emily Chan, Scott Wang, Chi Shun Ho, Nathaniel Heintz, and Rolf H. Joho. "Alcohol Hypersensitivity, Increased Locomotion, and Spontaneous Myoclonus in Mice Lacking the Potassium Channels Kv3.1 and Kv3.3." Journal of Neuroscience 21, no. 17 (September 1, 2001): 6657–65. http://dx.doi.org/10.1523/jneurosci.21-17-06657.2001.

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12

Lee, So Yeong, Peter J. Maniak, David H. Ingbar, and Scott M. O'Grady. "Adult alveolar epithelial cells express multiple subtypes of voltage-gated K+ channels that are located in apical membrane." American Journal of Physiology-Cell Physiology 284, no. 6 (June 1, 2003): C1614—C1624. http://dx.doi.org/10.1152/ajpcell.00429.2002.

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Whole cell perforated patch-clamp experiments were performed with adult rat alveolar epithelial cells. The holding potential was −60 mV, and depolarizing voltage steps activated voltage-gated K+ (Kv) channels. The voltage-activated currents exhibited a mean reversal potential of −32 mV. Complete activation was achieved at −10 mV. The currents exhibited slow inactivation, with significant variability in the time course between cells. Tail current analysis revealed cell-to-cell variability in K+ selectivity, suggesting contributions of multiple Kv α-subunits to the whole cell current. The Kv channels also displayed steady-state inactivation when the membrane potential was held at depolarized voltages with a window current between −30 and 5 mV. Analysis of RNA isolated from these cells by RT-PCR revealed the presence of eight Kv α-subunits (Kv1.1, Kv1.3, Kv1.4, Kv2.2, Kv4.1, Kv4.2, Kv4.3, and Kv9.3), three β-subunits (Kvβ1.1, Kvβ2.1, and Kvβ3.1), and two K+ channel interacting protein (KChIP) isoforms (KChIP2 and KChIP3). Western blot analysis with available Kv α-subunit antibodies (Kv1.1, Kv1.3, Kv1.4, Kv4.2, and Kv4.3) showed labeling of 50-kDa proteins from alveolar epithelial cells grown in monolayer culture. Immunocytochemical analysis of cells from monolayers showed that Kv1.1, Kv1.3, Kv1.4, Kv4.2, and Kv4.3 were localized to the apical membrane. We conclude that expression of multiple Kv α-, β-, and KChIP subunits explains the variability in inactivation gating and K+ selectivity observed between cells and that Kv channels in the apical membrane may contribute to basal K+ secretion across the alveolar epithelium.

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13

Desai, Rooma, Jack Kronengold, Jianfeng Mei, Stuart A. Forman, and Leonard K. Kaczmarek. "Protein Kinase C Modulates Inactivation of Kv3.3 Channels." Journal of Biological Chemistry 283, no. 32 (June 6, 2008): 22283–94. http://dx.doi.org/10.1074/jbc.m801663200.

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14

Fernandez, Fernando R., Ezequiel Morales, Asim J. Rashid, Robert J. Dunn, and Ray W. Turner. "Inactivation of Kv3.3 Potassium Channels in Heterologous Expression Systems." Journal of Biological Chemistry 278, no. 42 (August 15, 2003): 40890–98. http://dx.doi.org/10.1074/jbc.m304235200.

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15

Deng, Q. "A C-Terminal Domain Directs Kv3.3 Channels to Dendrites." Journal of Neuroscience 25, no. 50 (December 14, 2005): 11531–41. http://dx.doi.org/10.1523/jneurosci.3672-05.2005.

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16

RAE, JAMES L., and ALLAN R. SHEPARD. "Kv3.3 Potassium Channels in Lens Epithelium and Corneal Endothelium." Experimental Eye Research 70, no. 3 (March 2000): 339–48. http://dx.doi.org/10.1006/exer.1999.0796.

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17

McMahon, Anne, Stephen C. Fowler, Teresa M. Perney, Walther Akemann, Thomas Knöpfel, and Rolf H. Joho. "Allele-dependent changes of olivocerebellar circuit properties in the absence of the voltage-gated potassium channels Kv3.1 and Kv3.3." European Journal of Neuroscience 19, no. 12 (June 2004): 3317–27. http://dx.doi.org/10.1111/j.0953-816x.2004.03385.x.

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18

Choudhury, Nasreen, Deborah Linley, Amy Richardson, Michelle Anderson, Susan W. Robinson, Vincenzo Marra, Victoria Ciampani, et al. "Kv3.1 and Kv3.3 subunits differentially contribute to Kv3 channels and action potential repolarization in principal neurons of the auditory brainstem." Journal of Physiology 598, no. 11 (May 16, 2020): 2199–222. http://dx.doi.org/10.1113/jp279668.

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19

Hernández-Pineda, R., A. Chow, Y. Amarillo, H. Moreno, M. Saganich, E. Vega-Saenz de Miera, A. Hernández-Cruz, and B. Rudy. "Kv3.1–Kv3.2 Channels Underlie a High-Voltage–Activating Component of the Delayed Rectifier K+ Current in Projecting Neurons From the Globus Pallidus." Journal of Neurophysiology 82, no. 3 (September 1, 1999): 1512–28. http://dx.doi.org/10.1152/jn.1999.82.3.1512.

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The globus pallidus plays central roles in the basal ganglia circuitry involved in movement control as well as in cognitive and emotional functions. There is therefore great interest in the anatomic and electrophysiological characterization of this nucleus. Most pallidal neurons are GABAergic projecting cells, a large fraction of which express the calcium binding protein parvalbumin (PV). Here we show that PV-containing pallidal neurons coexpress Kv3.1 and Kv3.2 K+ channel proteins and that both Kv3.1 and Kv3.2 antibodies coprecipitate both channel proteins from pallidal membrane extracts solubilized with nondenaturing detergents, suggesting that the two channel subunits are forming heteromeric channels. Kv3.1 and Kv3.2 channels have several unusual electrophysiological properties when expressed in heterologous expression systems and are thought to play special roles in neuronal excitability including facilitating sustained high-frequency firing in fast-spiking neurons such as interneurons in the cortex and the hippocampus. Electrophysiological analysis of freshly dissociated pallidal neurons demonstrates that these cells have a current that is nearly identical to the currents expressed by Kv3.1 and Kv3.2 proteins in heterologous expression systems, including activation at very depolarized membrane potentials (more positive than −10 mV) and very fast deactivation rates. These results suggest that the electrophysiological properties of native channels containing Kv3.1 and Kv3.2 proteins in pallidal neurons are not significantly affected by factors such as associated subunits or postranslational modifications that result in channels having different properties in heterologous expression systems and native neurons. Most neurons in the globus pallidus have been reported to fire sustained trains of action potentials at high-frequency. Kv3.1–Kv3.2 voltage-gated K+channels may play a role in helping maintain sustained high-frequency repetitive firing as they probably do in other neurons.

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20

Minassian, Natali A., Meng-Chin A. Lin, and Diane M. Papazian. "Altered Kv3.3 channel gating in early-onset spinocerebellar ataxia type 13." Journal of Physiology 590, no. 7 (March 14, 2012): 1599–614. http://dx.doi.org/10.1113/jphysiol.2012.228205.

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21

Matsukawa, Hiroshi, Alexander M. Wolf, Shinichi Matsushita, Rolf H. Joho, and Thomas Knöpfel. "Motor Dysfunction and Altered Synaptic Transmission at the Parallel Fiber-Purkinje Cell Synapse in Mice Lacking Potassium Channels Kv3.1 and Kv3.3." Journal of Neuroscience 23, no. 20 (August 20, 2003): 7677–84. http://dx.doi.org/10.1523/jneurosci.23-20-07677.2003.

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22

Erisir, A., D. Lau, B. Rudy, and C. S. Leonard. "Function of Specific K+ Channels in Sustained High-Frequency Firing of Fast-Spiking Neocortical Interneurons." Journal of Neurophysiology 82, no. 5 (November 1, 1999): 2476–89. http://dx.doi.org/10.1152/jn.1999.82.5.2476.

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Fast-spiking GABAergic interneurons of the neocortex and hippocampus fire high-frequency trains of brief action potentials with little spike-frequency adaptation. How these striking properties arise is unclear, although recent evidence suggests K+ channels containing Kv3.1-Kv3.2 proteins play an important role. We investigated the role of these channels in the firing properties of fast-spiking neocortical interneurons from mouse somatosensory cortex using a pharmacological and modeling approach. Low tetraethylammonium (TEA) concentrations (≤1 mM), which block only a few known K+channels including Kv3.1-Kv3.2, profoundly impaired action potential repolarization and high-frequency firing. Analysis of the spike trains evoked by steady depolarization revealed that, although TEA had little effect on the initial firing rate, it strongly reduced firing frequency later in the trains. These effects appeared to be specific to Kv3.1 and Kv3.2 channels, because blockade of dendrotoxin-sensitive Kv1 channels and BK Ca2+-activated K+ channels, which also have high TEA sensitivity, produced opposite or no effects. Voltage-clamp experiments confirmed the presence of a Kv3.1-Kv3.2–like current in fast-spiking neurons, but not in other interneurons. Analysis of spike shape changes during the spike trains suggested that Na+ channel inactivation plays a significant role in the firing-rate slowdown produced by TEA, a conclusion that was supported by computer simulations. These findings indicate that the unique properties of Kv3.1-Kv3.2 channels enable sustained high-frequency firing by facilitating the recovery of Na+ channel inactivation and by minimizing the duration of the afterhyperpolarization in neocortical interneurons.

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23

Wang, Jian, Letitia Weigand, Wenqian Wang, J. T. Sylvester, and Larissa A. Shimoda. "Chronic hypoxia inhibits Kv channel gene expression in rat distal pulmonary artery." American Journal of Physiology-Lung Cellular and Molecular Physiology 288, no. 6 (June 2005): L1049—L1058. http://dx.doi.org/10.1152/ajplung.00379.2004.

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In pulmonary arterial smooth muscle cells (PASMCs), voltage-gated K+ (Kv) channels play an important role in regulating membrane potential, cytoplasmic free Ca2+ concentration, and pulmonary vasomotor tone. Previous studies demonstrated that exposure of rats to chronic hypoxia decreased Kv channel function in PASMCs from distal pulmonary arteries (dPA). To determine whether this decrease in function was due to decreased expression of Kv channel proteins and which Kv proteins might be involved, we analyzed Kv channel gene expression in intact, endothelium-denuded dPAs obtained from rats exposed to 10% O2 for 3 wk. Kv1.1, Kv1.2, Kv1.4, Kv1.5, Kv1.6, Kv2.1, Kv3.1, Kv4.3, and Kv9.3 channel α-subunits and Kv1, Kv2, and Kv3 β-subunits were expressed in rat dPAs. Exposure to chronic hypoxia decreased mRNA and protein levels of Kv1.1, Kv1.5, Kv1.6, Kv2.1, and Kv4.3 α-subunits in dPAs but did not alter gene or protein expression of these channels in aorta. Furthermore, chronic hypoxia did not alter the mRNA levels of β-subunits in dPAs. These results suggest that diminished transcription of Kv α-subunits may reduce the number of functional Kv channels in dPAs during prolonged hypoxia, causing the decreased Kv current previously observed in PASMCs and leading to pulmonary artery vasoconstriction.

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24

Song, Min Seok, Seon Young Choi, Pan Dong Ryu, and So Yeong Lee. "Voltage-Gated K+ Channel, Kv3.3 Is Involved in Hemin-Induced K562 Differentiation." PLOS ONE 11, no. 2 (February 5, 2016): e0148633. http://dx.doi.org/10.1371/journal.pone.0148633.

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25

Minassian, Natali A., Meng-chin Lin, Karla P. Figueroa, Allan F. Mock, Giovanni Stevanin, Michael F. Waters, Stefan M. Pulst, and Diane M. Papazian. "Distinct Functional Effects of Kv3.3 Mutations Associated with Spinocerebellar Ataxia Type 13." Biophysical Journal 96, no. 3 (February 2009): 328a. http://dx.doi.org/10.1016/j.bpj.2008.12.1652.

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26

Kuryshev, Yuri A., Tatyana I. Gudz, Arthur M. Brown, and Barbara A. Wible. "KChAP as a chaperone for specific K+channels." American Journal of Physiology-Cell Physiology 278, no. 5 (May 1, 2000): C931—C941. http://dx.doi.org/10.1152/ajpcell.2000.278.5.c931.

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The concept of chaperones for K+ channels is new. Recently, we discovered a novel molecular chaperone, KChAP, which increased total Kv2.1 protein and functional channels in Xenopus oocytes through a transient interaction with the Kv2.1 amino terminus. Here we report that KChAP is a chaperone for Kv1.3 and Kv4.3. KChAP increased the amplitude of Kv1.3 and Kv4.3 currents without affecting kinetics or voltage dependence, but had no such effect on Kv1.1, 1.2, 1.4, 1.5, 1.6, and 3.1 or Kir2.2, HERG, or KvLQT1. Although KChAP belongs to a family of proteins that interact with transcription factors, upregulation of channel currents was not blocked by the transcription inhibitor actinomycin D. A 98-amino acid fragment of KChAP binds to the channel and is indistinguishable from KChAP in its enhancement of Kv4.3 current and protein levels. Using a KChAP antibody, we have coimmunoprecipitated KChAP with Kv2.1 and Kv4.3 from heart. We propose that KChAP is a chaperone for specific Kv channels and may have this function in cardiomyocytes where Kv4.3 produces the transient outward current, I to.

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27

Brooke, Ruth Elizabeth, Laura Corns, Ian James Edwards, and Jim Deuchars. "Kv3.3 immunoreactivity in the vestibular nuclear complex of the rat with focus on the medial vestibular nucleus: Targeting of Kv3.3 neurones by terminals positive for vesicular glutamate transporter 1." Brain Research 1345 (July 2010): 45–58. http://dx.doi.org/10.1016/j.brainres.2010.05.020.

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Nowak, A., H. R. Mathieson, R. J. Chapman, G. Janzsó, Y. Yanagawa, K. Obata, G. Szabo, and A. E. King. "Kv3.1b and Kv3.3 channel subunit expression in murine spinal dorsal horn GABAergic interneurones." Journal of Chemical Neuroanatomy 42, no. 1 (September 2011): 30–38. http://dx.doi.org/10.1016/j.jchemneu.2011.02.003.

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Chang, Su Ying, Edward Zagha, Elaine S. Kwon, Andres Ozaita, Marketta Bobik, Maryann E. Martone, Mark H. Ellisman, Nathaniel Heintz, and Bernardo Rudy. "Distribution of Kv3.3 potassium channel subunits in distinct neuronal populations of mouse brain." Journal of Comparative Neurology 502, no. 6 (June 20, 2007): 953–72. http://dx.doi.org/10.1002/cne.21353.

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Porcello, Darrell M., Chi Shun Ho, Rolf H. Joho, and John R. Huguenard. "Resilient RTN Fast Spiking in Kv3.1 Null Mice Suggests Redundancy in the Action Potential Repolarization Mechanism." Journal of Neurophysiology 87, no. 3 (March 1, 2002): 1303–10. http://dx.doi.org/10.1152/jn.00556.2001.

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Fast spiking (FS), GABAergic neurons of the reticular thalamic nucleus (RTN) are capable of firing high-frequency trains of brief action potentials, with little adaptation. Studies in recombinant systems have shown that high-voltage-activated K+ channels containing the Kv3.1 and/or Kv3.2 subunits display biophysical properties that may contribute to the FS phenotype. Given that RTN expresses high levels of Kv3.1, with little or no Kv3.2, we tested whether this subunit was required for the fast action potential repolarization mechanism essential to the FS phenotype. Single- and multiple-action potentials were recorded using whole-cell current clamp in RTN neurons from brain slices of wild-type and Kv3.1-deficient mice. At 23°C, action potentials recorded from homozygous Kv3.1 deficient mice (Kv3.1−/−) compared with their wild-type (Kv3.1+/+) counterparts had reduced amplitudes (−6%) and fast after-hyperpolarizations (−16%). At 34°C, action potentials in Kv3.1−/− mice had increased duration (21%) due to a reduced rate of repolarization (−30%) when compared with wild-type controls. Action potential trains in Kv3.1−/− were associated with a significantly greater spike decrement and broadening and a diminished firing frequency versus injected current relationship ( F/I) at 34°C. There was no change in either spike count or maximum instantaneous frequency during low-threshold Ca2+ bursts in Kv3.1−/− RTN neurons at either temperature tested. Our findings show that Kv3.1 is not solely responsible for fast spikes or high-frequency firing in RTN neurons. This suggests genetic redundancy in the system, possibly in the form of other Kv3 members, which may suffice to maintain the FS phenotype in RTN neurons in the absence of Kv3.1.

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Buttigieg, Josef, Jie Pan, Herman Yeger, and Ernest Cutz. "NOX2 (gp91phox) is a predominant O2 sensor in a human airway chemoreceptor cell line: biochemical, molecular, and electrophysiological evidence." American Journal of Physiology-Lung Cellular and Molecular Physiology 303, no. 7 (October 1, 2012): L598—L607. http://dx.doi.org/10.1152/ajplung.00170.2012.

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Pulmonary neuroepithelial bodies (NEBs), composed of clusters of amine [serotonin (5-HT)] and peptide-producing cells, are widely distributed within the airway mucosa of human and animal lungs. NEBs are thought to function as airway O2-sensors, since they are extensively innervated and release 5-HT upon hypoxia exposure. The small cell lung carcinoma cell line (H146) provides a useful model for native NEBs, since they contain (and secrete) 5-HT and share the expression of a membrane-delimited O2 sensor [classical NADPH oxidase (NOX2) coupled to an O2-sensitive K+ channel]. In addition, both native NEBs and H146 cells express different NADPH oxidase homologs (NOX1, NOX4) and its subunits together with a variety of O2-sensitive voltage-dependent K+ channel proteins (Kv) and tandem pore acid-sensing K+ channels (TASK). Here we used H146 cells to investigate the role and interactions of various NADPH oxidase components in O2-sensing using a combination of coimmunoprecipitation, Western blot analysis (quantum dot labeling), and electrophysiology (patchclamp, amperometry) methods. Coimmunoprecipitation studies demonstrated formation of molecular complexes between NOX2 and Kv3.3 and Kv4.3 ion channels but not with TASK1 ion channels, while NOX4 associated with TASK1 but not with Kv channel proteins. Downregulation of mRNA for NOX2, but not for NOX4, suppressed hypoxia-sensitive outward current and significantly reduced hypoxia -induced 5-HT release. Collectively, our studies suggest that NOX2/Kv complexes are the predominant O2 sensor in H146 cells and, by inference, in native NEBs. Present findings favor a NEB cell-specific plasma membrane model of O2-sensing and suggest that unique NOX/K+ channel combinations may serve diverse physiological functions.

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Aiyar, J., S. Grissmer, and K. G. Chandy. "Full-length and truncated Kv1.3 K+ channels are modulated by 5-HT1c receptor activation and independently by PKC." American Journal of Physiology-Cell Physiology 265, no. 6 (December 1, 1993): C1571—C1578. http://dx.doi.org/10.1152/ajpcell.1993.265.6.c1571.

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In T-cells, the Shaker-related gene, Kv1.3 encodes the type n K+ channel, whereas the type l channel is a product of the Shaw. subfamily gene, Kv3.1. Both these genes are also expressed in the brain. We have used the Xenopus oocyte heterologous expression system to study the modulatory effects of serotonin (5-hydroxytryptamine, 5-HT) on both these cloned channels. In oocytes coexpressing the mouse 5-HT1c receptor and mouse Kv1.3 channel, addition of 100 nM 5-HT causes a complete and sustained suppression of Kv1.3 currents in approximately 20 min. In contrast, 5-HT has no effect on mouse Kv3.1 currents when coexpressed with 5-HT1c receptor. The 5-HT-mediated suppression of Kv1.3 currents proceeds via activation of a pertussis toxin-sensitive G protein and a subsequent rise in intracellular Ca2+, but Ca2+ does not directly block the channel. Protein kinase (PK) C activation is not part of the pathway linking 5-HT1c receptor to Kv1.3 channels. However, phorbol esters independently suppress Kv1.3 currents. Deletion of the first 146 amino acids from the NH2-terminal, containing putative tyrosine kinase and PKA phosphorylation sites, does not alter the time course of 5-HT-mediated suppression of Kv1.3 currents, indicating that these residues are not necessary for modulation. Treatment of oocytes with calmodulin or phosphatase inhibitors does not alter 5-HT-mediated modulation. Collectively, these experiments indicate that the mouse Kv1.3 channel is capable of being modulated by 5-HT via 5-HT1c receptor in a G protein and Ca(2+)-dependent manner, but the subsequent steps in the pathway remain elusive.(ABSTRACT TRUNCATED AT 250 WORDS)

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Mock, Allan F., Jessica L. Richardson, Jui-Yi Hsieh, Gina Rinetti, and Diane M. Papazian. "Functional effects of spinocerebellar ataxia type 13 mutations are conserved in zebrafish Kv3.3 channels." BMC Neuroscience 11, no. 1 (2010): 99. http://dx.doi.org/10.1186/1471-2202-11-99.

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Rashid, Asim J., Robert J. Dunn, and Ray W. Turner. "A prominent soma-dendritic distribution of Kv3.3 K+ channels in electrosensory and cerebellar neurons." Journal of Comparative Neurology 441, no. 3 (2001): 234–47. http://dx.doi.org/10.1002/cne.1409.

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35

Zhang, Yalan, Luis Varela, Klara Szigeti-Buck, Tamas L. Horvath, and Leonard K. Kaczmarek. "Loss of HAX-1 May Contribute to the Neurodegeneration Caused by a Kv3.3 Mutation." Biophysical Journal 116, no. 3 (February 2019): 104a. http://dx.doi.org/10.1016/j.bpj.2018.11.596.

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Nomura, Masaki, Tomoki Fukai, and Toshio Aoyagi. "Synchrony of Fast-Spiking Interneurons Interconnected by GABAergic and Electrical Synapses." Neural Computation 15, no. 9 (September 1, 2003): 2179–98. http://dx.doi.org/10.1162/089976603322297340.

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Fast-spiking (FS) interneurons have specific types (Kv3.1/3.2 type) of the delayed potassium channel, which differ from the conventional Hodgkin-Huxley (HH) type potassium channel (Kv1.3 type) in several aspects. In this study, we show dramatic effects of the Kv3.1/3.2 potassium channel on the synchronization of the FS interneurons. We show analytically that two identical electrically coupled FS interneurons modeled with Kv3.1/3.2 channel fire synchronously at arbitrary firing frequencies, unlike similarly coupled FS neurons modeled with Kv1.3 channel that show frequency-dependent synchronous and antisynchronous firing states. Introducing GABA A receptor-mediated synaptic connections into an FS neuron pair tends to induce an antisynchronous firing state, even if the chemical synapses are bidirectional. Accordingly, an FS neuron pair connected simultaneously by electrical and chemical synapses achieves both synchronous firing state and antisynchronous firing state in a physiologically plausible range of the conductance ratio between electrical and chemical synapses. Moreover, we find that a large-scale network of FS interneurons connected by gap junctions and bidirectional GABAergic synapses shows similar bistability in the range of gamma frequencies (30–70 Hz).

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Kim, Sung Eun, Hye Sook Ahn, Bok Hee Choi, Hyun-Jong Jang, Myung-Jun Kim, Duck-Joo Rhie, Shin-Hee Yoon, et al. "Open Channel Block of A-Type, Kv4.3, and Delayed Rectifier K+ Channels, Kv1.3 and Kv3.1, by Sibutramine." Journal of Pharmacology and Experimental Therapeutics 321, no. 2 (February 20, 2007): 753–62. http://dx.doi.org/10.1124/jpet.106.117747.

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38

Stevens, Sharon R., Meike E. van der Heijden, Yuki Ogawa, Tao Lin, Roy V. Sillitoe, and Matthew N. Rasband. "Ankyrin-R Links Kv3.3 to the Spectrin Cytoskeleton and Is Required for Purkinje Neuron Survival." Journal of Neuroscience 42, no. 1 (November 16, 2021): 2–15. http://dx.doi.org/10.1523/jneurosci.1132-21.2021.

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39

Middlebrooks, John C., Harry S. Nick, S. H. Subramony, Joel Advincula, Raymond L. Rosales, Lillian V. Lee, Tetsuo Ashizawa, and Michael F. Waters. "Mutation in the Kv3.3 Voltage-Gated Potassium Channel Causing Spinocerebellar Ataxia 13 Disrupts Sound-Localization Mechanisms." PLoS ONE 8, no. 10 (October 7, 2013): e76749. http://dx.doi.org/10.1371/journal.pone.0076749.

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40

Kruse, Martin, Gerald R. V. Hammond, and Bertil Hille. "Regulation of voltage-gated potassium channels by PI(4,5)P2." Journal of General Physiology 140, no. 2 (July 30, 2012): 189–205. http://dx.doi.org/10.1085/jgp.201210806.

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Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) regulates activities of numerous ion channels including inwardly rectifying potassium (Kir) channels, KCNQ, TRP, and voltage-gated calcium channels. Several studies suggest that voltage-gated potassium (KV) channels might be regulated by PI(4,5)P2. Wide expression of KV channels in different cells suggests that such regulation could have broad physiological consequences. To study regulation of KV channels by PI(4,5)P2, we have coexpressed several of them in tsA-201 cells with a G protein–coupled receptor (M1R), a voltage-sensitive lipid 5-phosphatase (Dr-VSP), or an engineered fusion protein carrying both lipid 4-phosphatase and 5-phosphatase activity (pseudojanin). These tools deplete PI(4,5)P2 with application of muscarinic agonists, depolarization, or rapamycin, respectively. PI(4,5)P2 at the plasma membrane was monitored by Förster resonance energy transfer (FRET) from PH probes of PLCδ1 simultaneously with whole-cell recordings. Activation of Dr-VSP or recruitment of pseudojanin inhibited KV7.1, KV7.2/7.3, and Kir2.1 channel current by 90–95%. Activation of M1R inhibited KV7.2/7.3 current similarly. With these tools, we tested for potential PI(4,5)P2 regulation of activity of KV1.1/KVβ1.1, KV1.3, KV1.4, and KV1.5/KVβ1.3, KV2.1, KV3.4, KV4.2, KV4.3 (with different KChIPs and DPP6-s), and hERG/KCNE2. Interestingly, we found a substantial removal of inactivation for KV1.1/KVβ1.1 and KV3.4, resulting in up-regulation of current density upon activation of M1R but no changes in activity upon activating only VSP or pseudojanin. The other channels tested except possibly hERG showed no alteration in activity in any of the assays we used. In conclusion, a depletion of PI(4,5)P2 at the plasma membrane by enzymes does not seem to influence activity of most tested KV channels, whereas it does strongly inhibit members of the KV7 and Kir families.

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Zagha, E., E. J. Lang, and B. Rudy. "Kv3.3 Channels at the Purkinje Cell Soma Are Necessary for Generation of the Classical Complex Spike Waveform." Journal of Neuroscience 28, no. 6 (February 6, 2008): 1291–300. http://dx.doi.org/10.1523/jneurosci.4358-07.2008.

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Hurlock, E. C., A. McMahon, and R. H. Joho. "Purkinje-Cell-Restricted Restoration of Kv3.3 Function Restores Complex Spikes and Rescues Motor Coordination in Kcnc3 Mutants." Journal of Neuroscience 28, no. 18 (April 30, 2008): 4640–48. http://dx.doi.org/10.1523/jneurosci.5486-07.2008.

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Hurlock, E. C., M. Bose, G. Pierce, and R. H. Joho. "Rescue of Motor Coordination by Purkinje Cell-Targeted Restoration of Kv3.3 Channels in Kcnc3-Null Mice Requires Kcnc1." Journal of Neuroscience 29, no. 50 (December 16, 2009): 15735–44. http://dx.doi.org/10.1523/jneurosci.4048-09.2009.

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Kuryshev, Y. A., B. A. Wible, T. I. Gudz, A. N. Ramirez, and A. M. Brown. "KChAP/Kvβ1.2 interactions and their effects on cardiac Kv channel expression." American Journal of Physiology-Cell Physiology 281, no. 1 (July 1, 2001): C290—C299. http://dx.doi.org/10.1152/ajpcell.2001.281.1.c290.

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KChAP and voltage-dependent K+ (Kv) β-subunits are two different types of cytoplasmic proteins that interact with Kv channels. KChAP acts as a chaperone for Kv2.1 and Kv4.3 channels. It also binds to Kv1.x channels but, with the exception of Kv1.3, does not increase Kv1.x currents. Kvβ-subunits are assembled with Kv1.x channels; they exhibit “chaperone-like” behavior and change gating properties. In addition, KChAP and Kvβ-subunits interact with each other. Here we examine the consequences of this interaction on Kv currents in Xenopusoocytes injected with different combinations of cRNAs, including Kvβ1.2, KChAP, and either Kv1.4, Kv1.5, Kv2.1, or Kv4.3. We found that KChAP attenuated the depression of Kv1.5 currents produced by Kvβ1.2, and Kvβ1.2 eliminated the increase of Kv2.1 and Kv4.3 currents produced by KChAP. Both KChAP and Kvβ1.2 are expressed in cardiomyocytes, where Kv1.5 and Kv2.1 produce sustained outward currents and Kv4.3 and Kv1.4 generate transient outward currents. Because they interact, either KChAP or Kvβ1.2 may alter both sustained and transient cardiac Kv currents. The interaction of these two different classes of modulatory proteins may constitute a novel mechanism for regulating cardiac K+ currents.

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Ahn, Hye Sook, Sung Eun Kim, Bok Hee Choi, Jin-Sung Choi, Myung-Jun Kim, Duck-Joo Rhie, Shin Hee Yoon, et al. "Calcineurin-independent inhibition of KV1.3 by FK-506 (tacrolimus): a novel pharmacological property." American Journal of Physiology-Cell Physiology 292, no. 5 (May 2007): C1714—C1722. http://dx.doi.org/10.1152/ajpcell.00258.2006.

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The interaction of FK-506 with KV1.3, stably expressed in Chinese hamster ovary cells, was investigated with the whole cell patch-clamp technique. FK-506 inhibited KV1.3 in a reversible, concentration-dependent manner with an IC50 of 5.6 μM. Rapamycin, another immunosuppressant, produced effects that were similar to those of FK-506 (IC50 = 6.7 μM). Other calcineurin inhibitors (cypermethrin or calcineurin autoinhibitory peptide) alone had no effect on the amplitude or kinetics of KV1.3. In addition, the inhibitory action of FK-506 continued, even after the inhibition of calcineurin activity. The inhibition produced by FK-506 was voltage dependent, increasing in the voltage range for channel activation. At potentials positive to 0 mV (where maximal conductance is reached), however, no voltage-dependent inhibition was found. FK-506 exhibited a strong use-dependent inhibition of KV1.3. FK-506 shifted the steady-state inactivation curves of KV1.3 in the hyperpolarizing direction in a concentration-dependent manner. The apparent dissociation constant for FK-506 to inhibit KV1.3 in the inactivated state was estimated from the concentration-dependent shift in the steady-state inactivation curve and was calculated to be 0.37 μM. Moreover, the rate of recovery from inactivation of KV1.3 was decreased. In inside-out patches, FK-506 not only reduced the current amplitude but also accelerated the rate of inactivation during depolarization. FK-506 also inhibited KV1.5 and KV4.3 in a concentration-dependent manner with IC50 of 4.6 and 53.9 μM, respectively. The present results indicate that FK-506 inhibits KV1.3 directly and that this effect is not mediated via the inhibition of the phosphatase activity of calcineurin.

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McDaniel, Sharon S., Oleksandr Platoshyn, Ying Yu, Michele Sweeney, Victor A. Miriel, Vera A. Golovina, Stefanie Krick, Bethany R. Lapp, Jian-Ying Wang, and Jason X. J. Yuan. "Anorexic effect of K+ channel blockade in mesenteric arterial smooth muscle and intestinal epithelial cells." Journal of Applied Physiology 91, no. 5 (November 1, 2001): 2322–33. http://dx.doi.org/10.1152/jappl.2001.91.5.2322.

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Activity of voltage-gated K+ (Kv) channels controls membrane potential ( E m). Membrane depolarization due to blockade of K+ channels in mesenteric artery smooth muscle cells (MASMC) should increase cytoplasmic free Ca2+ concentration ([Ca2+]cyt) and cause vasoconstriction, which may subsequently reduce the mesenteric blood flow and inhibit the transportation of absorbed nutrients to the liver and adipose tissue. In this study, we characterized and compared the electrophysiological properties and molecular identities of Kv channels and examined the role of Kv channel function in regulating E m in MASMC and intestinal epithelial cells (IEC). MASMC and IEC functionally expressed multiple Kv channel α- and β-subunits (Kv1.1, Kv1.2, Kv1.3, Kv1.4, Kv1.5, Kv2.1, Kv4.3, and Kv9.3, as well as Kvβ1.1, Kvβ2.1, and Kvβ3), but only MASMC expressed voltage-dependent Ca2+ channels. The current density and the activation and inactivation kinetics of whole cell Kv currents were similar in MASMC and IEC. Extracellular application of 4-aminopyridine (4-AP), a Kv-channel blocker, reduced whole cell Kv currents and caused E m depolarization in both MASMC and IEC. The 4-AP-induced E m depolarization increased [Ca2+]cyt in MASMC and caused mesenteric vasoconstriction. Furthermore, ingestion of 4-AP significantly reduced the weight gain in rats. These results suggest that MASMC and IEC express multiple Kv channel α- and β-subunits. The function of these Kv channels plays an important role in controlling E m. The membrane depolarization-mediated increase in [Ca2+]cyt in MASMC and mesenteric vasoconstriction may inhibit transportation of absorbed nutrients via mesenteric circulation and limit weight gain.

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Zhang, Yalan, Xiao-Feng Zhang, Matthew R. Fleming, Anahita Amiri, Lynda El-Hassar, Alexei A. Surguchev, Callen Hyland, et al. "Kv3.3 Channels Bind Hax-1 and Arp2/3 to Assemble a Stable Local Actin Network that Regulates Channel Gating." Cell 165, no. 2 (April 2016): 434–48. http://dx.doi.org/10.1016/j.cell.2016.02.009.

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48

Kaar, Stephen J., Ilinca Angelescu, Matthew M. Nour, Tiago Reis Marques, Alice Sharman, Anil Sajjala, John Hutchison, Philip McGuire, Charles Large, and Oliver D. Howes. "The effects of AUT00206, a novel Kv3.1/3.2 potassium channel modulator, on task-based reward system activation: a test of mechanism in schizophrenia." Psychopharmacology 239, no. 10 (September 12, 2022): 3313–23. http://dx.doi.org/10.1007/s00213-022-06216-3.

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AbstractThe pathophysiology of schizophrenia involves abnormal reward processing, thought to be due to disrupted striatal and dopaminergic function. Consistent with this hypothesis, functional magnetic resonance imaging (fMRI) studies using the monetary incentive delay (MID) task report hypoactivation in the striatum during reward anticipation in schizophrenia. Dopamine neuron activity is modulated by striatal GABAergic interneurons. GABAergic interneuron firing rates, in turn, are related to conductances in voltage-gated potassium 3.1 (Kv3.1) and 3.2 (Kv3.2) channels, suggesting that targeting Kv3.1/3.2 could augment striatal function during reward processing. Here, we studied the effect of a novel potassium Kv3.1/3.2 channel modulator, AUT00206, on striatal activation in patients with schizophrenia, using the MID task. Each participant completed the MID during fMRI scanning on two occasions: once at baseline, and again following either 4 weeks of AUT00206 or placebo treatment. We found a significant inverse relationship at baseline between symptom severity and reward anticipation-related neural activation in the right associative striatum (r = -0.461, p = 0.035). Following treatment with AUT00206, there was a significant increase in reward anticipation-related activation in the left associative striatum (t(13) = 4.23, peak-level p(FWE) < 0.05)), but no significant effect in the ventral striatum. This provides preliminary evidence that the Kv3.1/3.2 potassium channel modulator, AUT00206, may address reward-related striatal abnormalities in schizophrenia.

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Brooke, Ruth E., Lucy Atkinson, Ian Edwards, Simon H. Parson, and Jim Deuchars. "Immunohistochemical localisation of the voltage gated potassium ion channel subunit Kv3.3 in the rat medulla oblongata and thoracic spinal cord." Brain Research 1070, no. 1 (January 2006): 101–15. http://dx.doi.org/10.1016/j.brainres.2005.10.102.

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Irie, Tomohiko, Yasunori Matsuzaki, Yuko Sekino, and Hirokazu Hirai. "Kv3.3 channels harbouring a mutation of spinocerebellar ataxia type 13 alter excitability and induce cell death in cultured cerebellar Purkinje cells." Journal of Physiology 592, no. 1 (December 10, 2013): 229–47. http://dx.doi.org/10.1113/jphysiol.2013.264309.

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