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1.
Front Genet ; 14: 1113058, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37351342

RESUMO

Introduction: Long axial length (AL) is a risk factor for myopia. Although family studies indicate that AL has an important genetic component with heritability estimates up to 0.94, there have been few reports of AL-associated loci. Methods: Here, we conducted a multiethnic genome-wide association study (GWAS) of AL in 19,420 adults of European, Latino, Asian, and African ancestry from the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort, with replication in a subset of the Consortium for Refractive Error and Myopia (CREAM) cohorts of European or Asian ancestry. We further examined the effect of the identified loci on the mean spherical equivalent (MSE) within the GERA cohort. We also performed genome-wide genetic correlation analyses to quantify the genetic overlap between AL and MSE or myopia risk in the GERA European ancestry sample. Results: Our multiethnic GWA analysis of AL identified a total of 16 genomic loci, of which 5 are novel. We found that all AL-associated loci were significantly associated with MSE after Bonferroni correction. We also found that AL was genetically correlated with MSE (rg = -0.83; SE, 0.04; p = 1.95 × 10-89) and myopia (rg = 0.80; SE, 0.05; p = 2.84 × 10-55). Finally, we estimated the array heritability for AL in the GERA European ancestry sample using LD score regression, and found an overall heritability estimate of 0.37 (s.e. = 0.04). Discussion: In this large and multiethnic study, we identified novel loci, associated with AL at a genome-wide significance level, increasing substantially our understanding of the etiology of AL variation. Our results also demonstrate an association between AL-associated loci and MSE and a shared genetic basis between AL and myopia risk.

2.
Nat Commun ; 12(1): 4877, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385434

RESUMO

Chronically elevated intraocular pressure (IOP) is the major risk factor of primary open-angle glaucoma, a leading cause of blindness. Dysfunction of the trabecular meshwork (TM), which controls the outflow of aqueous humor (AqH) from the anterior chamber, is the major cause of elevated IOP. Here, we demonstrate that mice deficient in the Krüppel-like zinc finger transcriptional factor GLI-similar-1 (GLIS1) develop chronically elevated IOP. Magnetic resonance imaging and histopathological analysis reveal that deficiency in GLIS1 expression induces progressive degeneration of the TM, leading to inefficient AqH drainage from the anterior chamber and elevated IOP. Transcriptome and cistrome analyses identified several glaucoma- and extracellular matrix-associated genes as direct transcriptional targets of GLIS1. We also identified a significant association between GLIS1 variant rs941125 and glaucoma in humans (P = 4.73 × 10-6), further supporting a role for GLIS1 into glaucoma etiology. Our study identifies GLIS1 as a critical regulator of TM function and maintenance, AqH dynamics, and IOP.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Pressão Intraocular/fisiologia , Malha Trabecular/fisiopatologia , Fatores de Transcrição/metabolismo , Animais , Humor Aquoso/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação/métodos , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Glaucoma/genética , Glaucoma/metabolismo , Células HEK293 , Humanos , Pressão Intraocular/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA-Seq/métodos , Malha Trabecular/metabolismo , Fatores de Transcrição/genética
3.
Nat Commun ; 12(1): 3595, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127677

RESUMO

Cataract is the leading cause of blindness among the elderly worldwide and cataract surgery is one of the most common operations performed in the United States. As the genetic etiology of cataract formation remains unclear, we conducted a multiethnic genome-wide association meta-analysis, combining results from the GERA and UK Biobank cohorts, and tested for replication in the 23andMe research cohort. We report 54 genome-wide significant loci, 37 of which were novel. Sex-stratified analyses identified CASP7 as an additional novel locus specific to women. We show that genes within or near 80% of the cataract-associated loci are significantly expressed and/or enriched-expressed in the mouse lens across various spatiotemporal stages as per iSyTE analysis. Furthermore, iSyTE shows 32 candidate genes in the associated loci have altered gene expression in 9 different gene perturbation mouse models of lens defects/cataract, suggesting their relevance to lens biology. Our work provides further insight into the complex genetic architecture of cataract susceptibility.


Assuntos
Catarata/genética , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Envelhecimento , Animais , Caspase 7/genética , Estudos de Coortes , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Cristalino , Modelos Logísticos , Camundongos , Camundongos Knockout , Epidemiologia Molecular , Ribonucleoproteínas/genética , Fatores Sexuais
4.
PLoS Genet ; 17(3): e1009458, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33755662

RESUMO

Precise regulation of ocular size is a critical determinant of normal visual acuity. Although it is generally accepted that ocular growth relies on a cascade of signaling events transmitted from the retina to the sclera, the factors and mechanism(s) involved are poorly understood. Recent studies have highlighted the importance of the retinal secreted serine protease PRSS56 and transmembrane glycoprotein MFRP, a factor predominantly expressed in the retinal pigment epithelium (RPE), in ocular size determination. Mutations in PRSS56 and MFRP constitute a major cause of nanophthalmos, a condition characterized by severe reduction in ocular axial length/extreme hyperopia. Interestingly, common variants of these genes have been implicated in myopia, a condition associated with ocular elongation. Consistent with these findings, mice with loss of function mutation in PRSS56 or MFRP exhibit a reduction in ocular axial length. However, the molecular network and cellular processes involved in PRSS56- and MFRP-mediated ocular axial growth remain elusive. Here, we show that Adamts19 expression is significantly upregulated in the retina of mice lacking either Prss56 or Mfrp. Importantly, using genetic mouse models, we demonstrate that while ADAMTS19 is not required for ocular growth during normal development, its inactivation exacerbates ocular axial length reduction in Prss56 and Mfrp mutant mice. These results suggest that the upregulation of retinal Adamts19 is part of an adaptive molecular response to counteract impaired ocular growth. Using a complementary genetic approach, we show that loss of PRSS56 or MFRP function prevents excessive ocular axial growth in a mouse model of early-onset myopia caused by a null mutation in Irbp, thus, demonstrating that PRSS56 and MFRP are also required for pathological ocular elongation. Collectively, our findings provide new insights into the molecular network involved in ocular axial growth and support a role for molecular crosstalk between the retina and RPE involved in refractive development.


Assuntos
Proteínas ADAMTS/genética , Proteínas do Olho/genética , Olho/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Proteínas de Membrana/genética , Organogênese/genética , Serina Proteases/genética , Proteínas ADAMTS/metabolismo , Animais , Biomarcadores , Olho/embriologia , Olho/crescimento & desenvolvimento , Proteínas do Olho/metabolismo , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mutação , Proteínas de Ligação ao Retinol/genética , Serina Proteases/metabolismo , Transdução de Sinais
5.
Nat Commun ; 12(1): 1258, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627673

RESUMO

Primary open-angle glaucoma (POAG), is a heritable common cause of blindness world-wide. To identify risk loci, we conduct a large multi-ethnic meta-analysis of genome-wide association studies on a total of 34,179 cases and 349,321 controls, identifying 44 previously unreported risk loci and confirming 83 loci that were previously known. The majority of loci have broadly consistent effects across European, Asian and African ancestries. Cross-ancestry data improve fine-mapping of causal variants for several loci. Integration of multiple lines of genetic evidence support the functional relevance of the identified POAG risk loci and highlight potential contributions of several genes to POAG pathogenesis, including SVEP1, RERE, VCAM1, ZNF638, CLIC5, SLC2A12, YAP1, MXRA5, and SMAD6. Several drug compounds targeting POAG risk genes may be potential glaucoma therapeutic candidates.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Glaucoma de Ângulo Aberto/genética , Povo Asiático , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , População Branca
6.
Dis Model Mech ; 14(2)2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33462143

RESUMO

Variants in the LIM homeobox transcription factor 1-beta (LMX1B) gene predispose individuals to elevated intraocular pressure (IOP), a key risk factor for glaucoma. However, the effect of LMX1B mutations varies widely between individuals. To better understand the mechanisms underlying LMX1B-related phenotypes and individual differences, we backcrossed the Lmx1bV265D (also known as Lmx1bIcst ) allele onto the C57BL/6J (B6), 129/Sj (129), C3A/BLiA-Pde6b+ /J (C3H) and DBA/2J-Gpnmb+ (D2-G) mouse strain backgrounds. Strain background had a significant effect on the onset and severity of ocular phenotypes in Lmx1bV265D/+ mutant mice. Mice of the B6 background were the most susceptible to developing abnormal IOP distribution, severe anterior segment developmental anomalies (including malformed eccentric pupils, iridocorneal strands and corneal abnormalities) and glaucomatous nerve damage. By contrast, Lmx1bV265D mice of the 129 background were the most resistant to developing anterior segment abnormalities, had less severe IOP elevation than B6 mutants at young ages and showed no detectable nerve damage. To identify genetic modifiers of susceptibility to Lmx1bV265D -induced glaucoma-associated phenotypes, we performed a mapping cross between mice of the B6 (susceptible) and 129 (resistant) backgrounds. We identified a modifier locus on Chromosome 18, with the 129 allele(s) substantially lessening severity of ocular phenotypes, as confirmed by congenic analysis. By demonstrating a clear effect of genetic background in modulating Lmx1b-induced phenotypes, providing a panel of strains with different phenotypic severities and identifying a modifier locus, this study lays a foundation for better understanding the roles of LMX1B in glaucoma with the goal of developing new treatments.


Assuntos
Segmento Anterior do Olho/fisiopatologia , Anormalidades do Olho/genética , Predisposição Genética para Doença , Glaucoma/genética , Proteínas com Homeodomínio LIM/genética , Fatores de Transcrição/genética , Alelos , Animais , Cruzamentos Genéticos , Modelos Animais de Doenças , Feminino , Genes Homeobox , Patrimônio Genético , Genótipo , Pressão Intraocular , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Nervo Óptico/patologia , Fenótipo , Especificidade da Espécie
7.
Commun Biol ; 3(1): 301, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32528159

RESUMO

Central corneal thickness (CCT) is one of the most heritable human traits, with broad-sense heritability estimates ranging between 0.68 to 0.95. Despite the high heritability and numerous previous association studies, only 8.5% of CCT variance is currently explained. Here, we report the results of a multiethnic meta-analysis of available genome-wide association studies in which we find association between CCT and 98 genomic loci, of which 41 are novel. Among these loci, 20 were significantly associated with keratoconus, and one (RAPSN rs3740685) was significantly associated with glaucoma after Bonferroni correction. Two-sample Mendelian randomization analysis suggests that thinner CCT does not causally increase the risk of primary open-angle glaucoma. This large CCT study explains up to 14.2% of CCT variance and increases substantially our understanding of the etiology of CCT variation. This may open new avenues of investigation into human ocular traits and their relationship to the risk of vision disorders.


Assuntos
Córnea/patologia , Doenças da Córnea/patologia , Etnicidade/genética , Loci Gênicos , Glaucoma/patologia , Polimorfismo de Nucleotídeo Único , Idoso , Estudos de Coortes , Doenças da Córnea/etnologia , Doenças da Córnea/genética , Feminino , Estudo de Associação Genômica Ampla , Glaucoma/etnologia , Glaucoma/genética , Humanos , Masculino , Análise da Randomização Mendeliana , Metanálise como Assunto , Pessoa de Meia-Idade , Prognóstico
8.
Dis Model Mech ; 13(5)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32152063

RESUMO

Glaucoma is a leading cause of blindness, affecting up to 70 million people worldwide. High intraocular pressure (IOP) is a major risk factor for glaucoma. It is well established that inefficient aqueous humor (AqH) outflow resulting from structural or functional alterations in ocular drainage tissues causes high IOP, but the genes and pathways involved are poorly understood. We previously demonstrated that mutations in the gene encoding the serine protease PRSS56 induces ocular angle closure and high IOP in mice and identified reduced ocular axial length as a potential contributing factor. Here, we show that Prss56-/- mice also exhibit an abnormal iridocorneal angle configuration characterized by a posterior shift of ocular drainage structures relative to the ciliary body and iris. Notably, we show that retina-derived PRSS56 is required between postnatal days 13 and 18 for proper iridocorneal configuration and that abnormal positioning of the ocular drainage tissues is not dependent on ocular size reduction in Prss56-/- mice. Furthermore, we demonstrate that the genetic context modulates the severity of IOP elevation in Prss56 mutant mice and describe a progressive degeneration of ocular drainage tissues that likely contributes to the exacerbation of the high IOP phenotype observed on the C3H/HeJ genetic background. Finally, we identify five rare PRSS56 variants associated with human primary congenital glaucoma, a condition characterized by abnormal development of the ocular drainage structures. Collectively, our findings point to a role for PRSS56 in the development and maintenance of ocular drainage tissues and IOP homeostasis, and provide new insights into glaucoma pathogenesis.


Assuntos
Suscetibilidade a Doenças , Olho/patologia , Olho/fisiopatologia , Pressão Intraocular , Serina Proteases/deficiência , Sequência de Aminoácidos , Animais , Córnea/patologia , Feminino , Glaucoma/genética , Glaucoma/patologia , Iris/patologia , Masculino , Camundongos Knockout , Camundongos Mutantes , Tamanho do Órgão , Serina Proteases/química , Serina Proteases/genética , Serina Proteases/metabolismo
9.
Nat Commun ; 9(1): 2278, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29891935

RESUMO

Primary open-angle glaucoma (POAG) is a leading cause of irreversible vision loss, yet much of the genetic risk remains unaccounted for, especially in African-Americans who have a higher risk for developing POAG. We conduct a multiethnic genome-wide association study (GWAS) of POAG in the GERA cohort, with replication in the UK Biobank (UKB), and vice versa, GWAS in UKB with replication in GERA. We identify 24 loci (P < 5.0 × 10-8), including 14 novel, of which 9 replicate (near FMNL2, PDE7B, TMTC2, IKZF2, CADM2, DGKG, ANKH, EXOC2, and LMX1B). Functional studies support intraocular pressure-related influences of FMNL2 and LMX1B, with certain Lmx1b mutations causing high IOP and glaucoma resembling POAG in mice. The newly identified loci increase the proportion of variance explained in each GERA race/ethnicity group, with the largest gain in African-Americans (0.5-3.1%). A meta-analysis combining GERA and UKB identifies 24 additional loci. Our study provides important insights into glaucoma pathogenesis.


Assuntos
Glaucoma de Ângulo Aberto/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Coortes , Etnicidade/genética , Feminino , Forminas , Expressão Gênica , Técnicas de Silenciamento de Genes , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Pressão Intraocular/genética , Proteínas com Homeodomínio LIM/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Células Ganglionares da Retina/metabolismo , Fatores de Risco , Fatores de Transcrição/genética , Reino Unido
10.
PLoS Genet ; 14(3): e1007244, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29529029

RESUMO

A mismatch between optical power and ocular axial length results in refractive errors. Uncorrected refractive errors constitute the most common cause of vision loss and second leading cause of blindness worldwide. Although the retina is known to play a critical role in regulating ocular growth and refractive development, the precise factors and mechanisms involved are poorly defined. We have previously identified a role for the secreted serine protease PRSS56 in ocular size determination and PRSS56 variants have been implicated in the etiology of both hyperopia and myopia, highlighting its importance in refractive development. Here, we use a combination of genetic mouse models to demonstrate that Prss56 mutations leading to reduced ocular size and hyperopia act via a loss of function mechanism. Using a conditional gene targeting strategy, we show that PRSS56 derived from Müller glia contributes to ocular growth, implicating a new retinal cell type in ocular size determination. Importantly, we demonstrate that persistent activity of PRSS56 is required during distinct developmental stages spanning the pre- and post-eye opening periods to ensure optimal ocular growth. Thus, our mouse data provide evidence for the existence of a molecule contributing to both the prenatal and postnatal stages of human ocular growth. Finally, we demonstrate that genetic inactivation of Prss56 rescues axial elongation in a mouse model of myopia caused by a null mutation in Egr1. Overall, our findings identify PRSS56 as a potential therapeutic target for modulating ocular growth aimed at preventing or slowing down myopia, which is reaching epidemic proportions.


Assuntos
Olho/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Erros de Refração/genética , Serina Proteases/metabolismo , Animais , Modelos Animais de Doenças , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Olho/citologia , Olho/embriologia , Feminino , Humanos , Hiperopia/genética , Masculino , Camundongos Mutantes , Camundongos Transgênicos , Miopia/genética , Miopia/patologia , Neuroglia/metabolismo , Refração Ocular/genética , Refração Ocular/fisiologia , Erros de Refração/prevenção & controle , Serina Proteases/genética
11.
Nat Commun ; 8(1): 2108, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29235454

RESUMO

Elevated intraocular pressure (IOP) is a major risk factor for glaucoma, a leading cause of blindness. IOP heritability has been estimated to up to 67%, and to date only 11 IOP loci have been reported, accounting for 1.5% of IOP variability. Here, we conduct a genome-wide association study of IOP in 69,756 untreated individuals of European, Latino, Asian, and African ancestry. Multiple longitudinal IOP measurements were collected through electronic health records and, in total, 356,987 measurements were included. We identify 47 genome-wide significant IOP-associated loci (P < 5 × 10-8); of the 40 novel loci, 14 replicate at Bonferroni significance in an external genome-wide association study analysis of 37,930 individuals of European and Asian descent. We further examine their effect on the risk of glaucoma within our discovery sample. Using longitudinal IOP measurements from electronic health records improves our power to identify new variants, which together explain 3.7% of IOP variation.


Assuntos
Loci Gênicos/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Glaucoma/genética , Pressão Intraocular/genética , Negro ou Afro-Americano/genética , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Feminino , Predisposição Genética para Doença/etnologia , Glaucoma/etnologia , Glaucoma/fisiopatologia , Hispânico ou Latino/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , População Branca/genética
12.
Dis Model Mech ; 9(8): 863-71, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27483353

RESUMO

A variety of inherited animal models with different genetic causes and distinct genetic backgrounds are needed to help dissect the complex genetic etiology of glaucoma. The scarcity of such animal models has hampered progress in glaucoma research. Here, we introduce a new inherited glaucoma model: the inbred mouse strain YBR/EiJ (YBR). YBR mice develop a form of pigmentary glaucoma. They exhibit a progressive age-related pigment-dispersing iris disease characterized by iris stromal atrophy. Subsequently, these mice develop elevated intraocular pressure (IOP) and glaucoma. Genetic mapping studies utilizing YBR as a glaucoma-susceptible strain and C57BL/6J as a glaucoma-resistant strain were performed to identify genetic loci responsible for the iris disease and high IOP. A recessive locus linked to Tyrp1(b) on chromosome 4 contributes to iris stromal atrophy and high IOP. However, this is not the only important locus. A recessive locus on YBR chromosome 17 causes high IOP independent of the iris stromal atrophy. In specific eyes with high IOP caused by YBR chromosome 17, the drainage angle (through which ocular fluid leaves the eye) is largely open. The YBR alleles of genes on chromosomes 4 and 17 underlie the development of high IOP and glaucoma but do so through independent mechanisms. Together, these two loci act in an additive manner to increase the susceptibility of YBR mice to the development of high IOP. The chromosome 17 locus is important not only because it causes IOP elevation in mice with largely open drainage angles but also because it exacerbates IOP elevation and glaucoma induced by pigment dispersion. Therefore, YBR mice are a valuable resource for studying the genetic etiology of IOP elevation and glaucoma, as well as for testing new treatments.


Assuntos
Cromossomos de Mamíferos/genética , Predisposição Genética para Doença , Glaucoma/genética , Glaucoma/patologia , Animais , Atrofia , Substância Própria/patologia , Modelos Animais de Doenças , Glaucoma/fisiopatologia , Pressão Intraocular , Doenças da Íris/genética , Doenças da Íris/patologia , Camundongos Endogâmicos C57BL , Degeneração Neural/patologia , Pigmentação , Locos de Características Quantitativas
13.
Exp Eye Res ; 141: 42-56, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26116903

RESUMO

While all forms of glaucoma are characterized by a specific pattern of retinal ganglion cell death, they are clinically divided into several distinct subclasses, including normal tension glaucoma, primary open angle glaucoma, congenital glaucoma, and secondary glaucoma. For each type of glaucoma there are likely numerous molecular pathways that control susceptibility to the disease. Given this complexity, a single animal model will never precisely model all aspects of all the different types of human glaucoma. Therefore, multiple animal models have been utilized to study glaucoma but more are needed. Because of the powerful genetic tools available to use in the laboratory mouse, it has proven to be a highly useful mammalian system for studying the pathophysiology of human disease. The similarity between human and mouse eyes coupled with the ability to use a combination of advanced cell biological and genetic tools in mice have led to a large increase in the number of studies using mice to model specific glaucoma phenotypes. Over the last decade, numerous new mouse models and genetic tools have emerged, providing important insight into the cell biology and genetics of glaucoma. In this review, we describe available mouse genetic models that can be used to study glaucoma-relevant disease/pathobiology. Furthermore, we discuss how these models have been used to gain insights into ocular hypertension (a major risk factor for glaucoma) and glaucomatous retinal ganglion cell death. Finally, the potential for developing new mouse models and using advanced genetic tools and resources for studying glaucoma are discussed.


Assuntos
Glaucoma/genética , Pressão Intraocular , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia
14.
BMC Genet ; 15: 42, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24678736

RESUMO

BACKGROUND: The molecular mechanisms causing pigment dispersion syndrome (PDS) and the pathway(s) by which it progresses to pigmentary glaucoma are not known. Mutations in two melanosomal protein genes (Tyrp1(b) and Gpnmb(R150X)) are responsible for pigment dispersing iris disease, which progresses to intraocular pressure (IOP) elevation and subsequent glaucoma in DBA/2J mice. Melanosomal defects along with ocular immune abnormalities play a role in the propagation of pigment dispersion and progression to IOP elevation. Here, we tested the role of specific immune components in the progression of the iris disease and high IOP. RESULTS: We tested the role of NK cells in disease etiology by genetically modifying the B6.D2-Gpnmb(R150X) Tyrp1(b) strain, which develops the same iris disease as DBA/2J mice. Our findings demonstrate that neither diminishing NK mediated cytotoxic activity (Prf1 mutation) nor NK cell depletion (Il2rg mutation) has any influence on the severity or timing of Gpnmb(R150X) Tyrp1(b) mediated iris disease. Since DBA/2J mice are deficient in CD94, an important immune modulator that often acts as an immune suppressor, we generated DBA/2J mice sufficient in CD94. Sufficiency of CD94 failed to alter either the iris disease or the subsequent IOP elevation. Additionally CD94 status had no detected effect on glaucomatous optic nerve damage. CONCLUSION: Our previous data implicate immune components in the manifestation of pigment dispersion and/or IOP elevation in DBA/2J mice. The current study eliminates important immune components, specifically NK cells and CD94 deficiency, as critical in the progression of iris disease and glaucoma. This narrows the field of possible immune components responsible for disease progression.


Assuntos
Glaucoma de Ângulo Aberto/genética , Glaucoma de Ângulo Aberto/imunologia , Doenças da Íris/imunologia , Células Matadoras Naturais/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Feminino , Pressão Intraocular , Doenças da Íris/genética , Masculino , Camundongos Congênicos , Camundongos Endogâmicos DBA , Subfamília D de Receptores Semelhantes a Lectina de Células NK/genética , Nervo Óptico/patologia
15.
PLoS Genet ; 10(3): e1004089, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24603532

RESUMO

Anterior chamber depth (ACD) is a key anatomical risk factor for primary angle closure glaucoma (PACG). We conducted a genome-wide association study (GWAS) on ACD to discover novel genes for PACG on a total of 5,308 population-based individuals of Asian descent. Genome-wide significant association was observed at a sequence variant within ABCC5 (rs1401999; per-allele effect size =  -0.045 mm, P = 8.17 × 10(-9)). This locus was associated with an increase in risk of PACG in a separate case-control study of 4,276 PACG cases and 18,801 controls (per-allele OR = 1.13 [95% CI: 1.06-1.22], P = 0.00046). The association was strengthened when a sub-group of controls with open angles were included in the analysis (per-allele OR = 1.30, P = 7.45 × 10(-9); 3,458 cases vs. 3,831 controls). Our findings suggest that the increase in PACG risk could in part be mediated by genetic sequence variants influencing anterior chamber dimensions.


Assuntos
Câmara Anterior/patologia , Estudo de Associação Genômica Ampla , Glaucoma de Ângulo Fechado/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Câmara Anterior/metabolismo , Povo Asiático , Glaucoma de Ângulo Fechado/patologia , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
16.
Nat Genet ; 43(6): 579-84, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21532570

RESUMO

Angle-closure glaucoma (ACG) is a subset of glaucoma affecting 16 million people. Although 4 million people are bilaterally blind from ACG, the causative molecular mechanisms of ACG remain to be defined. High intraocular pressure induces glaucoma in ACG. High intraocular pressure traditionally was suggested to result from the iris blocking or closing the angle of the eye, thereby limiting aqueous humor drainage. Eyes from individuals with ACG often have a modestly decreased axial length, shallow anterior chamber and relatively large lens, features that predispose to angle closure. Here we show that genetic alteration of a previously unidentified serine protease (PRSS56) alters axial length and causes a mouse phenotype resembling ACG. Mutations affecting this protease also cause a severe decrease of axial length in individuals with posterior microphthalmia. Together, these data suggest that alterations of this serine protease may contribute to a spectrum of human ocular conditions including reduced ocular size and ACG.


Assuntos
Glaucoma de Ângulo Fechado/genética , Microftalmia/genética , Serina Proteases/genética , Animais , Câmara Anterior/anormalidades , Modelos Animais de Doenças , Anormalidades do Olho/genética , Ligação Genética , Humanos , Cristalino/anormalidades , Camundongos , Mutação , Linhagem , Retina/metabolismo , Serina Proteases/metabolismo
17.
Science ; 331(6024): 1571-6, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21436445

RESUMO

The precise transcriptional regulation of gene expression is essential for vertebrate development, but the role of posttranscriptional regulatory mechanisms is less clear. Cytoplasmic RNA granules (RGs) function in the posttranscriptional control of gene expression, but the extent of RG involvement in organogenesis is unknown. We describe two human cases of pediatric cataract with loss-of-function mutations in TDRD7 and demonstrate that Tdrd7 nullizygosity in mouse causes cataracts, as well as glaucoma and an arrest in spermatogenesis. TDRD7 is a Tudor domain RNA binding protein that is expressed in lens fiber cells in distinct TDRD7-RGs that interact with STAU1-ribonucleoproteins (RNPs). TDRD7 coimmunoprecipitates with specific lens messenger RNAs (mRNAs) and is required for the posttranscriptional control of mRNAs that are critical to normal lens development and to RG function. These findings demonstrate a role for RGs in vertebrate organogenesis.


Assuntos
Catarata/genética , Regulação da Expressão Gênica no Desenvolvimento , Glaucoma/genética , Cristalino/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribonucleoproteínas/metabolismo , Animais , Catarata/congênito , Catarata/patologia , Linhagem Celular , Embrião de Galinha , Cristalinas/genética , Cristalinas/metabolismo , Grânulos Citoplasmáticos/metabolismo , Desenvolvimento Embrionário , Feminino , Técnicas de Silenciamento de Genes , Humanos , Hipospadia/genética , Cristalino/embriologia , Masculino , Camundongos , Mutação , Organogênese , Biossíntese de Proteínas , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/genética , Espermatogênese/genética
18.
Biochem J ; 417(3): 803-12, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18840097

RESUMO

Vertebrate phototransduction is mediated by cGMP, which is generated by retGC (retinal guanylate cyclase) and degraded by cGMP phosphodiesterase. Light stimulates cGMP hydrolysis via the G-protein transducin, which directly binds to and activates phosphodiesterase. Bright light also causes relocalization of transducin from the OS (outer segments) of the rod cells to the inner compartments. In the present study, we show experimental evidence for a previously unknown interaction between G(alphat) (the transducin alpha subunit) and retGC. G(alphat) co-immunoprecipitates with retGC from the retina or from co-transfected COS-7 cells. The retGC-G(alphat) complex is also present in cones. The interaction also occurs in mice lacking RGS9 (regulator of G-protein signalling 9), a protein previously shown to associate with both G(alphat) and retGC. The G(alphat)-retGC interaction is mediated primarily by the kinase homology domain of retGC, which binds GDP-bound G(alphat) stronger than the GTP[S] (GTPgammaS; guanosine 5'-[gamma-thio]triphosphate) form. Neither G(alphat) nor G(betagamma) affect retGC-mediated cGMP synthesis, regardless of the presence of GCAP (guanylate cyclase activating protein) and Ca2+. The rate of light-dependent transducin redistribution from the OS to the inner segments is markedly accelerated in the retGC-1-knockout mice, while the migration of transducin to the OS after the onset of darkness is delayed. Supplementation of permeabilized photoreceptors with cGMP does not affect transducin translocation. Taken together, these results suggest that the protein-protein interaction between G(alphat) and retGC represents a novel mechanism regulating light-dependent translocation of transducin in rod photoreceptors.


Assuntos
Guanilato Ciclase/metabolismo , Subunidades Proteicas/análise , Subunidades Proteicas/metabolismo , Retina/enzimologia , Transducina/análise , Transducina/metabolismo , Animais , Células COS , Bovinos , Células Cultivadas , Chlorocebus aethiops , Guanilato Ciclase/genética , Humanos , Imunoprecipitação , Camundongos , Camundongos Knockout , Retina/metabolismo , Transfecção
19.
BMC Genet ; 9: 30, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-18402690

RESUMO

BACKGROUND: The Gpnmb gene encodes a transmembrane protein whose function(s) remain largely unknown. Here, we assess if a mutant allele of Gpnmb confers susceptibility to glaucoma by altering immune functions. DBA/2J mice have a mutant Gpnmb gene and they develop a form of glaucoma preceded by a pigment dispersing iris disease and abnormalities of the immunosuppressive ocular microenvironment. RESULTS: We find that the Gpnmb genotype of bone-marrow derived cell lineages significantly influences the iris disease and the elevation of intraocular pressure. GPNMB localizes to multiple cell types, including pigment producing cells, bone marrow derived F4/80 positive antigen-presenting cells (APCs) of the iris and dendritic cells. We show that APCs of DBA/2J mice fail to induce antigen induced immune deviation (a form of tolerance) when treated with TGFbeta2. This demonstrates that some of the immune abnormalities previously identified in DBA/2J mice result from intrinsic defects in APCs. However, the tested APC defects are not dependent on a mutant Gpnmb gene. Finally, we show that the Gpnmb mediated iris disease does not require elevated IL18 or mature B or T lymphocytes. CONCLUSION: These results establish a role for Gpnmb in bone marrow derived lineages. They suggest that affects of Gpnmb on innate immunity influence susceptibility to glaucoma in DBA/2J mice.


Assuntos
Células da Medula Óssea/fisiologia , Proteínas do Olho/genética , Glaucoma/genética , Glicoproteínas de Membrana/genética , Mutação , Alelos , Animais , Células Apresentadoras de Antígenos/imunologia , Humor Aquoso/imunologia , Células da Medula Óssea/imunologia , Suscetibilidade a Doenças , Genótipo , Glaucoma/imunologia , Glaucoma/fisiopatologia , Interleucina-18/imunologia , Pressão Intraocular/genética , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA
20.
J Neurosci ; 27(20): 5484-94, 2007 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-17507570

RESUMO

Activation of rod photoreceptors by light induces a massive redistribution of the heterotrimeric G-protein transducin. In darkness, transducin is sequestered within the membrane-enriched outer segments of the rod cell. In light, it disperses throughout the entire neuron. We show here that redistribution of rod transducin by light requires activation, but it does not require ATP. This observation rules out participation of molecular motors in the redistribution process. In contrast to the light-stimulated redistribution of rod transducin in rods, cone transducin in cones does not redistribute during activation. Remarkably, when cone transducin is expressed in rods, it does undergo light-stimulated redistribution. We show here that the difference in subcellular localization of activated rod and cone G-proteins correlates with their affinity for membranes. Activated rod transducin releases from membranes, whereas activated cone transducin remains bound to membranes. A synthetic peptide that dissociates G-protein complexes independently of activation facilitates dispersion of both rod and cone transducins within the cells. This peptide also facilitates detachment of both G-proteins from the membranes. Together, these results show that it is the dissociation state of transducin that determines its localization in photoreceptors. When rod transducin is stimulated, its subunits dissociate, leave outer segment membranes, and equilibrate throughout the cell. Cone transducin subunits do not dissociate during activation and remain sequestered within the outer segment. These findings indicate that the subunits of some heterotrimeric G-proteins remain associated during activation in their native environments.


Assuntos
Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/citologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Transducina/biossíntese , Animais , Proteínas de Ligação ao GTP/análise , Proteínas de Ligação ao GTP/biossíntese , Proteínas de Ligação ao GTP/genética , Camundongos , Estimulação Luminosa/métodos , Células Fotorreceptoras Retinianas Cones/química , Células Fotorreceptoras Retinianas Bastonetes/química , Transducina/análise , Transducina/genética , Visão Ocular/fisiologia
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