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Kuwashima Y, Yanagawa M, Maekawa M, Abe M, Sako Y, Arita M. TRPV4-dependent Ca 2+ influx determines cholesterol dynamics at the plasma membrane. Biophys J 2024; 123:867-884. [PMID: 38433447 PMCID: PMC10995426 DOI: 10.1016/j.bpj.2024.02.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 12/01/2023] [Accepted: 02/29/2024] [Indexed: 03/05/2024] Open
Abstract
The activities of the transient receptor potential vanilloid 4 (TRPV4), a Ca2+-permeable nonselective cation channel, are controlled by its surrounding membrane lipids (e.g., cholesterol, phosphoinositides). The transmembrane region of TRPV4 contains a cholesterol recognition amino acid consensus (CRAC) motif and its inverted (CARC) motif located in the plasmalemmal cytosolic leaflet. TRPV4 localizes in caveolae, a bulb-shaped cholesterol-rich domain at the plasma membrane. Here, we visualized the spatiotemporal interactions between TRPV4 and cholesterol at the plasma membrane in living cells by dual-color single-molecule imaging using total internal reflection fluorescence microscopy. To this aim, we labeled cholesterol at the cytosolic leaflets of the plasma membrane using a cholesterol biosensor, D4H. Our single-molecule tracking analysis showed that the TRPV4 molecules colocalize with D4H-accessible cholesterol molecules mainly in the low fluidity membrane domains in which both molecules are highly clustered. Colocalization of TRPV4 and D4H-accessible cholesterol was observed both inside and outside of caveolae. Agonist-evoked TRPV4 activation remarkably decreased colocalization probability and association rate between TRPV4 and D4H-accessible cholesterol molecules. Interestingly, upon TRPV4 activation, the particle density of D4H-accessible cholesterol molecules was decreased and the D4H-accessible cholesterol molecules in the fast-diffusing state were increased at the plasma membrane. The introduction of skeletal dysplasia-associated R616Q mutation into the CRAC/CARC motif of TRPV4, which reduced the interaction with cholesterol clusters, could not alter the D4H-accessible cholesterol dynamics. Mechanistically, TRPV4-mediated Ca2+ influx and the C-terminal calmodulin-binding site of TRPV4 are essential for modulating the plasmalemmal D4H-accessible cholesterol dynamics. We propose that TRPV4 remodels its surrounding plasmalemmal environment by manipulating cholesterol dynamics through Ca2+ influx.
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Affiliation(s)
- Yutaro Kuwashima
- Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan; Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama, Japan
| | - Masataka Yanagawa
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama, Japan; Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Masashi Maekawa
- Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan; Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences (IMS), Kanagawa, Japan
| | - Mitsuhiro Abe
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN Cluster for Pioneering Research (CPR), Saitama, Japan.
| | - Makoto Arita
- Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan; Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences (IMS), Kanagawa, Japan; Cellular and Molecular Epigenetics Laboratory, Graduate School of Medical Life Science, Yokohama City University, Kanagawa, Japan; Human Biology-Microbiome-Quantum Research Center (WPI-Bio2Q), Keio University, Tokyo, Japan.
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Lugo E, Graulau E, Ramos Cortes E, Carlo S, Ramírez N. Homozygous TRPV4 Mutation Broadens the Phenotypic Spectrum of Congenital Spinal Muscular Atrophy and Arthrogryposis: A Case Report. Cureus 2023; 15:e43413. [PMID: 37706131 PMCID: PMC10495693 DOI: 10.7759/cureus.43413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2023] [Indexed: 09/15/2023] Open
Abstract
Transient receptor potential vanilloid 4 (TRPV4) mutations are known to cause inherited axonal neuropathies and skeletal dysplasia. TRPV4 mutations are associated with distal hereditary motor neuropathies (dHMN), which distinctly involve motor deficits. A 1 ½-year-old boy presented at the clinic with diminished lower limb movement and ambulatory limitations. The patient was born with bilateral knee arthrogryposis and bilateral talipes equinovarus, which required surgical intervention. A gross neurologic exam was unremarkable, with normal vision and hearing. A bone survey radiograph showed no evidence of skeletal dysplasia. Genetic tests revealed a homozygous mutation in the TRPV4 gene (c.281C>T; p.S94L), leading to the diagnosis of congenital spinal muscular atrophy and arthrogryposis (CSMAA). Hence, this presents the first case of CSMAA caused by a TRPV4 mutation (p.S94L), with a different presentation from the one previously described in the literature, thus broadening the phenotypic variability and clinical spectrum of TRPV4 mutations.
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Affiliation(s)
- Elyette Lugo
- Medicine, Universidad Central del Caribe, Bayamón, PRI
| | - Eric Graulau
- Medicine, Ponce Health Sciences University, Ponce, PRI
| | - Edwardo Ramos Cortes
- Physical Medicine and Rehabilitation, University of Puerto Rico, Medical Sciences Campus, San Juan, PRI
| | - Simón Carlo
- Biochemistry/Pediatrics/Psychiatry, Ponce Health Sciences University, Ponce, PRI
- Pediatrics, Mayagüez Medical Center, Mayagüez, PRI
| | - Norman Ramírez
- Medicine, Universidad Central del Caribe, Bayamón, PRI
- Pediatric Orthopedic Surgery, Mayagüez Medical Center, Mayagüez, PRI
- Medicine, Ponce Health Sciences University, Ponce, PRI
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3
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Uzman CY, Çankaya T, Güleryüz H, Ülgenalp A, Bozkaya ÖG. Spondyloepimetaphyseal dysplasia-Maroteaux type due to dominant TRPV4 mutation: expanding the phenotype with a case report. Skeletal Radiol 2023; 52:115-118. [PMID: 35776137 DOI: 10.1007/s00256-022-04105-6] [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: 05/04/2022] [Revised: 06/17/2022] [Accepted: 06/20/2022] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Dominant pathogenic mutations in the TRPV4 gene give rise to a wide spectrum of abnormal phenotypes, including bone dysplasia as well as spinal muscular atrophy and hereditary motor and sensory neuropathy. Spondyloepimetaphyseal dysplasias (SEMDs) are autosomal dominant skeletal dysplasias characterized by mild epiphyseal dysplasia, flared metaphyses, prominent joints, spondyler dysplasia, and brachydactyly with various carpal, metacarpal, and finger malformations. CASE PRESENTATION We present a boy who has the clinical and radiological signs of SEMD-M with a dominant TRPV4 mutation. He also has some striking findings that have not been seen in these patients before, and they may be able to provide assistance to medical professionals in the process of diagnosis.These include a shorter distance between his lumbar vertebrae, congenital contractures, and an arachnoid cyst.
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Affiliation(s)
- Ceren Yılmaz Uzman
- Faculty of Medicine, Department of Pediatrics, Division of Pediatric Genetics, Dokuz Eylul University, İnciraltı mahallesi Mithatpaşa street no: 56, Balçova, İzmir, 35330, Turkey.
| | - Tufan Çankaya
- Faculty of Medicine, Department of Medical Genetics, Dokuz Eylul University, İzmir, Turkey
| | - Handan Güleryüz
- Faculty of Medicine, Department of Radiology, Division of Pediatric Radiology, Dokuz Eylul University School of Medicine, Dokuz Eylul University, Izmir, Turkey
| | - Ayfer Ülgenalp
- Faculty of Medicine, Department of Pediatrics, Division of Pediatric Genetics, Dokuz Eylul University, İnciraltı mahallesi Mithatpaşa street no: 56, Balçova, İzmir, 35330, Turkey
- Faculty of Medicine, Department of Medical Genetics, Dokuz Eylul University, İzmir, Turkey
| | - Özlem Giray Bozkaya
- Faculty of Medicine, Department of Pediatrics, Division of Pediatric Genetics, Dokuz Eylul University, İnciraltı mahallesi Mithatpaşa street no: 56, Balçova, İzmir, 35330, Turkey
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Windswept Deformity a Disease or a Symptom? A Systematic Review on the Aetiologies and Hypotheses of Simultaneous Genu Valgum and Varum in Children. CHILDREN 2022; 9:children9050703. [PMID: 35626880 PMCID: PMC9140164 DOI: 10.3390/children9050703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 05/01/2022] [Accepted: 05/03/2022] [Indexed: 11/17/2022]
Abstract
Objective: The objective of this study is to create an overview of the possible aetiologies of windswept deformity and to emphasize the points of attention when presented with a case. Methods: A systematic search according to the PRISMA statement was conducted using PubMed, African Journals Online, Cochrane, Embase, Google Scholar, and Web of Science. Articles investigating the aetiology of windswept deformity at the knee in children, and articles with windswept deformity as an ancillary finding were included. The bibliographic search was limited to English-language articles only. The level of evidence and methodological appraisal were assessed. Results: Forty-five articles discussing the aetiology of windswept deformity were included. A variety of aetiologies can be brought forward. These can be divided into the following groups: ‘Rickets and other metabolic disorders’, ‘skeletal dysplasias and other genetic disorders’, ‘trauma’ and ‘descriptive articles without specific underlying disorder’. With rickets being the largest group. Interestingly, in the group without a specific underlying disorder, all patients were from African descent, being otherwise healthy and presented with windswept deformity between two and three years of age. Conclusion: We have presented an overview that may help identify the underlying disorder in children with windswept deformity. A step-by-step guide for clinicians who see a child with windswept deformity is provided. Even though, according to the Oxford level of evidence, most articles have a low level of evidence.
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TRPing to the Point of Clarity: Understanding the Function of the Complex TRPV4 Ion Channel. Cells 2021; 10:cells10010165. [PMID: 33467654 PMCID: PMC7830798 DOI: 10.3390/cells10010165] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 02/07/2023] Open
Abstract
The transient receptor potential vanilloid 4 channel (TRPV4) belongs to the mammalian TRP superfamily of cation channels. TRPV4 is ubiquitously expressed, activated by a disparate array of stimuli, interacts with a multitude of proteins, and is modulated by a range of post-translational modifications, the majority of which we are only just beginning to understand. Not surprisingly, a great number of physiological roles have emerged for TRPV4, as have various disease states that are attributable to the absence, or abnormal functioning, of this ion channel. This review will highlight structural features of TRPV4, endogenous and exogenous activators of the channel, and discuss the reported roles of TRPV4 in health and disease.
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The Zinc-Finger Domain Containing Protein ZC4H2 Interacts with TRPV4, Enhancing Channel Activity and Turnover at the Plasma Membrane. Int J Mol Sci 2020; 21:ijms21103556. [PMID: 32443528 PMCID: PMC7278933 DOI: 10.3390/ijms21103556] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 02/07/2023] Open
Abstract
The Ca2+-permeable Transient Receptor Potential channel vanilloid subfamily member 4 (TRPV4) is involved in a broad range of physiological processes, including the regulation of systemic osmotic pressure, bone resorption, vascular tone, and bladder function. Mutations in the TRPV4 gene are the cause of a spectrum of inherited diseases (or TRPV4-pathies), which include skeletal dysplasias, arthropathies, and neuropathies. There is little understanding of the pathophysiological mechanisms underlying these variable disease phenotypes, but it has been hypothesized that disease-causing mutations affect interaction with regulatory proteins. Here, we performed a mammalian protein-protein interaction trap (MAPPIT) screen to identify proteins that interact with the cytosolic N terminus of human TRPV4, a region containing the majority of disease-causing mutations. We discovered the zinc-finger domain-containing protein ZC4H2 as a TRPV4-interacting protein. In heterologous expression experiments, we found that ZC4H2 increases both the basal activity of human TRPV4 as well as Ca2+ responses evoked by ligands or hypotonic cell swelling. Using total internal reflection fluorescence (TIRF) microscopy, we further showed that ZC4H2 accelerates TRPV4 turnover at the plasma membrane. Overall, these data demonstrate that ZC4H2 is a positive modulator of TRPV4, and suggest a link between TRPV4 and ZC4H2-associated rare disorders, which have several neuromuscular symptoms in common with TRPV4-pathies.
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Nishimura H, Kawasaki M, Tsukamoto M, Menuki K, Suzuki H, Matsuura T, Baba K, Motojima Y, Fujitani T, Ohnishi H, Yamanaka Y, Kosugi K, Okada Y, Tokuda K, Tajima T, Yoshioka T, Okimoto N, Ueta Y, Sakai A. Transient receptor potential vanilloid 1 and 4 double knockout leads to increased bone mass in mice. Bone Rep 2020; 12:100268. [PMID: 32373678 PMCID: PMC7191598 DOI: 10.1016/j.bonr.2020.100268] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 03/23/2020] [Accepted: 04/06/2020] [Indexed: 12/19/2022] Open
Abstract
Calcium balance is important in bone homeostasis. The transient receptor potential vanilloid (TRPV) channel is a nonselective cation channel permeable to calcium and is activated by various physiological and pharmacological stimuli. TRPV1 and TRPV4, in particular, have important roles in intracellular Ca2+ signaling and extracellular calcium homeostasis in bone cells. TRPV1 and TRPV4 separately mediate osteoclast and osteoblast differentiation, and deficiency in any of these channels leads to increased bone mass. However, it remains unknown whether bone mass increases in the absence of both TRPV1 and TRPV4. In this study, we used TRPV1 and TRPV4 double knockout (DKO) mice to evaluate their bone mass in vivo, and osteoclast and osteoblast differentiation in vitro. Our results showed that DKO mice and wild type (WT) mice had no significant difference in body weight and femur length. However, the results of dual-energy X-ray absorption, microcomputed tomography, and bone histomorphometry clearly showed that DKO mice had higher bone mass than WT mice. Furthermore, DKO mice had less multinucleated osteoclasts and had lower bone resorption. In addition, the results of cell culture using flushed bone marrow from mouse femurs and tibias showed that osteoclast differentiation was suppressed, whereas osteoblast differentiation was promoted in DKO mice. In conclusion, our results suggest that the increase in bone mass in DKO mice was induced not only by the suppression of osteoclast differentiation and activity but also by the augmentation of osteoblast differentiation and activity. Our findings reveal that both the single deficiency of TRPVs and the concurrent deficiency of TRPVs result in an increase in bone mass. Furthermore, our data showed that DKO mice and single KO mice had varying approaches to osteoclast and osteoblast differentiation in vitro, and therefore, it is important to conduct further studies on TRPVs regarding the increase in bone mass to explore not only individual but also a combination of TRPVs. Knockout of either TRPV1 or TRPV4 results in increased bone mass in mice. This study evaluates the effects of TRPV1 and TRPV4 double knockout (DKO) in mice. Concurrent TRPV1 and TRPV4 deficiency increases mouse bone mass. TRPV1 and TRPV4 DKO suppresses osteoclast differentiation and activity. TRPV1 and TRPV4 DKO enhances osteoblast differentiation and activity.
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Key Words
- ALP, alkaline phosphatase
- BMD, bone mineral density
- BMSCs, bone marrow mesenchymal stem cells
- Bone histomorphometry
- CB, cannabinoid
- CT, computed tomography
- Cell culture
- DKO, double knock out
- DXA, dual-energy X-ray absorption
- MNCs, multinucleated cells
- Micro-CT
- Osteogenesis
- PCR, polymerase chain reaction
- POc, preosteoclast
- Preosteoclast
- RANK, receptor activator of nuclear factor-kappa B
- RANKL, receptor activator of nuclear factor-kappa B ligand
- TRACP, tartrate-resistant acid phosphatase
- TRPV, transient receptor potential vanilloid
- Transient receptor potential vanilloid
- V1KO, TRPV1 knock out
- V4KO, TRPV4 knock out
- WT, wild type
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Affiliation(s)
- Haruki Nishimura
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Makoto Kawasaki
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Manabu Tsukamoto
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Kunitaka Menuki
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Hitoshi Suzuki
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Takanori Matsuura
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Kazuhiko Baba
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Yasuhito Motojima
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Teruaki Fujitani
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Hideo Ohnishi
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Yoshiaki Yamanaka
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Kenji Kosugi
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Yasuaki Okada
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Kotaro Tokuda
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Takafumi Tajima
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Toru Yoshioka
- Department of Orthopaedics, Shimura Hospital, 3-13 Funairimachi Naka-ku, Hiroshima 730-0841, Japan
| | - Nobukazu Okimoto
- Okimoto Clinic, 185-4 Yutakamachikubi, Kure, Hiroshima 734-0304, Japan
| | - Yoichi Ueta
- Department of Physiology, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Akinori Sakai
- Department of Orthopaedic Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
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Gomes CC, Diniz MG, Bastos VC, Bernardes VF, Gomez RS. Making sense of giant cell lesions of the jaws (GCLJ): lessons learned from next-generation sequencing. J Pathol 2019; 250:126-133. [PMID: 31705763 DOI: 10.1002/path.5365] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/16/2019] [Accepted: 11/06/2019] [Indexed: 01/09/2023]
Abstract
Next-generation sequencing has revealed mutations in several bone-related lesions and was recently used to uncover the genetic basis of giant cell lesions of the jaws (GCLJ). Consistent with their benign nature, GCLJ show a low tumor mutation burden. They also harbor somatic, heterozygous, mutually exclusive mutations in TRPV4, KRAS, or FGFR1. These signature mutations occur only in a subset of lesional cells, suggesting the existence of a 'landscaping effect', with mutant cells inducing abnormal accumulation of non-mutant cells that form the tumor mass. Osteoclast-rich lesions with histological similarities to GCLJ can occur in the jaws sporadically or in association with genetically inherited syndromes. Based on recent results, the pathogenesis of a subgroup of sporadic GCLJ seems closely related to non-ossifying fibroma of long bones, with both lesions sharing MAPK pathway-activating mutations. In this review, we extrapolate from these recent findings to contextualize GCLJ genetics and we highlight the therapeutic implications of this new information. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Carolina C Gomes
- Department of Pathology, Biological Sciences Institute, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Marina G Diniz
- Department of Pathology, Biological Sciences Institute, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Victor C Bastos
- Department of Pathology, Biological Sciences Institute, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Vanessa F Bernardes
- Department of Pathology, Biological Sciences Institute, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Ricardo S Gomez
- Department of Oral Surgery and Pathology, Faculty of Dentistry, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
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Teng J, Anishkin A, Kung C, Blount P. Human mutations highlight an intersubunit cation-π bond that stabilizes the closed but not open or inactivated states of TRPV channels. Proc Natl Acad Sci U S A 2019; 116:9410-9416. [PMID: 31010928 PMCID: PMC6511060 DOI: 10.1073/pnas.1820673116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
An adequate response of a living cell to the ever-changing environment requires integration of numerous sensory inputs. In many cases, it can be achieved even at the level of a single receptor molecule. Polymodal transient receptor potential (TRP) channels have been shown to integrate mechanical, chemical, electric, and thermal stimuli. Inappropriate gating can lead to pathologies. Among the >60 known TRP vanilloid subfamily (V) 4 mutations that interfere with bone development are Y602C or R616Q at the S4-S5 linker. A cation-π bond between the conservative residues Y602 and R616 of neighboring subunits appears likely in many homologous channel structures in a closed state. Our experiments with TRPV4 mutants indicate that the resting-closed state remains stable while the bond is substituted by a salt bridge or disulfide bond, whereas disruption of the contact by mutations like Y602C or R616Q produces gain-of-function phenotypes when TRPV4 is heterologously expressed in the Xenopus oocyte or yeast. Our data indicate that the Y602-R616 cation-π interactions link the four S4-S5 linker helices together, forming a girdle backing the closed gate. Analogous cation-π bonds and the girdle are seen in many closed TRP channel structures. This girdle is not observed in the cryo-EM structure of amphibian TRPV4 (Protein Data Bank ID code 6BBJ), which appears to be in a different impermeable state-we hypothesize this is the inactivated state.
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Affiliation(s)
- Jinfeng Teng
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Andriy Anishkin
- Department of Biology, University of Maryland, College Park, MD 20742;
| | - Ching Kung
- Laboratory of Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706;
- Department of Genetics, University of Wisconsin-Madison, Madison, WI 53706
| | - Paul Blount
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390;
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10
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Graversen L, Haagerup A, Andersen BN, Petersen KK, Gjørup V, Gudmundsdottir G, Vogel I, Gregersen PA. Novel TRPV4 variant causes a severe form of metatropic dysplasia. Clin Case Rep 2018; 6:1774-1778. [PMID: 30214761 PMCID: PMC6132144 DOI: 10.1002/ccr3.1598] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 04/06/2018] [Accepted: 04/12/2018] [Indexed: 01/19/2023] Open
Abstract
We present a girl born with a frontal bossing, short neck, bell-shaped thorax, short limbs with prominent joints, and a tail-like coccygeal appendage. Genetic screening of TRPV4 identified a novel de novo heterozygous missense variant. We believe the variant causes the severe form of metatropic dysplasia in this patient.
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Affiliation(s)
- Lise Graversen
- Pediatrics and Adolescent MedicineCentre for Rare DiseasesAarhus University HospitalAarhusDenmark
- Department of Clinical GeneticsAarhus University HospitalAarhusDenmark
| | - Annette Haagerup
- NIDO|danmarkWest Danish HospitalHerningDenmark
- Institute of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Brian N. Andersen
- Pediatrics and Adolescent MedicineCentre for Rare DiseasesAarhus University HospitalAarhusDenmark
| | | | - Vibike Gjørup
- Department of Gynaecology and ObstetricsAarhus University HospitalAarhusDenmark
| | | | - Ida Vogel
- Department of Clinical GeneticsAarhus University HospitalAarhusDenmark
| | - Pernille A. Gregersen
- Pediatrics and Adolescent MedicineCentre for Rare DiseasesAarhus University HospitalAarhusDenmark
- Department of Clinical GeneticsAarhus University HospitalAarhusDenmark
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11
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Deng Z, Paknejad N, Maksaev G, Sala-Rabanal M, Nichols CG, Hite RK, Yuan P. Cryo-EM and X-ray structures of TRPV4 reveal insight into ion permeation and gating mechanisms. Nat Struct Mol Biol 2018; 25:252-260. [PMID: 29483651 DOI: 10.1038/s41594-018-0037-5] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/26/2018] [Indexed: 12/15/2022]
Abstract
The transient receptor potential (TRP) channel TRPV4 participates in multiple biological processes, and numerous TRPV4 mutations underlie several distinct and devastating diseases. Here we present the cryo-EM structure of Xenopus tropicalis TRPV4 at 3.8-Å resolution. The ion-conduction pore contains an intracellular gate formed by the inner helices, but lacks any extracellular gate in the selectivity filter, as observed in other TRPV channels. Anomalous X-ray diffraction analyses identify a single ion-binding site in the selectivity filter, thus explaining TRPV4 nonselectivity. Structural comparisons with other TRP channels and distantly related voltage-gated cation channels reveal an unprecedented, unique packing interface between the voltage-sensor-like domain and the pore domain, suggesting distinct gating mechanisms. Moreover, our structure begins to provide mechanistic insights to the large set of pathogenic mutations, offering potential opportunities for drug development.
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Affiliation(s)
- Zengqin Deng
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Navid Paknejad
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Grigory Maksaev
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Monica Sala-Rabanal
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Richard K Hite
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Peng Yuan
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA. .,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA.
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12
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Genes uniquely expressed in human growth plate chondrocytes uncover a distinct regulatory network. BMC Genomics 2017; 18:983. [PMID: 29262782 PMCID: PMC5738906 DOI: 10.1186/s12864-017-4378-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 12/11/2017] [Indexed: 01/05/2023] Open
Abstract
Background Chondrogenesis is the earliest stage of skeletal development and is a highly dynamic process, integrating the activities and functions of transcription factors, cell signaling molecules and extracellular matrix proteins. The molecular mechanisms underlying chondrogenesis have been extensively studied and multiple key regulators of this process have been identified. However, a genome-wide overview of the gene regulatory network in chondrogenesis has not been achieved. Results In this study, employing RNA sequencing, we identified 332 protein coding genes and 34 long non-coding RNA (lncRNA) genes that are highly selectively expressed in human fetal growth plate chondrocytes. Among the protein coding genes, 32 genes were associated with 62 distinct human skeletal disorders and 153 genes were associated with skeletal defects in knockout mice, confirming their essential roles in skeletal formation. These gene products formed a comprehensive physical interaction network and participated in multiple cellular processes regulating skeletal development. The data also revealed 34 transcription factors and 11,334 distal enhancers that were uniquely active in chondrocytes, functioning as transcriptional regulators for the cartilage-selective genes. Conclusions Our findings revealed a complex gene regulatory network controlling skeletal development whereby transcription factors, enhancers and lncRNAs participate in chondrogenesis by transcriptional regulation of key genes. Additionally, the cartilage-selective genes represent candidate genes for unsolved human skeletal disorders. Electronic supplementary material The online version of this article (10.1186/s12864-017-4378-y) contains supplementary material, which is available to authorized users.
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13
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Lim YJ, Lee HR, Kim OH, Cho TJ, Park KB. Autosomal dominant brachyolmia: transient metaphyseal striations. Skeletal Radiol 2017; 46:1297-1300. [PMID: 28601949 DOI: 10.1007/s00256-017-2684-8] [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: 03/28/2017] [Revised: 05/15/2017] [Accepted: 05/22/2017] [Indexed: 02/02/2023]
Abstract
We report transient proximal and distal femoral metaphyseal striations that have not previously been described in autosomal dominant brachyolmia. The pelvis/hip radiograph of a 13-year-old boy demonstrated bilaterally symmetrical proximal femoral metaphyseal vertical striations. Additional vertical striations were also observed at the distal femur and proximal tibia metaphysis. Radiography of the thoracolumbar spine demonstrated platyspondyly with irregular endplates and overfaced pedicles. TRPV4 mutations were confirmed in this patient. Similar proximal femoral metaphyseal vertical striations were noted in the patient's sibling. Those streaks disappeared on the follow-up radiographs, and we considered it a unique radiologic finding transiently observed in autosomal dominant brachyolmia.
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Affiliation(s)
- Yun-Jung Lim
- Department of Radiology, Inje University Haeundae Paik Hospital, 875, Haeun-daero, Haeundae-gu, Busan, 48108, South Korea
| | - Hye-Ran Lee
- Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 03080, South Korea
| | - Ok-Hwa Kim
- Department of Radiology, Woorisoa Children's Hospital, 15, Saemal-ro, Guro-gu, Seoul, 08291, South Korea
| | - Tae-Joon Cho
- Division of Pediatric Orthopaedics, Seoul National University Children's Hospital, 101, Daehak-ro, Jongno-gu, Seoul, 03080, South Korea
| | - Kun-Bo Park
- Department of Orthopaedic Surgery, Yonsei University College of Medicine, Severance Children's Hospital, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.
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14
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Bieganski T, Beighton P, Lukaszewski M, Bik K, Kuszel L, Wasilewska E, Kozlowski K, Czarny-Ratajczak M. SMD Kozlowski type caused by p.Arg594His substitution in TRPV4 reveals abnormal ossification and notochordal remnants in discs and vertebrae. Eur J Med Genet 2017; 60:509-516. [PMID: 28687525 DOI: 10.1016/j.ejmg.2017.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 06/09/2017] [Accepted: 07/03/2017] [Indexed: 10/19/2022]
Abstract
Spondylometaphyseal dysplasia Kozlowski type (SMDK) is a monogenic disorder within the TRPV4 dysplasia spectrum and has characteristic spinal and metaphyseal changes. We report skeletal MR imaging in a two-year-old patient who manifested typical clinical and radiographic features of SMDK. The diagnosis was confirmed by molecular analysis which revealed a mutation NM_021625.4:c.1781G > A - p.(Arg594His) in exon 11 of the TRPV4 gene. We have documented abnormalities in endochondral formation of the long and short tubular bones as well as round bones of the wrists and feet. The vertebral bodies had increased thickness of hyaline cartilage which enveloped ossification centers. The vertebrae and discs also had abnormalities in size, shape and structure. These anomalies were most likely the consequence of notochordal remnants presence within the intervertebral discs and in the vertebral bodies. The advantages of MR imaging in bone dysplasias caused by TRPV4 mutations are emphasized in this article.
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Affiliation(s)
- Tadeusz Bieganski
- Department of Diagnostic Imaging, Polish Mother(')s Memorial Hospital - Research Institute, Lodz, Poland
| | - Peter Beighton
- Division of Human Genetics, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Maciej Lukaszewski
- Department of Diagnostic Imaging, Polish Mother(')s Memorial Hospital - Research Institute, Lodz, Poland
| | - Krzysztof Bik
- Department of Orthopaedics, Polish Mother(')s Memorial Hospital - Research Institute, Lodz, Poland
| | - Lukasz Kuszel
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | - Ewa Wasilewska
- Department of Radiology, Children's Hospital, New Orleans, USA
| | - Kazimierz Kozlowski
- Department of Medical Imaging, The Children's Hospital at Westmead, Sydney, Australia
| | - Malwina Czarny-Ratajczak
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland; Department of Medicine, Center for Aging, Tulane University, School of Medicine, New Orleans, LA, USA.
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15
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Ghosh A, Kaur N, Kumar A, Goswami C. Why individual thermo sensation and pain perception varies? Clue of disruptive mutations in TRPVs from 2504 human genome data. Channels (Austin) 2016; 10:339-345. [PMID: 26962677 DOI: 10.1080/19336950.2016.1162365] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Every individual varies in character and so do their sensory functions and perceptions. The molecular mechanism and the molecular candidates involved in these processes are assumed to be similar if not same. So far several molecular factors have been identified which are fairly conserved across the phylogenetic tree and are involved in these complex sensory functions. Among all, members belonging to Transient Receptor Potential (TRP) channels have been widely characterized for their involvement in thermo-sensation. These include TRPV1 to TRPV4 channels which reveal complex thermo-gating behavior in response to changes in temperature. The molecular evolution of these channels is highly correlative with the thermal response of different species. However, recent 2504 human genome data suggest that these thermo-sensitive TRPV channels are highly variable and carry possible deleterious mutations in human population. These unexpected findings may explain the individual differences in terms of complex sensory functions.
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Affiliation(s)
- Arijit Ghosh
- a School of Biological Sciences, National Institute of Science Education and Research, Institute of Physics Campus , Bhubaneswar , Orissa , India.,b School of Biological Sciences, National Institute of Science Education and Research, Jatni Campus , Bhubaneswar , Orissa , India
| | - Navneet Kaur
- c School of Biotechnology, KIIT University , Bhubaneswar , Orissa , India
| | - Abhishek Kumar
- d Molecular Genetic Epidemiology, Deutsches Krebsforschungszentrum (DKFZ) , Heidelberg , Germany
| | - Chandan Goswami
- a School of Biological Sciences, National Institute of Science Education and Research, Institute of Physics Campus , Bhubaneswar , Orissa , India.,b School of Biological Sciences, National Institute of Science Education and Research, Jatni Campus , Bhubaneswar , Orissa , India
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16
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Yang C, Zhang X, Guo Y, Meng F, Sachs F, Guo J. Mechanical dynamics in live cells and fluorescence-based force/tension sensors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1889-904. [PMID: 25958335 DOI: 10.1016/j.bbamcr.2015.05.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Revised: 04/07/2015] [Accepted: 05/01/2015] [Indexed: 01/13/2023]
Abstract
Three signaling systems play the fundamental roles in modulating cell activities: chemical, electrical, and mechanical. While the former two are well studied, the mechanical signaling system is still elusive because of the lack of methods to measure structural forces in real time at cellular and subcellular levels. Indeed, almost all biological processes are responsive to modulation by mechanical forces that trigger dispersive downstream electrical and biochemical pathways. Communication among the three systems is essential to make cells and tissues receptive to environmental changes. Cells have evolved many sophisticated mechanisms for the generation, perception and transduction of mechanical forces, including motor proteins and mechanosensors. In this review, we introduce some background information about mechanical dynamics in live cells, including the ubiquitous mechanical activity, various types of mechanical stimuli exerted on cells and the different mechanosensors. We also summarize recent results obtained using genetically encoded FRET (fluorescence resonance energy transfer)-based force/tension sensors; a new technique used to measure mechanical forces in structural proteins. The sensors have been incorporated into many specific structural proteins and have measured the force gradients in real time within live cells, tissues, and animals.
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Affiliation(s)
- Chao Yang
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China
| | - Xiaohan Zhang
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China
| | - Yichen Guo
- The University of Alabama, Tuscaloosa, AL, 35401, USA
| | - Fanjie Meng
- Physiology and Biophysics Department, Center for Single Molecule Studies, University at Buffalo, The State University of New York at Buffalo, Buffalo, NY, 14214, USA
| | - Frederick Sachs
- Physiology and Biophysics Department, Center for Single Molecule Studies, University at Buffalo, The State University of New York at Buffalo, Buffalo, NY, 14214, USA
| | - Jun Guo
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China.
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17
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Drew AP, Zhu D, Kidambi A, Ly C, Tey S, Brewer MH, Ahmad-Annuar A, Nicholson GA, Kennerson ML. Improved inherited peripheral neuropathy genetic diagnosis by whole-exome sequencing. Mol Genet Genomic Med 2015; 3:143-54. [PMID: 25802885 PMCID: PMC4367087 DOI: 10.1002/mgg3.126] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/07/2014] [Accepted: 11/13/2014] [Indexed: 12/31/2022] Open
Abstract
Inherited peripheral neuropathies (IPNs) are a group of related diseases primarily affecting the peripheral motor and sensory neurons. They include the hereditary sensory neuropathies (HSN), hereditary motor neuropathies (HMN), and Charcot-Marie-Tooth disease (CMT). Using whole-exome sequencing (WES) to achieve a genetic diagnosis is particularly suited to IPNs, where over 80 genes are involved with weak genotype–phenotype correlations beyond the most common genes. We performed WES for 110 index patients with IPN where the genetic cause was undetermined after previous screening for mutations in common genes selected by phenotype and mode of inheritance. We identified 41 missense sequence variants in the known IPN genes in our cohort of 110 index patients. Nine variants (8%), identified in the genes MFN2, GJB1, BSCL2, and SETX, are previously reported mutations and considered to be pathogenic in these families. Twelve novel variants (11%) in the genes NEFL, TRPV4, KIF1B, BICD2, and SETX are implicated in the disease but require further evidence of pathogenicity. The remaining 20 variants were confirmed as polymorphisms (not causing the disease) and are detailed here to help interpret sequence variants identified in other family studies. Validation using segregation, normal controls, and bioinformatics tools was valuable as supporting evidence for sequence variants implicated in disease. In addition, we identified one SETX sequence variant (c.7640T>C), previously reported as a putative mutation, which we have confirmed as a nonpathogenic rare polymorphism. This study highlights the advantage of using WES for genetic diagnosis in highly heterogeneous diseases such as IPNs and has been particularly powerful in this cohort where genetic diagnosis could not be achieved due to phenotype and mode of inheritance not being previously obvious. However, first tier testing for common genes in clinically well-defined cases remains important and will account for most positive results.
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Affiliation(s)
- Alexander P Drew
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney, Australia
| | - Danqing Zhu
- Molecular Medicine Laboratory, Concord Hospital Sydney, Australia
| | - Aditi Kidambi
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney, Australia
| | - Carolyn Ly
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney, Australia
| | - Shelisa Tey
- Department of Biomedical Science, Faculty of Medicine, University of Malaya 50603, Kuala Lumpur, Malaysia
| | - Megan H Brewer
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney, Australia ; Sydney Medical School, University of Sydney Sydney, Australia
| | - Azlina Ahmad-Annuar
- Department of Biomedical Science, Faculty of Medicine, University of Malaya 50603, Kuala Lumpur, Malaysia
| | - Garth A Nicholson
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney, Australia ; Molecular Medicine Laboratory, Concord Hospital Sydney, Australia ; Sydney Medical School, University of Sydney Sydney, Australia
| | - Marina L Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute Sydney, Australia ; Molecular Medicine Laboratory, Concord Hospital Sydney, Australia ; Sydney Medical School, University of Sydney Sydney, Australia
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18
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Weinstein MM, Tompson SW, Chen Y, Lee B, Cohn DH. Mice expressing mutant Trpv4 recapitulate the human TRPV4 disorders. J Bone Miner Res 2014; 29:1815-1822. [PMID: 24644033 PMCID: PMC4108531 DOI: 10.1002/jbmr.2220] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 02/21/2014] [Accepted: 03/06/2014] [Indexed: 11/08/2022]
Abstract
Activating mutations in transient receptor potential vanilloid family member 4 (Trpv4) are known to cause a spectrum of skeletal dysplasias ranging from autosomal dominant brachyolmia to lethal metatropic dysplasia. To develop an animal model of these disorders, we created transgenic mice expressing either wild-type or mutant TRPV4. Mice transgenic for wild-type Trpv4 showed no morphological changes at embryonic day 16.5 but did have a delay in bone mineralization. Overexpression of a mutant TRPV4 caused a lethal skeletal dysplasia that phenocopied many abnormalities associated with metatropic dysplasia in humans, including dumbbell-shaped long bones, a small ribcage, abnormalities in the autopod, and abnormal ossification in the vertebrae. The difference in phenotype between embryos transgenic for wild-type or mutant Trpv4 demonstrates that an increased amount of wild-type protein can be tolerated and that an activating mutation of this protein is required to produce a skeletal dysplasia phenotype.
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Affiliation(s)
- Michael M Weinstein
- Department of Molecular, Cell, and Developmental Biology, Orthopaedic Hospital Research Center, University of California, Los Angeles, CA 90095.,Department of Orthopaedic Surgery and Orthopaedic Hospital Research Center, University of California, Los Angeles, CA 90095
| | - Stuart W Tompson
- Department of Molecular, Cell, and Developmental Biology, Orthopaedic Hospital Research Center, University of California, Los Angeles, CA 90095
| | - Yuqing Chen
- Howard Hughes Medical Institute and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
| | - Brendan Lee
- Howard Hughes Medical Institute and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030
| | - Daniel H Cohn
- Department of Molecular, Cell, and Developmental Biology, Orthopaedic Hospital Research Center, University of California, Los Angeles, CA 90095.,Department of Orthopaedic Surgery and Orthopaedic Hospital Research Center, University of California, Los Angeles, CA 90095
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19
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Saitta B, Passarini J, Sareen D, Ornelas L, Sahabian A, Argade S, Krakow D, Cohn DH, Svendsen CN, Rimoin DL. Patient-derived skeletal dysplasia induced pluripotent stem cells display abnormal chondrogenic marker expression and regulation by BMP2 and TGFβ1. Stem Cells Dev 2014; 23:1464-78. [PMID: 24559391 DOI: 10.1089/scd.2014.0014] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Skeletal dysplasias (SDs) are caused by abnormal chondrogenesis during cartilage growth plate differentiation. To study early stages of aberrant cartilage formation in vitro, we generated the first induced pluripotent stem cells (iPSCs) from fibroblasts of an SD patient with a lethal form of metatropic dysplasia, caused by a dominant mutation (I604M) in the calcium channel gene TRPV4. When micromasses were grown in chondrogenic differentiation conditions and compared with control iPSCs, mutant TRPV4-iPSCs showed significantly (P<0.05) decreased expression by quantitative real-time polymerase chain reaction of COL2A1 (IIA and IIB forms), SOX9, Aggrecan, COL10A1, and RUNX2, all of which are cartilage growth plate markers. We found that stimulation with BMP2, but not TGFβ1, up-regulated COL2A1 (IIA and IIB) and SOX9 gene expression, only in control iPSCs. COL2A1 (Collagen II) expression data were confirmed at the protein level by western blot and immunofluorescence microscopy. TRPV4-iPSCs showed only focal areas of Alcian blue stain for proteoglycans, while in control iPSCs the stain was seen throughout the micromass sample. Similar staining patterns were found in neonatal cartilage from control and patient samples. We also found that COL1A1 (Collagen I), a marker of osteogenic differentiation, was significantly (P<0.05) up-regulated at the mRNA level in TRPV4-iPSCs when compared with the control, and confirmed at the protein level. Collagen I expression in the TRPV4 model also may correlate with abnormal staining patterns seen in patient tissues. This study demonstrates that an iPSC model can recapitulate normal chondrogenesis and that mutant TRPV4-iPSCs reflect molecular evidence of aberrant chondrogenic developmental processes, which could be used to design therapeutic approaches for disorders of cartilage.
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Affiliation(s)
- Biagio Saitta
- 1 Department of Biomedical Sciences, Cedars-Sinai Medical Center , Los Angeles, California
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20
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Wood TC, Harvey K, Beck M, Burin MG, Chien YH, Church HJ, D'Almeida V, van Diggelen OP, Fietz M, Giugliani R, Harmatz P, Hawley SM, Hwu WL, Ketteridge D, Lukacs Z, Miller N, Pasquali M, Schenone A, Thompson JN, Tylee K, Yu C, Hendriksz CJ. Diagnosing mucopolysaccharidosis IVA. J Inherit Metab Dis 2013; 36:293-307. [PMID: 23371450 PMCID: PMC3590423 DOI: 10.1007/s10545-013-9587-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 12/05/2012] [Accepted: 01/09/2013] [Indexed: 12/02/2022]
Abstract
Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is an autosomal recessive lysosomal storage disorder resulting from a deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS) activity. Diagnosis can be challenging and requires agreement of clinical, radiographic, and laboratory findings. A group of biochemical genetics laboratory directors and clinicians involved in the diagnosis of MPS IVA, convened by BioMarin Pharmaceutical Inc., met to develop recommendations for diagnosis. The following conclusions were reached. Due to the wide variation and subtleties of radiographic findings, imaging of multiple body regions is recommended. Urinary glycosaminoglycan analysis is particularly problematic for MPS IVA and it is strongly recommended to proceed to enzyme activity testing even if urine appears normal when there is clinical suspicion of MPS IVA. Enzyme activity testing of GALNS is essential in diagnosing MPS IVA. Additional analyses to confirm sample integrity and rule out MPS IVB, multiple sulfatase deficiency, and mucolipidoses types II/III are critical as part of enzyme activity testing. Leukocytes or cultured dermal fibroblasts are strongly recommended for enzyme activity testing to confirm screening results. Molecular testing may also be used to confirm the diagnosis in many patients. However, two known or probable causative mutations may not be identified in all cases of MPS IVA. A diagnostic testing algorithm is presented which attempts to streamline this complex testing process.
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Affiliation(s)
- Timothy C Wood
- Biochemical Genetics Laboratory, Greenwood Genetic Center, 106 Gregor Mendel Circle, Greenwood, SC 29646, USA.
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21
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Nilius B, Voets T. The puzzle of TRPV4 channelopathies. EMBO Rep 2013; 14:152-63. [PMID: 23306656 DOI: 10.1038/embor.2012.219] [Citation(s) in RCA: 218] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 12/10/2012] [Indexed: 11/09/2022] Open
Abstract
Hereditary channelopathies, that is, mutations in channel genes that alter channel function and are causal for the pathogenesis of the disease, have been described for several members of the transient receptor potential channel family. Mutations in the TRPV4 gene, encoding a polymodal Ca(2+) permeable channel, are causative for several human diseases, which affect the skeletal system and the peripheral nervous system, with highly variable phenotypes. In this review, we describe the phenotypes of TRPV4 channelopathies and overlapping symptoms. Putative mechanisms to explain the puzzle, and how mutations in the same region of the channel cause different diseases, are discussed and experimental approaches to tackle this surprising problem are suggested.
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Affiliation(s)
- Bernd Nilius
- KU Leuven, Department of Cellular & Molecular Medicine, Laboratory of Ion Channel Research, Campus Gasthuisberg, Leuven, Belgium.
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22
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Kang SS, Shin SH, Auh CK, Chun J. Human skeletal dysplasia caused by a constitutive activated transient receptor potential vanilloid 4 (TRPV4) cation channel mutation. Exp Mol Med 2012; 44:707-22. [PMID: 23143559 PMCID: PMC3538978 DOI: 10.3858/emm.2012.44.12.080] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2012] [Indexed: 12/23/2022] Open
Abstract
The transient receptor potential vanilloid 4 (TRPV4) cation channel, a member of the TRP vanilloid subfamily, is expressed in a broad range of tissues where it participates in the generation of Ca²⁺ signals and/or depolarization of the membrane potential. Regulation of TRPV4 abundance at the cell surface is critical for osmo- and mechanotransduction. Defects in TRPV4 are the cause of several human diseases, including brachyolmia type 3 (MIM:113500) (also known as brachyrachia or spondylometaphyseal dysplasia Kozlowski type [MIM:118452]), and metatropic dysplasia (MIM:156530) (also called metatropic dwarfism or parastremmatic dwarfism [MIM:168400]). These bone dysplasia mutants are characterized by severe dwarfism, kyphoscoliosis, distortion and bowing of the extremities, and contractures of the large joints. These diseases are characterized by a combination of decreased bone density, bowing of the long bones, platyspondyly, and striking irregularities of endochondral ossification with areas of calcific stippling and streaking in radiolucent epiphyses, metaphyses, and apophyses. In this review, we discuss the potential effect of the mutation on the regulation of TRPV4 functions, which are related to human diseases through deviated function. In particular, we emphasize how the constitutive active TRPV4 mutant affects endochondral ossification with a reduced number of hypertrophic chondrocytes and the presence of cartilage islands within the zone of primary mineralization. In addition, we summarize current knowledge about the role of TRPV4 in the pathogenesis of several diseases.
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Affiliation(s)
- Sang Sun Kang
- Department of Biology Education Chungbuk National University Cheongju 361-763, Korea.
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23
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Inada H, Procko E, Sotomayor M, Gaudet R. Structural and biochemical consequences of disease-causing mutations in the ankyrin repeat domain of the human TRPV4 channel. Biochemistry 2012; 51:6195-206. [PMID: 22702953 PMCID: PMC3413242 DOI: 10.1021/bi300279b] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
The TRPV4 calcium-permeable cation channel plays important
physiological
roles in osmosensation, mechanosensation, cell barrier formation,
and bone homeostasis. Recent studies reported that mutations in TRPV4,
including some in its ankyrin repeat domain (ARD), are associated
with human inherited diseases, including neuropathies and skeletal
dysplasias, probably because of the increased constitutive activity
of the channel. TRPV4 activity is regulated by the binding of calmodulin
and small molecules such as ATP to the ARD at its cytoplasmic N-terminus.
We determined structures of ATP-free and -bound forms of human TRPV4-ARD
and compared them with available TRPV-ARD structures. The third inter-repeat
loop region (Finger 3 loop) is flexible and may act as a switch to
regulate channel activity. Comparisons of TRPV-ARD structures also
suggest an evolutionary link between ARD structure and ATP binding
ability. Thermal stability analyses and molecular dynamics simulations
suggest that ATP increases stability in TRPV-ARDs that can bind ATP.
Biochemical analyses of a large panel of TRPV4-ARD mutations associated
with human inherited diseases showed that some impaired thermal stability
while others weakened ATP binding ability, suggesting molecular mechanisms
for the diseases.
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Affiliation(s)
- Hitoshi Inada
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
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24
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Nemec SF, Cohn DH, Krakow D, Funari VA, Rimoin DL, Lachman RS. The importance of conventional radiography in the mutational analysis of skeletal dysplasias (the TRPV4 mutational family). Pediatr Radiol 2012; 42:15-23. [PMID: 21863289 DOI: 10.1007/s00247-011-2229-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2011] [Revised: 07/12/2011] [Accepted: 07/26/2011] [Indexed: 12/25/2022]
Abstract
The spondylo and spondylometaphyseal dysplasias (SMDs) are characterized by vertebral changes and metaphyseal abnormalities of the tubular bones, which produce a phenotypic spectrum of disorders from the mild autosomal-dominant brachyolmia to SMD Kozlowski to autosomal-dominant metatropic dysplasia. Investigations have recently drawn on the similar radiographic features of those conditions to define a new family of skeletal dysplasias caused by mutations in the transient receptor potential cation channel vanilloid 4 (TRPV4). This review demonstrates the significance of radiography in the discovery of a new bone dysplasia family due to mutations in a single gene.
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Affiliation(s)
- Stefan F Nemec
- International Skeletal Dysplasia Registry, Medical Genetics Institute, Cedars Sinai Medical Center, 8700 Beverly Boulevard, PACT Suite 400, Los Angeles, CA 90048, USA.
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Andreucci E, Aftimos S, Alcausin M, Haan E, Hunter W, Kannu P, Kerr B, McGillivray G, McKinlay Gardner RJ, Patricelli MG, Sillence D, Thompson E, Zacharin M, Zankl A, Lamandé SR, Savarirayan R. TRPV4 related skeletal dysplasias: a phenotypic spectrum highlighted byclinical, radiographic, and molecular studies in 21 new families. Orphanet J Rare Dis 2011; 6:37. [PMID: 21658220 PMCID: PMC3135501 DOI: 10.1186/1750-1172-6-37] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 06/09/2011] [Indexed: 08/30/2023] Open
Abstract
Background The TRPV4 gene encodes a calcium-permeable ion-channel that is widely expressed, responds to many different stimuli and participates in an extraordinarily wide range of physiologic processes. Autosomal dominant brachyolmia, spondylometaphyseal dysplasia Kozlowski type (SMDK) and metatropic dysplasia (MD) are currently considered three distinct skeletal dysplasias with some shared clinical features, including short stature, platyspondyly, and progressive scoliosis. Recently, TRPV4 mutations have been found in patients diagnosed with these skeletal phenotypes. Methods and Results We critically analysed the clinical and radiographic data on 26 subjects from 21 families, all of whom had a clinical diagnosis of one of the conditions described above: 15 with MD; 9 with SMDK; and 2 with brachyolmia. We sequenced TRPV4 and identified 9 different mutations in 22 patients, 4 previously described, and 5 novel. There were 4 mutation-negative cases: one with MD and one with SMDK, both displaying atypical clinical and radiographic features for these diagnoses; and two with brachyolmia, who had isolated spine changes and no metaphyseal involvement. Conclusions Our data suggest the TRPV4 skeletal dysplasias represent a continuum of severity with areas of phenotypic overlap, even within the same family. We propose that AD brachyolmia lies at the mildest end of this spectrum and, since all cases described with this diagnosis and TRPV4 mutations display metaphyseal changes, we suggest that it is not a distinct entity but represents the mildest phenotypic expression of SMDK.
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Affiliation(s)
- Elena Andreucci
- Genetic Health Services Victoria and Murdoch Childrens Research Institute, Parkville, Victoria, Australia.
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26
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Loukin S, Su Z, Kung C. Increased basal activity is a key determinant in the severity of human skeletal dysplasia caused by TRPV4 mutations. PLoS One 2011; 6:e19533. [PMID: 21573172 PMCID: PMC3088684 DOI: 10.1371/journal.pone.0019533] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Accepted: 04/04/2011] [Indexed: 02/01/2023] Open
Abstract
TRPV4 is a mechanically activated Ca2+-passing channel implicated in the sensing of forces, including those acting on bones. To date, 33 mutations are known to affect human bone development to different extents. The spectrum of these skeletal dysplasias (SD) ranges from dominantly inherited mild brachylomia (BO) to neonatal lethal forms of metatropic dysplasia (MD). Complexities of the results from fluorescence and electrophysiological studies have led to questions on whether channel activity is a good predictor of disease severity. Here we report on a systematic examination of 14 TRPV4 mutant alleles covering the entire SD spectrum. Expressed in Xenopus oocyte and without any stimulation, the wild-type channel had a ∼1% open probability (Po) while those of most of the lethal MD channels approached 100%. All mutant channels had higher basal open probabilities, which limited their further increase by agonist or hypotonicity. The magnitude of this limitation revealed a clear correlation between the degree of over-activity (the molecular phenotype) and the severity of the disease over the entire spectrum (the biological phenotype). Thus, while other factors are at play, our results are consistent with the increased TRPV4 basal activity being a critical determinant of the severity of skeletal dysplasia. We discuss how the channel over-activity may lead to the “gain-of-function” phenotype and speculate that the function of wild-type TRPV4 may be secondary in normal bone development but crucial in an acute process such as fracture repair in the adult.
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Affiliation(s)
- Stephen Loukin
- Laboratory of Molecular Biology, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- * E-mail:
| | - Zhenwei Su
- Laboratory of Molecular Biology, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Ching Kung
- Laboratory of Molecular Biology, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- Department of Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
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27
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Holzer P. Transient receptor potential (TRP) channels as drug targets for diseases of the digestive system. Pharmacol Ther 2011; 131:142-70. [PMID: 21420431 PMCID: PMC3107431 DOI: 10.1016/j.pharmthera.2011.03.006] [Citation(s) in RCA: 172] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 03/01/2011] [Indexed: 12/12/2022]
Abstract
Approximately 20 of the 30 mammalian transient receptor potential (TRP) channel subunits are expressed by specific neurons and cells within the alimentary canal. They subserve important roles in taste, chemesthesis, mechanosensation, pain and hyperalgesia and contribute to the regulation of gastrointestinal motility, absorptive and secretory processes, blood flow, and mucosal homeostasis. In a cellular perspective, TRP channels operate either as primary detectors of chemical and physical stimuli, as secondary transducers of ionotropic or metabotropic receptors, or as ion transport channels. The polymodal sensory function of TRPA1, TRPM5, TRPM8, TRPP2, TRPV1, TRPV3 and TRPV4 enables the digestive system to survey its physical and chemical environment, which is relevant to all processes of digestion. TRPV5 and TRPV6 as well as TRPM6 and TRPM7 contribute to the absorption of Ca²⁺ and Mg²⁺, respectively. TRPM7 participates in intestinal pacemaker activity, and TRPC4 transduces muscarinic acetylcholine receptor activation to smooth muscle contraction. Changes in TRP channel expression or function are associated with a variety of diseases/disorders of the digestive system, notably gastro-esophageal reflux disease, inflammatory bowel disease, pain and hyperalgesia in heartburn, functional dyspepsia and irritable bowel syndrome, cholera, hypomagnesemia with secondary hypocalcemia, infantile hypertrophic pyloric stenosis, esophageal, gastrointestinal and pancreatic cancer, and polycystic liver disease. These implications identify TRP channels as promising drug targets for the management of a number of gastrointestinal pathologies. As a result, major efforts are put into the development of selective TRP channel agonists and antagonists and the assessment of their therapeutic potential.
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Affiliation(s)
- Peter Holzer
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Universitätsplatz 4, A-8010 Graz, Austria.
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28
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Klein CJ, Shi Y, Fecto F, Donaghy M, Nicholson G, McEntagart ME, Crosby AH, Wu Y, Lou H, McEvoy KM, Siddique T, Deng HX, Dyck PJ. TRPV4 mutations and cytotoxic hypercalcemia in axonal Charcot-Marie-Tooth neuropathies. Neurology 2011; 76:887-94. [PMID: 21288981 DOI: 10.1212/wnl.0b013e31820f2de3] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To improve understanding of TRPV4-associated axonal Charcot-Marie-Tooth (CMT) neuropathy phenotypes and their debated pathologic mechanism. METHODS A total of 17 CMT2C phenotypic families with vocal cord and diaphragmatic involvement and 36 clinically undifferentiated CMT2 subjects underwent sequencing analysis of the coding region of TRPV4. Functional studies of mutant proteins were performed using transiently transfected cells for TRPV4 subcellular localization, basal and stimulated Ca(2+) channel analysis, and cell viability assay with or without channel blockade. RESULTS Two TRPV4 mutations R232C and R316H from 17 CMT2C families were identified in the ankyrin repeat domains. The R316H is a novel de novo mutation found in a patient with CMT2C phenotype. The family with R232C mutation had individuals with and without vocal cord and diaphragm involvement. Both mutant TRPV4 proteins had normal subcellular localization in HEK293 and HeLa cells. Cells transfected with R232C and R316H displayed increased intracellular Ca(2+) levels and reversible cell death by the TRPV channel antagonist, ruthenium red. CONCLUSION TRPV4 ankyrin domain alterations including a novel de novo mutation cause axonal CMT2. Individuals with the same mutation may have nondistinct CMT2 or have phenotypic CMT2C with vocal cord paresis. Reversible hypercalcemic gain-of-function of mutant TRPV4 instead of loss-of-function appears to be pathologically important. The reversibility of cell death by channel blockade provides an attractive area of investigation in consideration of treatable axonal degeneration.
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Affiliation(s)
- C J Klein
- Department of Neurology and Division of Peripheral Nerve Diseases, Mayo Clinic Foundation, Rochester, MN 55905, USA.
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29
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Chen DH, Sul Y, Weiss M, Hillel A, Lipe H, Wolff J, Matsushita M, Raskind W, Bird T. CMT2C with vocal cord paresis associated with short stature and mutations in the TRPV4 gene. Neurology 2010; 75:1968-75. [PMID: 21115951 DOI: 10.1212/wnl.0b013e3181ffe4bb] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Recently, mutations in the transient receptor potential cation channel, subfamily V, member 4 gene (TRPV4) have been reported in Charcot-Marie-Tooth Type 2C (CMT2C) with vocal cord paresis. Other mutations in this same gene have been described in separate families with various skeletal dysplasias. Further clarification is needed of the different phenotypes associated with this gene. METHODS We performed clinical evaluation, electrophysiology, and genetic analysis of the TRPV4 gene in 2 families with CMT2C. RESULTS Two multigenerational families had a motor greater than sensory axonal neuropathy associated with variable vocal cord paresis. The vocal cord paresis varied from absent to severe, requiring permanent tracheotomy in 2 subjects. One family with mild neuropathy also manifested pronounced short stature, more than 2 SD below the average height for white Americans. There was one instance of dolichocephaly. A novel S542Y mutation in the TRPV4 gene was identified in this family. The other family had a more severe, progressive, motor neuropathy with sensory loss, but less remarkable short stature and an R315W mutation in TRPV4. Third cranial nerve involvement and sleep apnea occurred in one subject in each family. CONCLUSION CMT2C with axonal neuropathy, vocal cord paresis, and short stature is a unique syndrome associated with mutations in the TRPV4 gene. Mutations in TRPV4 can cause abnormalities in bone, peripheral nerve, or both and may result in highly variable orthopedic and neurologic phenotypes.
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Affiliation(s)
- D-H Chen
- Department of Neurology, University of Washington Medical School, Seattle, WA, USA
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