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Zhao Z, Chen J, Jiang Y, Lu Y. The E156K mutation in the CRYAA gene affects the epithelial-mesenchymal transition and migration of human lens epithelial cells. Heliyon 2024; 10:e23690. [PMID: 38187316 PMCID: PMC10770500 DOI: 10.1016/j.heliyon.2023.e23690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 11/30/2023] [Accepted: 12/09/2023] [Indexed: 01/09/2024] Open
Abstract
Purpose To investigated the biological effects of E156K-mutated αA-crystallin (CRYAA) in human lens epithelial cells (HLECs). Methods FLAG-tagged, human, full-length, wild-type (WT), or E156K-mutated CRYAA was expressed in HLECs under CRYAA knockdown. CRYAA expression was determined by quantitative reverse transcription polymerase chain reaction and western blotting (WB). Rhodamine cytoskeleton staining was used to observe the changes in cell morphology following transfection with WT or E156K-mutated CRYAA plasmids. WB was performed to assess the expression of markers related to epithelial-mesenchymal transition (EMT) and migration. Results Rhodamine cytoskeleton staining revealed changes in the morphology of cells transfected with E156K-mutated CRYAA and opposite responses occurred after treatment with a β-catenin inhibitor. Cells transfected with E156K-mutated CRYAA expressed remarkably higher levels of the mesenchymal biomarkers N-cadherin and vimentin but decreased levels of the epithelial biomarker E-cadherin, whereas opposite trends were observed in cells treated with the β-catenin inhibitor, ICG001. The migratory capability of E156K-mutated CRYAA cells was significantly greater than that of WT cells (P < 0.001). This effect was accompanied by significantly increased expression levels of phosphorylated (p)-focal adhesion kinase (FAK) and p-Src. These changes were decreased significantly by treatment with FAK and Src inhibitors. Conclusion E156K-mutated CRYAA induced EMT, in which the HLECs lost cell polarity, and acquired a mesenchymal phenotype with greater migratory capability. These biological effects may be associated with activation of the Wnt/β-Catenin and FAK/Src signaling pathways.
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Affiliation(s)
- Zhennan Zhao
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Jiahui Chen
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yongxiang Jiang
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yi Lu
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
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2
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Zhao Z, Chen J, Yuan W, Jiang Y, Lu Y. Association between single nucleotide polymorphisms in exon 3 of the alpha-A-crystallin gene and susceptibility to age-related cataract. Ophthalmic Genet 2023; 44:127-132. [PMID: 36380611 DOI: 10.1080/13816810.2022.2092757] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND The mutations in the αA-crystallin (CRYAA) gene may contribute to the development of age-related cataract (ARC). In this study, we searched for single nucleotide polymorphisms (SNP) in exons of CRYAA and investigated the associations between the identified SNPs and the subtypes of ARC. MATERIALS AND METHODS Peripheral venous blood was collected for the extraction of genomic DNA. Three exons of CRYAA were sequenced to detect SNPs. The frequency distributions of alleles and genotypes were compared between the ARC and control groups. RESULTS There were 618 patients with various subtypes of ARC (nuclear cataract [NC], cortical cataract [CC], posterior subcapsular cataract [PSC]). The control group comprised 236 patients. The incidence of early-onset cataract was significantly greater in PSC patients (P = .002 for NC; P = .036 for CC). One SNP was detected in exon 3 of CRYAA (rs76740365 G>A). When the distribution of rs76740365 was compared among the ARC subtypes, only the difference between the PSC group and the control group was statistically significant (allele frequency: P = .000057, OR 2.945; genotype distribution frequency: P = .000458). The heterozygote genotype (GA) carried a significantly greater risk than the homozygous wild-type genotype (GG) by 1.742 times for all types of cataracts and 2.369 times for the PSC subtype. CONCLUSIONS The SNP rs76740365 G>A in exon 3 of the CRYAA gene is associated with greater susceptibility of ARC, particularly the PSC subtype. Individuals carrying the SNP rs76740365 G>A may be more likely to develop PSC at a younger age than other subtypes.
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Affiliation(s)
- Zhennan Zhao
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Jiahui Chen
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Wenyi Yuan
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yongxiang Jiang
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yi Lu
- Department of Ophthalmology and Vision Science, Eye Ear Nose and Throat Hospital of Fudan University, Shanghai, China
- National Health Commission Key Laboratory of Myopia (Fudan University), Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
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3
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Computational study of peptide interaction with mutant γ-crystallin with the aim of preventing dimerization. Struct Chem 2022. [DOI: 10.1007/s11224-022-02015-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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4
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Genetic and Clinical Studies of Peripheral Neuropathies with Three Small Heat Shock Protein Gene Variants in Korea. Genes (Basel) 2022; 13:genes13030462. [PMID: 35328016 PMCID: PMC8949397 DOI: 10.3390/genes13030462] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/02/2022] [Accepted: 03/03/2022] [Indexed: 01/25/2023] Open
Abstract
Small heat shock proteins (sHSPs) are ATP-independent chaperones that help correct the folding of denatured proteins and protect cells from stress. Mutations in HSPB1, HSPB8, and HSPB3 are implicated in inherited peripheral neuropathies (IPNs), such as Charcot-Marie-Tooth disease type 2 (CMT2) and distal hereditary motor neuropathies (dHMN). This study, using whole exome sequencing or targeted gene sequencing, identified 9 pathogenic or likely pathogenic variants in these three sHSP genes from 11 Korean IPN families. Most variants were located in the evolutionally well conserved α-crystallin domain, except for p.P182S and p.S187L in HSPB1. As an atypical case, a patient with dHMN2 showed two compound heterozygous variants of p.R127Q and p.Y142H in HSPB1, suggesting a putative case of recessive inheritance, which requires additional research to confirm. Three HSPB8 variants were located in the p.K141 residue, which seemed to be a mutational hot spot. There were no significant differences between patient groups, which divided by sHSP genes for clinical symptoms such as onset age, severity, and nerve conduction. Early-onset patients showed a tendency of slightly decreased sensory nerve conduction values compared with late-onset patients. As a first Korean IPN cohort study examining sHSP genes, these results will, we believe, be helpful for molecular diagnosis and care of patients with CMT2 and dHMN.
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Budnar P, Tangirala R, Bakthisaran R, Rao CM. Protein Aggregation and Cataract: Role of Age-Related Modifications and Mutations in α-Crystallins. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:225-241. [PMID: 35526854 DOI: 10.1134/s000629792203004x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
* The article is published as a part of the Special Issue "Protein Misfolding and Aggregation in Cataract Disorders" (Vol. 87, No. 2). ** To whom correspondence should be addressed. Cataract is a major cause of blindness. Due to the lack of protein turnover, lens proteins accumulate age-related and environmental modifications that alter their native conformation, leading to the formation of aggregation-prone intermediates, as well as insoluble and light-scattering aggregates, thus compromising lens transparency. The lens protein, α-crystallin, is a molecular chaperone that prevents protein aggregation, thereby maintaining lens transparency. However, mutations or post-translational modifications, such as oxidation, deamidation, truncation and crosslinking, can render α-crystallins ineffective and lead to the disease exacerbation. Here, we describe such mutations and alterations, as well as their consequences. Age-related modifications in α-crystallins affect their structure, oligomerization, and chaperone function. Mutations in α-crystallins can lead to the aggregation/intracellular inclusions attributable to the perturbation of structure and oligomeric assembly and resulting in the rearrangement of aggregation-prone regions. Such rearrangements can lead to the exposure of hitherto buried aggregation-prone regions, thereby populating aggregation-prone state(s) and facilitating amorphous/amyloid aggregation and/or inappropriate interactions with cellular components. Investigations of the mutation-induced changes in the structure, oligomer assembly, aggregation mechanisms, and interactomes of α-crystallins will be useful in fighting protein aggregation-related diseases.
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Affiliation(s)
- Prashanth Budnar
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Uppal Road, Hyderabad, 500007, India
| | - Ramakrishna Tangirala
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Uppal Road, Hyderabad, 500007, India
| | - Raman Bakthisaran
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Uppal Road, Hyderabad, 500007, India
| | - Ch Mohan Rao
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Uppal Road, Hyderabad, 500007, India.
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Tedesco B, Cristofani R, Ferrari V, Cozzi M, Rusmini P, Casarotto E, Chierichetti M, Mina F, Galbiati M, Piccolella M, Crippa V, Poletti A. Insights on Human Small Heat Shock Proteins and Their Alterations in Diseases. Front Mol Biosci 2022; 9:842149. [PMID: 35281256 PMCID: PMC8913478 DOI: 10.3389/fmolb.2022.842149] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 01/19/2022] [Indexed: 11/13/2022] Open
Abstract
The family of the human small Heat Shock Proteins (HSPBs) consists of ten members of chaperones (HSPB1-HSPB10), characterized by a low molecular weight and capable of dimerization and oligomerization forming large homo- or hetero-complexes. All HSPBs possess a highly conserved centrally located α-crystallin domain and poorly conserved N- and C-terminal domains. The main feature of HSPBs is to exert cytoprotective functions by preserving proteostasis, assuring the structural maintenance of the cytoskeleton and acting in response to cellular stresses and apoptosis. HSPBs take part in cell homeostasis by acting as holdases, which is the ability to interact with a substrate preventing its aggregation. In addition, HSPBs cooperate in substrates refolding driven by other chaperones or, alternatively, promote substrate routing to degradation. Notably, while some HSPBs are ubiquitously expressed, others show peculiar tissue-specific expression. Cardiac muscle, skeletal muscle and neurons show high expression levels for a wide variety of HSPBs. Indeed, most of the mutations identified in HSPBs are associated to cardiomyopathies, myopathies, and motor neuropathies. Instead, mutations in HSPB4 and HSPB5, which are also expressed in lens, have been associated with cataract. Mutations of HSPBs family members encompass base substitutions, insertions, and deletions, resulting in single amino acid substitutions or in the generation of truncated or elongated proteins. This review will provide an updated overview of disease-related mutations in HSPBs focusing on the structural and biochemical effects of mutations and their functional consequences.
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Affiliation(s)
- B. Tedesco
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - R. Cristofani
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - V. Ferrari
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - M. Cozzi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - P. Rusmini
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - E. Casarotto
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - M. Chierichetti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - F. Mina
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - M. Galbiati
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - M. Piccolella
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - V. Crippa
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - A. Poletti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
- *Correspondence: A. Poletti,
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Fox SC, Widen SA, Asai-Coakwell M, Havrylov S, Benson M, Prichard LB, Baddam P, Graf D, Lehmann OJ, Waskiewicz AJ. BMP3 is a novel locus involved in the causality of ocular coloboma. Hum Genet 2022; 141:1385-1407. [PMID: 35089417 DOI: 10.1007/s00439-022-02430-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/04/2022] [Indexed: 12/29/2022]
Abstract
Coloboma, a congenital disorder characterized by gaps in ocular tissues, is caused when the choroid fissure fails to close during embryonic development. Several loci have been associated with coloboma, but these represent less than 40% of those that are involved with this disease. Here, we describe a novel coloboma-causing locus, BMP3. Whole exome sequencing and Sanger sequencing of patients with coloboma identified three variants in BMP3, two of which are predicted to be disease causing. Consistent with this, bmp3 mutant zebrafish have aberrant fissure closure. bmp3 is expressed in the ventral head mesenchyme and regulates phosphorylated Smad3 in a population of cells adjacent to the choroid fissure. Furthermore, mutations in bmp3 sensitize embryos to Smad3 inhibitor treatment resulting in open choroid fissures. Micro CT scans and Alcian blue staining of zebrafish demonstrate that mutations in bmp3 cause midface hypoplasia, suggesting that bmp3 regulates cranial neural crest cells. Consistent with this, we see active Smad3 in a population of periocular neural crest cells, and bmp3 mutant zebrafish have reduced neural crest cells in the choroid fissure. Taken together, these data suggest that Bmp3 controls Smad3 phosphorylation in neural crest cells to regulate early craniofacial and ocular development.
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Affiliation(s)
- Sabrina C Fox
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB, T6G 2E9, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Sonya A Widen
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB, T6G 2E9, Canada.,Vienna BioCenter, Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Mika Asai-Coakwell
- Department of Animal and Poultry and Animal Science, University of Saskatchewan, Saskatoon, SK, Canada.,Department of Ophthalmology, University of Alberta, Edmonton, AB, Canada
| | - Serhiy Havrylov
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada.,Department of Ophthalmology, University of Alberta, Edmonton, AB, Canada
| | - Matthew Benson
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada.,Department of Ophthalmology, University of Alberta, Edmonton, AB, Canada
| | - Lisa B Prichard
- Department of Biological Sciences, MacEwan University, Edmonton, AB, Canada
| | - Pranidhi Baddam
- Department of Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Daniel Graf
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada.,Department of Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Ordan J Lehmann
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada.,Department of Ophthalmology, University of Alberta, Edmonton, AB, Canada
| | - Andrew J Waskiewicz
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, AB, T6G 2E9, Canada. .,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada.
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8
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Abstract
AIM Polymorphisms in alpha A crystallin (CRYAA) gene have been implicated in susceptibility to cataracts, but some published studies have reported inconclusive results. Our study aimed to conduct a meta-analysis investigating the association between polymorphisms in CRYAA and susceptibility to cataracts. METHODS The PubMed, Excerpta Medica Database, Cochrane Library and China National Knowledge Infrastructure were searched for all articles published up to 20 March 2019 that reported cataracts and three polymorphisms (rs3761381, rs13053109, and rs7278468) of CRYAA. Afterwards, statistical analysis was performed for available articles. RESULTS Four articles published between 2014 and 2017 were included, involving 869 cases and 1,950 controls. There was no statistical evidence of an association between cataract risk and CRYAA gene polymorphisms rs13053109 (p > .05) and rs3761382 (p > .05). Significant decreased cataract risks were observed for different gene models of rs7278468 polymorphism: for G vs T, OR = 0.6640; 95% CI, 0.5361-0.7736, p < .001; for GG vs TT, OR = 0.3864; 95% CI, 0.2379-0.6278, p < .001; for GG vs TT+GT, OR = 0.4492; 95% CI, 0.2829-0.7134, p = .001; for GG+GT vs TT, OR = 0.6645; 95% CI, 0.5058-0.8729, p = .003; for GT vs TT, OR = 0.7508; 95% CI, 0.5639-0.9996, p = .050. CONCLUSION Our meta-analysis indicated that rs3761382 and rs13053109 polymorphisms of CRYAA may not be associated with susceptibility to cataracts. Individuals carrying mutant genotype of rs7278468 polymorphism are associated with a significantly decreased cataract risk. ABBREVIATIONS CC: Congenital cataract; ARC: Age-related cataract; SNPs: single nucleotide polymorphisms; NOS: Newcastle-Ottawa Scale; HWE: Hardy-Weinberg equilibrium; OR: odds ratio; CI: confidence interval; qPCR: quantitative polymerase chain reaction; NO: nuclear opalescence; NC: nuclear color.
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Affiliation(s)
- Hongtao Yu
- Department of Ophthalmology, First Affiliated Hospital of Soochow University, Soochow, Jiangsu, China.,Department of Ophthalmology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu, China
| | - Kaifeng Liu
- Department of Urology, Northern Jiangsu People's Hospital (NJPH), Clinical Medical School of Yangzhou University, Yangzhou, Jiangsu, PR China
| | - Peirong Lu
- Department of Ophthalmology, First Affiliated Hospital of Soochow University, Soochow, Jiangsu, China
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Phadte AS, Mahalingam S, Santhoshkumar P, Sharma KK. Functional Rescue of Cataract-Causing αA-G98R-Crystallin by Targeted Compensatory Suppressor Mutations in Human αA-Crystallin. Biochemistry 2019; 58:4148-4158. [PMID: 31523965 DOI: 10.1021/acs.biochem.9b00374] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The G98R mutation in αA-crystallin is associated with the onset of presenile cataract and is characterized biochemically by an increased oligomeric mass, altered chaperone function, and loss of structural stability over time. Thus, far, it is not known whether the inherent instability caused by gain-of-charge mutation could be rescued by a compensatory loss of charge mutation elsewhere on the protein. To answer this question, we investigated whether αA-G98R-mediated instability could be rescued through suppressor mutations by introducing site-specific "compensatory" mutations in αA-G98R-crystallin, αA-R21Q/G98R, αA-G98R/R116C, and αA-R157Q/G98R. The recombinant proteins were expressed, purified, characterized, and evaluated by circular dichroism (CD), intrinsic fluorescence, and bis-ANS-binding studies. Chaperone-like activities of recombinant proteins were assessed using alcohol dehydrogenase (ADH) and insulin as unfolding substrates. Far-UV CD studies revealed an increased α-helical content in αA-G98R in comparison to αA-WT, αA-R21Q, R157Q, and the double mutants, αA-R21Q/G98R, and αA-R157Q/G98R. Compared to αA-WT, αA-R21Q, and αA-G98R, the double mutants showed an increased intrinsic tryptophan fluorescence, whereas the highest hydrophobicity (bis-ANS-binding) was shown by αA-G98R. Introduction of a second mutation in αA-G98R reduced its bis-ANS-binding activity. Both αA-R21Q/G98R and αA-R157Q/G98R showed greater chaperone-like activity against ADH aggregation than αA-G98R. However, among the three G98R mutants, only αA-R21Q/G98R protected ARPE-19 cells from H2O2-induced cytotoxicity. These results suggest that the lost chaperone-like activity of αA-G98R-crystallin can be rescued by another targeted mutation and that substitution of αA-R21Q-crystallin at the N-terminal region can rescue a deleterious mutation in the conserved α-crystallin domain of the protein.
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Affiliation(s)
- Ashutosh S Phadte
- Department of Ophthalmology , University of Missouri School of Medicine , Columbia , Missouri 65212 , United States.,Department of Biochemistry , University of Missouri , Columbia , Missouri 65212 , United States
| | - Sundararajan Mahalingam
- Department of Ophthalmology , University of Missouri School of Medicine , Columbia , Missouri 65212 , United States
| | - Puttur Santhoshkumar
- Department of Ophthalmology , University of Missouri School of Medicine , Columbia , Missouri 65212 , United States
| | - Krishna K Sharma
- Department of Ophthalmology , University of Missouri School of Medicine , Columbia , Missouri 65212 , United States.,Department of Biochemistry , University of Missouri , Columbia , Missouri 65212 , United States
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10
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The Role of the Arginine in the Conserved N-Terminal Domain RLFDQxFG Motif of Human Small Heat Shock Proteins HspB1, HspB4, HspB5, HspB6, and HspB8. Int J Mol Sci 2018; 19:ijms19072112. [PMID: 30036999 PMCID: PMC6073470 DOI: 10.3390/ijms19072112] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 07/14/2018] [Accepted: 07/17/2018] [Indexed: 11/17/2022] Open
Abstract
Although the N-terminal domain of vertebrate small heat shock proteins (sHsp) is poorly conserved, it contains a core motif preserved in many members of the sHsp family. The role of this RLFDQxFG motif remains elusive. We analyzed the specific role of the first arginine residue of this conserved octet sequence in five human sHsps (HspB1, HspB4, HspB5, HspB6, and HspB8). Substitution of this arginine with an alanine induced changes in thermal stability and/or intrinsic fluorescence of the related HspB1 and HspB8, but yielded only modest changes in the same biophysical properties of HspB4, HspB5, and HspB6 which together belong to another clade of vertebrate sHsps. Removal of the positively charged Arg side chain resulted in destabilization of the large oligomers of HspB1 and formation of smaller size oligomers of HspB5. The mutation induced only minor changes in the structure of HspB4 and HspB6. In contrast, the mutation in HspB8 was accompanied by shifting the equilibrium from dimers towards the formation of larger oligomers. We conclude that the RLFDQxFG motif plays distinct roles in the structure of several sHsp orthologs. This role correlates with the evolutionary relationship of the respective sHsps, but ultimately, it reflects the sequence context of this motif.
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11
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Phadte AS, Santhoshkumar P, Sharma KK. Characterization of an N-terminal mutant of αA-crystallin αA-R21Q associated with congenital cataract. Exp Eye Res 2018; 174:185-195. [PMID: 29782825 DOI: 10.1016/j.exer.2018.05.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 04/06/2018] [Accepted: 05/16/2018] [Indexed: 01/20/2023]
Abstract
Several mutations associated with congenital cataracts in human beings target conserved arginine residues in αA-crystallin. The N-terminal region of αA-crystallin is a "mutational hotspot," with multiple cataract-related mutations reported in this region. Two mutations at arginine 21 in the N-terminal domain of αA-crystallin - αA-R21L and αA-R21W have been associated with congenital cataract. A third mutant of R21, αA-R21Q, was recently identified to be associated with congenital cataract in a South Australian family. The point mutation was reported to compromise the quaternary structure of αA-crystallin by preventing its assembly into higher ordered oligomers. To assess the effect of the αA-R21Q mutation on αA-crystallin function, recombinant αA-R21Q was expressed, purified and characterized in vitro. Compared to wild-type αA-crystallin, the recombinant αA-R21Q exhibits enhanced chaperone-like activity, increased surface hydrophobicity, lesser stability in urea and increased susceptibility to digestion by trypsin. αA-R21Q demonstrated increased binding affinity towards unfolding ADH and bovine lens fiber cell membranes. αA-R21Q homo-oligomers and hetero-oligomers also prevented H2O2-induced apoptosis in ARPE-19 cells. Taken together, αA-R21Q exhibited a gain of function despite subtle structural differences as compared to wild-type αA-crystallin. This study further validates the involvement of arginine 21 in regulating αA-crystallin structure and function.
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Affiliation(s)
- Ashutosh S Phadte
- Department of Ophthalmology, University of Missouri School of Medicine, Columbia, MO 65212, United States; Department of Biochemistry, University of Missouri, Columbia, MO 65211, United States
| | - Puttur Santhoshkumar
- Department of Ophthalmology, University of Missouri School of Medicine, Columbia, MO 65212, United States
| | - K Krishna Sharma
- Department of Ophthalmology, University of Missouri School of Medicine, Columbia, MO 65212, United States; Department of Biochemistry, University of Missouri, Columbia, MO 65211, United States.
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Fluorescent Protein Visualization Immediately After Gel Electrophoresis Using an In-Gel Trichloroethanol Photoreaction with Tryptophan. Methods Mol Biol 2018; 1853:179-190. [PMID: 30097944 DOI: 10.1007/978-1-4939-8745-0_22] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
SDS-polyacrylamide gel electrophoresis (SDS-PAGE) is one of the essential techniques in molecular biology and biochemistry laboratories and requires rapid visualization methods for efficient sample analysis. Proteins on polyacrylamide gels can be visualized within 5 min via the photoreaction of tryptophan with trichloroethanol. This process does not require protein fixation, staining, or destaining. In this method polyacrylamide gels are prepared by adding trichloroethanol before polymerization. After electrophoresis, the gel is immediately activated on a standard UV transilluminator and the fluorescently labeled proteins are imaged. The reaction is based on the photoreaction of trichloroethanol with tryptophan residues within the protein. This generates a visible blue-green fluorescence (∼500 nm) that is accurately imaged. Here we describe the preparation of Tris-glycine and Tris-tricine SDS-polyacrylamide gels with trichloroethanol and the photoreaction and visualization of tryptophan containing proteins.
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Two novel mutations identified in ADCC families impair crystallin protein distribution and induce apoptosis in human lens epithelial cells. Sci Rep 2017; 7:17848. [PMID: 29259299 PMCID: PMC5736644 DOI: 10.1038/s41598-017-18222-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 12/07/2017] [Indexed: 01/20/2023] Open
Abstract
Congenital cataract (CC) is a clinical and genetically heterogeneous eye disease that primarily causes lens disorder and even amblyopic blindness in children. As the mechanism underlying CC is genetically inherited, identification of CC-associated gene mutations and their role in protein distribution are topics of both pharmacological and biological research. Through physical and ophthalmic examinations, two Chinese pedigrees with autosomal dominant congenital cataract (ADCC) were recruited for this study. Mutation analyses of CC candidate genes by next-generation sequencing (NGS) and Sanger sequencing revealed a novel missense mutation in CRYBB2 (p.V146L) and a deletion mutation in CRYAA (p.116_118del). Both mutations fully co-segregated were not observed in unaffected family members or in 100 unrelated healthy controls. The CRYBB2 missense mutation disrupts the distribution of CRYBB2 in human lens epithelial cells (HLEpiCs), and the CRYAA deletion mutation causes hyperdispersion of CRYAA. Furthermore, these two crystallin mutations result in aberrant expression of unfolded protein response (UPR) marker genes as well as apoptosis in HLEpiCs. Collectively, these findings broaden the genetic spectrum of ADCC.
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Zhu X, Zhang S, Chang R, Lu Y. New cataract markers: Mechanisms of disease. Clin Chim Acta 2017; 472:41-45. [PMID: 28705775 DOI: 10.1016/j.cca.2017.07.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/08/2017] [Accepted: 07/09/2017] [Indexed: 11/28/2022]
Abstract
Cataract is caused by nutritional, metabolic, environmental, and genetic factors, and is a significant cause of blindness and visual impairment. In recent years, extensive research into the human genome has revealed that numerous genetic mutations are associated with cataract. These mutations affect a variety of genes, including those encoding crystallin, membrane proteins, cytoskeletal proteins, transcription factors, and metabolism-related proteins. Elucidation of these mutations and the genetic and molecular mechanisms has helped clarify the etiology of cataract and may facilitate its early diagnosis and treatment. This review summarizes recent advances in our knowledge and potential clinical of genetic markers of cataract.
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Affiliation(s)
- Xiangjia Zhu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Shaohua Zhang
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Ruiqi Chang
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Yi Lu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China.
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Cui XJ, Lv FY, Li FH, Zeng K. Correlations of single nucleotide polymorphisms of CRYAA and CRYAB genes with the risk and clinicopathological features of children suffering from congenital cataract. Medicine (Baltimore) 2017; 96:e7158. [PMID: 28640093 PMCID: PMC5484201 DOI: 10.1097/md.0000000000007158] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The study aims to explore the correlations of the single nucleotide polymorphisms (SNPs) of CRYAA and CRYAB with the risk and clinicopathological features of children with congenital cataract. METHODS The study enrolled 168 children diagnosed as congenital cataract (case group) and 172 normal children (control group) from May 2015 to May 2016. Genomic DNA extraction was performed using a QIAamp DNA blood mini kit. Polymerase chain reaction (PCR) products were genotyped using an ABI direct sequencer. Haplotype, allele, and genotype frequencies of CRYAA and CRYAB gene polymorphisms analyses were carried out using the SHEsis software. Logistic regression analysis was performed in order to analyze the risk factors for children suffering from congenital cataract. RESULTS Presence of significant differences between the case and control groups' genotype and allele frequencies of CRYAA rs7278468 and CRYAB rs370803064/rs387907338. TA of CRYAB gene might increase congenital cataract risk in children, while GCG of CRYAA gene and GC of CRYAB gene might decrease congenital cataract risk in children. CRYAA rs7278468, CRYAB rs370803064/rs387907338 polymorphisms were significantly correlated to uncorrected visual acuity, best-corrected visual acuity, nystagmus, visual axis opacification, microcornea, lens opacity, posterior capsular thickening, and degrees of posterior capsule opacification after operation in children with congenital cataract. Logistic regression analysis revealed that the T allele of CRYAA rs7278468, A allele of CRYAB rs370803064, T allele of CRYAB rs387907338, family history, and TA haplotype of CRYAB gene were risk factors for children with congenital cataract. CONCLUSION Our findings demonstrated that CRYAA rs7278468 and CRYAB rs370803064/rs387907338 are correlated with the risk and clinicopathological features of children suffering from congenital cataract.
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Affiliation(s)
- Xian-Jin Cui
- Department of Ophthalmology, Linyi People's Hospital
| | - Feng-Yan Lv
- Department of Infectious Diseases, Affiliated Hospital of Shandong Medical College, Linyi
| | - Feng-Hua Li
- Department of Ophthalmology, Linyi People's Hospital
| | - Kun Zeng
- Shenzhen Key Laboratory of Ophthalmology, Shenzhen Eye Hospital, Shenzhen, P.R. China
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16
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Messina-Baas O, Cuevas-Covarrubias SA. Inherited Congenital Cataract: A Guide to Suspect the Genetic Etiology in the Cataract Genesis. Mol Syndromol 2017; 8:58-78. [PMID: 28611546 DOI: 10.1159/000455752] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2016] [Indexed: 01/23/2023] Open
Abstract
Cataracts are the principal cause of treatable blindness worldwide. Inherited congenital cataract (CC) shows all types of inheritance patterns in a syndromic and nonsyndromic form. There are more than 100 genes associated with cataract with a predominance of autosomal dominant inheritance. A cataract is defined as an opacity of the lens producing a variation of the refractive index of the lens. This variation derives from modifications in the lens structure resulting in light scattering, frequently a consequence of a significant concentration of high-molecular-weight protein aggregates. The aim of this review is to introduce a guide to identify the gene involved in inherited CC. Due to the manifold clinical and genetic heterogeneity, we discarded the cataract phenotype as a cardinal sign; a 4-group classification with the genes implicated in inherited CC is proposed. We consider that this classification will assist in identifying the probable gene involved in inherited CC.
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Javadiyan S, Craig JE, Souzeau E, Sharma S, Lower KM, Pater J, Casey T, Hodson T, Burdon KP. Recurrent mutation in the crystallin alpha A gene associated with inherited paediatric cataract. BMC Res Notes 2016; 9:83. [PMID: 26867756 PMCID: PMC4750205 DOI: 10.1186/s13104-016-1890-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 01/27/2016] [Indexed: 12/18/2022] Open
Abstract
Background Cataract is a major cause of childhood blindness worldwide. The purpose of this study was to determine the genetic cause of paediatric cataract in a South Australian family with a bilateral lamellar paediatric cataract displaying variable phenotypes. Case presentation Fifty-one genes implicated in congenital cataract in human or mouse were sequenced in an affected individual from an Australian (Caucasian) family using a custom Ampliseq library on the Ion Torrent Personal Genome Machine. Reads were mapped against the human genome (hg19) and variants called with the Torrent Suite software. Variants were annotated to dbSNP 137 using Ion Reporter (IR 1.6.2) and were prioritised for validation if they were novel or rare and were predicted to be protein changing. We identified a previously reported oligomerization disrupting mutation, c.62G > A (p.R21Q), in the Crystallin alpha A (CRYAA) gene segregating in this three generation family. No other novel or rare coding mutations were detected in the known cataract genes sequenced. Microsatellite markers were used to compare the haplotypes between the family reported here and a previously published family with the same segregating mutation. Haplotype analysis indicated a potential common ancestry between the two South Australian families with this mutation. The work strengthens the genotype-phenotype correlations between this functional mutation in the crystallin alpha A (CRYAA) gene and paediatric cataract. Conclusion The p.R21Q mutation is the most likely cause of paediatric cataract in this family. The recurrence of this mutation in paediatric cataract families is likely due to a familial relationship. Electronic supplementary material The online version of this article (doi:10.1186/s13104-016-1890-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shari Javadiyan
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Jamie E Craig
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Emmanuelle Souzeau
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Shiwani Sharma
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Karen M Lower
- Department of Haematology and Genetic Pathology, School of Medicine, Flinders University, Adelaide, Australia.
| | - John Pater
- Ophthalmology Department, Women's and Children's Hospital, Adelaide, Australia.
| | - Theresa Casey
- Ophthalmology Department, Women's and Children's Hospital, Adelaide, Australia.
| | | | - Kathryn P Burdon
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia. .,Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia.
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Panda AK, Nandi SK, Chakraborty A, Nagaraj RH, Biswas A. Differential role of arginine mutations on the structure and functions of α-crystallin. Biochim Biophys Acta Gen Subj 2015; 1860:199-210. [PMID: 26080000 DOI: 10.1016/j.bbagen.2015.06.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/22/2015] [Accepted: 06/09/2015] [Indexed: 11/29/2022]
Abstract
BACKGROUND α-Crystallin is a major protein of the eye lens in vertebrates. It is composed of two subunits, αA- and αB-crystallin. α-Crystallin is an oligomeric protein having these two subunits in 3:1 ratio. It belongs to small heat shock protein family and exhibits molecular chaperone function, which plays an important role in maintaining the lens transparency. Apart from chaperone function, both subunits also exhibit anti-apoptotic property. Comparison of their primary sequences reveals that αA- and αB-crystallin posses 13 and 14 arginine residues, respectively. Several of them undergo mutations which eventually lead to various eye diseases such as congenital cataract, juvenile cataract, and retinal degeneration. Interestingly, many arginine residues of these subunits are modified during glycation and even some are truncated during aging. All these facts indicate the importance of arginine residues in α-crystallin. SCOPE OF REVIEW In this review, we will emphasize the recent in vitro and in vivo findings related to congenital cataract causing arginine mutations in α-crystallin. MAJOR CONCLUSIONS Congenital cataract causing arginine mutations alters the structure and decreases the chaperone function of α-crystallin. These mutations also affect the lens morphology and phenotypes. Interestingly, non-natural arginine mutations (generated for mimicking the glycation and truncation environment) improve the chaperone function of α-crystallin which may play an important role in maintaining the eye lens transparency during aging. GENERAL SIGNIFICANCE The neutralization of positive charge on the guanidino group of arginine residues is not always detrimental to the functionality of α-crystallin. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease.
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Affiliation(s)
- Alok Kumar Panda
- School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 751013, India
| | - Sandip Kumar Nandi
- School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 751013, India
| | - Ayon Chakraborty
- School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 751013, India
| | - Ram H Nagaraj
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Ashis Biswas
- School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 751013, India.
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Andley UP, Goldman JW. Autophagy and UPR in alpha-crystallin mutant knock-in mouse models of hereditary cataracts. Biochim Biophys Acta Gen Subj 2015; 1860:234-9. [PMID: 26071686 DOI: 10.1016/j.bbagen.2015.06.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND Knock-in mice provide useful models of congenital and age-related cataracts caused by α-crystallin mutations. R49C αA-crystallin and R120G αB-crystallin mutations are linked with hereditary cataracts. Knock-in αA-R49C+/- heterozygotes develop cataracts by 1-2months, whereas homozygote mice have cataracts at birth. The R49C mutation drastically reduces lens protein water solubility and causes cell death in knock-in mouse lenses. Mutant crystallin cannot function as a chaperone, which leads to protein aggregation and lens opacity. Protein aggregation disrupts the lens fiber cell structure and normal development and causes cell death in epithelial and fiber cells. We determined what aspects of the wild-type phenotype are age-dependently altered in the mutant lens. METHODS Wild-type, heterozygote (αA-R49C+/-), and homozygote (αA-R49C+/+) mouse lenses were assessed pre- and postnatally for lens morphology (electron microscopy, immunohistochemistry), and autophagy or unfolded protein response markers (immunoblotting). RESULTS Morphology was altered by embryonic day 17 in R49C+/+ lenses; R49C+/- lens morphology was unaffected at this stage. Active autophagy in the lens epithelium of mutant lenses was indicated by the presence of autophagosomes using electron microscopy. Protein p62 levels, which are degraded specifically by autophagy, increased in αA-R49C mutant versus wild-type lenses, suggesting autophagy inhibition in the mutant lenses. The unfolded protein response marker XBP-1 was upregulated in adult lenses of αB-R120G+/+ mice, suggesting its role in lens opacification. CONCLUSIONS Mutated crystallins alter lens morphology, autophagy, and stress responses. GENERAL SIGNIFICANCE Therapeutic modulation of autophagic pathways may improve protein degradation in cataractous lenses and reduce lens opacity. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease.
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Affiliation(s)
- Usha P Andley
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Joshua W Goldman
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
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Ramkumar S, Thankappan B, Fujii N, Natarajaseenivasan K, Anbarasu K. Interaction of αA-crystallin F71L mutant with wild type αA- and αB-crystallins by mammalian two hybrid assay. Int J Biol Macromol 2015; 76:102-8. [DOI: 10.1016/j.ijbiomac.2015.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 02/13/2015] [Accepted: 02/16/2015] [Indexed: 11/26/2022]
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21
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Der Perng M, Quinlan RA. The Dynamic Duo of Small Heat Proteins and IFs Maintain Cell Homeostasis, Resist Cellular Stress and Enable Evolution in Cells and Tissues. HEAT SHOCK PROTEINS 2015. [DOI: 10.1007/978-3-319-16077-1_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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22
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Deng H, Yuan L. Molecular genetics of congenital nuclear cataract. Eur J Med Genet 2013; 57:113-22. [PMID: 24384146 DOI: 10.1016/j.ejmg.2013.12.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Accepted: 12/22/2013] [Indexed: 01/28/2023]
Abstract
A cataract is defined as opacification of the normally transparent crystalline lens. Congenital cataract (CC) is a type of cataract that presents at birth or during early childhood. CC is one of the most common causes of visual impairment or blindness in children worldwide. Approximately 50% of all CC cases may have a genetic cause which is quite heterogeneous. CC occurs in a variety of morphologic configurations, including polar/subcapsular, nuclear, lamellar, sutural, cortical, membranous/capsular and complete. Nuclear cataract refers to the opacification limited to the embryonic and/or fetal nuclei of the lens. Although congenital nuclear cataract can be caused by multiple factors, genetic mutation remains to be the most common cause. It can be inherited in one of the three patterns: autosomal dominant, autosomal recessive, or X-linked transmission. Autosomal dominant inheritance is the most frequent mode with high penetrance. There may be no obvious correlation between the genotype and phenotype of congenital nuclear cataract. Animal models have been established to study the pathogenesis of congenital nuclear cataract and to identify candidate genes. In this review, we highlight identified genetic mutations that account for congenital nuclear cataract. Our review may be helpful for genetic counseling and prenatal diagnosis.
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Affiliation(s)
- Hao Deng
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Tongzipo Road 138, Changsha, Hunan 410013, China.
| | - Lamei Yuan
- Center for Experimental Medicine and Department of Neurology, the Third Xiangya Hospital, Central South University, Tongzipo Road 138, Changsha, Hunan 410013, China
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Posch A, Kohn J, Oh K, Hammond M, Liu N. V3 stain-free workflow for a practical, convenient, and reliable total protein loading control in western blotting. J Vis Exp 2013:50948. [PMID: 24429481 DOI: 10.3791/50948] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The western blot is a very useful and widely adopted lab technique, but its execution is challenging. The workflow is often characterized as a "black box" because an experimentalist does not know if it has been performed successfully until the last of several steps. Moreover, the quality of western blot data is sometimes challenged due to a lack of effective quality control tools in place throughout the western blotting process. Here we describe the V3 western workflow, which applies stain-free technology to address the major concerns associated with the traditional western blot protocol. This workflow allows researchers: 1) to run a gel in about 20-30 min; 2) to visualize sample separation quality within 5 min after the gel run; 3) to transfer proteins in 3-10 min; 4) to verify transfer efficiency quantitatively; and most importantly 5) to validate changes in the level of the protein of interest using total protein loading control. This novel approach eliminates the need of stripping and reprobing the blot for housekeeping proteins such as β-actin, β-tubulin, GAPDH, etc. The V3 stain-free workflow makes the western blot process faster, transparent, more quantitative and reliable.
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