1
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Wang Y, Xu L, Zhang Y, Fu H, Gao L, Guan Y, Gu W, Sun J, Chen X, Yang F, Lai E, Wang J, Jin Y, Kou Z, Qiu X, Mao J, Hu L. Dent disease 1-linked novel CLCN5 mutations result in aberrant location and reduced ion currents. Int J Biol Macromol 2024; 257:128564. [PMID: 38061527 DOI: 10.1016/j.ijbiomac.2023.128564] [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: 06/13/2023] [Revised: 11/12/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023]
Abstract
Dent disease is a rare renal tubular disease with X-linked recessive inheritance characterized by low molecular weight proteinuria (LMWP), hypercalciuria, and nephrocalcinosis. Mutations disrupting the 2Cl-/1H+ exchange activity of chloride voltage-gated channel 5 (CLCN5) have been causally linked to the most common form, Dent disease 1 (DD1), although the pathophysiological mechanisms remain unclear. Here, we conducted the whole exome capture sequencing and bioinformatics analysis within our DD1 cohort to identify two novel causal mutations in CLCN5 (c.749 G > A, p. G250D, c.829 A > C, p. T277P). Molecular dynamics simulations of ClC-5 homology model suggested that these mutations potentially may induce structural changes, destabilizing ClC-5. Overexpression of variants in vitro revealed aberrant subcellular localization in the endoplasmic reticulum (ER), significant accumulation of insoluble aggregates, and disrupted ion transport function in voltage clamp recordings. Moreover, human kidney-2 (HK-2) cells overexpressing either G250D or T277P displayed higher cell-substrate adhesion, migration capability but reduced endocytic function, as well as substantially altered transcriptomic profiles with G250D resulting in stronger deleterious effects. These cumulative findings supported pathogenic role of these ClC-5 mutations in DD1 and suggested a cellular mechanism for disrupted renal function in Dent disease patients, as well as a potential target for diagnostic biomarker or therapeutic strategy development.
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Affiliation(s)
- Yan Wang
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Lizhen Xu
- Department of Biophysics, and Kidney Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Ying Zhang
- Eye Center of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Haidong Fu
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Langping Gao
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yuelin Guan
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Weizhong Gu
- Department of Pathology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Jingmiao Sun
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Xiangjun Chen
- Eye Center of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China; Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou 310020, China
| | - Fan Yang
- Department of Biophysics, and Kidney Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - EnYin Lai
- Department of Physiology School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China
| | - Jingjing Wang
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yanyan Jin
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Ziqi Kou
- Institute for Brain Research and Rehabilitation, and Guangdong Key Laboratory of Mental Health and Cognitive Science, South China Normal University, Guangzhou 510631, China
| | - Xingyu Qiu
- Department of Physiology School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China
| | - Jianhua Mao
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
| | - Lidan Hu
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
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2
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Development of ultra-deep targeted RNA sequencing for analyzing X-chromosome inactivation in female Dent disease. J Hum Genet 2018; 63:589-595. [DOI: 10.1038/s10038-018-0415-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/09/2018] [Accepted: 01/17/2018] [Indexed: 11/08/2022]
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3
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Yamamura T, Nozu K, Miyoshi Y, Nakanishi K, Fujimura J, Horinouchi T, Minamikawa S, Mori N, Fujimaru R, Nakanishi K, Ninchoji T, Kaito H, Mariko TI, Morioka I, Matsuo M, Iijima K. An in vitro splicing assay reveals the pathogenicity of a novel intronic variant in ATP6V0A4 for autosomal recessive distal renal tubular acidosis. BMC Nephrol 2017; 18:353. [PMID: 29202719 PMCID: PMC5716019 DOI: 10.1186/s12882-017-0774-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 11/23/2017] [Indexed: 02/07/2023] Open
Abstract
Background Autosomal recessive distal renal tubular acidosis (dRTA) is a rare hereditary disease caused by pathogenic variants in the ATP6V0A4 gene or ATP6V1B1 gene, and characterized by hyperchloremic metabolic acidosis with normal anion gap, hypokalemia, hypercalciuria, hypocitraturia and nephrocalcinosis. Although several intronic nucleotide variants in these genes have been detected, all of them fell in the apparent splice consensus sequence. In general, transcriptional analysis is necessary to determine the effect on function of the novel intronic variants located out of splicing consensus sequences. In recent years, functional splicing analysis using minigene construction was used to assess the pathogenicity of novel intoronic variant in various field. Methods We investigated a sporadic case of dRTA with a compound heterozygous mutation in the ATP6V0A4 gene, revealed by next generation sequencing. One variant was already reported as pathogenic; however, the other was a novel variant in intron 11 (c.1029 + 5G > A) falling outside of the apparent splicing consensus sequence. Expression of ATP6V0A4 was not detected in peripheral leukocytes by RT-PCR analysis. Therefore, an in vitro functional splicing study using minigene construction was conducted to analyze the splicing pattern of the novel variant. Results A minigene assay revealed that the novel intronic variant leads to a 104 bp insertion immediately following exon 11. In addition, this result was confirmed using RNA extracted from the patient’s cultured leukocytes. Conclusion These results proved the pathogenicity of a novel intronic variant in our patient. We concluded that the minigene assay is a useful, non-invasive method for functional splicing analysis of inherited kidney disease, even if standard transcriptional analysis could not detect abnormal mRNA. Electronic supplementary material The online version of this article (10.1186/s12882-017-0774-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan.
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Yuya Miyoshi
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Keita Nakanishi
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Junya Fujimura
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Tomoko Horinouchi
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Shogo Minamikawa
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Nobuo Mori
- Nakano Children's Hospital, 4-13-17 Shinmori, Asahi, Osaka, 5350022, Japan
| | - Rika Fujimaru
- Department of Pediatrics, Osaka City General Hospital, 2-13-22 Miyakojimahondori, Miyakojima, Osaka, 5340021, Japan
| | - Koichi Nakanishi
- Department of Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Nakagami, 9030125, Japan
| | - Takeshi Ninchoji
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Hiroshi Kaito
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Taniguchi-Ikeda Mariko
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Ichiro Morioka
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
| | - Masafumi Matsuo
- Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani, Nishi, Kobe, 6512180, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunokicho, Chuo, Kobe, Hyogo, 6500017, Japan
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4
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van Berkel Y, Ludwig M, van Wijk JAE, Bökenkamp A. Proteinuria in Dent disease: a review of the literature. Pediatr Nephrol 2017; 32:1851-1859. [PMID: 27757584 PMCID: PMC5579149 DOI: 10.1007/s00467-016-3499-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/23/2016] [Accepted: 08/25/2016] [Indexed: 12/18/2022]
Abstract
BACKGROUND Dent disease is a rare X-linked recessive proximal tubulopathy caused by mutations in CLCN5 (Dent-1) or OCRL (Dent-2). As a rule, total protein excretion (TPE) is low in tubular proteinuria compared with glomerular disease. Several authors have reported nephrotic-range proteinuria (NP) and glomerulosclerosis in Dent disease. Therefore, we aimed to analyze protein excretion in patients with documented CLCN5 or OCRL mutations in a systematic literature review. DESIGN PubMed and Embase were searched for cases with documented CLCN5 or OCRL mutations and (semi-)quantitative data on protein excretion. The most reliable data (i.e., TPE > protein-creatinine ratio > Albustix) was used for NP classification. RESULTS Data were available on 148 patients from 47 reports: 126 had a CLCN5 and 22 an OCRLmutation. TPE was not significantly different between both forms (p = 0.11). Fifty-five of 126 (43.7 %) Dent-1 vs 13/22 (59.1 %) Dent-2 patients met the definition of NP (p = 0.25). Serum albumin was normal in all reported cases (24/148). Glomerulosclerosis was noted in 20/32 kidney biopsies and was strongly related to tubulointerstitial fibrosis, but not to kidney function or proteinuria. CONCLUSION More than half of the patients with both forms of Dent disease have NP, and the presence of low molecular weight proteinuria in a patient with NP in the absence of edema and hypoalbuminemia should prompt genetic testing. Even with normal renal function, glomerulosclerosis and tubulointerstitial fibrosis are present in Dent disease. The role of proteinuria in the course of the disease needs to be examined further in longitudinal studies.
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Affiliation(s)
- Youri van Berkel
- Department of Pediatric Nephrology, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
| | - Michael Ludwig
- Department of Clinical Chemistry and Clinical Pharmacology, University of Bonn, Bonn, Germany
| | - Joanna A E van Wijk
- Department of Pediatric Nephrology, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands
| | - Arend Bökenkamp
- Department of Pediatric Nephrology, VU University Medical Center, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands.
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5
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Wong W, Poke G, Stack M, Kara T, Prestidge C, Flintoff K. Phenotypic variability of Dent disease in a large New Zealand kindred. Pediatr Nephrol 2017; 32:365-369. [PMID: 27699523 DOI: 10.1007/s00467-016-3472-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 07/07/2016] [Accepted: 07/07/2016] [Indexed: 01/27/2023]
Abstract
BACKGROUND Dent disease 1 is a rare cause of chronic kidney disease (CKD) in childhood secondary to mutations in the gene encoding the chloride-proton exchanger, CLC-5, which is found mainly in the proximal tubule. Clinical manifestations are variable and there are no known genotype-phenotype correlations. CASE DIAGNOSIS/TREATMENT The proband was identified as having a mutation in CLCN5. The extended family of the proband was invited to participate in a study of Dent disease after several males were noted to have a history of CKD. Urine retinol binding protein, urine calcium, serum creatinine, and DNA samples were collected for analysis. Ten hemizygous males and 6 heterozygous females were identified. Advanced CKD was detected in 3 males (1 child). Renal biopsies in 4 children showed both glomerular and tubulo-interstitial changes. There was no correlation between age and disease severity. CONCLUSIONS This is the first reported family from the southern hemisphere with this condition. A novel CLCN5 mutation is described, c.1618G>C (p.Ala540Pro). The severity of renal disease varies greatly among individuals.
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Affiliation(s)
- William Wong
- Department of Paediatric Nephrology, Starship Children's Hospital, Private Bag 92024, Park Road, Auckland, New Zealand.
| | - Gemma Poke
- Genetic Health Service New Zealand Central Hub, Wellington, New Zealand
| | - Maria Stack
- Department of Paediatric Nephrology, Starship Children's Hospital, Private Bag 92024, Park Road, Auckland, New Zealand
| | - Tonya Kara
- Department of Paediatric Nephrology, Starship Children's Hospital, Private Bag 92024, Park Road, Auckland, New Zealand
| | - Chanel Prestidge
- Department of Paediatric Nephrology, Starship Children's Hospital, Private Bag 92024, Park Road, Auckland, New Zealand
| | - Kim Flintoff
- Wellington Regional Genetics Laboratory, Wellington, New Zealand
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6
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Kubo K, Aizawa T, Watanabe S, Tsugawa K, Tsuruga K, Ito E, Joh K, Tanaka H. Does Dent disease remain an underrecognized cause for young boys with focal glomerulosclerosis? Pediatr Int 2016; 58:747-9. [PMID: 27324082 DOI: 10.1111/ped.12944] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/19/2015] [Accepted: 01/26/2016] [Indexed: 12/11/2022]
Abstract
Focal glomerulosclerosis (FGS) is a histologic entity that causes significant proteinuria in children. Although its etiology varies, recent reports indicated that some young male patients with FGS had underlying Dent disease. We describe the case of a 14-year-old Japanese boy who presented with persistent non-nephrotic range proteinuria, hematuria, and renal insufficiency. The patient was initially diagnosed as having FGS associated with scattered tubulointerstitial fibrosis. Although he had neither nephrocalcinosis nor family history of renal disease including urolithiasis, increased excretion of urinary β2 microglobulin was noted. Genetic analysis for Dent disease indicated a mutation (c.726 + 1G > A) in Chloride Channel, Voltage-Sensitive 5 (CLCN5). Given a recent hypothesis that Dent disease may be underrecognized in children with FGS, a careful diagnostic evaluation for possible underlying Dent disease should be considered in young boys who present with persistent albuminuria associated with high-grade low-molecular-weight proteinuria.
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Affiliation(s)
- Kaori Kubo
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan
| | - Tomomi Aizawa
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan
| | - Shojiro Watanabe
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan
| | - Koji Tsugawa
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan
| | - Kazushi Tsuruga
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan
| | - Etsuro Ito
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan
| | - Kensuke Joh
- Department of School Health Science, Faculty of Education, Hirosaki University, Hirosaki, Japan
| | - Hiroshi Tanaka
- Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan.,Department of Pathology, Tohoku University Graduate School of Medicine, Hirosaki, Japan
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7
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Alexander RT, Cordat E, Chambrey R, Dimke H, Eladari D. Acidosis and Urinary Calcium Excretion: Insights from Genetic Disorders. J Am Soc Nephrol 2016; 27:3511-3520. [PMID: 27468975 DOI: 10.1681/asn.2016030305] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Metabolic acidosis is associated with increased urinary calcium excretion and related sequelae, including nephrocalcinosis and nephrolithiasis. The increased urinary calcium excretion induced by metabolic acidosis predominantly results from increased mobilization of calcium out of bone and inhibition of calcium transport processes within the renal tubule. The mechanisms whereby acid alters the integrity and stability of bone have been examined extensively in the published literature. Here, after briefly reviewing this literature, we consider the effects of acid on calcium transport in the renal tubule and then discuss why not all gene defects that cause renal tubular acidosis are associated with hypercalciuria and nephrocalcinosis.
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Affiliation(s)
- R Todd Alexander
- Departments of Pediatrics and .,Physiology, University of Alberta, Edmonton, Canada
| | | | - Régine Chambrey
- Institut National de la Santé et de la Recherche Médicale U970, Paris Centre de Recherche Cardiovasculaire, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Henrik Dimke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Demark; and
| | - Dominique Eladari
- Institut National de la Santé et de la Recherche Médicale U970, Paris Centre de Recherche Cardiovasculaire, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Department of Physiologie, Hôpital Européen Georges Pompidou, Assistance Publique Hôpitaux de Paris, Paris, France
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8
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Mansour-Hendili L, Blanchard A, Le Pottier N, Roncelin I, Lourdel S, Treard C, González W, Vergara-Jaque A, Morin G, Colin E, Holder-Espinasse M, Bacchetta J, Baudouin V, Benoit S, Bérard E, Bourdat-Michel G, Bouchireb K, Burtey S, Cailliez M, Cardon G, Cartery C, Champion G, Chauveau D, Cochat P, Dahan K, De la Faille R, Debray FG, Dehoux L, Deschenes G, Desport E, Devuyst O, Dieguez S, Emma F, Fischbach M, Fouque D, Fourcade J, François H, Gilbert-Dussardier B, Hannedouche T, Houillier P, Izzedine H, Janner M, Karras A, Knebelmann B, Lavocat MP, Lemoine S, Leroy V, Loirat C, Macher MA, Martin-Coignard D, Morin D, Niaudet P, Nivet H, Nobili F, Novo R, Faivre L, Rigothier C, Roussey-Kesler G, Salomon R, Schleich A, Sellier-Leclerc AL, Soulami K, Tiple A, Ulinski T, Vanhille P, Van Regemorter N, Jeunemaître X, Vargas-Poussou R. Mutation Update of the CLCN5 Gene Responsible for Dent Disease 1. Hum Mutat 2015; 36:743-52. [PMID: 25907713 DOI: 10.1002/humu.22804] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/08/2015] [Indexed: 02/06/2023]
Abstract
Dent disease is a rare X-linked tubulopathy characterized by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis and/or nephrolithiasis, progressive renal failure, and variable manifestations of other proximal tubule dysfunctions. It often progresses over a few decades to chronic renal insufficiency, and therefore molecular characterization is important to allow appropriate genetic counseling. Two genetic subtypes have been described to date: Dent disease 1 is caused by mutations of the CLCN5 gene, coding for the chloride/proton exchanger ClC-5; and Dent disease 2 by mutations of the OCRL gene, coding for the inositol polyphosphate 5-phosphatase OCRL-1. Herein, we review previously reported mutations (n = 192) and their associated phenotype in 377 male patients with Dent disease 1 and describe phenotype and novel (n = 42) and recurrent mutations (n = 24) in a large cohort of 117 Dent disease 1 patients belonging to 90 families. The novel missense and in-frame mutations described were mapped onto a three-dimensional homology model of the ClC-5 protein. This analysis suggests that these mutations affect the dimerization process, helix stability, or transport. The phenotype of our cohort patients supports and extends the phenotype that has been reported in smaller studies.
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Affiliation(s)
- Lamisse Mansour-Hendili
- Faculté de Médecine, Université Paris Descartes, Paris, France.,Assistance Publique-Hôpitaux de Paris, Service de Génétique, Hôpital Européen Georges Pompidou, Paris, France
| | - Anne Blanchard
- Faculté de Médecine, Université Paris Descartes, Paris, France.,INSERM, UMR970, Paris-Cardiovascular Research Center, Paris, France.,Assistance Publique-Hôpitaux de Paris, Centre d'investigation clinique, Hôpital Européen Georges Pompidou, Paris, France.,Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France
| | - Nelly Le Pottier
- Assistance Publique-Hôpitaux de Paris, Service de Génétique, Hôpital Européen Georges Pompidou, Paris, France
| | - Isabelle Roncelin
- Assistance Publique-Hôpitaux de Paris, Service de Génétique, Hôpital Européen Georges Pompidou, Paris, France
| | - Stéphane Lourdel
- Sorbonne Universités, UPMC Université, Paris, France.,INSERM, Université Paris Descartes, Sorbonne Paris Cité, UMR S1138, Centre de Recherche des Cordeliers, CNRS ERL 8228, Paris, F-75006, France
| | - Cyrielle Treard
- Assistance Publique-Hôpitaux de Paris, Service de Génétique, Hôpital Européen Georges Pompidou, Paris, France.,INSERM, UMR970, Paris-Cardiovascular Research Center, Paris, France
| | - Wendy González
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca, Talca, Chile
| | - Ariela Vergara-Jaque
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca, Talca, Chile
| | - Gilles Morin
- Service de Génétique et Oncogénétique, Centre Hospitalier Universitaire Amiens Picardie, Amiens, France
| | - Estelle Colin
- Département de Biochimie et Génétique, LUNAM Angers, Centre Hospitalier Universitaire d'Angers, Angers, France
| | - Muriel Holder-Espinasse
- Département de Génétique, Centre Hospitalier Universitaire de Lille, Lille, France.,Department of Clinical Genetics, Guy's Hospital, London, United Kingdom
| | - Justine Bacchetta
- Centre de Référence des Maladies Rénales Rares. Service de Néphrologie Rhumatologie Dermatologie Pédiatriques, Hospices Civils de Lyon, Lyon, France
| | - Véronique Baudouin
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Service de Néphrologie, Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, Paris, France
| | - Stéphane Benoit
- Service de Néphrologie, Centre Hospitalier Universitaire de Tours, Tours, France
| | - Etienne Bérard
- Service de Néphrologie pédiatrique, Centre Hospitalier Universitaire de Nice, Nice, France
| | | | - Karim Bouchireb
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Assistance Publique Hôpitaux de Paris, Hôpital Necker-Enfants-malades, Service de Néphrologie Pédiatrique, Paris, France
| | - Stéphane Burtey
- VRCM, centre de néphrologie et transplantation rénale, Aix-Marseille Université, Marseille, France
| | - Mathilde Cailliez
- Assistance Publique Hôpitaux de Marseille, Unité de Néphrologie Pédiatrique, Hôpital La Timone, Marseille, France
| | - Gérard Cardon
- Service de Néphrologie, Centre Hospitalier de Douai, Douai, France
| | - Claire Cartery
- Assistance Publique-Hôpitaux de Paris, Service de Néphrologie et dialyse, Hôpital Tenon, Paris, France
| | - Gerard Champion
- Département de Pédiatrie, LUNAM Angers, Centre Hospitalier Universitaire d'Angers, Angers, France
| | - Dominique Chauveau
- Centre Hospitalier Universitaire de Toulouse, Département de Néphrologie et Transplantation d'organes, Hôpital Rangueil, Toulouse, France
| | - Pierre Cochat
- Centre de Référence des Maladies Rénales Rares. Service de Néphrologie Rhumatologie Dermatologie Pédiatriques, Hospices Civils de Lyon, Lyon, France
| | - Karin Dahan
- Département de Génétique Humaine, Institut de Pathologie et de Génétique, Gosselies, Belgium
| | - Renaud De la Faille
- Service de Néphrologie Transplantation Dialyse, Centre Hospitalier Universitaire de Bordeaux, Bordeaux, France
| | | | - Laurenne Dehoux
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Service de Néphrologie, Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, Paris, France
| | - Georges Deschenes
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Service de Néphrologie, Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, Paris, France
| | - Estelle Desport
- Service de Néphrologie, Centre Hospitalier Universitaire de Poitiers, Poitiers, France
| | - Olivier Devuyst
- Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.,Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Stella Dieguez
- Nefrologia Infantil, Hospital General de Agudos Dr. Teodoro Álvarez, Buenos Aires, Argentina
| | - Francesco Emma
- Division of Nephrology and Dialysis, Bambino Gesù Children's Hospital - IRCCS, Rome, Italy
| | - Michel Fischbach
- Service de Pédiatrie, Centre Hospitalier Universitaire Hautepierre, Strasbourg, France
| | - Denis Fouque
- Departement de Néphrology, Centre Hospitalier Universitaire Lyon Sud, Lyon, France
| | - Jacques Fourcade
- Service de Néphrology, Centre Hospitalier de Chambery, Chambery, France
| | - Hélène François
- Assistance Publique-Hôpitaux de Paris, Hôpital Kremlin Bicêtre, Service de Néphrologie, Le Kremlin-Bicêtre, France
| | - Brigitte Gilbert-Dussardier
- Centre Hospitalier Universitaire de Poitiers, Service de Génétique, EA 3808, Université de Poitiers, Poitiers, France
| | - Thierry Hannedouche
- Hôpitaux Universitaires de Strasbourg, Service de Néphrologie et Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Pascal Houillier
- Faculté de Médecine, Université Paris Descartes, Paris, France.,Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,INSERM, Université Paris Descartes, Sorbonne Paris Cité, UMR S1138, Centre de Recherche des Cordeliers, CNRS ERL 8228, Paris, F-75006, France.,Assistance Publique Hôpitaux de Paris, Département de Physiologie, Hôpital Européen Georges Pompidou, Paris, France
| | - Hassan Izzedine
- Assistance Publique-Hôpitaux de Paris, Hôpital Pitié Salpêtrière, Service de Néphrologie, Paris, France
| | - Marco Janner
- Department of Paediatric Endocrinology, Diabetology and Metabolism, University of Berne Children's Hospital, Berne, Switzerland
| | - Alexandre Karras
- Assistance Publique Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Néphrologie, Paris, France
| | - Bertrand Knebelmann
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Assistance Publique Hôpitaux de Paris, Hôpital Necker-Enfants-malades, Service de Néphrologie adulte, Paris, France
| | - Marie-Pierre Lavocat
- Département de Pédiatrie, Centre Hospitalier Universitaire de Saint Etienne, Hôpital Nord, Saint Etienne, France
| | - Sandrine Lemoine
- Hospices Civils de Lyon, Service d'Exploration Fonctionnelle Rénale, Hôpital Edouard-Herriot, Lyon, France
| | - Valérie Leroy
- Hôpital Jeanne de Flandre, Service de Néphrologie Pédiatrique, Centre Hospitalier Universitaire de Lille, Lille, France
| | - Chantal Loirat
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Service de Néphrologie, Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, Paris, France
| | - Marie-Alice Macher
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Service de Néphrologie, Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, Paris, France
| | | | - Denis Morin
- Unité de Néphrologie Pédiatrique, Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | - Patrick Niaudet
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Assistance Publique Hôpitaux de Paris, Hôpital Necker-Enfants-malades, Service de Néphrologie Pédiatrique, Paris, France
| | - Hubert Nivet
- Service de Néphrologie, Centre Hospitalier Universitaire de Tours, Tours, France
| | - François Nobili
- Unité de Néphrologie Pédiatrie, Besançon, Centre Hospitalier Universitaire de Besançon, Besançon, France
| | - Robert Novo
- Hôpital Jeanne de Flandre, Service de Néphrologie Pédiatrique, Centre Hospitalier Universitaire de Lille, Lille, France
| | - Laurence Faivre
- Centre de Génétique, Centre Hospitalier Universitaire de Dijon, Dijon, France
| | - Claire Rigothier
- Service de Néphrologie Transplantation Dialyse, Centre Hospitalier Universitaire de Bordeaux, Bordeaux, France
| | | | - Remi Salomon
- Faculté de Médecine, Université Paris Descartes, Paris, France.,Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Assistance Publique Hôpitaux de Paris, Hôpital Necker-Enfants-malades, Service de Néphrologie Pédiatrique, Paris, France
| | - Andreas Schleich
- Institute of Nephrology Statspital Waid Zuerich, Zuerich, Switzerland
| | - Anne-Laure Sellier-Leclerc
- Centre de Référence des Maladies Rénales Rares. Service de Néphrologie Rhumatologie Dermatologie Pédiatriques, Hospices Civils de Lyon, Lyon, France
| | | | - Aurélien Tiple
- Centre Hospitalier Universitaire Gabriel-Montpied Service de Néphrologie, Clermont-Ferrand, France
| | - Tim Ulinski
- Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France.,Assistance Publique-Hôpitaux de Paris, Service de Néphrologie et Transplantation Rénale, Hôpital Trousseau, Paris, France
| | - Philippe Vanhille
- Centre Hospitalier de Valenciennes, Service de Néphrologie et Médecine Interne, Valenciennes, France
| | - Nicole Van Regemorter
- Université Libre de Bruxelles, Hôpital Erasme Département de Génétique Médicale, Brussels, Belgium
| | - Xavier Jeunemaître
- Faculté de Médecine, Université Paris Descartes, Paris, France.,Assistance Publique-Hôpitaux de Paris, Service de Génétique, Hôpital Européen Georges Pompidou, Paris, France.,INSERM, UMR970, Paris-Cardiovascular Research Center, Paris, France.,Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France
| | - Rosa Vargas-Poussou
- Assistance Publique-Hôpitaux de Paris, Service de Génétique, Hôpital Européen Georges Pompidou, Paris, France.,INSERM, UMR970, Paris-Cardiovascular Research Center, Paris, France.,Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France
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9
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Saida K, Kamijo Y, Matsuoka D, Noda S, Hidaka Y, Mori T, Shimojo H, Ehara T, Miura K, Takita J, Sekine T, Igarashi T, Koike K. A case of adult Dent disease in Japan with advanced chronic kidney disease. CEN Case Rep 2013; 3:132-138. [PMID: 28509186 DOI: 10.1007/s13730-013-0102-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 10/21/2013] [Indexed: 11/26/2022] Open
Abstract
Dent disease is an inherited tubulopathy caused by a mutation in the CLCN5 chloride channel gene. In cases of Dent disease in Japan (Japanese Dent, J-Dent), renal function is generally preserved and rarely progresses to advanced kidney dysfunction. However, the long-term prognosis of J-Dent remains unknown. We report the case of a 32-year-old man with J-Dent who developed advanced kidney dysfunction. Since the age of 3 years, he persistently exhibited proteinuria, and examination of a kidney biopsy specimen indicated focal segmental glomerulosclerosis (FSGS)-like lesions. Repeated corticosteroid treatments were found to be ineffective. After the age of 18 years, the patient was lost to follow-up and treatment was discontinued. The patient presented to our hospital again at the age of 32 years with advanced kidney dysfunction with low-molecular-weight proteinuria (LMWP), along with proximal tubular dysfunction and nephrocalcinosis. The patient's 5-year-old nephew was also found to have LMWP from the age of 7 months. Therefore, Dent disease was suspected and genetic testing in the patient and his nephew revealed a CLCN5 mutation. Our case report suggests that J-Dent may cause advanced kidney dysfunction in adulthood, and, therefore, close collaboration between pediatricians and nephrologists is essential for the early identification of this complication. When male patients exhibit chronic kidney disease (CKD) of unknown etiology along with proximal tubular dysfunction and nephrocalcinosis, Dent disease should be considered. Investigations of undiagnosed adult J-Dent cases and further research on the natural history of J-Dent will help us better understand its clinical characteristics, prognosis, and effective treatment options.
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Affiliation(s)
- Ken Saida
- Department of Pediatrics, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano, Japan
| | - Yuji Kamijo
- Department of Nephrology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano, 390-8621, Japan.
| | - Daisuke Matsuoka
- Department of Pediatrics, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano, Japan
| | - Shunsuke Noda
- Department of Pediatrics, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano, Japan
| | - Yoshihiko Hidaka
- Department of Pediatrics, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano, Japan
| | - Tetsuo Mori
- Department of Pediatrics, Shinshu Ueda Medical Center, 1-27-21 Midorigaoka, Ueda, Nagano, Japan
| | - Hisashi Shimojo
- Department of Pathology, Shinshu University School of Medicine, Nagano, Japan
| | - Takashi Ehara
- Department of Pathology, Shinshu University School of Medicine, Nagano, Japan
| | - Kenichiro Miura
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Junko Takita
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan
- Department of Cell Therapy and Transplantation Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Takashi Sekine
- Department of Pediatrics, Toho University School of Medicine, Ohashi Hospital, 2-17-6 Ohashi, Meguro-ku, Tokyo, Japan
| | - Takashi Igarashi
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan
| | - Kenichi Koike
- Department of Pediatrics, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano, Japan
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10
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Sekine T, Komoda F, Miura K, Takita J, Shimadzu M, Matsuyama T, Ashida A, Igarashi T. Japanese Dent disease has a wider clinical spectrum than Dent disease in Europe/USA: genetic and clinical studies of 86 unrelated patients with low-molecular-weight proteinuria. Nephrol Dial Transplant 2013; 29:376-84. [PMID: 24081861 DOI: 10.1093/ndt/gft394] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Dent disease is an X-linked disorder characterized by low-molecular-weight (LMW) proteinuria, hypercalciuria, nephrocalcinosis, urolithiasis and renal dysfunction. Dent disease is caused by mutations in at least two genes, i.e. CLCN5 and OCRL1, and its genetic background and phenotypes are common among European countries and the USA. However, only few studies on Dent disease in Japan, which was originally called 'low-molecular-weight proteinuric disease', have been reported thus far. In this study, we analysed genetic background and clinical phenotype and laboratory data of 86 unrelated Japanese Dent disease patients. The results demonstrated that the genetic basis of Japanese Dent disease was nearly identical to those of Dent disease in other countries. Of 86 unrelated Japanese Dent patients, 61 possessed mutations in CLCN5 (Dent-1), of which 27 were novel mutations; 11 showed mutations in OCRL1 (Dent-2), six of which were novel, and the remaining 14 patients showed no mutations in CLCN5 or OCRL1 (Dent-NI). Despite the similarity in genetic background, hypercalciuria was detected in only 51%, rickets in 2% and nephrocalcinosis in 35%. Although the patients were relatively young, six patients (8%) showed apparent renal dysfunction. Japanese Dent disease has a wider clinical spectrum than Dent disease in Europe and the USA.
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Affiliation(s)
- Takashi Sekine
- Department of Pediatrics, Ohashi Hospital, Toho University School of Medicine, Tokyo, Japan
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11
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Lo YF, Nozu K, Iijima K, Morishita T, Huang CC, Yang SS, Sytwu HK, Fang YW, Tseng MH, Lin SH. Recurrent deep intronic mutations in the SLC12A3 gene responsible for Gitelman's syndrome. Clin J Am Soc Nephrol 2010; 6:630-9. [PMID: 21051746 DOI: 10.2215/cjn.06730810] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND OBJECTIVES Gitelman's syndrome (GS) is an autosomal recessive renal tubular disorder caused by mutations in the SLC12A3 gene encoding the thiazide-sensitive Na(+)-Cl(-) cotransporter (NCC). Despite meticulous sequencing of genomic DNA, approximately one-third of GS patients are negative or heterozygotes for the known mutations. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Because blood leukocytes express NCC mRNA, we evaluate whether deep intronic mutations contribute to GS patients with uniallelic or undetectable SLC12A3 mutations. Twenty-nine patients with GS (men/women = 16/13), including eight negative and 21 uniallelic SLC12A3 mutations from 19 unrelated families, and normal controls were enrolled in an academic medical center. Analysis of cDNA from blood leukocytes, sequencing of the corresponding introns of genomic DNA for abnormal transcript, and analysis of NCC protein expression from renal biopsy were performed. RESULTS We identified nine Taiwan aboriginal patients carrying c.1670-191C→T mutations in intron 13 and 10 nonaboriginal patients carrying c.2548+253C→T mutations in intron 21 from 14 families (14/19). These two mutations undetected in 100 healthy subjects created pseudoexons containing new premature termination codons. Haplotype analysis with markers flanking SLC12A3 revealed that both mutations did not have founder effects. Apical NCC expression in the DCT of renal tissue was markedly diminished in two patients carrying deep intronic mutations. CONCLUSIONS Deep intronic mutations in SLC12A3 causing defective NCC expression can be identified with the RNA-based approach in patients with GS. c.1670-191C→T and c.2548+253C→T are hot spot mutations that can be screened in GS patients with uniallelic or negative SLC12A3 mutations.
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Affiliation(s)
- Yi-Fen Lo
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
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12
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Kanda K, Nozu K, Yokoyama N, Morioka I, Miwa A, Hashimura Y, Kaito H, Iijima K, Matsuo M. Autosomal dominant pseudohypoaldosteronism type 1 with a novel splice site mutation in MR gene. BMC Nephrol 2009; 10:37. [PMID: 19912655 PMCID: PMC2779785 DOI: 10.1186/1471-2369-10-37] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 11/14/2009] [Indexed: 11/16/2022] Open
Abstract
Background Autosomal dominant pseudohypoaldosteronism type 1 (PHA1) is a rare inherited condition that is characterized by renal resistance to aldosterone as well as salt wasting, hyperkalemia, and metabolic acidosis. Renal PHA1 is caused by mutations of the human mineralcorticoid receptor gene (MR), but it is a matter of debate whether MR mutations cause mineralcorticoid resistance via haploinsufficiency or dominant negative mechanism. It was previously reported that in a case with nonsense mutation the mutant mRNA was absent in lymphocytes because of nonsense mediated mRNA decay (NMD) and therefore postulated that haploinsufficiency alone can give rise to the PHA1 phenotype in patients with truncated mutations. Methods and Results We conducted genomic DNA analysis and mRNA analysis for familial PHA1 patients extracted from lymphocytes and urinary sediments and could detect one novel splice site mutation which leads to exon skipping and frame shift result in premature termination at the transcript level. The mRNA analysis showed evidence of wild type and exon-skipped RT-PCR products. Conclusion mRNA analysis have been rarely conducted for PHA1 because kidney tissues are unavailable for this disease. However, we conducted RT-PCR analysis using mRNA extracted from urinary sediments. We could demonstrate that NMD does not fully function in kidney cells and that haploinsufficiency due to NMD with premature termination is not sufficient to give rise to the PHA1 phenotype at least in this mutation of our patient. Additional studies including mRNA analysis will be needed to identify the exact mechanism of the phenotype of PHA.
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Affiliation(s)
- Kyoko Kanda
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan.
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13
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Nozu K, Iijima K, Nozu Y, Ikegami E, Imai T, Fu XJ, Kaito H, Nakanishi K, Yoshikawa N, Matsuo M. A deep intronic mutation in the SLC12A3 gene leads to Gitelman syndrome. Pediatr Res 2009; 66:590-3. [PMID: 19668106 DOI: 10.1203/pdr.0b013e3181b9b4d3] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Many mutations have been detected in the SLC12A3 gene of Gitelman syndrome (GS, OMIM 263800) patients. In previous studies, only one mutant allele was detected in approximately 20 to 41% of patients with GS; however, the exact reason for the nonidentification has not been established. In this study, we used RT-PCR using mRNA to investigate for the first time transcript abnormalities caused by deep intronic mutation. Direct sequencing analysis of leukocyte DNA identified one base insertion in exon 6 (c.818_819insG), but no mutation was detected in another allele. We analyzed RNA extracted from leukocytes and urine sediments and detected unknown sequence containing 238bp between exons 13 and 14. The genomic DNA analysis of intron 13 revealed a single-base substitution (c.1670-191C>T) that creates a new donor splice site within the intron resulting in the inclusion of a novel cryptic exon in mRNA. This is the first report of creation of a splice site by a deep intronic single-nucleotide change in GS and the first report to detect the onset mechanism in a patient with GS and missing mutation in one allele. This molecular onset mechanism may partly explain the poor success rate of mutation detection in both alleles of patients with GS.
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Affiliation(s)
- Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan.
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14
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Bökenkamp A, Böckenhauer D, Cheong HI, Hoppe B, Tasic V, Unwin R, Ludwig M. Dent-2 disease: a mild variant of Lowe syndrome. J Pediatr 2009; 155:94-9. [PMID: 19559295 DOI: 10.1016/j.jpeds.2009.01.049] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 12/02/2008] [Accepted: 01/15/2009] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To compare the renal and extra-renal phenotypes of patients classified as having Dent disease, Dent-2 disease, or Lowe syndrome. STUDY DESIGN Chart review of data from 93 patients with identified voltage-gated chloride channel and chloride/proton antiporter 5 gene and oculo-cerebro-renal syndrome of Lowe gene mutations observed by the authors, complemented with published data. RESULTS There was a wide overlap of renal symptoms. Nephrocalcinosis was more prevalent in Dent-1 disease, and renal tubular acidosis, aminoaciduria, and renal failure was more prevalent in patients with Lowe syndrome. Patients with Lowe syndrome were shorter than patients with Dent-1 disease, and patients with Dent-2 disease showed an intermediate phenotype. Three patients with Dent-2 disease had mild peripheral cataract, and 9 patients were noted to have some degree of mental retardation. CONCLUSION There is a phenotypic continuum within patients with Dent-2 disease and Lowe syndrome, suggesting that there are individual differences in the ability to compensate for loss of oculo-cerebro-renal syndrome of Lowe gene function.
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Affiliation(s)
- Arend Bökenkamp
- Department of Pediatrics, VU University Medical Center, Amsterdam, The Netherlands.
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15
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Nozu K, Iijima K, Kawai K, Nozu Y, Nishida A, Takeshima Y, Fu XJ, Hashimura Y, Kaito H, Nakanishi K, Yoshikawa N, Matsuo M. In vivo and in vitro splicing assay of SLC12A1 in an antenatal salt-losing tubulopathy patient with an intronic mutation. Hum Genet 2009; 126:533-8. [PMID: 19513753 DOI: 10.1007/s00439-009-0697-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 05/30/2009] [Indexed: 10/20/2022]
Abstract
Type I Bartter syndrome (BS), an inherited salt-losing tubulopathy, is caused by mutations of the SLC12A1 gene. While several intronic nucleotide changes in this gene have been detected, transcriptional analysis had not been conducted because mRNA analysis is possible only when renal biopsy specimens can be obtained or occasionally when mRNA is expressed in the leukocytes. This report concerns a type I BS patient due to compound heterozygosity for the SLC12A1 gene. Genomic DNA sequencing disclosed the presence of two novel heterozygous mutations of c.724 + 4A > G in intron 5 and c.2095delG in intron 16, but it remains to be determined whether the former would be likely to influence the transcription. In this report, we conducted both in vivo assay of RT-PCR analysis using RNA extracted from the proband's urinary sediments and in vitro functional splicing study by minigene construction, and obtained evidence that this intronic mutation leads to complete exon 5 skipping. To the best of our knowledge, this is the first study to use non-invasive methods for both an in vivo assay and an in vitro functional splicing assay of inherited kidney disease. These analytical assays could be adapted for all inherited kidney diseases.
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Affiliation(s)
- Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kusunokicho 7-5-1, Chuo, Kobe, Hyogo 650-0017, Japan.
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16
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LI PENG, HUANG JIANPING. Phenotype and genotype of Dent's disease in three Chinese boys. Nephrology (Carlton) 2009; 14:139-42. [DOI: 10.1111/j.1440-1797.2008.01057.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Abstract
C1q nephropathy is a proliferative glomerulopathy with extensive mesangial deposition of C1q. A three-year old boy presented with a nephrotic-range proteinuria during an acute phase of Epstein-Barr virus (EBV) infection, and he had a family history of Dent's disease. The renal biopsy findings were compatible with C1q nephropathy. However, EBV in situ hybridization was negative. The CLCN5 gene analysis revealed an R637X hemizygous mutation, which was the same as that detected in his maternal cousin, the proband of the family. The causal relationship between EBV infection and C1q nephropathy remains to be determined. Moreover, the effects of underlying Dent's disease in the process of C1q nephropathy has to be considered.
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Affiliation(s)
- In Seok Lim
- Department of Pediatrics, Chungang University Yongsan Hospital, Seoul, Korea.
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18
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Sekine T, Nozu K, Iyengar R, Fu XJ, Matsuo M, Tanaka R, Iijima K, Matsui E, Harita Y, Inatomi J, Igarashi T. OCRL1 mutations in patients with Dent disease phenotype in Japan. Pediatr Nephrol 2007; 22:975-80. [PMID: 17384968 DOI: 10.1007/s00467-007-0454-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2006] [Revised: 01/09/2007] [Accepted: 01/10/2007] [Indexed: 12/31/2022]
Abstract
Three distinct OCRL1 mutations in three patients with the Dent disease phenotype are described. All the patients manifested an extremely high degree of low-molecular-weight proteinuria and showed no ocular abnormalities or apparent mental retardation. Urinalysis and blood chemistry showed no findings suggestive of Fanconi syndrome with renal tubular acidosis. Mutations in CLCN5 were ruled out. The mutations identified in OCRL1 are one frame-shift mutation (I127stop) and two missense mutations (R301C and R476W). R301C and R476W mutations might be hot spots in OCRL1, which develop very similar phenotypes as Dent-2.
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Affiliation(s)
- Takashi Sekine
- Department of Pediatrics, Graduate School of Medicine,The University of Tokyo, Tokyo, Japan.
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19
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Affiliation(s)
- Philip W Shaul
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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20
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Ludwig M, Utsch B, Balluch B, Fründ S, Kuwertz-Bröking E, Bökenkamp A. Hypercalciuria in patients with CLCN5 mutations. Pediatr Nephrol 2006; 21:1241-50. [PMID: 16807762 DOI: 10.1007/s00467-006-0172-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 03/26/2006] [Accepted: 03/27/2006] [Indexed: 11/27/2022]
Abstract
Hypercalciuria is regarded as a characteristic symptom of Dent disease, an X-linked recessive tubulopathy characterized by low molecular weight (LMW) proteinuria, nephrocalcinosis/nephrolithiasis, and progressive renal failure due to mutations in the CLCN5 gene. As the presence of hypercalciuria may affect the decision to consider a CLCN5 mutation in the differential diagnosis, the phenotypic spectrum and the relative frequency of hypercalciuria in patients with CLCN5 mutations was determined. We assessed renal calcium excretion in 34 male patients with proven CLCN5 mutations, who had been referred because of LMW proteinuria and at least one additional symptom of Dent disease. Hypercalciuria was defined as renal calcium excretion exceeding 0.1 mmol/kg per day. Data obtained were compared with all series of CLCN5-positive patients identified by a systematic literature survey. In 7 of our 19 families, at least 1 affected male had normal calcium excretion. Hypercalciuria was observed in 22 of 31 patients tested (71%) compared to 85 of 90 (94.4%) in series from Europe and North America and 74.4% from Japan. LMW proteinuria was present in all CLCN5-positive patients; 25% of the patients in European and North American series, 45% of the Japanese, and 41% in the present series had only two of the four principal symptoms of Dent disease. Therefore, a CLCN5 mutation should be considered irrespective of the presence of hypercalciuria in a patient with LMW proteinuria and one additional symptom of Dent disease.
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Affiliation(s)
- Michael Ludwig
- Department of Clinical Biochemistry, University of Bonn, Sigmund-Freud-Str. 25, 53105, Bonn, Germany.
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21
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Ludwig M, Utsch B, Monnens LAH. Recent advances in understanding the clinical and genetic heterogeneity of Dent's disease. Nephrol Dial Transplant 2006; 21:2708-17. [PMID: 16861240 DOI: 10.1093/ndt/gfl346] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Michael Ludwig
- Department of Clinical Biochemistry, University of Bonn, Sigmund-Freud-Strasse 25, D-53105 Bonn, Germany.
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22
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Abstract
Nephrolithiasis is responsible for 1 in 1000 to 1 in 7600 pediatric hospital admissions annually throughout the United States. Seventy-five percent of children with nephrolithiasis have an identifiable predisposition to stone formation. This article reviews the different causes and disease states associated with nephrolithiasis in the pediatric population. The initial evaluation and the metabolic evaluation of children with nephrolithiasis are reviewed. Treatment modalities for the different stone types are also described.
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Affiliation(s)
- Julie A Nicoletta
- Division of Pediatric Nephrology, Department of Pediatrics, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14624, USA.
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Cheong HI, Lee JW, Zheng SH, Lee JH, Kang JH, Kang HG, Ha IS, Lee SJ, Choi Y. Phenotype and genotype of Dent's disease in three Korean boys. Pediatr Nephrol 2005; 20:455-9. [PMID: 15719255 DOI: 10.1007/s00467-004-1769-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2004] [Revised: 11/08/2004] [Accepted: 11/09/2004] [Indexed: 10/25/2022]
Abstract
Dent's disease is a hereditary renal tubular disorder caused by mutations of the CLCN5 gene and is clinically characterized by low molecular weight proteinuria, hypercalciuria and nephrocalcinosis. This disease has been reported in several countries. However, there are some phenotypic differences between countries, such as hypophosphatemic rickets, progressive renal failure and hematuria. In this study, phenotypes were analyzed in three Korean boys with Dent's disease, and genetic diagnoses were performed using a new convenient method using peripheral blood RNA. Gene studies revealed two nonsense mutations, R637X in two patients and E609X in one patient. The phenotypes of the two patients with R637X were very similar to those of Japanese patients, i.e., they presented with asymptomatic proteinuria without rickets, renal failure or hematuria. The E609X patient was diagnosed genetically at 3 months of age before the onset of clinical symptoms because of superimposed furosemide-induced nephrolithiasis. This is the first report to characterize mutations in the CLCN5 gene in Korean patients with Dent's disease, and expands the spectrum of CLCN5 mutations by reporting a novel mutation, E609X. In addition, the mutational analysis using peripheral blood RNA can be easily applied in the clinical diagnosis.
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Affiliation(s)
- Hae Il Cheong
- Department of Pediatrics, Seoul National University Children's Hospital, 28 Yongon-dong Chongro-gu, 110-744 Seoul, Korea.
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Hoopes RR, Raja KM, Koich A, Hueber P, Reid R, Knohl SJ, Scheinman SJ. Evidence for genetic heterogeneity in Dent's disease. Kidney Int 2004; 65:1615-20. [PMID: 15086899 DOI: 10.1111/j.1523-1755.2004.00571.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Dent's disease (X-linked nephrolithiasis) is a proximal tubulopathy that has been consistently associated with inactivating mutations in the CLCN5 gene encoding the ClC-5 chloride channel expressed in tubular epithelial cells. METHODS We performed mutation analysis of the coding region of CLCN5 by DNA sequencing in 32 unrelated males, all of whom met the following three clinical criteria for the diagnosis of Dent's disease: (1) low-molecular-weight (LMW) proteinuria; (2) hypercalciuria; and (3) at least one of the following: nephrocalcinosis, kidney stones, renal insufficiency, hypophosphatemia, or hematuria. RESULTS Sixteen mutations (ten missense, four nonsense, two frameshift) were found in 19 patients. Mutations were confirmed by restriction analysis or allele-specific polymerase chain reaction (PCR), segregated with disease in the families, and were not polymorphisms. In the other 13 patients with Dent's disease, the coding sequence of CLCN5 was normal. In these 13 patients, we also sequenced two regions of the CLCN5 promoter (626 and 586 bp, respectively, 2.1 and 1 kb upstream of exon 2) containing regulatory sites [activating protein-1 (AP-1)-like, AP-4, and cyclic adenosine monophosphate (cAMP)-receptor element binding protein (CREB)] and primary and secondary transcription start sites. We found no mutations in these promoter sequences in any of the 13 patients. In one three-generation family, the absence of mutation was confirmed by sequencing in two additional affected family members, and in this family haplotype analysis excluded linkage to the region of the CLCN5 gene. There were no differences between the 19 patients with CLCN5 mutations and the 13 without mutations with regard to any clinical features of Dent's disease. CONCLUSION These findings suggest that mutation in other gene(s) may be responsible for the phenotype of Dent's disease in some patients.
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Affiliation(s)
- Richard R Hoopes
- Department of Medicine, State University of New York Upstate Medical University, Syracuse, New York 13210, USA
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Ludwig M, Waldegger S, Nuutinen M, Bökenkamp A, Reissinger A, Steckelbroeck S, Utsch B. Four additional CLCN5 exons encode a widely expressed novel long CLC-5 isoform but fail to explain Dent's phenotype in patients without mutations in the short variant. Kidney Blood Press Res 2004; 26:176-84. [PMID: 12886045 DOI: 10.1159/000071883] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2003] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Dent's disease is caused by mutations in the CLCN5 gene coding for the chloride channel CLC-5. However, sequencing of CLCN5 exonic regions in some patients presenting with low-molecular-weight proteinuria and hypercalciuria - the hallmarks of Dent's disease - failed to identify causative mutations. AIM Given the observation that some species harbour a CLCN5 mRNA encoding an extended CLC-5 aminoterminus compared with the so far known human form, we worked on the presumption that an orthologous (longer) CLCN5 transcript is also present in humans and that our patients may have mutations herein. METHODS Extensive databank mining, reverse transcription polymerase chain reaction (RT-PCR) and automated sequencing were used in the search for novel CLCN5 transcripts. The human CLCN5 gene was investigated in 7 patients out of five families by direct automated sequencing of PCR-amplified DNA products. RESULTS Two new human CLCN5 transcripts expressed in kidney and various other tissues could be identified. These arise from a novel site of transcription initiation, alternative splicing and the use of four additional CLCN5 exons. If being translated, both these mRNAs would lead to an enlarged CLC-5 protein consisting of 816 amino acids by adding 70 aminoterminal residues to the so far known 746-amino-acid-long isoform. Sequence analysis of the henceforward 17 CLCN5 exons revealed no mutation in the patients with a phenotype resembling Dent's disease. CONCLUSIONS Despite the identification of further targets to explain Dent's disease, the molecular defect in our patients remains to be elucidated. Hence, their phenotype may be explained by mutations that affect so far unknown regulating elements of the CLCN5 gene or another gene(s), probably encoding CLC-5 accessory protein(s).
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Affiliation(s)
- Michael Ludwig
- Department of Clinical Biochemistry, University of Bonn, Bonn, Germany.
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Bocca G, Monnens LAH. Defective proximal tubular function in a patient with I-cell disease. Pediatr Nephrol 2003; 18:830-2. [PMID: 12811655 DOI: 10.1007/s00467-003-1213-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2002] [Revised: 03/17/2003] [Accepted: 03/19/2003] [Indexed: 11/27/2022]
Abstract
A girl with a proven diagnosis of I-cell disease is presented. Proximal tubular dysfunction was characterized by increased excretion of low molecular proteins, aminoaciduria, hyperphosphaturia, and high/slightly increased urinary calcium. The concentration of 1,25-dihydroxycalciferol in serum was increased. Rickets were present on X-rays. As the proximal tubular dysfunction resembles the dysfunction in Dent disease, one can speculate about a common pathogenesis. Impairment of acidification in lysosomes due to loss of function of the chloride-5 channel impairs intralysosomal protease activity in Dent disease, while in I-cell disease the intralysomal protease activity is lacking.
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Affiliation(s)
- G Bocca
- Department of Pediatric Nephrology, University Medical Center St. Radboud, Nijmegen, The Netherlands
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Moulin P, Igarashi T, Van der Smissen P, Cosyns JP, Verroust P, Thakker RV, Scheinman SJ, Courtoy PJ, Devuyst O. Altered polarity and expression of H+-ATPase without ultrastructural changes in kidneys of Dent's disease patients. Kidney Int 2003; 63:1285-95. [PMID: 12631345 DOI: 10.1046/j.1523-1755.2003.00851.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Dent's disease is a proximal tubule (PT) disorder characterized by low-molecular-weight proteinuria (LWMP) that may be associated with hypercalciuria, nephrocalcinosis, and renal failure. It is caused by inactivating mutations of the renal chloride channel ClC-5, which colocalizes with the vacuolar H+-ATPase in PT cells and alpha-type intercalated cells. Examinations of knockout mice have established the role of ClC-5 in PT endocytosis, but the consequences of ClC-5 mutations on the polarity of H+-ATPase and other plasma membrane proteins remain unknown. METHODS We have studied renal biopsies from eight patients with Dent's disease, due to inactivating ClC-5 mutations, by light and electron microscopy, and by immunohistochemical staining. All patients exhibited LMWP, and renal function ranged from normal to end-stage renal failure. RESULTS Light microscopy revealed either normal renal architecture or glomerulosclerosis, tubular dedifferentiation and atrophy, and mild interstitial fibrosis. Focal, hyaline casts, sometimes calcified, were identified at all stages. Electron microscopy did not reveal any ultrastructural abnormalities in PT cells, and the endocytic apparatus was apparently normal. However, immunohistochemical studies demonstrated a consistent inversion of H+-ATPase polarity in PT cells to a basolateral distribution contrasting with its apical location in the normal kidney. This inversion of polarity was specific for H+-ATPase and did not affect distribution of aminopeptidase, megalin, and Na+/K+-ATPase. Furthermore, apical H+-ATPase expression was absent in alpha-type intercalated cells. CONCLUSION ClC-5 mutations are associated with modifications in the polarity and expression of H+-ATPase, but not ultrastructural alterations in PT cells. These findings help further understanding of the role of ClC-5 and the pathophysiology of Dent's disease.
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Affiliation(s)
- Pierre Moulin
- Division of Pathology, and Cell Unit, Christian de Duve Institute of Cellular Pathology, Université Catholique de Louvain, Brussels, Belgium
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Wu F, Roche P, Christie PT, Loh NY, Reed AAC, Esnouf RM, Thakker RV. Modeling study of human renal chloride channel (hCLC-5) mutations suggests a structural-functional relationship. Kidney Int 2003; 63:1426-32. [PMID: 12631358 DOI: 10.1046/j.1523-1755.2003.00859.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Dent's disease, a renal tubular disorder characterized by low-molecular-weight proteinuria, hypercalciuria, and nephrolithiasis, is due to inactivating mutations in the X-linked renal-specific chloride channel, hCLC-5. The x-ray crystal structures of two bacterial chloride channels (CLCs) have recently been established, thereby allowing us to construct a model for hCLC-5 and further examine the role of its mutations. METHODS The data regarding 49 hCLC-5 mutations were reviewed. Thirty-four mutations that predicted absent or truncated channels were excluded. The remaining 15 mutations (one in-frame insertion and 14 missense mutations), 12 of which have been studied electrophysiologically, were assessed. The hCLC-5 sequence was aligned with the Salmonella typhimurium and Escherichia coli sequences and used to map the hCLC-5 mutations onto a three-dimensional model. RESULTS hCLC-5 is a homodimeric protein, with each subunit consisting of 18 helices. None of the missense mutations involved the chloride (Cl-) selectivity filter, but 12 of the 15 mutations were found to be clustered at the interface of the two subunits. Six of these mutations occurred in two of the helices that either form part of the interface or lie in close proximity to the interface, and three other mutations that did not lead to complete loss of Cl- conductance were at the edge of the interface. CONCLUSION These results demonstrate a crucial role for the interaction between the two subunits at the interface of the homodimeric hCLC-5.
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Affiliation(s)
- Fiona Wu
- Molecular Endocrinology Group, Nuffield Department of Clinical Medicine, University of Oxford, Botnar Research Centre, Nuffield Orthopaedic Centre, Headington, Oxford, United Kingdom
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Yu AS. Role of ClC-5 in the pathogenesis of hypercalciuria: recent insights from transgenic mouse models. Curr Opin Nephrol Hypertens 2001; 10:415-20. [PMID: 11342807 DOI: 10.1097/00041552-200105000-00019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Dent's disease is an inherited disorder characterized by hypercalciuria, low molecular weight proteinuria, and Fanconi syndrome, which is caused by inactivating mutations in ClC-5, a chloride channel expressed in endosomes of the proximal renal tubule. The role of ClC-5 in the pathogenesis of the hypercalciuria and other myriad manifestations of this disease, however, is largely unknown. New insights from three new transgenic mouse models of Dent's disease, reported in the past year, are discussed.
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Affiliation(s)
- A S Yu
- Renal Division and Membrane Biology Program, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
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