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Chesneau B, Calvas P, Cassagne M, Varenne F, Rozet JM, Bonneville F, Chassaing N, Fournié P, Fares-Taie L, Plaisancié J. ITPR1: The missing gene in miosis-ataxia syndrome? Am J Med Genet A 2024; 194:e63655. [PMID: 38711238 DOI: 10.1002/ajmg.a.63655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/23/2024] [Accepted: 04/26/2024] [Indexed: 05/08/2024]
Abstract
The association of early-onset non-progressive ataxia and miosis is an extremely rare phenotypic entity occasionally reported in the literature. To date, only one family (two siblings and their mother) has benefited from a genetic diagnosis by the identification of a missense heterozygous variant (p.Arg36Cys) in the ITPR1 gene. This gene encodes the inositol 1,4,5-trisphosphate receptor type 1, an intracellular channel that mediates calcium release from the endoplasmic reticulum. Deleterious variants in this gene are known to be associated with two types of spinocerebellar ataxia, SCA15 and SCA29, and with Gillespie syndrome that is associated with ataxia, partial iris hypoplasia, and intellectual disability. In this work, we describe a novel individual carrying a heterozygous missense variant (p.Arg36Pro) at the same position in the N-terminal suppressor domain of ITPR1 as the family previously reported, with the same phenotype associating early-onset non-progressive ataxia and miosis. This second report confirms the implication of ITPR1 in the miosis-ataxia syndrome and therefore broadens the clinical spectrum of the gene. Moreover, the high specificity of the phenotype makes it a recognizable syndrome of genetic origin.
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Affiliation(s)
- Bertrand Chesneau
- Laboratoire de Référence (LBMR) des anomalies malformatives de l'œil, Institut Fédératif de Biologie (IFB), CHU Toulouse, Toulouse, France
- Centre de Référence des Affections Rares en Génétique Ophtalmologique, CARGO, site constitutif, CHU Toulouse, Toulouse, France
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Patrick Calvas
- Centre de Référence des Affections Rares en Génétique Ophtalmologique, CARGO, site constitutif, CHU Toulouse, Toulouse, France
| | | | - Fanny Varenne
- Centre de Référence des Affections Rares en Génétique Ophtalmologique, CARGO, site constitutif, CHU Toulouse, Toulouse, France
- Service d'Ophtalmologie, Hôpital Purpan, Toulouse, France
| | - Jean-Michel Rozet
- Laboratoire de Génétique Ophtalmologique, INSERM U1163, Institut Imagine, Paris, France
| | - Fabrice Bonneville
- Département de Neuroradiologie, Centre Hospitalier Universitaire de Toulouse, Toulouse, France
| | - Nicolas Chassaing
- Laboratoire de Référence (LBMR) des anomalies malformatives de l'œil, Institut Fédératif de Biologie (IFB), CHU Toulouse, Toulouse, France
- Centre de Référence des Affections Rares en Génétique Ophtalmologique, CARGO, site constitutif, CHU Toulouse, Toulouse, France
| | - Pierre Fournié
- Service d'Ophtalmologie, Hôpital Purpan, Toulouse, France
| | - Lucas Fares-Taie
- Laboratoire de Génétique Ophtalmologique, INSERM U1163, Institut Imagine, Paris, France
| | - Julie Plaisancié
- Laboratoire de Référence (LBMR) des anomalies malformatives de l'œil, Institut Fédératif de Biologie (IFB), CHU Toulouse, Toulouse, France
- Centre de Référence des Affections Rares en Génétique Ophtalmologique, CARGO, site constitutif, CHU Toulouse, Toulouse, France
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
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Reis LM, Seese SE, Costakos D, Semina EV. Congenital anterior segment ocular disorders: Genotype-phenotype correlations and emerging novel mechanisms. Prog Retin Eye Res 2024; 102:101288. [PMID: 39097141 PMCID: PMC11392650 DOI: 10.1016/j.preteyeres.2024.101288] [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: 03/30/2023] [Revised: 07/30/2024] [Accepted: 07/31/2024] [Indexed: 08/05/2024]
Abstract
Development of the anterior segment of the eye requires reciprocal sequential interactions between the arising tissues, facilitated by numerous genetic factors. Disruption of any of these processes results in congenital anomalies in the affected tissue(s) leading to anterior segment disorders (ASD) including aniridia, Axenfeld-Rieger anomaly, congenital corneal opacities (Peters anomaly, cornea plana, congenital primary aphakia), and primary congenital glaucoma. Current understanding of the genetic factors involved in ASD remains incomplete, with approximately 50% overall receiving a genetic diagnosis. While some genes are strongly associated with a specific clinical diagnosis, the majority of known factors are linked with highly variable phenotypic presentations, with pathogenic variants in FOXC1, CYP1B1, and PITX2 associated with the broadest spectrum of ASD conditions. This review discusses typical clinical presentations including associated systemic features of various forms of ASD; the latest functional data and genotype-phenotype correlations related to 25 ASD factors including newly identified genes; promising novel candidates; and current and emerging treatments for these complex conditions. Recent developments of interest in the genetics of ASD include identification of phenotypic expansions for several factors, discovery of multiple modes of inheritance for some genes, and novel mechanisms including a growing number of non-coding variants and alleles affecting specific domains/residues and requiring further studies.
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Affiliation(s)
- Linda M Reis
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA.
| | - Sarah E Seese
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA.
| | - Deborah Costakos
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA.
| | - Elena V Semina
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA; Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA; Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA.
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Li R, Liu X, Ke C, Zeng F, Zeng Q, Xu X, Fan X, Zhang Y, Hou Q. ITPR1 variant-induced autosomal dominant hereditary spastic paraplegia in a Chinese family. Front Neurol 2024; 15:1365787. [PMID: 39011359 PMCID: PMC11247953 DOI: 10.3389/fneur.2024.1365787] [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: 01/05/2024] [Accepted: 05/23/2024] [Indexed: 07/17/2024] Open
Abstract
Hereditary spastic paraplegia (HSP) is a rare neurodegenerative disease prominently characterized by slowly progressive lower limb weakness and spasticity. The significant genotypic and phenotypic heterogeneity of this disease makes its accurate diagnosis challenging. In this study, we identified the NM_001168272: c.2714A > G (chr3.hg19: g.4716912A > G, N905S) variant in the ITPR1 gene in a three-generation Chinese family with multiple individuals affected by HSP, which we believed to be associated with HSP pathogenesis. To confirm, we performed whole exome sequencing, copy number variant assays, dynamic mutation analysis of the entire family, and protein structure prediction. The variant identified in this study was in the coupling domain, and this is the first corroborated report assigning ITPR1 variants to HSP. These findings expand the clinical and genetic spectrum of HSP and provide important data for its genetic analysis and diagnosis.
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Affiliation(s)
- Rui Li
- Department of Neurology, Ningbo Medical Center Lihuili Hospital, Ningbo, Zhejiang, China
| | - Xuan Liu
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Chenming Ke
- Department of Neurology, Clinical Neuroscience Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Fanli Zeng
- Department of Neurology, Clinical Neuroscience Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Qingyi Zeng
- Department of Neurology, Ningbo Medical Center Lihuili Hospital, Ningbo, Zhejiang, China
| | - Xiaowei Xu
- Department of Neurology, Clinical Neuroscience Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Xiaoqin Fan
- Department of Neurology, Ningbo Medical Center Lihuili Hospital, Ningbo, Zhejiang, China
| | - Ying Zhang
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Qinghua Hou
- Department of Neurology, Clinical Neuroscience Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
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Makio T, Simmen T. Not So Rare: Diseases Based on Mutant Proteins Controlling Endoplasmic Reticulum-Mitochondria Contact (MERC) Tethering. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2024; 7:25152564241261228. [PMID: 39070058 PMCID: PMC11273598 DOI: 10.1177/25152564241261228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/12/2024] [Accepted: 05/27/2024] [Indexed: 07/30/2024]
Abstract
Mitochondria-endoplasmic reticulum contacts (MERCs), also called endoplasmic reticulum (ER)-mitochondria contact sites (ERMCS), are the membrane domains, where these two organelles exchange lipids, Ca2+ ions, and reactive oxygen species. This crosstalk is a major determinant of cell metabolism, since it allows the ER to control mitochondrial oxidative phosphorylation and the Krebs cycle, while conversely, it allows the mitochondria to provide sufficient ATP to control ER proteostasis. MERC metabolic signaling is under the control of tethers and a multitude of regulatory proteins. Many of these proteins have recently been discovered to give rise to rare diseases if their genes are mutated. Surprisingly, these diseases share important hallmarks and cause neurological defects, sometimes paired with, or replaced by skeletal muscle deficiency. Typical symptoms include developmental delay, intellectual disability, facial dysmorphism and ophthalmologic defects. Seizures, epilepsy, deafness, ataxia, or peripheral neuropathy can also occur upon mutation of a MERC protein. Given that most MERC tethers and regulatory proteins have secondary functions, some MERC protein-based diseases do not fit into this categorization. Typically, however, the proteins affected in those diseases have dominant functions unrelated to their roles in MERCs tethering or their regulation. We are discussing avenues to pharmacologically target genetic diseases leading to MERC defects, based on our novel insight that MERC defects lead to common characteristics in rare diseases. These shared characteristics of MERCs disorders raise the hope that they may allow for similar treatment options.
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Affiliation(s)
- Tadashi Makio
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Thomas Simmen
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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Tolonen JP, Parolin Schnekenberg R, McGowan S, Sims D, McEntagart M, Elmslie F, Shears D, Stewart H, Tofaris GK, Dabir T, Morrison PJ, Johnson D, Hadjivassiliou M, Ellard S, Shaw‐Smith C, Znaczko A, Dixit A, Suri M, Sarkar A, Harrison RE, Jones G, Houlden H, Ceravolo G, Jarvis J, Williams J, Shanks ME, Clouston P, Rankin J, Blumkin L, Lerman‐Sagie T, Ponger P, Raskin S, Granath K, Uusimaa J, Conti H, McCann E, Joss S, Blakes AJ, Metcalfe K, Kingston H, Bertoli M, Kneen R, Lynch SA, Martínez Albaladejo I, Moore AP, Jones WD, Becker EB, Németh AH. Detailed Analysis of ITPR1 Missense Variants Guides Diagnostics and Therapeutic Design. Mov Disord 2024; 39:141-151. [PMID: 37964426 PMCID: PMC10952845 DOI: 10.1002/mds.29651] [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: 07/30/2023] [Revised: 09/16/2023] [Accepted: 10/16/2023] [Indexed: 11/16/2023] Open
Abstract
BACKGROUND The ITPR1 gene encodes the inositol 1,4,5-trisphosphate (IP3 ) receptor type 1 (IP3 R1), a critical player in cerebellar intracellular calcium signaling. Pathogenic missense variants in ITPR1 cause congenital spinocerebellar ataxia type 29 (SCA29), Gillespie syndrome (GLSP), and severe pontine/cerebellar hypoplasia. The pathophysiological basis of the different phenotypes is poorly understood. OBJECTIVES We aimed to identify novel SCA29 and GLSP cases to define core phenotypes, describe the spectrum of missense variation across ITPR1, standardize the ITPR1 variant nomenclature, and investigate disease progression in relation to cerebellar atrophy. METHODS Cases were identified using next-generation sequencing through the Deciphering Developmental Disorders study, the 100,000 Genomes project, and clinical collaborations. ITPR1 alternative splicing in the human cerebellum was investigated by quantitative polymerase chain reaction. RESULTS We report the largest, multinational case series of 46 patients with 28 unique ITPR1 missense variants. Variants clustered in functional domains of the protein, especially in the N-terminal IP3 -binding domain, the carbonic anhydrase 8 (CA8)-binding region, and the C-terminal transmembrane channel domain. Variants outside these domains were of questionable clinical significance. Standardized transcript annotation, based on our ITPR1 transcript expression data, greatly facilitated analysis. Genotype-phenotype associations were highly variable. Importantly, while cerebellar atrophy was common, cerebellar volume loss did not correlate with symptom progression. CONCLUSIONS This dataset represents the largest cohort of patients with ITPR1 missense variants, expanding the clinical spectrum of SCA29 and GLSP. Standardized transcript annotation is essential for future reporting. Our findings will aid in diagnostic interpretation in the clinic and guide selection of variants for preclinical studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Jussi Pekka Tolonen
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Kavli Institute of Nanoscience DiscoveryUniversity of OxfordOxfordUK
| | - Ricardo Parolin Schnekenberg
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Oxford Center for Genomic MedicineOxford University Hospitals National Health Service Foundation Trust, University of OxfordOxfordUK
| | - Simon McGowan
- Centre for Computational Biology, MRC Weatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
| | - David Sims
- Centre for Computational Biology, MRC Weatherall Institute of Molecular MedicineUniversity of OxfordOxfordUK
| | - Meriel McEntagart
- South West Regional Genetics ServiceSt. George's University HospitalsLondonUK
| | - Frances Elmslie
- South West Regional Genetics ServiceSt. George's University HospitalsLondonUK
| | - Debbie Shears
- Oxford Center for Genomic MedicineOxford University Hospitals National Health Service Foundation Trust, University of OxfordOxfordUK
| | - Helen Stewart
- Oxford Center for Genomic MedicineOxford University Hospitals National Health Service Foundation Trust, University of OxfordOxfordUK
| | - George K. Tofaris
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Kavli Institute of Nanoscience DiscoveryUniversity of OxfordOxfordUK
| | - Tabib Dabir
- Northern Ireland Regional Genetics ServiceBelfast City HospitalBelfastUK
| | - Patrick J. Morrison
- Patrick G. Johnston Centre for Cancer Research and Cell BiologyQueen's University BelfastBelfastUK
| | - Diana Johnson
- Sheffield Clinical Genetics ServiceSheffield Children's NHS Foundation TrustSheffieldUK
| | - Marios Hadjivassiliou
- Department of NeurologyRoyal Hallamshire Hospital, Sheffield Teaching Hospital NHS Foundation TrustSheffieldUK
| | - Sian Ellard
- Exeter Genomics LaboratoryRoyal Devon University Healthcare NHS Foundation TrustUK
| | - Charles Shaw‐Smith
- Peninsula Clinical Genetics Service, Royal Devon University HospitalRoyal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Anna Znaczko
- Peninsula Clinical Genetics Service, Royal Devon University HospitalRoyal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Abhijit Dixit
- Department of Clinical GeneticsNottingham University Hospitals NHS TrustNottinghamUK
| | - Mohnish Suri
- Department of Clinical GeneticsNottingham University Hospitals NHS TrustNottinghamUK
| | - Ajoy Sarkar
- Department of Clinical GeneticsNottingham University Hospitals NHS TrustNottinghamUK
| | - Rachel E. Harrison
- Department of Clinical GeneticsNottingham University Hospitals NHS TrustNottinghamUK
| | - Gabriela Jones
- Department of Clinical GeneticsNottingham University Hospitals NHS TrustNottinghamUK
| | - Henry Houlden
- Department of Neuromuscular DisordersUCL Queen Square Institute of Neurology, University College LondonLondonUK
| | - Giorgia Ceravolo
- Department of Neuromuscular DisordersUCL Queen Square Institute of Neurology, University College LondonLondonUK
- Unit of Pediatric Emergency, Department of Adult and Childhood Human PathologyUniversity Hospital of MessinaMessinaItaly
| | - Joanna Jarvis
- Birmingham Women's and Children's NHS Foundation TrustBirminghamUK
| | - Jonathan Williams
- Oxford Regional Genetics Laboratory, Churchill HospitalOxford University Hospitals NHS Foundation TrustOxfordUK
| | - Morag E. Shanks
- Oxford Regional Genetics Laboratory, Churchill HospitalOxford University Hospitals NHS Foundation TrustOxfordUK
| | - Penny Clouston
- Oxford Regional Genetics Laboratory, Churchill HospitalOxford University Hospitals NHS Foundation TrustOxfordUK
| | - Julia Rankin
- Department of Clinical GeneticsRoyal Devon and Exeter NHS Foundation TrustExeterUK
| | - Lubov Blumkin
- Sackler School of MedicineTel Aviv UniversityTel AvivIsrael
- Pediatric Movement Disorders Service, Pediatric Neurology UnitEdith Wolfson Medical CenterHolonIsrael
| | - Tally Lerman‐Sagie
- Sackler School of MedicineTel Aviv UniversityTel AvivIsrael
- Magen Center for Rare Diseases‐Metabolic, NeurogeneticWolfson Medical CenterHolonIsrael
| | - Penina Ponger
- Sackler School of MedicineTel Aviv UniversityTel AvivIsrael
- Movement Disorders Unit, Department of NeurologyTel Aviv Sourasky Medical CenterTel AvivIsrael
| | - Salmo Raskin
- Genetika Centro de Aconselhamento e LaboratórioCuritibaBrazil
| | - Katariina Granath
- Research Unit of Clinical MedicineMedical Research Center, Oulu University Hospital and University of OuluOuluFinland
| | - Johanna Uusimaa
- Research Unit of Clinical MedicineMedical Research Center, Oulu University Hospital and University of OuluOuluFinland
| | - Hector Conti
- All Wales Medical Genomics ServiceWrexham Maelor HospitalWrexhamUK
| | - Emma McCann
- Liverpool Women's Hospital Foundation TrustLiverpoolUK
| | - Shelagh Joss
- West of Scotland Centre for Genomic MedicineQueen Elizabeth University HospitalGlasgowUK
| | - Alexander J.M. Blakes
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of BiologyMedicine and Health, University of ManchesterManchesterUK
- Manchester Centre for Genomic MedicineUniversity of Manchester, St. Mary's Hospital, Manchester Academic Health Science CentreManchesterUK
| | - Kay Metcalfe
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of BiologyMedicine and Health, University of ManchesterManchesterUK
- Manchester Centre for Genomic MedicineUniversity of Manchester, St. Mary's Hospital, Manchester Academic Health Science CentreManchesterUK
| | - Helen Kingston
- Manchester Centre for Genomic MedicineUniversity of Manchester, St. Mary's Hospital, Manchester Academic Health Science CentreManchesterUK
| | - Marta Bertoli
- Northern Genetics ServiceInternational Centre for LifeNewcastle upon TyneUK
| | - Rachel Kneen
- Department of NeurologyAlder Hey Children's NHS Foundation TrustLiverpoolUK
| | - Sally Ann Lynch
- Department of Clinical GeneticsChildren's Health Ireland (CHI) at CrumlinDublinIreland
| | | | | | - Wendy D. Jones
- North East Thames Regional Genetics ServiceGreat Ormond Street Hospital for Children, Great Ormond Street NHS Foundation TrustLondonUK
| | | | - Esther B.E. Becker
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Kavli Institute of Nanoscience DiscoveryUniversity of OxfordOxfordUK
| | - Andrea H. Németh
- Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Oxford Center for Genomic MedicineOxford University Hospitals National Health Service Foundation Trust, University of OxfordOxfordUK
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Kleyner R, Ung N, Arif M, Marchi E, Amble K, Gavin M, Madrid R, Lyon G. ITPR1-associated spinocerebellar ataxia with craniofacial features-additional evidence for germline mosaicism. Cold Spring Harb Mol Case Stud 2023; 9:a006303. [PMID: 37821226 PMCID: PMC10815276 DOI: 10.1101/mcs.a006303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 10/02/2023] [Indexed: 10/13/2023] Open
Abstract
Inositol 1,4,5-triphosphate receptor type 1 (ITPR1) is an endoplasmic reticulum-bound intracellular inositol triphosphate receptor involved in the regulation of intracellular calcium. Pathogenic variants in ITPR1 are associated with spinocerebellar ataxia (SCA) types 15/16 and 29 and have recently been implicated in a facial microsomia syndrome. In this report, we present a family with three affected individuals found to have a heterozygous missense c.800C > T (predicted p.Thr267Met) who present clinically with a SCA29-like syndrome. All three individuals presented with varying degrees of ataxia, developmental delay, and apparent intellectual disability, as well as craniofacial involvement-an uncommon finding in patients with SCA29. The variant was identified using clinical exome sequencing and validated with Sanger sequencing. It is presumed to be inherited via parental germline mosaicism. We present our findings to provide additional evidence for germline mosaic inheritance of SCA29, as well as to expand the clinical phenotype of the syndrome.
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Affiliation(s)
- Robert Kleyner
- Department of Human Genetics, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
- Department of Neurological Surgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York 11794-8122, USA
| | - Nathaniel Ung
- Department of Human Genetics, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Mohammad Arif
- Department of Human Genetics, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
- Division of Cytogenetics and Molecular Pathology, North Shore University Hospital, Manhasset, New York 11030, USA
| | - Elaine Marchi
- Department of Human Genetics, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Karen Amble
- George A. Jervis Clinic, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Maureen Gavin
- George A. Jervis Clinic, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Ricardo Madrid
- George A. Jervis Clinic, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Gholson Lyon
- Department of Human Genetics, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA;
- George A. Jervis Clinic, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
- Biology PhD Program, The Graduate Center, The City University of New York, New York, New York 10016, USA
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7
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Akçimen F, Lopez ER, Landers JE, Nath A, Chiò A, Chia R, Traynor BJ. Amyotrophic lateral sclerosis: translating genetic discoveries into therapies. Nat Rev Genet 2023; 24:642-658. [PMID: 37024676 PMCID: PMC10611979 DOI: 10.1038/s41576-023-00592-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2023] [Indexed: 04/08/2023]
Abstract
Recent advances in sequencing technologies and collaborative efforts have led to substantial progress in identifying the genetic causes of amyotrophic lateral sclerosis (ALS). This momentum has, in turn, fostered the development of putative molecular therapies. In this Review, we outline the current genetic knowledge, emphasizing recent discoveries and emerging concepts such as the implication of distinct types of mutation, variability in mutated genes in diverse genetic ancestries and gene-environment interactions. We also propose a high-level model to synthesize the interdependent effects of genetics, environmental and lifestyle factors, and ageing into a unified theory of ALS. Furthermore, we summarize the current status of therapies developed on the basis of genetic knowledge established for ALS over the past 30 years, and we discuss how developing treatments for ALS will advance our understanding of targeting other neurological diseases.
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Affiliation(s)
- Fulya Akçimen
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
| | - Elia R Lopez
- Therapeutic Development Branch, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, USA
| | - John E Landers
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute for Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Adriano Chiò
- Rita Levi Montalcini Department of Neuroscience, University of Turin, Turin, Italy
- Institute of Cognitive Sciences and Technologies, C.N.R, Rome, Italy
- Azienda Ospedaliero Universitaria Citta' della Salute e della Scienza, Turin, Italy
| | - Ruth Chia
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Bryan J Traynor
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
- Therapeutic Development Branch, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, USA.
- Department of Neurology, Johns Hopkins University Medical Center, Baltimore, MD, USA.
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8
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Yao J, Ni M, Tian S, Sun B, Wang R, Paul Estillore J, Back TG, Wayne Chen SR. A Gain-of-function Mutation in the Gating Domain of ITPR1 Impairs Motor Movement and Increases Thermal and Mechanical Sensitivity. Neuroscience 2023; 522:11-22. [PMID: 37164302 DOI: 10.1016/j.neuroscience.2023.04.031] [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: 12/10/2021] [Revised: 04/14/2023] [Accepted: 04/30/2023] [Indexed: 05/12/2023]
Abstract
Inositol 1,4,5-trisphosphate receptor type 1 (ITPR1) is an intracellular Ca2+ release channel important for a number of fundamental cellular functions. Consistent with its critical physiological significance, mutations in ITPR1 are associated with disease. Surprisingly, nearly all the disease-associated ITPR1 mutations characterized to date are loss of function. Despite the paucity of ITPR1 gain-of-function (GOF) mutations, enhanced ITPR1 function as a result of dysregulation by ITPR1 interacting proteins is thought to be associated with ataxia, learning and memory impairments, Alzheimer's disease (AD) progression, and chronic pain. However, direct evidence for the role of ITPR1 GOF in disease is lacking. To determine whether GOF in ITPR1 itself has pathological ramifications, we employed a newly developed mouse model expressing an ITPR1 mutation in the gating domain of the channel, D2594K, that markedly increased the channel's sensitivity to activation by IP3. Behavioral studies showed that the ITPR1-D2594K+/- mutant mice displayed motor deficits and reduced muscle strength. However, the ITPR1-D2594K+/- mutation did not significantly alter hippocampal learning and memory and did not change learning and memory impairments when crossed with the 5xFAD AD model mice. On the other hand, ITPR1-D2594K+/- mice exhibited increased sensitivity to thermal and mechanical stimulation compared to WT. Interestingly, R-carvedilol treatment attenuated the enhanced thermal and mechanical nociception in ITPR1-D2594K+/- mice. Thus, the ITPR1-D2594K+/- mutation in the channel's gating domain has a marked impact on motor movements and pain perception, but little effect on hippocampal learning and memory.
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Affiliation(s)
- Jinjing Yao
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada; Hotchkiss Brain Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, T2N 4N1, Canada
| | - Mingke Ni
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Shanshan Tian
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Bo Sun
- Medical School, Kunming University of Science and Technology, Kunming, China
| | - Ruiwu Wang
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - John Paul Estillore
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Thomas G Back
- Department of Chemistry, University of Calgary, Calgary, AB, Canada, T2N 1N4
| | - S R Wayne Chen
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada; Hotchkiss Brain Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, T2N 4N1, Canada.
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9
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Terry LE, Arige V, Neumann J, Wahl AM, Knebel TR, Chaffer JW, Malik S, Liston A, Humblet-Baron S, Bultynck G, Yule DI. Missense mutations in inositol 1,4,5-trisphosphate receptor type 3 result in leaky Ca 2+ channels and activation of store-operated Ca 2+ entry. iScience 2022; 25:105523. [PMID: 36444295 PMCID: PMC9700043 DOI: 10.1016/j.isci.2022.105523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/10/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
Mutations in all subtypes of the inositol 1,4,5-trisphosphate receptor Ca2+ release channel are associated with human diseases. In this report, we investigated the functionality of three neuropathy-associated missense mutations in IP3R3 (V615M, T1424M, and R2524C). The mutants only exhibited function when highly over-expressed compared to endogenous hIP3R3. All variants resulted in elevated basal cytosolic Ca2+ levels, decreased endoplasmic reticulum Ca2+ store content, and constitutive store-operated Ca2+ entry in the absence of any stimuli, consistent with a leaky IP3R channel pore. These variants differed in channel function; when stably over-expressed the R2524C mutant was essentially dead, V615M was poorly functional, and T1424M exhibited activity greater than that of the corresponding wild-type following threshold stimulation. These results demonstrate that a common feature of these mutations is decreased IP3R3 function. In addition, these mutations exhibit a novel phenotype manifested as a constitutively open channel, which inappropriately gates SOCE in the absence of stimulation.
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Affiliation(s)
- Lara E. Terry
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - Vikas Arige
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - Julika Neumann
- KU Leuven, Department of Microbiology and Immunology, Leuven, Belgium
| | - Amanda M. Wahl
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - Taylor R. Knebel
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - James W. Chaffer
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - Sundeep Malik
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - Adrian Liston
- KU Leuven, Department of Microbiology and Immunology, Leuven, Belgium
| | | | - Geert Bultynck
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Leuven, Belgium
| | - David I. Yule
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
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10
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Sun B, Ni M, Tian S, Guo W, Cai S, Sondergaard MT, Chen Y, Mu Y, Estillore JP, Wang R, Chen J, Overgaard MT, Fill M, Ramos-Franco J, Nyegaard M, Wayne Chen SR. A gain-of-function mutation in the ITPR1 gating domain causes male infertility in mice. J Cell Physiol 2022; 237:3305-3316. [PMID: 35621185 DOI: 10.1002/jcp.30783] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 04/16/2022] [Accepted: 05/06/2022] [Indexed: 11/10/2022]
Abstract
Inositol 1,4,5-trisphosphate receptor 1 (ITPR1) is an intracellular Ca2+ release channel critical for numerous cellular processes. Despite its ubiquitous physiological significance, ITPR1 mutations have thus far been linked to primarily movement disorders. Surprisingly, most disease-associated ITPR1 mutations generate a loss of function. This leaves our understanding of ITPR1-associated pathology oddly one-sided, as little is known about the pathological consequences of ITPR1 gain of function (GOF). To this end, we generated an ITPR1 gating domain mutation (D2594K) that substantially enhanced the inositol trisphosphate (IP3 )-sensitivity of ITPR1, and a mouse model expressing this ITPR1-D2594K+/- GOF mutation. We found that heterozygous ITPR1-D2594K+/- mutant mice exhibited male infertility, azoospermia, and acrosome loss. Furthermore, we functionally characterized a human ITPR1 variant V494I identified in the UK Biobank database as potentially associated with disorders of the testis. We found that the ITPR1-V494I variant significantly enhanced IP3 -induced Ca2+ release in HEK293 cells. Thus, ITPR1 hyperactivity may increase the risk of testicular dysfunction.
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Affiliation(s)
- Bo Sun
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada.,Laboratory of Molecular Pharmacology, Medical School, Kunming University of Science and Technology, Kunming, China
| | - Mingke Ni
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Shanshan Tian
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Wenting Guo
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Shitian Cai
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Mads T Sondergaard
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Yongxiang Chen
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Yongxin Mu
- Department of Medicine, University of California at San Diego, La Jolla, California, USA
| | - John P Estillore
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Ruiwu Wang
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Ju Chen
- Department of Medicine, University of California at San Diego, La Jolla, California, USA
| | - Michael T Overgaard
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Michael Fill
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, Illinois, USA
| | - Josefina Ramos-Franco
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, Illinois, USA
| | - Mette Nyegaard
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.,Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Sui Rong Wayne Chen
- Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada.,Department of Physiology and Biophysics, Rush University Medical Center, Chicago, Illinois, USA
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11
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Zachou A, Palaiologou D, Kanavakis E, Anagnostou E. Retrocollis as the cardinal feature in a de novo ITRP1 variant. Brain Dev 2022; 44:347-352. [PMID: 35148930 DOI: 10.1016/j.braindev.2022.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/15/2022] [Accepted: 01/17/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND ITPR1 gene encodes inositol 1,4,5-trisphosphate-receptor-type 1, a Ca2+ channel highly expressed in cerebellar Purkinje cells. ITPR1 gene variants, through a loss-of-function mechanism, have been found to be related with the manifestation of spinocerebellar ataxia (SCA) 15, an adult-onset slow progressive cerebellar ataxia, SCA 29, a rare non-progressive congenital cerebellar ataxia and Gillepsie syndrome (SCA 29 phenotype plus aniridia). They share an heterogeneity of additional phenotypic features while no genotype-phenotype correlation has ever been found. CASE REPORT Here we report the case of a boy with cerebellar ataxia who came to our clinic due to his cervical dystonia in the form of retrocollis. He presented an early-onset, non-progressive cerebellar ataxia, with cognitive impairment and delayed motor milestones. Whole exome sequencing (WES) revealed an heterozygous nucleotide variation, c.829A > C (p.Ser277Arg) in ITPR1 gene (NM_001168272.1), a de novo ITPR1 variant, as his parents came up with negative genetic testing. Due to his clinical presentation and genetic result, we came up with the diagnosis of SCA 29. CONCLUSION We described cervical dystonia as a phenotypic feature of ITPR1 related SCA 29, found in a new de novo ITPR1-variant.
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Affiliation(s)
- Athena Zachou
- Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, Greece.
| | - Danai Palaiologou
- Genesis Genoma Lab, Genetic Diagnosis, Clinical Genetics & Research, Athens, Greece
| | - Emmanouil Kanavakis
- Genesis Genoma Lab, Genetic Diagnosis, Clinical Genetics & Research, Athens, Greece
| | - Evangelos Anagnostou
- Department of Neurology, Eginition Hospital, National and Kapodistrian University of Athens, Greece
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12
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Woll KA, Van Petegem F. Calcium Release Channels: Structure and Function of IP3 Receptors and Ryanodine Receptors. Physiol Rev 2021; 102:209-268. [PMID: 34280054 DOI: 10.1152/physrev.00033.2020] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Ca2+-release channels are giant membrane proteins that control the release of Ca2+ from the endoplasmic and sarcoplasmic reticulum. The two members, ryanodine receptors (RyRs) and inositol-1,4,5-trisphosphate Receptors (IP3Rs), are evolutionarily related and are both activated by cytosolic Ca2+. They share a common architecture, but RyRs have evolved additional modules in the cytosolic region. Their massive size allows for the regulation by tens of proteins and small molecules, which can affect the opening and closing of the channels. In addition to Ca2+, other major triggers include IP3 for the IP3Rs, and depolarization of the plasma membrane for a particular RyR subtype. Their size has made them popular targets for study via electron microscopic methods, with current structures culminating near 3Å. The available structures have provided many new mechanistic insights int the binding of auxiliary proteins and small molecules, how these can regulate channel opening, and the mechanisms of disease-associated mutations. They also help scrutinize previously proposed binding sites, as some of these are now incompatible with the structures. Many questions remain around the structural effects of post-translational modifications, additional binding partners, and the higher-order complexes these channels can make in situ. This review summarizes our current knowledge about the structures of Ca2+-release channels and how this informs on their function.
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Affiliation(s)
- Kellie A Woll
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
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13
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Hasan G, Sharma A. Regulation of neuronal physiology by Ca2+ release through the IP3R. CURRENT OPINION IN PHYSIOLOGY 2020. [DOI: 10.1016/j.cophys.2020.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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14
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Rare CACNA1A mutations leading to congenital ataxia. Pflugers Arch 2020; 472:791-809. [DOI: 10.1007/s00424-020-02396-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 01/03/2023]
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15
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Inositol 1,4,5-Trisphosphate Receptors in Human Disease: A Comprehensive Update. J Clin Med 2020; 9:jcm9041096. [PMID: 32290556 PMCID: PMC7231134 DOI: 10.3390/jcm9041096] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/30/2020] [Accepted: 04/10/2020] [Indexed: 12/22/2022] Open
Abstract
Inositol 1,4,5-trisphosphate receptors (ITPRs) are intracellular calcium release channels located on the endoplasmic reticulum of virtually every cell. Herein, we are reporting an updated systematic summary of the current knowledge on the functional role of ITPRs in human disorders. Specifically, we are describing the involvement of its loss-of-function and gain-of-function mutations in the pathogenesis of neurological, immunological, cardiovascular, and neoplastic human disease. Recent results from genome-wide association studies are also discussed.
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16
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Roles for the Endoplasmic Reticulum in Regulation of Neuronal Calcium Homeostasis. Cells 2019; 8:cells8101232. [PMID: 31658749 PMCID: PMC6829861 DOI: 10.3390/cells8101232] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 10/01/2019] [Accepted: 10/03/2019] [Indexed: 02/06/2023] Open
Abstract
By influencing Ca2+ homeostasis in spatially and architecturally distinct neuronal compartments, the endoplasmic reticulum (ER) illustrates the notion that form and function are intimately related. The contribution of ER to neuronal Ca2+ homeostasis is attributed to the organelle being the largest reservoir of intracellular Ca2+ and having a high density of Ca2+ channels and transporters. As such, ER Ca2+ has incontrovertible roles in the regulation of axodendritic growth and morphology, synaptic vesicle release, and neural activity dependent gene expression, synaptic plasticity, and mitochondrial bioenergetics. Not surprisingly, many neurological diseases arise from ER Ca2+ dyshomeostasis, either directly due to alterations in ER resident proteins, or indirectly via processes that are coupled to the regulators of ER Ca2+ dynamics. In this review, we describe the mechanisms involved in the establishment of ER Ca2+ homeostasis in neurons. We elaborate upon how changes in the spatiotemporal dynamics of Ca2+ exchange between the ER and other organelles sculpt neuronal function and provide examples that demonstrate the involvement of ER Ca2+ dyshomeostasis in a range of neurological and neurodegenerative diseases.
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17
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Prole DL, Taylor CW. Structure and Function of IP 3 Receptors. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a035063. [PMID: 30745293 DOI: 10.1101/cshperspect.a035063] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Inositol 1,4,5-trisphosphate receptors (IP3Rs), by releasing Ca2+ from the endoplasmic reticulum (ER) of animal cells, allow Ca2+ to be redistributed from the ER to the cytosol or other organelles, and they initiate store-operated Ca2+ entry (SOCE). For all three IP3R subtypes, binding of IP3 primes them to bind Ca2+, which then triggers channel opening. We are now close to understanding the structural basis of IP3R activation. Ca2+-induced Ca2+ release regulated by IP3 allows IP3Rs to regeneratively propagate Ca2+ signals. The smallest of these regenerative events is a Ca2+ puff, which arises from the nearly simultaneous opening of a small cluster of IP3Rs. Ca2+ puffs are the basic building blocks for all IP3-evoked Ca2+ signals, but only some IP3 clusters, namely those parked alongside the ER-plasma membrane junctions where SOCE occurs, are licensed to respond. The location of these licensed IP3Rs may allow them to selectively regulate SOCE.
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Affiliation(s)
- David L Prole
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, United Kingdom
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, United Kingdom
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18
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Aberrant IP 3 receptor activities revealed by comprehensive analysis of pathological mutations causing spinocerebellar ataxia 29. Proc Natl Acad Sci U S A 2018; 115:12259-12264. [PMID: 30429331 DOI: 10.1073/pnas.1811129115] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Spinocerebellar ataxia type 29 (SCA29) is autosomal dominant congenital ataxia characterized by early-onset motor delay, hypotonia, and gait ataxia. Recently, heterozygous missense mutations in an intracellular Ca2+ channel, inositol 1,4,5-trisphosphate (IP3) receptor type 1 (IP3R1), were identified as a cause of SCA29. However, the functional impacts of these mutations remain largely unknown. Here, we determined the molecular mechanisms by which pathological mutations affect IP3R1 activity and Ca2+ dynamics. Ca2+ imaging using IP3R-null HeLa cells generated by genome editing revealed that all SCA29 mutations identified within or near the IP3-binding domain of IP3R1 completely abolished channel activity. Among these mutations, R241K, T267M, T267R, R269G, R269W, S277I, K279E, A280D, and E497K impaired IP3 binding to IP3R1, whereas the T579I and N587D mutations disrupted channel activity without affecting IP3 binding, suggesting that T579I and N587D compromise channel gating mechanisms. Carbonic anhydrase-related protein VIII (CA8) is an IP3R1-regulating protein abundantly expressed in cerebellar Purkinje cells and is a causative gene of congenital ataxia. The SCA29 mutation V1538M within the CA8-binding site of IP3R1 completely eliminated its interaction with CA8 and CA8-mediated IP3R1 inhibition. Furthermore, pathological mutations in CA8 decreased CA8-mediated suppression of IP3R1 by reducing protein stability and the interaction with IP3R1. These results demonstrated the mechanisms by which pathological mutations cause IP3R1 dysfunction, i.e., the disruption of IP3 binding, IP3-mediated gating, and regulation via the IP3R-modulatory protein. The resulting aberrant Ca2+ homeostasis may contribute to the pathogenesis of cerebellar ataxia.
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19
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Joseph SK, Young MP, Alzayady K, Yule DI, Ali M, Booth DM, Hajnóczky G. Redox regulation of type-I inositol trisphosphate receptors in intact mammalian cells. J Biol Chem 2018; 293:17464-17476. [PMID: 30228182 PMCID: PMC6231128 DOI: 10.1074/jbc.ra118.005624] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/09/2018] [Indexed: 12/31/2022] Open
Abstract
A sensitization of inositol 1,4,5-trisphosphate receptor (IP3R)-mediated Ca2+ release is associated with oxidative stress in multiple cell types. These effects are thought to be mediated by alterations in the redox state of critical thiols in the IP3R, but this has not been directly demonstrated in intact cells. Here, we utilized a combination of gel-shift assays with MPEG-maleimides and LC-MS/MS to monitor the redox state of recombinant IP3R1 expressed in HEK293 cells. We found that under basal conditions, ∼5 of the 60 cysteines are oxidized in IP3R1. Cell treatment with 50 μm thimerosal altered gel shifts, indicating oxidation of ∼20 cysteines. By contrast, the shifts induced by 0.5 mm H2O2 or other oxidants were much smaller. Monitoring of biotin-maleimide attachment to IP3R1 by LC-MS/MS with 71% coverage of the receptor sequence revealed modification of two cytosolic (Cys-292 and Cys-1415) and two intraluminal cysteines (Cys-2496 and Cys-2533) under basal conditions. The thimerosal treatment modified an additional eleven cysteines, but only three (Cys-206, Cys-767, and Cys-1459) were consistently oxidized in multiple experiments. H2O2 also oxidized Cys-206 and additionally oxidized two residues not modified by thimerosal (Cys-214 and Cys-1397). Potentiation of IP3R channel function by oxidants was measured with cysteine variants transfected into a HEK293 IP3R triple-knockout cell line, indicating that the functionally relevant redox-sensitive cysteines are predominantly clustered within the N-terminal suppressor domain of IP3R. To our knowledge, this study is the first that has used proteomic methods to assess the redox state of individual thiols in IP3R in intact cells.
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Affiliation(s)
- Suresh K Joseph
- From the MitoCare Center, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107,
| | - Michael P Young
- From the MitoCare Center, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Kamil Alzayady
- the Department of Pharmacology & Physiology, University of Rochester, Rochester, New York 14642, and
| | - David I Yule
- the Department of Pharmacology & Physiology, University of Rochester, Rochester, New York 14642, and
| | - Mehboob Ali
- the Center for Perinatal Research, Research Institute, Nationwide Children's Hospital, Columbus, Ohio 43205
| | - David M Booth
- From the MitoCare Center, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - György Hajnóczky
- From the MitoCare Center, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
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20
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Pathophysiological consequences of isoform-specific IP 3 receptor mutations. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1707-1717. [PMID: 29906486 DOI: 10.1016/j.bbamcr.2018.06.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 06/06/2018] [Accepted: 06/11/2018] [Indexed: 12/11/2022]
Abstract
Ca2+ signaling governs a diverse range of cellular processes and, as such, is subject to tight regulation. A main component of the complex intracellular Ca2+-signaling network is the inositol 1,4,5-trisphosphate (IP3) receptor (IP3R), a tetrameric channel that mediates Ca2+ release from the endoplasmic reticulum (ER) in response to IP3. IP3R function is controlled by a myriad of factors, such as Ca2+, ATP, kinases and phosphatases and a plethora of accessory and regulatory proteins. Further complexity in IP3R-mediated Ca2+ signaling is the result of the existence of three main isoforms (IP3R1, IP3R2 and IP3R3) that display distinct functional characteristics and properties. Despite their abundant and overlapping expression profiles, IP3R1 is highly expressed in neurons, IP3R2 in cardiomyocytes and hepatocytes and IP3R3 in rapidly proliferating cells as e.g. epithelial cells. As a consequence, dysfunction and/or dysregulation of IP3R isoforms will have distinct pathophysiological outcomes, ranging from neurological disorders for IP3R1 to dysfunctional exocrine tissues and autoimmune diseases for IP3R2 and -3. Over the past years, several IP3R mutations have surfaced in the sequence analysis of patient-derived samples. Here, we aimed to provide an integrative overview of the clinically most relevant mutations for each IP3R isoform and the subsequent molecular mechanisms underlying the etiology of the disease.
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21
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Ca 2+ signaling and spinocerebellar ataxia. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1733-1744. [PMID: 29777722 DOI: 10.1016/j.bbamcr.2018.05.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/07/2018] [Accepted: 05/09/2018] [Indexed: 11/22/2022]
Abstract
Spinocerebellar ataxia (SCA) is a neural disorder, which is caused by degenerative changes in the cerebellum. SCA is primarily characterized by gait ataxia, and additional clinical features include nystagmus, dysarthria, tremors and cerebellar atrophy. Forty-four hereditary SCAs have been identified to date, along with >35 SCA-associated genes. Despite the great diversity and distinct functionalities of the SCA-related genes, accumulating evidence supports the occurrence of a common pathophysiological event among several hereditary SCAs. Altered calcium (Ca2+) homeostasis in the Purkinje cells (PCs) of the cerebellum has been proposed as a possible pathological SCA trigger. In support of this, signaling events that are initiated from or lead to aberrant Ca2+ release from the type 1 inositol 1,4,5-trisphosphate receptor (IP3R1), which is highly expressed in cerebellar PCs, seem to be closely associated with the pathogenesis of several SCA types. In this review, we summarize the current research on pathological hereditary SCA events, which involve altered Ca2+ homeostasis in PCs, through IP3R1 signaling.
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22
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Bushart DD, Shakkottai VG. Ion channel dysfunction in cerebellar ataxia. Neurosci Lett 2018; 688:41-48. [PMID: 29421541 DOI: 10.1016/j.neulet.2018.02.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 02/02/2018] [Indexed: 12/31/2022]
Abstract
Cerebellar ataxias constitute a heterogeneous group of disorders that result in impaired speech, uncoordinated limb movements, and impaired balance, often ultimately resulting in wheelchair confinement. Motor dysfunction in ataxia can be attributed to dysfunction and degeneration of neurons in the cerebellum and its associated pathways. Recent work has suggested the importance of cerebellar neuronal dysfunction resulting from mutations in specific ion-channels that regulate membrane excitability in the pathogenesis of cerebellar ataxia in humans. Importantly, even in ataxias not directly due to ion-channel mutations, transcriptional changes resulting in ion-channel dysfunction are tied to motor dysfunction and degeneration in models of disease. In this review, we describe the role that ion-channel dysfunction plays in a variety of cerebellar ataxias, and postulate that a potential therapeutic strategy that targets specific ion-channels exists for cerebellar ataxia.
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Affiliation(s)
- David D Bushart
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor MI, USA
| | - Vikram G Shakkottai
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor MI, USA; Department of Neurology, University of Michigan, 4009 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI, 48109, USA.
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23
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Egorova PA, Bezprozvanny IB. Inositol 1,4,5-trisphosphate receptors and neurodegenerative disorders. FEBS J 2018; 285:3547-3565. [PMID: 29253316 DOI: 10.1111/febs.14366] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/27/2017] [Accepted: 12/12/2017] [Indexed: 12/15/2022]
Abstract
The inositol 1,4,5-trisphosphate receptor (IP3 R) is an intracellular ion channel that mediates the release of calcium ions from the endoplasmic reticulum. It plays a role in basic biological functions, such as cell division, differentiation, fertilization and cell death, and is involved in developmental processes including learning, memory and behavior. Deregulation of neuronal calcium signaling results in disturbance of cell homeostasis, synaptic loss and dysfunction, eventually leading to cell death. Three IP3 R subtypes have been identified in mammalian cells and the predominant isoform in neurons is IP3 R type 1. Dysfunction of IP3 R type 1 may play a role in the pathogenesis of certain neurodegenerative diseases as enhanced activity of the IP3 R was observed in models of Huntington's disease, spinocerebellar ataxias and Alzheimer's disease. These results suggest that IP3 R-mediated signaling is a potential target for treatment of these disorders. In this review we discuss the structure, functions and regulation of the IP3 R in healthy neurons and in conditions of neurodegeneration.
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Affiliation(s)
- Polina A Egorova
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St Petersburg, Russia
| | - Ilya B Bezprozvanny
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St Petersburg, Russia.,Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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