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Chen HW, Ma CP, Chin E, Chen YT, Wang TC, Kuo YP, Su CH, Huang PJ, Tan BCM. Imbalance in Unc80 RNA Editing Disrupts Dynamic Neuronal Activity and Olfactory Perception. Int J Mol Sci 2024; 25:5985. [PMID: 38892173 PMCID: PMC11172567 DOI: 10.3390/ijms25115985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/22/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024] Open
Abstract
A-to-I RNA editing, catalyzed by the ADAR protein family, significantly contributes to the diversity and adaptability of mammalian RNA signatures, aligning with developmental and physiological needs. Yet, the functions of many editing sites are still to be defined. The Unc80 gene stands out in this context due to its brain-specific expression and the evolutionary conservation of its codon-altering editing event. The precise biological functions of Unc80 and its editing, however, are still largely undefined. In this study, we first demonstrated that Unc80 editing occurs in an ADAR2-dependent manner and is exclusive to the brain. By employing the CRISPR/Cas9 system to generate Unc80 knock-in mouse models that replicate the natural editing variations, our findings revealed that mice with the "gain-of-editing" variant (Unc80G/G) exhibit heightened basal neuronal activity in critical olfactory regions, compared to the "loss-of-editing" (Unc80S/S) counterparts. Moreover, an increase in glutamate levels was observed in the olfactory bulbs of Unc80G/G mice, indicating altered neurotransmitter dynamics. Behavioral analysis of odor detection revealed distinctive responses to novel odors-both Unc80 deficient (Unc80+/-) and Unc80S/S mice demonstrated prolonged exploration times and heightened dishabituation responses. Further elucidating the olfactory connection of Unc80 editing, transcriptomic analysis of the olfactory bulb identified significant alterations in gene expression that corroborate the behavioral and physiological findings. Collectively, our research advances the understanding of Unc80's neurophysiological functions and the impact of its editing on the olfactory sensory system, shedding light on the intricate molecular underpinnings of olfactory perception and neuronal activity.
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Affiliation(s)
- Hui-Wen Chen
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (H.-W.C.); (C.-P.M.); (E.C.); (Y.-T.C.); (P.-J.H.)
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Chung-Pei Ma
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (H.-W.C.); (C.-P.M.); (E.C.); (Y.-T.C.); (P.-J.H.)
| | - En Chin
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (H.-W.C.); (C.-P.M.); (E.C.); (Y.-T.C.); (P.-J.H.)
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Yi-Tung Chen
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (H.-W.C.); (C.-P.M.); (E.C.); (Y.-T.C.); (P.-J.H.)
- Molecular Medicine Research Center, Chang Gung University, Taoyuan 333, Taiwan;
| | - Teh-Cheng Wang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Yu-Ping Kuo
- Molecular Medicine Research Center, Chang Gung University, Taoyuan 333, Taiwan;
| | - Chia-Hao Su
- Center for General Education, Chang Gung University, Taoyuan 333, Taiwan;
- Department of Radiation Oncology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan
| | - Po-Jung Huang
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (H.-W.C.); (C.-P.M.); (E.C.); (Y.-T.C.); (P.-J.H.)
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
- Genomic Medicine Core Laboratory, Lin-Kou Medical Center, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Bertrand Chin-Ming Tan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (H.-W.C.); (C.-P.M.); (E.C.); (Y.-T.C.); (P.-J.H.)
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
- Division of Colon and Rectal Surgery, Lin-Kou Medical Center, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
- Department of Neurosurgery, Lin-Kou Medical Center, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
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Monteil A, Guérineau NC, Gil-Nagel A, Parra-Diaz P, Lory P, Senatore A. New insights into the physiology and pathophysiology of the atypical sodium leak channel NALCN. Physiol Rev 2024; 104:399-472. [PMID: 37615954 DOI: 10.1152/physrev.00014.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 07/13/2023] [Accepted: 08/15/2023] [Indexed: 08/25/2023] Open
Abstract
Cell excitability and its modulation by hormones and neurotransmitters involve the concerted action of a large repertoire of membrane proteins, especially ion channels. Unique complements of coexpressed ion channels are exquisitely balanced against each other in different excitable cell types, establishing distinct electrical properties that are tailored for diverse physiological contributions, and dysfunction of any component may induce a disease state. A crucial parameter controlling cell excitability is the resting membrane potential (RMP) set by extra- and intracellular concentrations of ions, mainly Na+, K+, and Cl-, and their passive permeation across the cell membrane through leak ion channels. Indeed, dysregulation of RMP causes significant effects on cellular excitability. This review describes the molecular and physiological properties of the Na+ leak channel NALCN, which associates with its accessory subunits UNC-79, UNC-80, and NLF-1/FAM155 to conduct depolarizing background Na+ currents in various excitable cell types, especially neurons. Studies of animal models clearly demonstrate that NALCN contributes to fundamental physiological processes in the nervous system including the control of respiratory rhythm, circadian rhythm, sleep, and locomotor behavior. Furthermore, dysfunction of NALCN and its subunits is associated with severe pathological states in humans. The critical involvement of NALCN in physiology is now well established, but its study has been hampered by the lack of specific drugs that can block or agonize NALCN currents in vitro and in vivo. Molecular tools and animal models are now available to accelerate our understanding of how NALCN contributes to key physiological functions and the development of novel therapies for NALCN channelopathies.
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Affiliation(s)
- Arnaud Monteil
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
- LabEx "Ion Channel Science and Therapeutics," Montpellier, France
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Nathalie C Guérineau
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
- LabEx "Ion Channel Science and Therapeutics," Montpellier, France
| | - Antonio Gil-Nagel
- Department of Neurology, Epilepsy Program, Hospital Ruber Internacional, Madrid, Spain
| | - Paloma Parra-Diaz
- Department of Neurology, Epilepsy Program, Hospital Ruber Internacional, Madrid, Spain
| | - Philippe Lory
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
- LabEx "Ion Channel Science and Therapeutics," Montpellier, France
| | - Adriano Senatore
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
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Zhou C, Zhou Q, He X, He Y, Wang X, Zhu X, Zhang Y, Ma L. Differential modulation of C. elegans motor behavior by NALCN and two-pore domain potassium channels. PLoS Genet 2022; 18:e1010126. [PMID: 35482723 PMCID: PMC9049526 DOI: 10.1371/journal.pgen.1010126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 02/28/2022] [Indexed: 11/18/2022] Open
Abstract
Two-pore domain potassium channels (K2P) are a large family of “background” channels that allow outward “leak” of potassium ions. The NALCN/UNC80/UNC79 complex is a non-selective channel that allows inward flow of sodium and other cations. It is unclear how K2Ps and NALCN differentially modulate animal behavior. Here, we found that loss of function (lf) in the K2P gene twk-40 suppressed the reduced body curvatures of C. elegans NALCN(lf) mutants. twk-40(lf) caused a deep body curvature and extended backward locomotion, and these phenotypes appeared to be associated with neuron-specific expression of twk-40 and distinct twk-40 transcript isoforms. To survey the functions of other less studied K2P channels, we examined loss-of-function mutants of 13 additional twk genes expressed in the motor circuit and detected defective body curvature and/or locomotion in mutants of twk-2, twk-17, twk-30, twk-48, unc-58, and the previously reported twk-7. We generated presumptive gain-of-function (gf) mutations in twk-40, twk-2, twk-7, and unc-58 and found that they caused paralysis. Further analyses detected variable genetic interactions between twk-40 and other twk genes, an interdependence between twk-40 and twk-2, and opposite behavioral effects between NALCN and twk-2, twk-7, or unc-58. Finally, we found that the hydrophobicity/hydrophilicity property of TWK-40 residue 159 could affect the channel activity. Together, our study identified twk-40 as a novel modulator of the motor behavior, uncovered potential behavioral effects of five other K2P genes and suggests that NALCN and some K2Ps can oppositely affect C. elegans behavior.
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Affiliation(s)
- Chuanman Zhou
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Qian Zhou
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Xiaohui He
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Yunxia He
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Xiaoqin Wang
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Xiaowei Zhu
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Yujia Zhang
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Long Ma
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Molecular Precision Medicine, Central South University, Changsha, Hunan, China
- * E-mail:
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Liao Z, Liu Y, Wang Y, Lu Q, Peng Y, Liu Q. Case Report: A de novo Variant in NALCN Associated With CLIFAHDD Syndrome in a Chinese Infant. Front Pediatr 2022; 10:927392. [PMID: 35911839 PMCID: PMC9326163 DOI: 10.3389/fped.2022.927392] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The NALCN encodes a sodium ion leak channel that regulates nerve-resting conductance and excitability. NALCN variants are associated with two neurodevelopmental disorders, one is CLIFAHDD (autosomal dominant congenital contractures of the limbs and face, hypotonia, and developmental delay, OMIM #616266) and another is IHPRF (infantile hypotonia with psychomotor retardation, and characteristic facies 1, OMIM #615419). CASE PRESENTATION In the current study, a Chinese infant that manifested abnormal facial features, adducted thumbs, and neurodevelopmental retardation was diagnosed with CLIFAHDD syndrome. A trio-based whole-exome sequencing revealed that the infant harbored a de novo variant of the NALCN gene (c.4300A>G, p.I1434V). CONCLUSIONS Our findings further enriched the variant spectrum of the NALCN gene and may expand the clinical range of NALCN-related disorders.
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Affiliation(s)
- Zhenyu Liao
- Neonatology Department of Hunan Children's Hospital, Changsha, China
| | - Yali Liu
- Neonatology Department of Changsha Country Maternal and Child Health Care Hospital, Changsha, China
| | - Yimin Wang
- GeneMind Biosciences Company Limited, ShenZhen, China.,College of Pharmacy, Xiangnan University, Chenzhou, China
| | - Qin Lu
- College of Pharmacy, Xiangnan University, Chenzhou, China.,GeneTalks Biotech Co., Ltd., Changsha, China
| | - Yu Peng
- Pediatrics Research Institute of Hunan Province, Hunan Children's Hospital, Changsha, China
| | - Qingsong Liu
- Department of Cardiothoracic Surgery, Hunan Children's Hospital, Changsha, China
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The Genomic Impact of Selection for Virulence against Resistance in the Potato Cyst Nematode, Globodera pallida. Genes (Basel) 2020; 11:genes11121429. [PMID: 33260722 PMCID: PMC7760817 DOI: 10.3390/genes11121429] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 11/17/2022] Open
Abstract
Although the use of natural resistance is the most effective management approach against the potato cyst nematode (PCN) Globodera pallida, the existence of pathotypes with different virulence characteristics constitutes a constraint towards this goal. Two resistance sources, GpaV (from Solanum vernei) and H3 from S. tuberosum ssp. andigena CPC2802 (from the Commonwealth Potato Collection) are widely used in potato breeding programmes in European potato industry. However, the use of resistant cultivars may drive strong selection towards virulence, which allows the increase in frequency of virulent alleles in the population and therefore, the emergence of highly virulent nematode lineages. This study aimed to identify Avirulence (Avr) genes in G. pallida populations selected for virulence on the above resistance sources, and the genomic impact of selection processes on the nematode. The selection drive in the populations was found to be specific to their genetic background. At the genomic level, 11 genes were found that represent candidate Avr genes. Most of the variant calls determining selection were associated with H3-selected populations, while many of them seem to be organised in genomic islands facilitating selection evolution. These phenotypic and genomic findings combined with histological studies performed revealed potential mechanisms underlying selection in G. pallida.
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