1
|
Kishnani PS, Al-Hertani W, Balwani M, Göker-Alpan Ö, Lau HA, Wasserstein M, Weinreb NJ, Grabowski G. Screening, patient identification, evaluation, and treatment in patients with Gaucher disease: Results from a Delphi consensus. Mol Genet Metab 2022; 135:154-162. [PMID: 34972655 DOI: 10.1016/j.ymgme.2021.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 02/06/2023]
Abstract
Several guidelines are available for identification and management of patients with Gaucher disease, but the most recent guideline was published in 2013. Since then, there have been significant advances in newborn screening, phenotypic characterization, identification of biomarkers and their integration into clinical practice, and the development and approval of new treatment options. Accordingly, the goal of this Delphi consensus exercise was to extend prior initiatives of this type by addressing issues related to newborn screening, diagnostic evaluations, and treatment (both disease directed and adjunctive). The iterative Delphi process involved creation of an initial slate of statements, review by a steering committee, and three rounds of consensus development by an independent panel. A preliminary set of statements was developed by the supporting agency based on literature searches covering the period from 1965 to 2020. The Delphi process reduced an initial set of 185 statements to 65 for which there was unanimous support from the panel. The statements supported may ultimately provide a framework for more detailed treatment guidelines. In addition, the statements for which unanimous support could not be achieved help to identify evidence gaps that are targets for future research.
Collapse
Affiliation(s)
- Priya S Kishnani
- Duke University Medical Center, Department of Molecular Genetics and Microbiology, 905 Lasalle Street, GSRB1, 4th Floor, Durham, NC 27710, USA.
| | - Walla Al-Hertani
- Harvard Medical School, Boston Children's Hospital, Department of Pediatrics, Division of Genetics and Genomics, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Manisha Balwani
- Icahn School of Medicine at Mount Sinai, Division of Medical Genetics and Genomics, Department of Genetics and Genomic Sciences, 1428 Madison Avenue, 1st Floor, New York, NY 10029, USA
| | - Özlem Göker-Alpan
- Lysosomal & Rare Disorders Research & Treatment Center, 3702 Pender Drive, Suite 170, Fairfax, VA 22030, USA
| | - Heather A Lau
- Ultragenyx Pharmaceutical Inc., Global Clinical Development, 840 Memorial Drive, Cambridge, MA 02139, USA
| | - Melissa Wasserstein
- The Children's Hospital at Montefiore and the Albert Einstein College of Medicine, Division of Pediatric Genetic Medicine, Departments of Pediatrics and Genetics, 3411 Wayne Ave, 9th Floor, Bronx, NY 10467, USA
| | - Neal J Weinreb
- University of Miami Miller School of Medicine, Departments of Human Genetics and Medicine, Hematology Division, 7367 Wexford Terrace, Boca Raton, FL 33433, USA
| | - Gregory Grabowski
- University of Cincinnati College of Medicine, Department of Pediatrics, and Department of Molecular Genetics, Biochemistry and Microbiology, Division of Human Genetics, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH, USA
| |
Collapse
|
2
|
Ye B, Fan C, Shen Y, Wang Q, Hu H, Xiang M. The Antioxidative Role of Autophagy in Hearing Loss. Front Neurosci 2019; 12:1010. [PMID: 30686976 PMCID: PMC6333736 DOI: 10.3389/fnins.2018.01010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 12/17/2018] [Indexed: 01/01/2023] Open
Abstract
Autophagy, a highly conserved cellular mechanism, plays an essential role in the development and pathology of many central and peripheral nervous system diseases. The auditory system, especially hair cells (HCs) and spiral ganglion neurons (SGNs) in the inner ear, are postmitotic cells, which are extremely reliant on cellular homeostasis and energy supply. Therefore, autophagy may be involved in contributing to and facilitating the normal function of inner ear cells. Recently, studies on hearing loss induced by ototoxic drugs, noise exposure and other factors have revealed that autophagy could serve in an antioxidative capacity and could possess the potential to treat sensorineural hearing loss (SNHL). Therefore, here we review previous studies concerning autophagy and SNHL to gain insight into the role of autophagic mechanisms in inner ear disorders.
Collapse
Affiliation(s)
- Bin Ye
- Department of Otolaryngology & Head and Neck Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Cui Fan
- Department of Otolaryngology & Head and Neck Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Yilin Shen
- Department of Otolaryngology & Head and Neck Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Quan Wang
- Department of Otolaryngology & Head and Neck Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Haixia Hu
- Department of Otolaryngology & Head and Neck Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Mingliang Xiang
- Department of Otolaryngology & Head and Neck Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| |
Collapse
|
3
|
Genotypes and phenotypes in 20 Chinese patients with type 2 Gaucher disease. Brain Dev 2018; 40:876-883. [PMID: 29934114 DOI: 10.1016/j.braindev.2018.06.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/13/2018] [Accepted: 06/08/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND Gaucher disease (GD) is one of the most common lysosomal storage diseases resulting from a deficiency of glucocerebrosidase. Three main types have been described, with type 2 being the most rare and severe form. Here we investigated the clinical symptoms and mutation spectrum in 20 unrelated type 2 GD patients. METHOD The diagnosis of GD was based on the acid β-glucocerebrosidase (GBA) enzyme activity and direct sequencing of the GBA gene. GBA activity was measured in leukocytes and the GBA gene was amplified by a polymerase chain reaction (PCR). For patient 7, the GBA gene was analyzed by PCR as well as quantitative real-time PCR. RESULTS The age of onset was under 12 months for all patients. All patients experienced severe neurological involvement. A total of 19 different GBA gene mutations were identified, including 6 novel mutations: two were exonic point mutations, c.1127T > C (p.Phe376Ser), c.1418T > G (p.Val473Gly); one was splicing error, ISV7-1G > C; one was insertion, c.717_718insACAG; and the other two were a gross deletion that involved exon 6 and a recombinant allele. The most prevalent mutation was Leu483Pro, which constituted 42.5% of all mutant alleles and was associated with a neurological form in Chinese GD patients as calculated by a Fisher's exact test. CONCLUSION The clinical characteristics of Chinese type 2 GD were consistent with reports from other ethnic populations. We identified 6 novel mutations that contribute to the spectrum of GBA gene mutations. Our study confirmed that GD patients with the Leu483Pro allele were prone to experience neurological symptoms.
Collapse
|
4
|
Successful newborn screening for Gaucher disease using fluorometric assay in China. J Hum Genet 2017; 62:763-768. [PMID: 28356566 PMCID: PMC5537412 DOI: 10.1038/jhg.2017.36] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/08/2016] [Accepted: 03/02/2017] [Indexed: 01/27/2023]
Abstract
Gaucher disease (GD) is an inherited metabolic disorder that involves accumulation of glycolipid glucocerebroside in monocyte–macrophage cells, which can result in multiple organ damage. Enzyme replacement and substrate reduction therapies have improved the potential for early diagnosis and treatment. Determining the true incidence of this rare disease is critical for relevant policy establishment. Newborn screening allows for early diagnosis and an comparatively accurate incidence of GD. A fluorometric method to detect acid β-glucocerebrosidase (GBA) activity on a dried blood spot punch was developed. Validity and feasibility of the fluorometric method was demonstrated by examining 116 healthy controls, 19 confirmed GD patients and 19 obligate carriers. GBA activity was measured on dried blood spots of 80 855 newborns. Samples from positively screened newborns were reanalyzed by a leukocyte GBA activity test and GBA gene analysis. Plasma glucosylsphingosine level was determined as a biomarker of the pathophysiology of GD. GD patients were distinguished from healthy controls and obligate carriers using the fluorometric method. Mean GBA activity in newborn screening specimens was 145.69±44.76 μmol l−1 h−1 (n=80 844). Three children had low GBA activity, of which one child had low GBA activity on the second dried blood spot specimen. Leukocyte, genetic and biomarker analysis confirmed the diagnosis and indicated that this child was in the early stages of GD. In conclusion, the incidence of GD in Shanghai of China is approximately 1 in 80 855. Screening for GD by fluorometric analysis of GBA activity is an efficient and feasible technology in newborns.
Collapse
|
5
|
|
6
|
Weiss K, Gonzalez A, Lopez G, Pedoeim L, Groden C, Sidransky E. The clinical management of Type 2 Gaucher disease. Mol Genet Metab 2015; 114:110-122. [PMID: 25435509 PMCID: PMC4312716 DOI: 10.1016/j.ymgme.2014.11.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 11/06/2014] [Accepted: 11/07/2014] [Indexed: 12/12/2022]
Abstract
Gaucher disease, the inherited deficiency of the enzyme glucocerebrosidase, is the most common of the lysosomal storage disorders. Type 2 Gaucher disease, the most severe and progressive form, manifests either prenatally or in the first months of life, followed by death within the first years of life. The rarity of the many lysosomal storage disorders makes their diagnosis a challenge, especially in the newborn period when the focus is often on more prevalent illnesses. Thus, a heightened awareness of the presentation of these rare diseases is necessary to ensure their timely consideration. This review, designed to serve as a guide to physicians treating newborns and infants with Gaucher disease, discusses the presenting manifestations of Type 2 Gaucher disease, the diagnostic work-up, associated genotypes and suggestions for management. We also address the ethical concerns that may arise with this progressive and lethal disorder, since currently available treatments may prolong life, but do not impact the neurological manifestations of the disease.
Collapse
Affiliation(s)
- Karin Weiss
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ashley Gonzalez
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Grisel Lopez
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Leah Pedoeim
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Catherine Groden
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ellen Sidransky
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
7
|
Cherif W, Ben Turkia H, Ben Rhouma F, Riahi I, Chemli J, Amaral O, Sá Miranda MC, Caillaud C, Kaabachi N, Tebib N, Abdelhak S, Ben Dridi MF. [Molecular diagnosis of Gaucher disease in Tunisia]. PATHOLOGIE-BIOLOGIE 2013; 61:59-63. [PMID: 22542428 DOI: 10.1016/j.patbio.2012.03.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 03/20/2012] [Indexed: 01/30/2023]
Abstract
Gaucher disease is a lysosomal storage disorder caused by a deficiency of the enzyme acid β-glucosidase. In order to determine the mutation spectrum in Tunisia, we performed recurrent mutation screening in 30 Tunisian patients with Gaucher disease. Screening of recurrent mutation by PCR/RFLP and direct sequencing had shown that N370S was the most frequent mutation (22/50 mutant alleles, 44%), followed by L444P mutation, which is found in 16% (8/50 mutant alleles). The recombinant allele (RecNciI) represented 14%. Our findings revealed that the genotype N370S/RecNciI was mosst frequent in patients with childhood onset and it was associated with severe visceral involvement. The screening of these three mutations provided a simple tool for molecular diagnosis of Gaucher disease in Tunisian patients and allowed also genetic counselling for their family members.
Collapse
Affiliation(s)
- W Cherif
- Unité de recherche « exploration moléculaire des maladies orphelines d'origine génétique », institut Pasteur de Tunis, BP 74, 13, place Pasteur, Belvédère, 1002 Tunis, Tunisie.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Lee S, Kim HJ, Jeong SY, Hwang JM. Ocular Abnormality of Korean Patients with Molecular Genetically Confirmed Gaucher Disease. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2013. [DOI: 10.3341/jkos.2013.54.1.131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Sangmoon Lee
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hyon J. Kim
- Department of Medical Genetics, Ajou University School of Medicine, Suwon, Korea
| | - Seon-Yong Jeong
- Department of Medical Genetics, Ajou University School of Medicine, Suwon, Korea
| | - Jeong-Min Hwang
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| |
Collapse
|
9
|
Park HW, Lee Y, Kim GH, Lee BS, Kim KS, Yoo HW, Kim EAR. Novel frameshift mutation (Pro171fsX21) in neonatal type 2 Gaucher's disease. Gene 2012; 507:170-3. [PMID: 22772462 DOI: 10.1016/j.gene.2012.06.090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 06/24/2012] [Accepted: 06/26/2012] [Indexed: 10/28/2022]
Abstract
Gaucher's disease is caused by a deficiency of glucocerebrosidase (GBA) and results in the accumulation of glucocerebroside within macrophages. We report on a 33(+2) gestational week premature infant whose family history was significant for a previously undiagnosed premature sibling with similar clinical features, including severe hydrops fetalis, hepatosplenomegaly, skin lesions at birth followed by death. The diagnosis of Gaucher's disease type 2 in the present case was based on postmortem pathological findings and a subsequent gene analysis that indicated a heterozygous condition for the novel deletion mutation at GBA cDNA nucleotide position 630 resulting in the frameshift (Pro171fsX21) in exon 6 and a G→A transition mutation at GBA cDNA nucleotide position 887 (Arg257Gln) in exon 7.
Collapse
Affiliation(s)
- Hye Won Park
- Department of Pediatrics, Konkuk University Hospital, Konkuk University School of Medicine, Korea.
| | | | | | | | | | | | | |
Collapse
|
10
|
Liou B, Grabowski GA. Is E326K glucocerebrosidase a polymorphic or pathological variant? Mol Genet Metab 2012; 105:528-9. [PMID: 22227325 DOI: 10.1016/j.ymgme.2011.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 12/01/2011] [Indexed: 11/30/2022]
|
11
|
El-Morsy Z, Khashaba MT, Soliman OES, Yahia S, El-Hady DA. Glucosidase acid beta gene mutations in Egyptian children with Gaucher disease and relation to disease phenotypes. World J Pediatr 2011; 7:326-30. [PMID: 21633851 DOI: 10.1007/s12519-011-0309-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 12/09/2010] [Indexed: 10/18/2022]
Abstract
INTRODUCTION More than 200 mutations have been found in patients with Gaucher disease (GD) and some mutations usually have a high frequency in certain populations. Genotype/phenotype correlation in patients with GD has not been established. This study was designed to determine underlying mutations in Egyptian children with GD and to assess their relation to disease phenotypes. METHODS This study comprised 17 patients with GD and 10 healthy controls. Thirteen patients were type 1 GD, 2 type 2, and 2 type 3. DNA was extracted from peripheral blood leukocytes. Exons 9 and 10 were amplified by polymerase chain reaction, and deoxyribonucleic acid sequencing was done with an ABI 310 genetic analyzer. RESULTS Wild type allele was detected in 95% (19/20) and a normal variant in 5% (1/20) of controls. L444P allele was encountered in 50% (13/26) of the alleles in type 1 patients, H451P in 7.7% (2/26) and recombinant alleles (RecNcil, RecNcil + M450L, RecFs, RecFs + M450L) in 34.6% (9/26). L444P and Rec alleles each occurred in 50% (2/4) of type 2 and 3 patients. A new mutation was seen in this study {g.7336A>C, (M450L)} and 2 mutant alleles were not determined. Type 1 GD patients had L444P/L444P genotype (23.1%) and Rec alleles/L444P (53.8%), while type 2 and 3 GD patients had Rec alleles/L444P genotypes (100%) with a poor phenotype/genotype correlation. CONCLUSIONS L444P and Rec alleles are common in the studied patients. Novel mutations are continuously detected, adding to the expanding panel of GD mutations. No significant genotype-phenotype association was observed.
Collapse
Affiliation(s)
- Zakarya El-Morsy
- Department of Pediatrics, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | | | | | | | | |
Collapse
|
12
|
Horowitz M, Pasmanik-Chor M, Ron I, Kolodny EH. The enigma of the E326K mutation in acid β-glucocerebrosidase. Mol Genet Metab 2011; 104:35-8. [PMID: 21831682 DOI: 10.1016/j.ymgme.2011.07.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 07/03/2011] [Accepted: 07/03/2011] [Indexed: 10/18/2022]
Abstract
A large number of mutations, and several polymorphisms, have been characterized in the GBA gene, encoding the lysosomal enzyme glucocerebrosidase, the activity of which is impaired in Gaucher disease. In this communication we summarize published and new data concerning biochemical characterization of the E326K amino acid change (1093G>A in the GBA1 cDNA) in tissue culture and its association with Parkinson disease, suggesting it is a disease causing mutation and not merely a polymorphism in the GBA gene.
Collapse
Affiliation(s)
- Mia Horowitz
- Department of Cell Research and Immunology, Tel Aviv University, Ramat Aviv, 69978, Israel.
| | | | | | | |
Collapse
|
13
|
Type 2 Gaucher disease: phenotypic variation and genotypic heterogeneity. Blood Cells Mol Dis 2010; 46:75-84. [PMID: 20880730 DOI: 10.1016/j.bcmd.2010.08.012] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 08/24/2010] [Indexed: 11/21/2022]
Abstract
Gaucher disease (GD), the most common lysosomal storage disease, results from a deficiency of the lysosomal enzyme glucocerebrosidase. GD has been classified into 3 types, of which type 2 (the acute neuronopathic form) is the most severe, presenting pre- or perinatally, or in the first few months of life. Traditionally, type 2 GD was considered to have the most uniform clinical phenotype when compared to other GD subtypes. However, case studies over time have demonstrated that type 2 GD, like types 1 and 3, manifests with a spectrum of phenotypes. This review includes case reports that illustrate the broad range of clinical presentations encountered in type 2 GD, as well as a discussion of associated manifestations, pathological findings, diagnostic techniques, and a review of current therapies. While type 2 GD is generally associated with severe mutations in the glucocerebrosidase gene, there is also significant genotypic heterogeneity.
Collapse
|
14
|
Liou B, Grabowski GA. Participation of asparagine 370 and glutamine 235 in the catalysis by acid beta-glucosidase: the enzyme deficient in Gaucher disease. Mol Genet Metab 2009; 97:65-74. [PMID: 19217815 PMCID: PMC2699545 DOI: 10.1016/j.ymgme.2009.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Accepted: 01/07/2009] [Indexed: 11/26/2022]
Abstract
The hydrolysis of glucosylceramide by acid beta-glucosidase proceeds via a two-step, double displacement mechanism that includes cleavage of the O-beta-glucosidic bond, enzyme-glucosylation and, then, enzyme-deglucosylation. Two residues that may impact this cycle are N370 and E235. The N370S mutant enzyme is very common in Gaucher disease type 1 patients. Homology and crystal data predictions suggested that E235 is the acid/base catalyst in the hydrolytic reaction. Here, the roles of N370 and E235 in hydrolysis were explored using mutant proteins with selected amino acid substitutions. Heterologously expressed enzymes were characterized using inhibitors, activators, and alternative substrates to gain insight into the effects on the glucosylation (single turnover) and deglucosylation (transglucosylation) steps in catalysis. Specific substitutions at N370 selectively altered only the glucosylation step whereas N370S altered this and the deglucosylation steps. To provide functional data to support E235 as the acid/base catalyst, progress curves with poor substrates with more acidic leaving groups were used in the presence and absence of azide as an exogenous nucleophile. The restoration of E235G activity to nearly wild-type levels was achieved using azide with 2,4-dinitrophenyl-beta-glucoside as substrate. The loss of the acidic arm of the pH optimum activity curve of E235G provided additional functional support for E235 as the acid/base in catalysis. This study provides insight into the function of these residues in acid beta-glucosidase active site function.
Collapse
Affiliation(s)
- Benjamin Liou
- The Children’s Hospital Research Foundation of Cincinnati Children’s Hospital Medical Center, Division and Program in Human Genetics, 3333 Burnet Avenue, ML 4006, Cincinnati, OH 45229-3039
| | - Gregory A. Grabowski
- The Children’s Hospital Research Foundation of Cincinnati Children’s Hospital Medical Center, Division and Program in Human Genetics, 3333 Burnet Avenue, ML 4006, Cincinnati, OH 45229-3039
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio
| |
Collapse
|
15
|
Hruska KS, LaMarca ME, Scott CR, Sidransky E. Gaucher disease: mutation and polymorphism spectrum in the glucocerebrosidase gene (GBA). Hum Mutat 2008; 29:567-83. [DOI: 10.1002/humu.20676] [Citation(s) in RCA: 463] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
16
|
Chabás A, Gort L, Díaz-Font A, Montfort M, Santamaría R, Cidrás M, Grinberg D, Vilageliu L. Perinatal lethal phenotype with generalized ichthyosis in a type 2 Gaucher disease patient with the [L444P;E326K]/P182L genotype: effect of the E326K change in neonatal and classic forms of the disease. Blood Cells Mol Dis 2006; 35:253-8. [PMID: 15967693 DOI: 10.1016/j.bcmd.2005.04.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Accepted: 04/27/2005] [Indexed: 11/29/2022]
Abstract
Gaucher disease, the most common lysosomal storage disorder, encompasses a wide spectrum of clinical symptoms. The perinatal lethal form is very rare and is considered a distinct form of classic type 2 Gaucher disease. Prominent features of the severe perinatal form are hepatosplenomegaly variable, associated with hydrops fetalis and ichthyosis. Here, we describe a child who presented generalized ichthyosis and died at 25 days of age. Genotype analysis revealed compound heterozygosity for the complex allele [L444P;E326K] and mutation P182L, described for the first time in this patient. Mutations E326K and L444P were on the same chromosome. Expression studies of mutant glucocerebrosidases showed that the double mutant allele had lower activity, 8.5% of wild type, in contrast to the activity of individual E326K and L444P mutant enzymes, 42.7% and 14.1%, respectively. The P182L mutant enzyme showed no glucocerebrosidase activity. A revision of the genotypes identified in a series of Spanish patients with type 2 Gaucher disease showed that the complex allele [L444P;E326K] accounted for 19.2% of patient alleles and that homozygosity for this allele or its heterozygosity with mutation L444P, or another severe mutation such as P182L, was associated with the perinatal lethal presentation of the disease. In contrast, the [L444P;E326K] allele was not detected in patients with classic type 2 diagnosed when several months old. The high frequency of the E326K substitution observed in patients with type 2 as compared to the general population (0.5%) suggests that this change may have a modulating negative effect on the clinical condition of these Gaucher disease patients when present in combination with mutation L444P. The relatively high prevalence of the double mutant allele in Spanish patients prompted us to perform a haplotype analysis, using four polymorphic markers, which suggest a common origin for this allele. During the mutational analysis of the series of type 2 patients, a novel mutation, I260T (c.896T>C), was identified.
Collapse
Affiliation(s)
- Amparo Chabás
- Institut de Bioquímica Clínica, Corporació Sanitària Clínic, Mejía Lequerica, s/n. Edifici Helios III, planta baixa. 08028 Barcelona, Spain.
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Liou B, Kazimierczuk A, Zhang M, Scott CR, Hegde RS, Grabowski GA. Analyses of variant acid beta-glucosidases: effects of Gaucher disease mutations. J Biol Chem 2005; 281:4242-53. [PMID: 16293621 DOI: 10.1074/jbc.m511110200] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Acid beta-glucosidase (GCase) is a 497-amino acid, membrane-associated lysosomal exo-beta-glucosidase whose defective activity leads to the Gaucher disease phenotypes. To move toward a structure/function map for disease mutations, 52 selected single amino acid substitutions were introduced into GCase, expressed in an insect cell system, purified, and characterized for basic kinetic, stability, and activator response properties. The variant GCases from Gaucher disease patients and selected variant GCases from the mouse had decreased relative k(cat) and differential effects on active site binding and/or attachment of mechanism-based covalent (conduritol B epoxide) or reversible (deoxynojirimycin derivatives) inhibitors. A defect in negatively charged phospholipid activation was present in the majority of variant GCases but was increased in two, N370S and V394L. Deficits in saposin C enhancement of k(cat) were present in variant GCases involving residues 48-122, whereas approximately 2-fold increases were obtained with the L264I GCase. About 50% of variant GCases each had wild-type or increased sensitivity to in vitro cathepsin D digestion. Mapping of these properties onto the crystal structures of GCase indicated wide dispersion of functional properties that can affect catalytic function and stability. Site-directed mutagenesis of cysteine residues showed that the disulfide bonds, Cys(4)-Cys(16) and Cys(18)-Cys(23), and a free Cys(342) were essential for activity; the free Cys(126) and Cys(248) were not. Relative k(cat) was highly sensitive to a His substitution at Arg(496) but not at Arg(495). These studies and high phylogenetic conservation indicate localized and general structural effects of Gaucher disease mutations that were not obvious from the nature of the amino acid substitution, including those predicted to be nondisruptive (e.g. Val --> Leu). These results provide initial studies for the engineering of variant GCases and, potentially, molecular chaperones for therapeutic use.
Collapse
Affiliation(s)
- Benjamin Liou
- Division and Program in Human Genetics, Children's Hospital Research Foundation, Cincinnati, OH 45229, USA
| | | | | | | | | | | |
Collapse
|
18
|
Ron I, Dagan A, Gatt S, Pasmanik-Chor M, Horowitz M. Use of fluorescent substrates for characterization of Gaucher disease mutations. Blood Cells Mol Dis 2005; 35:57-65. [PMID: 15916907 DOI: 10.1016/j.bcmd.2005.03.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Accepted: 03/22/2005] [Indexed: 11/22/2022]
Abstract
Gaucher disease results from impaired activity of the lysosomal enzyme beta-glucocerebrosidase. More than 200 mutations within the glucocerebrosidase gene have been associated with this disease. In this study we tested the effect of several mutations (K157Q, D140H, E326K, D140H+E326K, V394L and R463C) on RNA stability, protein stability and activity toward four different fluorescent substrates (LR-12-GC, Bodipy-12-GC, LR-0-PAP-glucose and 4-MUG), using the vaccinia-derived expression system. The results indicated that the K157Q mutation leads to RNA instability, causing low protein levels and a concomitant reduction in beta-glucocerebrosidase activity. All other tested mutations led to production of glucocerebrosidase RNA and protein with stabilities comparable to those of the normal counterpart. The D140H variant exhibited a high activity toward the tested substrates while the variant enzymes containing either the E326K or D140H and E326k mutations together expressed low beta-glucocerebrosidase activity. The V394L variant exhibited low activity toward the tested substrates, while a higher activity was presented by the R463C containing glucocerebrosidase variant. Our results strongly indicated that the LR-12-GC substrate distinguishes between severities of different mutant glucocerebrosidase variants overexpressed in a heterologous system.
Collapse
Affiliation(s)
- Idit Ron
- Department of Cell Research and Immunology, Tel Aviv University, Ramat Aviv, 69978, Israel
| | | | | | | | | |
Collapse
|
19
|
Beutler E, Gelbart T, Scott CR. Hematologically important mutations: Gaucher disease. Blood Cells Mol Dis 2005; 35:355-64. [PMID: 16185900 DOI: 10.1016/j.bcmd.2005.07.005] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 07/12/2005] [Indexed: 11/22/2022]
Affiliation(s)
- Ernest Beutler
- The Scripps Research Institute, Department of Molecular and Experimental Medicine, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | | | | |
Collapse
|
20
|
Montfort M, Chabás A, Vilageliu L, Grinberg D. Functional analysis of 13 GBA mutant alleles identified in Gaucher disease patients: Pathogenic changes and "modifier" polymorphisms. Hum Mutat 2004; 23:567-75. [PMID: 15146461 DOI: 10.1002/humu.20043] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Gaucher disease, the most prevalent sphingolipidosis, is caused by the deficient activity of acid beta-glucosidase, mainly due to mutations in the GBA gene. Over 200 mutations have been identified worldwide, more than 25 of which were in Spanish patients. In order to demonstrate causality for Gaucher disease, some of them: c.662C>T (p.P182L), c.680A>G (p.N188S), c.886C>T (p.R257X), c.1054T>C (p.Y313H), c.1093G>A (p.E326K), c.1289C>T (p.P391L), c.1292A>T (p.N392I), c.1322T>C (p.I402T), and the double mutants [c.680A>G; c.1093G>A] ([p.N188S; p.E326K]) and [c.1448T>C; c.1093G>A] ([p.L444P; p.E326K]), were expressed in Sf9 cells using a baculovirus expression system. Other well-established Gaucher disease mutations, namely c.1226A>G (p.N370S), c.1342G>C (p.D409H), and c.1448T>C (p.L444P), were also expressed for comparison. The levels of residual acid beta-glucosidase activity of the mutant enzymes produced by the cDNAs carrying alleles c.662C>T (p.P182L), c.886C>T (p.R257X), c.1054T>C (p.Y313H), c.1289C>T (p.P391L), and c.1292A>T (p.N392I) were negligible. The c.1226A>G (p.N370S), c.1322T>C (p.I402T), c.1342G>C (p.D409H), c.1448T>C (p.L444P), and [c.1448T>C; c.1093G>A] ([p.L444P; p.E326K]) alleles produced enzymes with levels ranging from 6 to 14% of the wild-type. The three remaining alleles, c.680A>G (p.N188S), c.1093G>A (p.E326K), and [c.680A>G; c.1093G>A] ([p.N188S; p.E326K]), showed higher activity (66.6, 42.7, and 23.2%, respectively). Expression studies revealed that the c.1093G>A (p.E326K) change, which was never found alone in a Gaucher disease-causing allele, when found in a double mutant such as [c.680A>G; c.1093G>A] ([p.N188S; p.E326K]) and [c.1448T>C; c.1093G>A] ([p.L444P; p.E326K]), decreases activity compared to the activity found for the other mutation alone. These results suggest that c.1093G>A (p.E326K) should be considered a "modifier variant" rather than a neutral polymorphism, as previously considered. Mutation c.680A>G (p.N188S), which produces a mutant enzyme with the highest level of activity, is probably a very mild mutation or another "modifier variant."
Collapse
Affiliation(s)
- Magda Montfort
- Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | | | | | | |
Collapse
|