1
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Greiling TM, Clark JM, Clark JI. The significance of growth shells in development of symmetry, transparency, and refraction of the human lens. FRONTIERS IN OPHTHALMOLOGY 2024; 4:1434327. [PMID: 39100140 PMCID: PMC11294239 DOI: 10.3389/fopht.2024.1434327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Accepted: 06/27/2024] [Indexed: 08/06/2024]
Abstract
Human visual function depends on the biological lens, a biconvex optical element formed by coordinated, synchronous generation of growth shells produced from ordered cells at the lens equator, the distal edge of the epithelium. Growth shells are comprised of straight (St) and S-shaped (SSh) lens fibers organized in highly symmetric, sinusoidal pattern which optimizes both the refractile, transparent structure and the unique microcirculation that regulates hydration and nutrition over the lifetime of an individual. The fiber cells are characterized by diversity in composition and age. All fiber cells remain interconnected in their growth shells throughout the life of the adult lens. As an optical element, cellular differentiation is constrained by the physical properties of light and its special development accounts for its characteristic symmetry, gradient of refractive index (GRIN), short range transparent order (SRO), and functional longevity. The complex sinusoidal structure is the basis for the lens microcirculation required for the establishment and maintenance of image formation.
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Affiliation(s)
- Teri M. Greiling
- Department of Dermatology, School of Medicine, Oregon Health & Science University, Portland, OR, United States
| | - Judy M. Clark
- Department of Biological Structure, University of Washington, Seattle, WA, United States
| | - John I. Clark
- Department of Biological Structure, University of Washington, Seattle, WA, United States
- Department of Biological Structure & Ophthalmology, School of Medicine, University of Washington, Seattle, WA, United States
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2
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Reyes LP, Reyes TC, Dueñas Z, Duran D, Perdomo S, Avila MY. Expression of oxysterols in human lenses: Implications of the sterol pathway in age-related cataracts. J Steroid Biochem Mol Biol 2023; 225:106200. [PMID: 36272497 DOI: 10.1016/j.jsbmb.2022.106200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 11/06/2022]
Abstract
Lanosterol, an oxysterol molecule, has been proposed to help maintain lens transparency by inhibiting the formation of protein aggregates. This sterol is produced by the enzyme lanosterol synthase and is part of a metabolic pathway that forms cholesterol as a final step. Abnormalities in lanosterol synthase are responsible for congenital cataracts. The αA-crystallin protein, which acts as a molecular chaperone to lanosterol synthase, has been reported to have anti-protein aggregation, anti-inflammatory and anti-apoptotic properties. In this work, we evaluated the correlation of lanosterol synthase and αA-crystallin in human cataractous lenses with the grade of opacity, as well as the expression of lanosterol synthase, farnesyl DPP, geranyl synthase and squalene epoxidase genes. Lanosterol synthase and αA-crystallin were overexpressed in cataractous lenses as well as farnesyl-DP synthase, squalene epoxidase, lanosterol synthase and geranyl synthase genes in cataratous lenses in comparison with normal lenses. Our data confirm that lanosterol synthase and the sterol pathway are upregulated in cataractous lenses. This argues for a functional role of the oxysterol pathway and its products as an important mediator in the pathogenesis of human cataracts.
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Affiliation(s)
- Laura P Reyes
- Department of Ophthalmology, School of Medicine, Universidad Nacional de Colombia, Colombia
| | - Tatiana C Reyes
- Department of Ophthalmology, School of Medicine, Universidad Nacional de Colombia, Colombia; Department of Physiology, School of Medicine, Universidad Nacional de Colombia, Colombia
| | - Zulma Dueñas
- Department of Physiology, School of Medicine, Universidad Nacional de Colombia, Colombia
| | - Diego Duran
- Department of Ophthalmology, School of Medicine, Universidad Nacional de Colombia, Colombia
| | | | - Marcel Y Avila
- Department of Ophthalmology, School of Medicine, Universidad Nacional de Colombia, Colombia.
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3
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Muranov KO, Ostrovsky MA. Biochemistry of Eye Lens in the Norm and in Cataractogenesis. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:106-120. [PMID: 35508906 DOI: 10.1134/s0006297922020031] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 06/14/2023]
Abstract
The absence of cellular organelles in fiber cells and very high cytoplasmic protein concentration (up to 900 mg/ml) minimize light scattering in the lens and ensure its transparency. Low oxygen concentration, powerful defense systems (antioxidants, antioxidant enzymes, chaperone-like protein alpha-crystallin, etc.) maintain lens transparency. On the other hand, the ability of crystallins to accumulate age-associated post-translational modifications, which reduce the resistance of lens proteins to oxidative stress, is an important factor contributing to the cataract formation. Here, we suggest a mechanism of cataractogenesis common for the action of different cataractogenic factors, such as age, radiation, ultraviolet light, diabetes, etc. Exposure to these factors leads to the damage and death of lens epithelium, which allows oxygen to penetrate into the lens through the gaps in the epithelial layer and cause oxidative damage to crystallins, resulting in protein denaturation, aggregation, and formation of multilamellar bodies (the main cause of lens opacification). The review discusses various approaches to the inhibition of lens opacification (cataract development), in particular, a combined use of antioxidants and compounds enhancing the chaperone-like properties of alpha-crystallin. We also discuss the paradox of high efficiency of anti-cataract drugs in laboratory settings with the lack of their clinical effect, which might be due to the late use of the drugs at the stage, when the opacification has already formed. A probable solution to this situation will be development of new diagnostic methods that will allow to predict the emergence of cataract long before the manifestation of its clinical signs and to start early preventive treatment.
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Affiliation(s)
- Konstantin O Muranov
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119334, Russia.
| | - Mikhail A Ostrovsky
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119334, Russia
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4
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Twum K, Bhattacharjee A, Laryea ET, Esposto J, Omolloh G, Mortensen S, Jaradi M, Stock NL, Schileru N, Elias B, Pszenica E, McCormick TM, Martic S, Beyeh NK. Functionalized resorcinarenes effectively disrupt the aggregation of αA66-80 crystallin peptide related to cataracts. RSC Med Chem 2021; 12:2022-2030. [PMID: 35028562 PMCID: PMC8672818 DOI: 10.1039/d1md00294e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/13/2021] [Indexed: 11/21/2022] Open
Abstract
Cataracts, an eye lens clouding disease, are debilitating and while operable, remain without a cure. αA66-80 crystallin peptide abundant in cataracted eye lenses contributes to aggregation of αA-crystallin protein leading to cataracts. Inspired by the versatility of macrocycles and programmable guest selectivity through discrete functionalizations, we report on three water-soluble ionic resorcinarene receptors (A, B, and C) that disrupt the aggregation of αA66-80 crystallin peptide. A and B each possess four anionic sulfonate groups, while C includes four cationic ammonium groups with four flexible extended benzyl groups. Through multiple non-covalent attractions, these receptors successfully disrupt and reverse the aggregation of αA66-80 crystallin peptide, which was studied through spectroscopic, spectrometric, calorimetric, and imaging techniques. The αA66-80·receptor complexes were also explored using molecular dynamics simulation, and binding energies were calculated. Even though each of the three receptors can bind with the peptide, receptor C was characterized by the highest binding energy and affinity for three different domains of the peptide. In effect, the most efficient inhibitor was a cationic receptor C via extended aromatic interactions. These results highlight the potential of versatile and tunable functionalized resorcinarenes as potential therapeutics to reverse the aggregation of α-crystallin dominant in eye cataracts.
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Affiliation(s)
- Kwaku Twum
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
| | - Avik Bhattacharjee
- Department of Chemistry, Portland State University 1710 SW 10th Ave Portland OR 97201 USA
| | - Erving T Laryea
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
| | - Josephine Esposto
- Department of Forensic Science and Environmental and Life Sciences Program, Trent University ON K9 L0G2 Canada
| | - George Omolloh
- Department of Chemistry, Portland State University 1710 SW 10th Ave Portland OR 97201 USA
| | - Shaelyn Mortensen
- Department of Forensic Science and Environmental and Life Sciences Program, Trent University ON K9 L0G2 Canada
| | - Maya Jaradi
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
| | - Naomi L Stock
- Water Quality Centre, Trent University ON K9L 0G2 Canada
| | - Nicholas Schileru
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
- Department of Osteopathic Medicine, Midwestern University 555 31st St. Downers Grove IL 60515 USA
| | - Bianca Elias
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
| | - Elan Pszenica
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
| | - Theresa M McCormick
- Department of Chemistry, Portland State University 1710 SW 10th Ave Portland OR 97201 USA
| | - Sanela Martic
- Department of Forensic Science and Environmental and Life Sciences Program, Trent University ON K9 L0G2 Canada
- Water Quality Centre, Trent University ON K9L 0G2 Canada
| | - Ngong Kodiah Beyeh
- Department of Chemistry, Oakland University 146 Library Drive Rochester MI 48309-4479 USA
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5
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Chen X, Xu J, Chen X, Yao K. Cataract: Advances in surgery and whether surgery remains the only treatment in future. ADVANCES IN OPHTHALMOLOGY PRACTICE AND RESEARCH 2021; 1:100008. [PMID: 37846393 PMCID: PMC10577864 DOI: 10.1016/j.aopr.2021.100008] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/27/2021] [Accepted: 10/12/2021] [Indexed: 10/18/2023]
Abstract
Background Cataract is the world's leading eye disease that causes blindness. The prevalence of cataract aged 40 years and older is approximately 11.8%-18.8%. Currently, surgery is the only way to treat cataracts. Main Text From early intracapsular cataract extraction to extracapsular cataract extraction, to current phacoemulsification cataract surgery, the incision ranges from 12 to 3 mm, and sometimes to even 1.8 mm or less, and the revolution in cataract surgery is ongoing. Cataract surgery has transformed from vision recovery to refractive surgery, leading to the era of refractive cataract surgery, and premium intraocular lenses (IOLs) such as toric IOLs, multifocal IOLs, and extended depth-of-focus IOLs are being increasingly used to meet the individual needs of patients. With its advantages of providing better visual acuity and causing fewer complications, phacoemulsification is currently the mainstream cataract surgery technique worldwide. However, patient expectations for the safety and accuracy of the operation are continually increasing. Femtosecond laser-assisted cataract surgery (FLACS) has entered the public's field of vision. FLACS is a combination of new laser technology and artificial intelligence to replace fine manual clear corneal incision, capsulorhexis, and nuclear pre-fragmentation, providing new alternative technologies for patients and ophthalmologists. As FLACS matures, it is being increasingly applied in complex cases; however, some think it is not cost-effective. Although more than 26 million cataract surgeries are performed each year, there is still a gap in the prevalence of cataracts, especially in developing countries. Although cataract surgery is a nearly ideal procedure and complications are manageable, both patients and doctors dream of using drugs to cure cataracts. Is surgery really the only way to treat cataracts in the future? It has been verified by animal experiments that lanosterol therapy in rabbits and dogs could make cataract severity alleviated and lens transparency partially recovered. Although there is still much to learn about cataract reversal, this groundbreaking work provided a new strategy for the prevention and treatment of cataracts. Conclusions Although cataract surgery is nearly ideal, it is still insufficient, we expect the prospects for cataract drugs to be bright.
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Affiliation(s)
- Xinyi Chen
- Eye Center, Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China
| | - Jingjie Xu
- Eye Center, Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China
| | - Xiangjun Chen
- Eye Center, Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China
| | - Ke Yao
- Eye Center, Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China
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6
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Affiliation(s)
- Andrzej Grzybowski
- Professor of Ophthalmology, Department of Ophthalmology, University of Warmia and Mazury, Olsztyn, Poland; Institute for Research in Ophthalmology, Poznan, Poland
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7
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Abstract
Cataracts, the leading cause of vision impairment worldwide, arise from abnormal aggregation of lens proteins. According to the World Health Organization, cataracts cause more than 40% of blindness cases. As the population ages, the prevalence of cataracts will increase rapidly. Although cataract surgery is regarded as effective, it still suffers from complications and high cost, and could not meet the increasingly surgery demand. Therefore, pharmacological treatment for cataracts is a cheaper and more readily available option for patients, which is also a hot topic for years. Anti-cataract drug screening was previously mainly based on the specific pathogenic factors: oxidative stress, excess of quinoid substances, and aldose reductase (AR) activation. And several anti-cataract drugs have been applied in the clinic, while the effect is still unsatisfied. Makley and Zhao recently identified two kinds of novel pharmacological substances (25-hydroxycholesterol, lanosterol) that can reverse lens opacity by dissolving the aggregation of crystallin proteins, indicating that protein aggregation is not an endpoint and could be reversed with specific small-molecule drugs, significantly boosting the development of the cataract pharmacopeia and being regarded as a new dawn for cataract treatment. Our team built a novel optimized platform and had screened several potential therapeutic agents from a collection of lanosterol derivatives. In this review, we would mainly focus on the advancement of cataract pharmacotherapy based on the targets for anti-cataract drugs.
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Affiliation(s)
- Jingjie Xu
- Eye Center of the Second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou, China
| | - Qiuli Fu
- Eye Center of the Second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou, China
| | - Xiangjun Chen
- Eye Center of the Second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou, China.,Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Ke Yao
- Eye Center of the Second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou, China
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8
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Berry V, Georgiou M, Fujinami K, Quinlan R, Moore A, Michaelides M. Inherited cataracts: molecular genetics, clinical features, disease mechanisms and novel therapeutic approaches. Br J Ophthalmol 2020; 104:1331-1337. [PMID: 32217542 DOI: 10.1136/bjophthalmol-2019-315282] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/20/2019] [Accepted: 01/28/2020] [Indexed: 02/01/2023]
Abstract
Cataract is the most common cause of blindness in the world; during infancy and early childhood, it frequently results in visual impairment. Congenital cataracts are phenotypically and genotypically heterogeneous and can occur in isolation or in association with other systemic disorders. Significant progress has been made in identifying the molecular genetic basis of cataract; 115 genes to date have been found to be associated with syndromic and non-syndromic cataract and 38 disease-causing genes have been identified to date to be associated with isolated cataract. In this review, we briefly discuss lens development and cataractogenesis, detail the variable cataract phenotypes and molecular mechanisms, including genotype-phenotype correlations, and explore future novel therapeutic avenues including cellular therapies and pharmacological treatments.
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Affiliation(s)
- Vanita Berry
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK
| | - Michalis Georgiou
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Kaoru Fujinami
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,National Institute of Sensory Organs, National Hospital Organization, Tokyo Medical Centre, Tokyo, Japan
| | - Roy Quinlan
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Department of Biosciences, School of Biological and Medical Sciences, University of Durham, Durham, UK
| | - Anthony Moore
- Moorfields Eye Hospital NHS Foundation Trust, London, UK.,Ophthalmology Department, University of California School of Medicine, San Francisco, California, USA
| | - Michel Michaelides
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK .,Moorfields Eye Hospital NHS Foundation Trust, London, UK
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9
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Failure of Oxysterols Such as Lanosterol to Restore Lens Clarity from Cataracts. Sci Rep 2019; 9:8459. [PMID: 31186457 PMCID: PMC6560215 DOI: 10.1038/s41598-019-44676-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 05/01/2019] [Indexed: 01/13/2023] Open
Abstract
The paradigm that cataracts are irreversible and that vision from cataracts can only be restored through surgery has recently been challenged by reports that oxysterols such as lanosterol and 25-hydroxycholesterol can restore vision by binding to αB-crystallin chaperone protein to dissolve or disaggregate lenticular opacities. To confirm this premise, in vitro rat lens studies along with human lens protein solubilization studies were conducted. Cataracts were induced in viable rat lenses cultured for 48 hours in TC-199 bicarbonate media through physical trauma, 10 mM ouabain as Na+/K+ ATPase ion transport inhibitor, or 1 mM of an experimental compound that induces water influx into the lens. Subsequent 48-hour incubation with 15 mM of lanosterol liposomes failed to either reverse these lens opacities or prevent the further progression of cataracts to the nuclear stage. Similarly, 3-day incubation of 47-year old human lenses in media containing 0.20 mM lanosterol or 60-year-old human lenses in 0.25 and 0.50 mM 25-hydroxycholesterol failed to increase the levels of soluble lens proteins or decrease the levels of insoluble lens proteins. These binding studies were followed up with in silico binding studies of lanosterol, 25-hydroxycholesterol, and ATP as a control to two wild type (2WJ7 and 2KLR) and one R120G mutant (2Y1Z) αB-crystallins using standard MOETM (Molecular Operating Environment) and Schrödinger's Maestro software. Results confirmed that compared to ATP, both oxysterols failed to reach the acceptable threshold binding scores for good predictive binding to the αB-crystallins. In summary, all three studies failed to provide evidence that lanosterol or 25-hydroxycholesterol have either anti-cataractogenic activity or bind aggregated lens protein to dissolve cataracts.
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10
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Zhao Y, Wilmarth PA, Cheng C, Limi S, Fowler VM, Zheng D, David LL, Cvekl A. Proteome-transcriptome analysis and proteome remodeling in mouse lens epithelium and fibers. Exp Eye Res 2019; 179:32-46. [PMID: 30359574 PMCID: PMC6360118 DOI: 10.1016/j.exer.2018.10.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 08/31/2018] [Accepted: 10/20/2018] [Indexed: 12/21/2022]
Abstract
Epithelial cells and differentiated fiber cells represent distinct compartments in the ocular lens. While previous studies have revealed proteins that are preferentially expressed in epithelial vs. fiber cells, a comprehensive proteomics library comparing the molecular compositions of epithelial vs. fiber cells is essential for understanding lens formation, function, disease and regenerative potential, and for efficient differentiation of pluripotent stem cells for modeling of lens development and pathology in vitro. To compare protein compositions between the lens epithelium and fibers, we employed tandem mass spectrometry (2D-LC/MS) analysis of microdissected mouse P0.5 lenses. Functional classifications of the top 525 identified proteins into gene ontology categories by molecular processes and subcellular localizations, were adapted for the lens. Expression levels of both epithelial and fiber proteomes were compared with whole lens proteome and mRNA levels using E14.5, E16.5, E18.5, and P0.5 RNA-Seq data sets. During this developmental time window, multiple complex biosynthetic and catabolic processes generate the molecular and structural foundation for lens transparency. As expected, crystallins showed a high correlation between their mRNA and protein levels. Comprehensive data analysis confirmed and/or predicted roles for transcription factors (TFs), RNA-binding proteins (e.g. Carhsp1), translational apparatus including ribosomal heterogeneity and initiation factors, microtubules, cytoskeletal [e.g. non-muscle myosin IIA heavy chain (Myh9) and βB2-spectrin (Sptbn2)] and membrane proteins in lens formation and maturation. Our data highlighted many proteins with unknown functions in the lens that were preferentially enriched in epithelium or fibers, setting the stage for future studies to further dissect the roles of these proteins in fiber cell differentiation vs. epithelial cell maintenance. In conclusion, the present proteomic datasets represent the first mouse lens epithelium and fiber cell proteomes, establish comparative analyses of protein and RNA-Seq data, and characterize the major proteome remodeling required to form the mature lens fiber cells.
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Affiliation(s)
- Yilin Zhao
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Phillip A Wilmarth
- Department of Biochemistry & Molecular Biology, Oregon Health Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Catherine Cheng
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Saima Limi
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Velia M Fowler
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Deyou Zheng
- Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Neurology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Neuroscience, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Larry L David
- Department of Biochemistry & Molecular Biology, Oregon Health Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Ales Cvekl
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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11
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Metabolism and Biological Activities of 4-Methyl-Sterols. Molecules 2019; 24:molecules24030451. [PMID: 30691248 PMCID: PMC6385002 DOI: 10.3390/molecules24030451] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 01/19/2019] [Accepted: 01/23/2019] [Indexed: 12/12/2022] Open
Abstract
4,4-Dimethylsterols and 4-methylsterols are sterol biosynthetic intermediates (C4-SBIs) acting as precursors of cholesterol, ergosterol, and phytosterols. Their accumulation caused by genetic lesions or biochemical inhibition causes severe cellular and developmental phenotypes in all organisms. Functional evidence supports their role as meiosis activators or as signaling molecules in mammals or plants. Oxygenated C4-SBIs like 4-carboxysterols act in major biological processes like auxin signaling in plants and immune system development in mammals. It is the purpose of this article to point out important milestones and significant advances in the understanding of the biogenesis and biological activities of C4-SBIs.
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12
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Murphy P, Kabir MH, Srivastava T, Mason ME, Dewi CU, Lim S, Yang A, Djordjevic D, Killingsworth MC, Ho JWK, Harman DG, O'Connor MD. Light-focusing human micro-lenses generated from pluripotent stem cells model lens development and drug-induced cataract in vitro. Development 2018; 145:dev.155838. [PMID: 29217756 PMCID: PMC5825866 DOI: 10.1242/dev.155838] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 11/15/2017] [Indexed: 12/14/2022]
Abstract
Cataracts cause vision loss and blindness by impairing the ability of the ocular lens to focus light onto the retina. Various cataract risk factors have been identified, including drug treatments, age, smoking and diabetes. However, the molecular events responsible for these different forms of cataract are ill-defined, and the advent of modern cataract surgery in the 1960s virtually eliminated access to human lenses for research. Here, we demonstrate large-scale production of light-focusing human micro-lenses from spheroidal masses of human lens epithelial cells purified from differentiating pluripotent stem cells. The purified lens cells and micro-lenses display similar morphology, cellular arrangement, mRNA expression and protein expression to human lens cells and lenses. Exposing the micro-lenses to the emergent cystic fibrosis drug Vx-770 reduces micro-lens transparency and focusing ability. These human micro-lenses provide a powerful and large-scale platform for defining molecular disease mechanisms caused by cataract risk factors, for anti-cataract drug screening and for clinically relevant toxicity assays.
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Affiliation(s)
- Patricia Murphy
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Md Humayun Kabir
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia.,Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Tarini Srivastava
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Michele E Mason
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Chitra U Dewi
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Seakcheng Lim
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Andrian Yang
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - Djordje Djordjevic
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - Murray C Killingsworth
- Electron Microscopy Laboratory, NSW Health Pathology and Correlative Microscopy Facility, Ingham Institute, Liverpool, NSW 2170, Australia
| | - Joshua W K Ho
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - David G Harman
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Michael D O'Connor
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia .,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
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13
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Moos WH, Faller DV, Glavas IP, Harpp DN, Irwin MH, Kanara I, Pinkert CA, Powers WR, Steliou K, Vavvas DG, Kodukula K. Epigenetic Treatment of Neurodegenerative Ophthalmic Disorders: An Eye Toward the Future. Biores Open Access 2017; 6:169-181. [PMID: 29291141 PMCID: PMC5747116 DOI: 10.1089/biores.2017.0036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Eye disease is one of the primary medical conditions that requires attention and therapeutic intervention in ageing populations worldwide. Further, the global burden of diabetes and obesity, along with heart disease, all lead to secondary manifestations of ophthalmic distress. Therefore, there is increased interest in developing innovative new approaches that target various mechanisms and sequelae driving conditions that result in adverse vision. The research challenge is even greater given that the terrain of eye diseases is difficult to landscape into a single therapeutic theme. This report addresses the burden of eye disease due to mitochondrial dysfunction, including antioxidant, autophagic, epigenetic, mitophagic, and other cellular processes that modulate the biomedical end result. In this light, we single out lipoic acid as a potent known natural activator of these pathways, along with alternative and potentially more effective conjugates, which together harness the necessary potency, specificity, and biodistribution parameters required for improved therapeutic outcomes.
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Affiliation(s)
- Walter H. Moos
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of California San Francisco, San Francisco, California
- ShangPharma Innovation, Inc., South San Francisco, California
| | - Douglas V. Faller
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
- Cancer Research Center, Boston University School of Medicine, Boston, Massachusetts
| | - Ioannis P. Glavas
- Department of Ophthalmology, New York University School of Medicine, New York, New York
| | - David N. Harpp
- Department of Chemistry, McGill University, Montreal, QC, Canada
| | - Michael H. Irwin
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama
| | | | - Carl A. Pinkert
- Department of Biological Sciences, College of Arts and Sciences, The University of Alabama, Tuscaloosa, Alabama
| | - Whitney R. Powers
- Department of Health Sciences, Boston University, Boston, Massachusetts
- Department of Anatomy, Boston University School of Medicine, Boston, Massachusetts
| | - Kosta Steliou
- Cancer Research Center, Boston University School of Medicine, Boston, Massachusetts
- PhenoMatriX, Inc., Natick, Massachusetts
| | - Demetrios G. Vavvas
- Retina Service, Angiogenesis Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Krishna Kodukula
- ShangPharma Innovation, Inc., South San Francisco, California
- PhenoMatriX, Inc., Natick, Massachusetts
- Bridgewater College, Bridgewater, Virginia
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14
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Coroneo MT. Paradigm shifts, peregrinations and pixies in ophthalmology. Clin Exp Ophthalmol 2017; 46:280-297. [PMID: 28715851 DOI: 10.1111/ceo.13023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 06/28/2017] [Accepted: 07/05/2017] [Indexed: 12/21/2022]
Abstract
Human ingenuity is challenged by defending vision, our highest bandwidth sense. Special challenges are presented by the replacement or repair of highly specialized but scarce tissue within the constraints of transparency, tissue shape and alignment, tissue borders and pressure maintenance. Many, mostly destructive, surgical procedures were developed prior to an understanding of underlying pathophysiology. For a number of conditions, both reconstructive and destructive procedures co-exist, yet there are few guidelines as to the better approach. Because the consequences of these procedures may take many years to surface (consistent with a stem cell role in long-term tissue maintenance), guidance may be provided by the elucidation of underlying principles from these approaches. Illustrative examples from clinical, basic research and biotechnology, particularly relating to pterygium, ocular surface squamous neoplasia, dry-eye syndrome, corneal rehabilitation and replacement, cataract surgery, strabismus surgery and bionic eye research, are described. An unexpected consequence of bionic device development has been an appreciation of the sophistication of tissues being replaced, given the limitations of available biomaterials. Examples of how this has provided insights into ocular disease will be illustrated. Stem cell and biomaterial technologies are starting to impact at a time when cost-effectiveness is under scrutiny. Both efficacy and cost will need to be considered as these interventions are introduced. It appears that the paradigm shift rate is accelerating and there is evidence of this in ophthalmology. Lessons learned from the areas of destructive versus reconstructive surgery and the limitations of development of bionic replacements will be used to illustrate how new procedures and technologies can be developed.
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Affiliation(s)
- Minas T Coroneo
- Department of Ophthalmology, University of New South Wales at Prince of Wales Hospital, Sydney, Australia.,Ophthalmic Surgeons, Sydney, Australia.,East Sydney Private Hospital, Sydney, Australia.,Look for Life Foundation, Sydney, Australia
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15
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Mymrikov EV, Daake M, Richter B, Haslbeck M, Buchner J. The Chaperone Activity and Substrate Spectrum of Human Small Heat Shock Proteins. J Biol Chem 2016; 292:672-684. [PMID: 27909051 DOI: 10.1074/jbc.m116.760413] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 11/12/2016] [Indexed: 11/06/2022] Open
Abstract
Small heat shock proteins (sHsps) are a ubiquitous family of molecular chaperones that suppress the unspecific aggregation of miscellaneous proteins. Multicellular organisms contain a large number of different sHsps, raising questions as to whether they function redundantly or are specialized in terms of substrates and mechanism. To gain insight into this issue, we undertook a comparative analysis of the eight major human sHsps on the aggregation of both model proteins and cytosolic lysates under standardized conditions. We discovered that sHsps, which form large oligomers (HspB1/Hsp27, HspB3, HspB4/αA-crystallin, and HspB5/αB-crystallin) are promiscuous chaperones, whereas the chaperone activity of the other sHsps is more substrate-dependent. However, all human sHsps analyzed except HspB7 suppressed the aggregation of cytosolic proteins of HEK293 cells. We identified ∼1100 heat-sensitive HEK293 proteins, 12% of which could be isolated in complexes with sHsps. Analysis of their biochemical properties revealed that most of the sHsp substrates have a molecular mass from 50 to 100 kDa and a slightly acidic pI (5.4-6.8). The potency of the sHsps to suppress aggregation of model substrates is correlated with their ability to form stable substrate complexes; especially HspB1 and HspB5, but also B3, bind tightly to a variety of proteins, whereas fewer substrates were detected in complex with the other sHsps, although these were also efficient in preventing the aggregation of cytosolic proteins.
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Affiliation(s)
- Evgeny V Mymrikov
- From the Center for Integrated Protein Science at the Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Marina Daake
- From the Center for Integrated Protein Science at the Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Bettina Richter
- From the Center for Integrated Protein Science at the Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Martin Haslbeck
- From the Center for Integrated Protein Science at the Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Johannes Buchner
- From the Center for Integrated Protein Science at the Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
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16
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Ainsbury EA, Barnard S, Bright S, Dalke C, Jarrin M, Kunze S, Tanner R, Dynlacht JR, Quinlan RA, Graw J, Kadhim M, Hamada N. Ionizing radiation induced cataracts: Recent biological and mechanistic developments and perspectives for future research. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2016; 770:238-261. [DOI: 10.1016/j.mrrev.2016.07.010] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/27/2016] [Accepted: 07/28/2016] [Indexed: 02/06/2023]
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17
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Kondo T, Nakamori T, Nagai H, Takeshita A, Kusakabe KT, Okada T. A novel spontaneous mutation of BCAR3 results in extrusion cataracts in CF#1 mouse strain. Mamm Genome 2016; 27:451-9. [PMID: 27364350 DOI: 10.1007/s00335-016-9653-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 06/13/2016] [Indexed: 10/21/2022]
Abstract
A substrain of mice originating from the CF#1 strain (an outbred colony) reared at Osaka Prefecture University (CF#1/lr mice) develops cataracts beginning at 4 weeks of age. Affected mice were fully viable and fertile and developed cataracts by 14 weeks of age. Histologically, CF#1/lr mice showed vacuolation of the lens cortex, swollen lens fibers, lens rupture and nuclear extrusion. To elucidate the mode of inheritance, we analyzed heterozygous mutant hybrids generated from CF#1/lr mice and wild-type BALB/c mice. None of the heterozygous mutants were affected, and the ratio of affected to unaffected mice was 1:3 among the offspring of the heterozygous mutants. For the initial genome-wide screening and further mapping, we used affected progeny of CF#1/lr × (CF#1/lr × BALB/c) mice. We concluded that the cataracts in CF#1/lr mice are inherited through an autosomal recessive mutation and that the mutant gene is located on mouse chromosome 3 between D3Mit79 and D3Mit216. In this region, we identified 8 genes associated with ocular disease. All 8 genes were sequenced and a novel point mutation (1 bp insertion of cytosine) in exon 7 of the Bcar3 gene was identified. This mutation produced a premature stop codon and a truncated protein. In conclusion, we have identified the first spontaneous mutation in the Bcar3 gene associated with lens extrusion cataracts. This novel cataract model may provide further knowledge of the molecular biology of cataractogenesis and the function of the BCAR3 protein.
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Affiliation(s)
- Tomohiro Kondo
- Department of Laboratory Animal Science, Graduate School of Life and Environmental Biosciences, Osaka Prefecture University, 1-58 Rinku Ourai kita, Izumisano, Osaka, 598-8531, Japan.
| | - Taketo Nakamori
- Department of Laboratory Animal Science, Graduate School of Life and Environmental Biosciences, Osaka Prefecture University, 1-58 Rinku Ourai kita, Izumisano, Osaka, 598-8531, Japan
| | - Hiroaki Nagai
- Department of Laboratory Animal Science, Graduate School of Life and Environmental Biosciences, Osaka Prefecture University, 1-58 Rinku Ourai kita, Izumisano, Osaka, 598-8531, Japan
| | - Ai Takeshita
- Department of Laboratory Animal Science, Graduate School of Life and Environmental Biosciences, Osaka Prefecture University, 1-58 Rinku Ourai kita, Izumisano, Osaka, 598-8531, Japan
| | - Ken-Takeshi Kusakabe
- Laboratory of Basic Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, 753-8515, Japan
| | - Toshiya Okada
- Department of Laboratory Animal Science, Graduate School of Life and Environmental Biosciences, Osaka Prefecture University, 1-58 Rinku Ourai kita, Izumisano, Osaka, 598-8531, Japan
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18
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Anand D, Lachke SA. Systems biology of lens development: A paradigm for disease gene discovery in the eye. Exp Eye Res 2016; 156:22-33. [PMID: 26992779 DOI: 10.1016/j.exer.2016.03.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 03/08/2016] [Accepted: 03/11/2016] [Indexed: 12/19/2022]
Abstract
Over the past several decades, the biology of the developing lens has been investigated using molecular genetics-based approaches in various vertebrate model systems. These efforts, involving target gene knockouts or knockdowns, have led to major advances in our understanding of lens morphogenesis and the pathological basis of cataracts, as well as of other lens related eye defects. In particular, we now have a functional understanding of regulators such as Pax6, Six3, Sox2, Oct1 (Pou2f1), Meis1, Pnox1, Zeb2 (Sip1), Mab21l1, Foxe3, Tfap2a (Ap2-alpha), Pitx3, Sox11, Prox1, Sox1, c-Maf, Mafg, Mafk, Hsf4, Fgfrs, Bmp7, and Tdrd7 in this tissue. However, whether these individual regulators interact or their targets overlap, and the significance of such interactions during lens morphogenesis, is not well defined. The arrival of high-throughput approaches for gene expression profiling (microarrays, RNA-sequencing (RNA-seq), etc.), which can be coupled with chromatin immunoprecipitation (ChIP) or RNA immunoprecipitation (RIP) assays, along with improved computational resources and publically available datasets (e.g. those containing comprehensive protein-protein, protein-DNA information), presents new opportunities to advance our understanding of the lens tissue on a global systems level. Such systems-level knowledge will lead to the derivation of the underlying lens gene regulatory network (GRN), defined as a circuit map of the regulator-target interactions functional in lens development, which can be applied to expedite cataract gene discovery. In this review, we cover the various systems-level approaches such as microarrays, RNA-seq, and ChIP that are already being applied to lens studies and discuss strategies for assembling and interpreting these vast amounts of high-throughput information for effective dispersion to the scientific community. In particular, we discuss strategies for effective interpretation of this new information in the context of the rich knowledge obtained through the application of traditional single-gene focused experiments on the lens. Finally, we discuss our vision for integrating these diverse high-throughput datasets in a single web-based user-friendly tool iSyTE (integrated Systems Tool for Eye gene discovery) - a resource that is already proving effective in the identification and characterization of genes linked to lens development and cataract. We anticipate that application of a similar approach to other ocular tissues such as the retina and the cornea, and even other organ systems, will significantly impact disease gene discovery.
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Affiliation(s)
- Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE, USA; Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, USA.
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