Crumbs homologue 1 in polarity and blindness

2004 ◽  
Vol 32 (5) ◽  
pp. 828-830 ◽  
Author(s):  
J. Meuleman ◽  
S.A. van de Pavert ◽  
J. Wijnholds
Keyword(s):  
Retinitis Pigmentosa ◽  
Retinal Degeneration ◽  
Cell Polarity ◽  
Current Knowledge ◽  
Leber Congenital Amaurosis ◽  
Retinal Dystrophies

Several retinal dystrophies, including retinitis pigmentosa type 12 and Leber congenital amaurosis, are caused by a large variety of mutations in the CRB1 (Crumbs homologue 1) gene. This discovery led to an increased focus on the function of CRB1 and the Drosophila homologue Crumbs. In the present study, we review the current knowledge on Crumbs and its vertebrate homologues, their function in cell polarity and their pathogenicity in retinal degeneration.

scholarly journals Ciliary Genes arl13b, ahi1 and cc2d2a Differentially Modify Expression of Visual Acuity Phenotypes but do not Enhance Retinal Degeneration due to Mutation of cep290 in Zebrafish

2019 ◽  
Author(s):  
Emma M. Lessieur ◽  
Ping Song ◽  
Gabrielle C. Nivar ◽  
Ellen M. Piccillo ◽  
Joseph Fogerty ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Retinal Degeneration ◽  
Joubert Syndrome ◽  
Genetic Modifiers ◽  
Photoreceptor Degeneration ◽  
Optokinetic Response ◽  
Bardet Biedl Syndrome ◽  
Leber Congenital Amaurosis ◽  
Outer Segments ◽  
Rhodopsin Kinase

ABSTRACTMutations in the gene Centrosomal Protein 290 kDa (CEP290) result in multiple ciliopathies ranging from the neonatal lethal disorder Meckel-Gruber Syndrome to multi-systemic disorders such as Joubert Syndrome and Bardet-Biedl Syndrome to nonsyndromic diseases like Leber Congenital Amaurosis (LCA) and retinitis pigmentosa. Results from model organisms and human genetics studies, have suggest that mutations in genes encoding protein components of the transition zone (TZ) and other cilia-associated proteins can function as genetic modifiers and be a source for CEP290 pleiotropy. We investigated the zebrafish cep290fh297/fh297 mutant, which encodes a nonsense mutation (p.Q1217*). This mutant is viable as adults, exhibits scoliosis, and undergoes a slow, progressive cone degeneration. The cep290fh297/fh297 mutants showed partial mislocalization of the transmembrane protein rhodopsin but not of the prenylated proteins rhodopsin kinase (GRK1) or the rod transducin subunit GNB1. Surprisingly, photoreceptor degeneration did not trigger proliferation of Müller glia, but proliferation of rod progenitors in the outer nuclear layer was significantly increased. To determine if heterozygous mutations in other cilia genes could exacerbate retinal degeneration, we bred cep290fh297/fh297 mutants to arl13b, ahi1, and cc2d2a mutant zebrafish lines. While cep290fh297/fh297 mutants lacking a single allele of these genes did not exhibit accelerated photoreceptor degeneration, loss of one alleles of arl13b or ahi1 reduced visual performance in optokinetic response assays at 5 days post fertilization. Our results indicate that the cep290fh297/fh297 mutant is a useful model to study the role of genetic modifiers on photoreceptor degeneration in zebrafish and to explore how progressive photoreceptor degeneration influences regeneration in adult zebrafish.Nonstandard abbreviationsBBSBardet-Biedl SyndromeCOScone outer segmentsDpfDays post fertilizationGNB1rod transducin β subunitGRK1rhodopsin kinaseJTBSJoubert SyndromeLCALeber Congenital AmaurosisMKSMeckel SyndromeNPHPnephronophthisisOKRoptokinetic responsePNApeanut agglutinin lectinROSrod outer segmentsRP2Retinitis Pigmentosa 2

MpdzNull Allele in an Avian Model of Retinal Degeneration and Mutations in Human Leber Congenital Amaurosis and Retinitis Pigmentosa

2011 ◽  
Vol 52 (10) ◽  
pp. 7432 ◽  
Author(s):  
Manir Ali ◽  
Paul M. Hocking ◽  
Martin McKibbin ◽  
Sorcha Finnegan ◽  
Mike Shires ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Retinal Degeneration ◽  
Leber Congenital Amaurosis

scholarly journals Development of an optimized AAV2/5 gene therapy vector for Leber congenital amaurosis owing to defects in RPE65

Gene Therapy ◽  
2016 ◽  
Vol 23 (12) ◽  
pp. 857-862 ◽  
Author(s):  
A Georgiadis ◽  
Y Duran ◽  
J Ribeiro ◽  
L Abelleira-Hervas ◽  
S J Robbie ◽  
...  
Keyword(s):  
Retinal Degeneration ◽  
Early Stage ◽  
Rod Photoreceptor ◽  
Adeno Associated Virus ◽  
Gene Therapy Vector ◽  
Leber Congenital Amaurosis ◽  
Inherited Retinal Dystrophies ◽  
Retinal Dystrophies ◽  
Serotype 5 ◽  
Subretinal Injection

Abstract Leber congenital amaurosis is a group of inherited retinal dystrophies that cause severe sight impairment in childhood; RPE65-deficiency causes impaired rod photoreceptor function from birth and progressive impairment of cone photoreceptor function associated with retinal degeneration. In animal models of RPE65 deficiency, subretinal injection of recombinant adeno-associated virus (AAV) 2/2 vectors carrying RPE65 cDNA improves rod photoreceptor function, and intervention at an early stage of disease provides sustained benefit by protecting cone photoreceptors against retinal degeneration. In affected humans, administration of these vectors has resulted to date in relatively modest improvements in photoreceptor function, even when retinal degeneration is comparatively mild, and the duration of benefit is limited by progressive retinal degeneration. We conclude that the demand for RPE65 in humans is not fully met by current vectors, and predict that a more powerful vector will provide more durable benefit. With this aim we have modified the original AAV2/2 vector to generate AAV2/5-OPTIRPE65. The new configuration consists of an AAV vector serotype 5 carrying an optimized hRPE65 promoter and a codon-optimized hRPE65 gene. In mice, AAV2/5-OPTIRPE65 is at least 300-fold more potent than our original AAV2/2 vector.

scholarly journals CRB1 Gene Mutation Causing Different Phenotypes of Leber Congenital Amaurosis in Siblings

2019 ◽  
Author(s):  
Shaheryar Ahmed Khan ◽  
Achim Richard Nestel
Keyword(s):  
Case Report ◽  
Retinitis Pigmentosa ◽  
Gene Mutation ◽  
Rare Case ◽  
Single Gene ◽  
Genetic Mutation ◽  
Cone Dystrophy ◽  
Severe Phenotype ◽  
Leber Congenital Amaurosis ◽  
Retinal Dystrophies

Purpose: We report a rare case of CRB1 gene mutation in two siblings (sisters) affected with the exact same genetic mutation on both CRB1 genes resulting in varying phenotypes. Case Report: CRB1 gene mutation in this case has resulted in causing varying degrees of Leber congenital amaurosis (LCA) in both sisters with a more severe phenotype in the older sibling causing LCA-8 with retinitis pigmentosa spectrum in both eyes and a milder phenotype causing LCA-8 with less severe rod cone dystrophy in the younger sister. Conclusion: In summary, the mechanisms of varying phenotypes resulting from CRB1 genetic mutation are still not well understood. We concluded that the presence of different phenotypes associated with identical genotypic mutation of a single gene in siblings or in a family is important especially when dealing with retinal dystrophies.

scholarly journals Nutraceutical Supplementation Ameliorates Visual Function, Retinal Degeneration, and Redox Status in rd10 Mice

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1033
Author(s):  
Lorena Olivares-González ◽  
Sheyla Velasco ◽  
Isabel Campillo ◽  
David Salom ◽  
Emilio González-García ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Retinal Degeneration ◽  
Antioxidant Properties ◽  
Photoreceptor Cells ◽  
Redox Status ◽  
Inherited Retinal Dystrophies ◽  
Stress Markers ◽  
Retinal Dystrophies ◽  
Progressive Degeneration ◽  
Light Stimuli

Background: Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by progressive degeneration of photoreceptor cells. Ocular redox status is altered in RP suggesting oxidative stress could contribute to their progression. In this study, we investigated the effect of a mixture of nutraceuticals with antioxidant properties (NUT) on retinal degeneration in rd10 mice, a model of RP. Methods: NUT was orally administered to rd10 mice from postnatal day (PD) 9 to PD18. At PD18 retinal function and morphology were examined by electroretinography (ERG) and histology including TUNEL assay, immunolabeling of microglia, Müller cells, and poly ADP ribose polymers. Retinal redox status was determined by measuring the activity of antioxidant enzymes and some oxidative stress markers. Gene expression of the cytokines IL-6, TNFα, and IL-1β was assessed by real-time PCR. Results: NUT treatment delayed the loss of photoreceptors in rd10 mice partially preserving their electrical responses to light stimuli. Moreover, it ameliorated redox status and reduced inflammation including microglia activation, upregulation of cytokines, reactive gliosis, and PARP overactivation. Conclusions: NUT ameliorated retinal functionality and morphology at early stages of RP in rd10 mice. This formulation could be useful as a neuroprotective approach for patients with RP in the future.

scholarly journals Genotypes Predispose Phenotypes—Clinical Features and Genetic Spectrum of ABCA4-Associated Retinal Dystrophies

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1421
Author(s):  
Yu-Chi Sung ◽  
Chang-Hao Yang ◽  
Chung-May Yang ◽  
Chao-Wen Lin ◽  
Ding-Siang Huang ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Retinal Degeneration ◽  
Medical Center ◽  
Fundus Autofluorescence ◽  
Genetic Diagnosis ◽  
Common Disease ◽  
Genetic Characteristics ◽  
Retinal Dystrophies ◽  
High Prevalence ◽  
Abca4 Gene

The ABCA4 gene is one of the most common disease-causing genes of inherited retinal degeneration. In this study, we report different phenotypes of ABCA4-associated retinal dystrophies in the Taiwanese population, its clinical progression, and its relationship with genetic characteristics. Thirty-seven subjects were recruited and all patients underwent serial ophthalmic examinations at a single medical center. Fundus autofluorescence (FAF) images were quantified for clinical evaluation, and panel-based next-generation sequencing testing was performed for genetic diagnosis. Visual preservation, disease progression, and genotype–phenotype correlation were analyzed. In this cohort, ABCA4-associated retinal degeneration presented as Stargardt disease 1 (STGD1, 62.16%), retinitis pigmentosa (32.43%), and cone-rod dystrophy (5.41%). STGD1 could be further divided into central and dispersed types. In each phenotype, the lesion areas quantified by FAF increased with age (p < 0.01) and correlated with poorer visual acuity. However, three patients had the foveal sparing phenotype and had relatively preserved visual acuity. Forty-two ABCA4 variants were identified as disease-causing, with c.1804C>T (p.Arg602Trp) the most frequent (37.84%). Patients with a combination of severe/null variants could have more extensive phenotypes, such as arRP and dispersed STGD1. This is the first cohort study of ABCA4-associated retinal degeneration in Taiwan with wide spectrums of both genotypic and phenotypic characteristics. An extremely high prevalence of c.1804C>T, which has not been reported in East Asia before, was noted. The extensiveness of retinal involvement might be regarded as a spectrum of ABCA4-associated retinal dystrophies. Different types of genetic variations could lead to distinctive phenotypes, according to the coding impact of variants.

Short-term high-fat feeding exacerbates degeneration in retinitis pigmentosa by promoting retinal oxidative stress and inflammation

2021 ◽  
Vol 118 (43) ◽  
pp. e2100566118
Author(s):  
Oksana Kutsyr ◽  
Agustina Noailles ◽  
Natalia Martínez-Gil ◽  
Lucía Maestre-Carballa ◽  
Manuel Martinez-Garcia ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Retinitis Pigmentosa ◽  
Retinal Degeneration ◽  
Gut Microbiome ◽  
Cell Activation ◽  
High Fat ◽  
Short Term ◽  
Oxidative Markers ◽  
Degenerative Disorders ◽  
Inflammatory State

A high-fat diet (HFD) can induce hyperglycemia and metabolic syndromes that, in turn, can trigger visual impairment. To evaluate the acute effects of HFD feeding on retinal degeneration, we assessed retinal function and morphology, inflammatory state, oxidative stress, and gut microbiome in dystrophic retinal degeneration 10 (rd10) mice, a model of retinitis pigmentosa, fed an HFD for 2 to 3 wk. Short-term HFD feeding impaired retinal responsiveness and visual acuity and enhanced photoreceptor degeneration, microglial cell activation, and Müller cell gliosis. HFD consumption also triggered the expression of inflammatory and oxidative markers in rd10 retinas. Finally, an HFD caused gut microbiome dysbiosis, increasing the abundance of potentially proinflammatory bacteria. Thus, HFD feeding drives the pathological processes of retinal degeneration by promoting oxidative stress and activating inflammatory-related pathways. Our findings suggest that consumption of an HFD could accelerate the progression of the disease in patients with retinal degenerative disorders.

Mutation analysis of Leber congenital amaurosis-associated genes in patients with retinitis pigmentosa

2014 ◽  
Vol 11 (3) ◽  
pp. 1827-1832 ◽  
Author(s):  
TAO SHEN ◽  
LIPING GUAN ◽  
SHIQIANG LI ◽  
JIANGUO ZHANG ◽  
XUESHAN XIAO ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Mutation Analysis ◽  
Leber Congenital Amaurosis

scholarly journals Microglia dynamics in retinitis pigmentosa model: formation of fundus whitening and autofluorescence as an indicator of activity of retinal degeneration

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Kenichi Makabe ◽  
Sunao Sugita ◽  
Michiko Mandai ◽  
Yoko Futatsugi ◽  
Masayo Takahashi
Keyword(s):  
Retinitis Pigmentosa ◽  
Retinal Degeneration ◽  
Outer Nuclear Layer ◽  
Fundus Autofluorescence ◽  
Fundus Photography ◽  
Photoreceptor Outer Segments ◽  
Diagnostic Interpretation ◽  
Model Formation ◽  
Thinning Rate

Abstract In patients with retinitis pigmentosa (RP), color fundus photography and fundus autofluorescence (FAF) have been used to estimate the disease progression. To understand the origin and the diagnostic interpretation of the fundus color and FAF, we performed in vivo imaging of fundus color and FAF together with histological analyses of the retinal degeneration process using the RP model mice, rd10. FAF partly represented the accumulation of microglia in the photoreceptor outer segments. Fundus whitening suggested the presence of apoptotic cells, which spatiotemporally preceded increase in FAF. We observed two patterns of FAF localization, arcuate and diffuse, each indicating different pattern of apoptosis, wavy and diffuse, respectively. Diffuse pattern of apoptosis was suppressed in dark-raised rd10 mice, in which outer nuclear layer (ONL) loss was significantly suppressed. The occupancy of FAF correlated with the thinning rate of the ONL. Fractalkine, a microglia chemotactic factor, was detected in apoptotic photoreceptors, suggesting chemokine-induced recruitment of microglia into the ONL, which paralleled with accelerated ONL loss and increased FAF occupancy. Thus, we propose that the degree of photoreceptor apoptosis and the rate of ONL thinning in RP patients might be read from the fundus color and the FAF.

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