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The regulatory function of lncRNA and constructed network in epilepsy. Neurol Sci 2023; 44:1543-1554. [PMID: 36781564 DOI: 10.1007/s10072-023-06648-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/27/2023] [Indexed: 02/15/2023]
Abstract
BACKGROUND Epilepsy is a neurological disease characterized by neural network dysfunction. Although most reports indicate that the pathological process of epilepsy is related to inflammation, synaptic plasticity, cell apoptosis, and ion channel dysfunction, the underlying molecular mechanisms of epilepsy are not fully understood. METHODS This review summarizes the latest literature on the roles and characteristics of long noncoding RNAs (lncRNAs) in the pathogenesis of epilepsy. RESULTS lncRNAs are a class of long transcripts without protein-coding functions that perform important regulatory functions in various biological processes. lncRNAs are involved in the regulation of the pathological process of epilepsy and are abnormally expressed in both patients and animal models. This review provides an overview of research progress in epilepsy, the multifunctional features of lncRNAs, the lncRNA expression pattern related to epileptogenesis and status epilepticus, and the potential mechanisms for the two interactions contributing to epileptogenesis and progression. CONCLUSION lncRNAs can serve as new diagnostic markers and therapeutic targets for epilepsy in the future.
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Albisetti GW, Ganley RP, Pietrafesa F, Werynska K, Magalhaes de Sousa M, Sipione R, Scheurer L, Bösl MR, Pelczar P, Wildner H, Zeilhofer HU. Inhibitory Kcnip2 neurons of the spinal dorsal horn control behavioral sensitivity to environmental cold. Neuron 2023; 111:92-105.e5. [PMID: 36323322 PMCID: PMC9831669 DOI: 10.1016/j.neuron.2022.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 08/16/2022] [Accepted: 10/04/2022] [Indexed: 11/12/2022]
Abstract
Proper sensing of ambient temperature is of utmost importance for the survival of euthermic animals, including humans. While considerable progress has been made in our understanding of temperature sensors and transduction mechanisms, the higher-order neural circuits processing such information are still only incompletely understood. Using intersectional genetics in combination with circuit tracing and functional neuron manipulation, we identified Kcnip2-expressing inhibitory (Kcnip2GlyT2) interneurons of the mouse spinal dorsal horn as critical elements of a neural circuit that tunes sensitivity to cold. Diphtheria toxin-mediated ablation of these neurons increased cold sensitivity without affecting responses to other somatosensory modalities, while their chemogenetic activation reduced cold and also heat sensitivity. We also show that Kcnip2GlyT2 neurons become activated preferentially upon exposure to cold temperatures and subsequently inhibit spinal nociceptive output neurons that project to the lateral parabrachial nucleus. Our results thus identify a hitherto unknown spinal circuit that tunes cold sensitivity.
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Affiliation(s)
- Gioele W. Albisetti
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland
| | - Robert P. Ganley
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland
| | - Francesca Pietrafesa
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland
| | - Karolina Werynska
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland
| | | | - Rebecca Sipione
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland
| | - Louis Scheurer
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland
| | - Michael R. Bösl
- Institute of Experimental Biomedicine I, University Hospital Würzburg, and Rudolf Virchow Center, University of Würzburg, 97080 Würzburg, Germany
| | - Pawel Pelczar
- Center for Transgenic Models, University of Basel, 4001 Basel, Switzerland
| | - Hendrik Wildner
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland,Corresponding author
| | - Hanns Ulrich Zeilhofer
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zürich, Switzerland,Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, 8093 Zürich, Switzerland,Center for Neuroscience Zurich (ZNZ), 8057 Zürich, Switzerland,Drug Discovery Network Zurich (DDNZ), 8057 Zürich, Switzerland,Corresponding author
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Oláh VJ, Lukacsovich D, Winterer J, Arszovszki A, Lőrincz A, Nusser Z, Földy C, Szabadics J. Functional specification of CCK+ interneurons by alternative isoforms of Kv4.3 auxiliary subunits. eLife 2020; 9:58515. [PMID: 32490811 PMCID: PMC7269670 DOI: 10.7554/elife.58515] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 05/20/2020] [Indexed: 01/18/2023] Open
Abstract
CCK-expressing interneurons (CCK+INs) are crucial for controlling hippocampal activity. We found two firing phenotypes of CCK+INs in rat hippocampal CA3 area; either possessing a previously undetected membrane potential-dependent firing or regular firing phenotype, due to different low-voltage-activated potassium currents. These different excitability properties destine the two types for distinct functions, because the former is essentially silenced during realistic 8–15 Hz oscillations. By contrast, the general intrinsic excitability, morphology and gene-profiles of the two types were surprisingly similar. Even the expression of Kv4.3 channels were comparable, despite evidences showing that Kv4.3-mediated currents underlie the distinct firing properties. Instead, the firing phenotypes were correlated with the presence of distinct isoforms of Kv4 auxiliary subunits (KChIP1 vs. KChIP4e and DPP6S). Our results reveal the underlying mechanisms of two previously unknown types of CCK+INs and demonstrate that alternative splicing of few genes, which may be viewed as a minor change in the cells’ whole transcriptome, can determine cell-type identity.
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Affiliation(s)
- Viktor János Oláh
- Laboratory of Cellular Neuropharmacology, Institute of Experimental Medicine, Budapest, Hungary.,János Szentágothai School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - David Lukacsovich
- Laboratory of Neural Connectivity, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Jochen Winterer
- Laboratory of Neural Connectivity, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - Antónia Arszovszki
- Laboratory of Cellular Neuropharmacology, Institute of Experimental Medicine, Budapest, Hungary
| | - Andrea Lőrincz
- Laboratory of Cellular Neurophysiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Zoltan Nusser
- Laboratory of Cellular Neurophysiology, Institute of Experimental Medicine, Budapest, Hungary
| | - Csaba Földy
- Laboratory of Neural Connectivity, Brain Research Institute, University of Zurich, Zurich, Switzerland
| | - János Szabadics
- Laboratory of Cellular Neuropharmacology, Institute of Experimental Medicine, Budapest, Hungary
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Guo YP, Zhi YR, Liu TT, Wang Y, Zhang Y. Global Gene Knockout of Kcnip3 Enhances Pain Sensitivity and Exacerbates Negative Emotions in Rats. Front Mol Neurosci 2019; 12:5. [PMID: 30740043 PMCID: PMC6355686 DOI: 10.3389/fnmol.2019.00005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 01/09/2019] [Indexed: 12/12/2022] Open
Abstract
The Ca2+-binding protein Kv channel interacting protein 3 (KChIP3) or downstream regulatory element antagonist modulator (DREAM), a member of the neuronal calcium sensor (NCS) family, shows remarkable multifunctional properties. It acts as a transcriptional repressor in the nucleus and a modulator of ion channels or receptors, such as Kv4, NMDA receptors and TRPV1 channels on the cytomembrane. Previous studies of Kcnip3-/- mice have indicated that KChIP3 facilitates pain hypersensitivity by repressing Pdyn expression in the spinal cord. Conversely, studies from transgenic daDREAM (dominant active DREAM) mice indicated that KChIP3 contributes to analgesia by repressing Bdnf expression and attenuating the development of central sensitization. To further determine the role of KChIP3 in pain transmission and its possible involvement in emotional processing, we assessed the pain sensitivity and negative emotional behaviors of Kcnip3-/- rats. The knockout rats showed higher pain sensitivity compared to the wild-type rats both in the acute nociceptive pain model and in the late phase (i.e., 2, 4 and 6 days post complete Freund’s adjuvant injection) of the chronic inflammatory pain model. Importantly, Kcnip3-/- rats displayed stronger aversion to the pain-associated compartment, higher anxiety level and aggravated depression-like behavior. Furthermore, RNA-Seq transcriptional profiling of the forebrain cortex were compared between wild-type and Kcnip3-/- rats. Among the 68 upregulated genes, 19 genes (including Nr4a2, Ret, Cplx3, Rgs9, and Itgad) are associated with neural development or synaptic transmission, particularly dopamine neurotransmission. Among the 79 downregulated genes, 16 genes (including Col3a1, Itm2a, Pcdhb3, Pcdhb22, Pcdhb20, Ddc, and Sncaip) are associated with neural development or dopaminergic transmission. Transcriptional upregulation of Nr4a2, Ret, Cplx3 and Rgs9, and downregulation of Col3a1, Itm2a, Pcdhb3 and Ddc, were validated by qPCR analysis. In summary, our studies showed that Kcnip3-/- rats displayed higher pain sensitivity and stronger negative emotions, suggesting an involvement of KChIP3 in negative emotions and possible role in central nociceptive processing.
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Affiliation(s)
- Yu-Peng Guo
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Key Laboratory for Neuroscience, Ministry of Education and Ministry of National Health, Peking University, Beijing, China
| | - Yu-Ru Zhi
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Key Laboratory for Neuroscience, Ministry of Education and Ministry of National Health, Peking University, Beijing, China
| | - Ting-Ting Liu
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Key Laboratory for Neuroscience, Ministry of Education and Ministry of National Health, Peking University, Beijing, China
| | - Yun Wang
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Key Laboratory for Neuroscience, Ministry of Education and Ministry of National Health, Peking University, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, China
| | - Ying Zhang
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Key Laboratory for Neuroscience, Ministry of Education and Ministry of National Health, Peking University, Beijing, China
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KChIP3 N-Terminal 31-50 Fragment Mediates Its Association with TRPV1 and Alleviates Inflammatory Hyperalgesia in Rats. J Neurosci 2018; 38:1756-1773. [PMID: 29335353 DOI: 10.1523/jneurosci.2242-17.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 01/02/2018] [Accepted: 01/05/2018] [Indexed: 02/01/2023] Open
Abstract
Potassium voltage-gated channel interacting protein 3 (KChIP3), also termed downstream regulatory element antagonist modulator (DREAM) and calsenilin, is a multifunctional protein belonging to the neuronal calcium sensor (NCS) family. Recent studies revealed the expression of KChIP3 in dorsal root ganglion (DRG) neurons, suggesting the potential role of KChIP3 in peripheral sensory processing. Herein, we show that KChIP3 colocalizes with transient receptor potential ion channel V1 (TRPV1), a critical molecule involved in peripheral sensitization during inflammatory pain. Furthermore, the N-terminal 31-50 fragment of KChIP3 is capable of binding both the intracellular N and C termini of TRPV1, which substantially decreases the surface localization of TRPV1 and the subsequent Ca2+ influx through the channel. Importantly, intrathecal administration of the transmembrane peptide transactivator of transcription (TAT)-31-50 remarkably reduces Ca2+ influx via TRPV1 in DRG neurons and alleviates thermal hyperalgesia and gait alterations in a complete Freund's adjuvant-induced inflammatory pain model in male rats. Moreover, intraplantar injection of TAT-31-50 attenuated the capsaicin-evoked spontaneous pain behavior and thermal hyperalgesia, which further strengthened the regulatory role of TAT-31-50 on TRPV1 channel. In addition, TAT-31-50 could also alleviate inflammatory thermal hyperalgesia in kcnip3-/- rats generated in our study, suggesting that the analgesic effect mediated by TAT-31-50 is independent of endogenous KChIP3. Our study reveals a novel peripheral mechanism for the analgesic function of KChIP3 and provides a potential analgesic agent, TAT-31-50, for the treatment of inflammatory pain.SIGNIFICANCE STATEMENT Inflammatory pain arising from inflamed or injured tissues significantly compromises the quality of life in patients. This study aims to elucidate the role of peripheral potassium channel interacting protein 3 (KChIP3) in inflammatory pain. Direct interaction of the KChIP3 N-terminal 31-50 fragment with transient receptor potential ion channel V1 (TRPV1) was demonstrated. The KChIP3-TRPV1 interaction reduces the surface localization of TRPV1 and thus alleviates heat hyperalgesia and gait alterations induced by peripheral inflammation. Furthermore, the transmembrane transactivator of transcription (TAT)-31-50 peptide showed analgesic effects on inflammatory hyperalgesia independently of endogenous KChIP3. This work reveals a novel mechanism of peripheral KChIP3 in inflammatory hyperalgesia that is distinct from its classical role as a transcriptional repressor in pain modulation.
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Potassium Channel Interacting Protein 2 (KChIP2) is not a transcriptional regulator of cardiac electrical remodeling. Sci Rep 2016; 6:28760. [PMID: 27349185 PMCID: PMC4923891 DOI: 10.1038/srep28760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 06/08/2016] [Indexed: 12/20/2022] Open
Abstract
The heart-failure relevant Potassium Channel Interacting Protein 2 (KChIP2) augments CaV1.2 and KV4.3. KChIP3 represses CaV1.2 transcription in cardiomyocytes via interaction with regulatory DNA elements. Hence, we tested nuclear presence of KChIP2 and if KChIP2 translocates into the nucleus in a Ca2+ dependent manner. Cardiac biopsies from human heart-failure patients and healthy donor controls showed that nuclear KChIP2 abundance was significantly increased in heart failure; however, this was secondary to a large variation of total KChIP2 content. Administration of ouabain did not increase KChIP2 content in nuclear protein fractions in anesthetized mice. KChIP2 was expressed in cell lines, and Ca2+ ionophores were applied in a concentration- and time-dependent manner. The cell lines had KChIP2-immunoreactive protein in the nucleus in the absence of treatments to modulate intracellular Ca2+ concentration. Neither increasing nor decreasing intracellular Ca2+ concentrations caused translocation of KChIP2. Microarray analysis did not identify relief of transcriptional repression in murine KChIP2−/− heart samples. We conclude that although there is a baseline presence of KChIP2 in the nucleus both in vivo and in vitro, KChIP2 does not directly regulate transcriptional activity. Moreover, the nuclear transport of KChIP2 is not dependent on Ca2+. Thus, KChIP2 does not function as a conventional transcription factor in the heart.
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Néant I, Mellström B, Gonzalez P, Naranjo JR, Moreau M, Leclerc C. Kcnip1 a Ca²⁺-dependent transcriptional repressor regulates the size of the neural plate in Xenopus. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:2077-85. [PMID: 25499267 DOI: 10.1016/j.bbamcr.2014.12.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 11/28/2014] [Accepted: 12/03/2014] [Indexed: 12/30/2022]
Abstract
In amphibian embryos, our previous work has demonstrated that calcium transients occurring in the dorsal ectoderm at the onset of gastrulation are necessary and sufficient to engage the ectodermal cells into a neural fate by inducing neural specific genes. Some of these genes are direct targets of calcium. Here we search for a direct transcriptional mechanism by which calcium signals are acting. The only known mechanism responsible for a direct action of calcium on gene transcription involves an EF-hand Ca²⁺ binding protein which belongs to a group of four proteins (Kcnip1 to 4). Kcnip protein can act in a Ca²⁺-dependent manner as a transcriptional repressor by binding to a specific DNA sequence, the Downstream Regulatory Element (DRE) site. In Xenopus, among the four kcnips, we show that only kcnip1 is timely and spatially present in the presumptive neural territories and is able to bind DRE sites in a Ca²⁺-dependent manner. The loss of function of kcnip1 results in the expansion of the neural plate through an increased proliferation of neural progenitors. Later on, this leads to an impairment in the development of anterior neural structures. We propose that, in the embryo, at the onset of neurogenesis Kcnip1 is the Ca²⁺-dependent transcriptional repressor that controls the size of the neural plate. This article is part of a Special Issue entitled: 13th European Symposium on Calcium.
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Affiliation(s)
- Isabelle Néant
- Université Toulouse 3, Centre de Biologie du Développement, 118 routes de Narbonne, F31062 Toulouse, Cedex 04, France; CNRS UMR5547, Toulouse F31062 France; GDRE CNRS, n° 731, Toulouse, France; Centro Nacional de Biotechnología, CSIC, Madrid, Spain; CIBERNED, Madrid, Spain
| | - Britt Mellström
- Centro Nacional de Biotechnología, CSIC, Madrid, Spain; CIBERNED, Madrid, Spain
| | - Paz Gonzalez
- Centro Nacional de Biotechnología, CSIC, Madrid, Spain; CIBERNED, Madrid, Spain
| | - Jose R Naranjo
- GDRE CNRS, n° 731, Toulouse, France; Centro Nacional de Biotechnología, CSIC, Madrid, Spain; CIBERNED, Madrid, Spain
| | - Marc Moreau
- Université Toulouse 3, Centre de Biologie du Développement, 118 routes de Narbonne, F31062 Toulouse, Cedex 04, France; CNRS UMR5547, Toulouse F31062 France; GDRE CNRS, n° 731, Toulouse, France
| | - Catherine Leclerc
- Université Toulouse 3, Centre de Biologie du Développement, 118 routes de Narbonne, F31062 Toulouse, Cedex 04, France; CNRS UMR5547, Toulouse F31062 France; GDRE CNRS, n° 731, Toulouse, France.
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Irvin MR, Zhi D, Aslibekyan S, Claas SA, Absher DM, Ordovas JM, Tiwari HK, Watkins S, Arnett DK. Genomics of post-prandial lipidomic phenotypes in the Genetics of Lipid lowering Drugs and Diet Network (GOLDN) study. PLoS One 2014; 9:e99509. [PMID: 24905834 PMCID: PMC4048279 DOI: 10.1371/journal.pone.0099509] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 05/15/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Increased postprandial lipid (PPL) response to dietary fat intake is a heritable risk factor for cardiovascular disease (CVD). Variability in postprandial lipids results from the complex interplay of dietary and genetic factors. We hypothesized that detailed lipid profiles (eg, sterols and fatty acids) may help elucidate specific genetic and dietary pathways contributing to the PPL response. METHODS AND RESULTS We used gas chromatography mass spectrometry to quantify the change in plasma concentration of 35 fatty acids and 11 sterols between fasting and 3.5 hours after the consumption of a high-fat meal (PPL challenge) among 40 participants from the GOLDN study. Correlations between sterols, fatty acids and clinical measures were calculated. Mixed linear regression was used to evaluate associations between lipidomic profiles and genomic markers including single nucleotide polymorphisms (SNPs) and methylation markers derived from the Affymetrix 6.0 array and the Illumina Methyl450 array, respectively. After the PPL challenge, fatty acids increased as well as sterols associated with cholesterol absorption, while sterols associated with cholesterol synthesis decreased. PPL saturated fatty acids strongly correlated with triglycerides, very low-density lipoprotein, and chylomicrons. Two SNPs (rs12247017 and rs12240292) in the sorbin and SH3 domain containing 1 (SORBS1) gene were associated with b-Sitosterol after correction for multiple testing (P≤4.5*10(-10)). SORBS1 has been linked to obesity and insulin signaling. No other markers reached the genome-wide significance threshold, yet several other biologically relevant loci are highlighted (eg, PRIC285, a co-activator of PPARa). CONCLUSIONS Integration of lipidomic and genomic data has the potential to identify new biomarkers of CVD risk.
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Affiliation(s)
- Marguerite R. Irvin
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail:
| | - Degui Zhi
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Stella Aslibekyan
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Steven A. Claas
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Devin M. Absher
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama, United States of America
| | - Jose M. Ordovas
- Department of Epidemiology, Atherothrombosis and Imaging, Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
- Instituto Madrileño de Estudios Avanzados Alimentacion, Madrid, Spain
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States of America
| | - Hemant K. Tiwari
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Steve Watkins
- Metabolon, Lipomics Division, Research Triangle Park, North Carolina, United States of America
| | - Donna K. Arnett
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
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Jerng HH, Pfaffinger PJ. Modulatory mechanisms and multiple functions of somatodendritic A-type K (+) channel auxiliary subunits. Front Cell Neurosci 2014; 8:82. [PMID: 24723849 PMCID: PMC3973911 DOI: 10.3389/fncel.2014.00082] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 03/03/2014] [Indexed: 12/13/2022] Open
Abstract
Auxiliary subunits are non-conducting, modulatory components of the multi-protein ion channel complexes that underlie normal neuronal signaling. They interact with the pore-forming α-subunits to modulate surface distribution, ion conductance, and channel gating properties. For the somatodendritic subthreshold A-type potassium (ISA) channel based on Kv4 α-subunits, two types of auxiliary subunits have been extensively studied: Kv channel-interacting proteins (KChIPs) and dipeptidyl peptidase-like proteins (DPLPs). KChIPs are cytoplasmic calcium-binding proteins that interact with intracellular portions of the Kv4 subunits, whereas DPLPs are type II transmembrane proteins that associate with the Kv4 channel core. Both KChIPs and DPLPs genes contain multiple start sites that are used by various neuronal populations to drive the differential expression of functionally distinct N-terminal variants. In turn, these N-terminal variants generate tremendous functional diversity across the nervous system. Here, we focus our review on (1) the molecular mechanism underlying the unique properties of different N-terminal variants, (2) the shaping of native ISA properties by the concerted actions of KChIPs and DPLP variants, and (3) the surprising ways that KChIPs and DPLPs coordinate the activity of multiple channels to fine-tune neuronal excitability. Unlocking the unique contributions of different auxiliary subunit N-terminal variants may provide an important opportunity to develop novel targeted therapeutics to treat numerous neurological disorders.
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Affiliation(s)
- Henry H. Jerng
- Department of Neuroscience, Baylor College of MedicineHouston, TX, USA
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