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Yu Y, Xia X, Li H, Zhang Y, Zhou X, Jiang H. A new rhodopsin R135W mutation induces endoplasmic reticulum stress and apoptosis in retinal pigment epithelial cells. J Cell Physiol 2019; 234:14100-14108. [PMID: 30635925 DOI: 10.1002/jcp.28100] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 12/07/2018] [Indexed: 01/21/2023]
Affiliation(s)
- Yixin Yu
- Department of Ophthalmology Xiangya Hospital, Central South University Changsha China
| | - Xiaobo Xia
- Department of Ophthalmology Xiangya Hospital, Central South University Changsha China
| | - Haibo Li
- Department of Ophthalmology Xiangya Hospital, Central South University Changsha China
| | - Yangzhou Zhang
- Department of Ophthalmology Xiangya Hospital, Central South University Changsha China
| | - Xiaoyun Zhou
- Department of Ophthalmology Xiangya Hospital, Central South University Changsha China
| | - Haibo Jiang
- Department of Ophthalmology Xiangya Hospital, Central South University Changsha China
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Yu X, Shi W, Cheng L, Wang Y, Chen D, Hu X, Xu J, Xu L, Wu Y, Qu J, Gu F. Identification of a rhodopsin gene mutation in a large family with autosomal dominant retinitis pigmentosa. Sci Rep 2016; 6:19759. [PMID: 26794436 PMCID: PMC4726306 DOI: 10.1038/srep19759] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 12/14/2015] [Indexed: 11/09/2022] Open
Abstract
Retinitis pigmentosa (RP) is a genetically highly heterogeneous retinal disease and one of the leading causes of blindness in the world. Next-generation sequencing technology has enormous potential for determining the genetic etiology of RP. We sought to identify the underlying genetic defect in a 35-year-old male from an autosomal-dominant RP family with 14 affected individuals. By capturing next-generation sequencing (CNGS) of 144 genes associated with retinal diseases, we identified eight novel DNA variants; however, none of them cosegregated for all the members of the family. Further analysis of the CNGS data led to identification of a recurrent missense mutation (c.403C > T, p.R135W) in the rhodopsin (RHO) gene, which cosegregated with all affected individuals in the family and was not observed in any of the unaffected family members. The p.R135W mutation has a reference single nucleotide polymorphism (SNP) ID (rs104893775), and it appears to be responsible for the disease in this large family. This study highlights the importance of examining NGS data with reference SNP IDs. Thus, our study is important for data analysis of NGS-based clinical genetic diagnoses.
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Affiliation(s)
- Xinping Yu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
| | - Wei Shi
- Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University, Beijing 100045 China
| | - Lulu Cheng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
| | - Yanfang Wang
- Zhejiang Key Laboratory of Medical Genetics, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035 China
| | - Ding Chen
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
| | - Xuting Hu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
| | - Jinling Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
| | - Limin Xu
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou, Zhengzhou University, Henan 450052 China
| | - Yaming Wu
- Department of Ophthalmology, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000 China
| | - Jia Qu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
| | - Feng Gu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang 325027 China
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Retinal histopathology in eyes from patients with autosomal dominant retinitis pigmentosa caused by rhodopsin mutations. Graefes Arch Clin Exp Ophthalmol 2015. [PMID: 26202387 DOI: 10.1007/s00417-015-3099-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
PURPOSE To evaluate the histopathology in donor eyes from patients with autosomal dominant retinitis pigmentosa (ADRP) caused by p.P23H, p.P347T and p.P347L rhodopsin ( RHO ) gene mutations. METHODS Eyes from a 72-year-old male (donor 1), an 83-year-old female (donor 2), an 80-year-old female (donor 3), and three age-similar normal eyes were examined macroscopically, by scanning laser ophthalmoscopy and optical coherence tomography imaging. Perifoveal and peripheral pieces were processed for microscopy and immunocytochemistry with markers for photoreceptor cells. RESULTS DNA analysis revealed RHO mutations c.68C>A (p.P23H) in donor 1, c.1040C>T (p.P347L) in donor 2 and c.1039C>A (p.P347T) in donor 3. Histology of the ADRP eyes showed retinas with little evidence of stratified nuclear layers in the periphery and a prominent inner nuclear layer present in the perifoveal region in the p.P23H and p.P347T eyes, while it was severely atrophic in the p.P347L eye. The p.P23H and p.P347T mutations cause a profound loss of rods in both the periphery and perifovea, while the p.P347L mutation displays near complete absence of rods in both regions. All three rhodopsin mutations caused a profound loss of cones in the periphery. The p.P23H and p.P347T mutations led to the presence of highly disorganized cones in the perifovea. However, the p.P347L mutation led to near complete absence of cones also in the perifovea. CONCLUSIONS Our results support clinical findings indicating that mutations affecting residue P347 develop more severe phenotypes than those affecting P23. Furthermore, our results indicate a more severe phenotype in the p.P347L retina as compared to the p.P347T retina.
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Kartasasmita A, Fujiki K, Iskandar E, Sovani I, Fujimaki T, Murakami A. A novel nonsense mutation in rhodopsin gene in two Indonesian families with autosomal recessive retinitis pigmentosa. Ophthalmic Genet 2010; 32:57-63. [PMID: 21174529 DOI: 10.3109/13816810.2010.535892] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To report a novel, identical nonsense mutation in the rhodopsin (RHO) gene in two Indonesian families with autosomal recessive retinitis pigmentosa (arRP). METHODS Mutation screening for the RHO gene was performed in 38 unrelated patients with retinitis pigmentosa (RP) by direct sequencing. Clinical features were also characterized, through complete ophthalmologic examination. Family members of RP patients testing positive for the RHO gene were subjected to genetic and clinical examination. To assess the founder effect in the two families, haplotype analysis also was performed. RESULTS A novel homozygous nonsense mutation was detected in two patients by a G to A transition at nucleotide position 482 in exon 2 of the RHO gene, resulting in substitution of a tryptophan-to-stop at codon 161 (c.482G>A, p.W161X). Examination of family members of these 2 patients showed that the affected members were homozygous and unaffected carriers were heterozygous for the p.W161X mutation. Haplotype analysis revealed that members of the two families carried the same disease-associated variants in markers (IVS1 RHO and D3S2322). No p.W161X mutations were detected in 45 normal Indonesian subjects, nor were any mutations detected in exons 1-5 of the RHO gene in the remaining 36 RP patients. CONCLUSION We detected a novel, recessive nonsense mutation (p.W161X) in the RHO gene of two families through mutation screening of RHO in 38 Indonesian RP patients. Haplotype analysis suggested that p.W161X was the founder mutation.
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Affiliation(s)
- Arief Kartasasmita
- Department of Ophthalmology, Faculty of Medicine, Padjadjaran University/Cicendo National Eye Hospital, Bandung, Indonesia.
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Audo I, Manes G, Mohand-Saïd S, Friedrich A, Lancelot ME, Antonio A, Moskova-Doumanova V, Poch O, Zanlonghi X, Hamel CP, Sahel JA, Bhattacharya SS, Zeitz C. Spectrum of rhodopsin mutations in French autosomal dominant rod-cone dystrophy patients. Invest Ophthalmol Vis Sci 2010; 51:3687-700. [PMID: 20164459 DOI: 10.1167/iovs.09-4766] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
UNLABELLED PURPOSE. To identify the prevalence of rhodopsin (RHO) mutations in French patients with autosomal dominant rod-cone dystrophies (adRPs). Methods. Detailed phenotypic characterization was performed, including precise family history, best corrected visual acuity with the ETDRS chart, slit lamp examination, kinetic and static perimetry, full-field and multifocal electroretinography (ERG), fundus autofluorescence imaging (FAF), and optical coherence tomography (OCT). For genetic diagnosis, genomic DNA of 79 families was isolated by standard METHODS The coding exons and flanking intronic regions of RHO were PCR amplified, purified, and sequenced in the index patient. RESULTS. Of this French adRP sample, 16.5% carried an RHO mutation. Three different families showed a novel mutation (p. Leu88Pro, p.Met207Lys and p.Gln344Pro), while ten unrelated families showed recurrent, previously published mutations (p.Asn15Ser, p.Leu131Pro, p.Arg135Trp, p.Ser334GlyfsX21 and p.Pro347Leu). All mutations co-segregated with the phenotype within a family, and the novel mutations were not identified in control samples. CONCLUSIONS. This study revealed that the prevalence of RHO mutations in French adRP patients is in accordance with that in other studies from Europe. Most of the changes identified herein reflect recurrent mutations, within which p.Pro347Leu substitution is the most prevalent. Nevertheless, almost one fourth of the changes are novel, indicating that, although RHO is the first gene implicated and probably the most studied gene in RP, it is still important performing mutation analysis in RHO to detect novel changes. The detailed phenotype-genotype analyses in all available family members deliver the basis for therapeutic approaches in those families.
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Matias-Florentino M, Ayala-Ramirez R, Graue-Wiechers F, Zenteno JC. Molecular Screening ofRhodopsinandPeripherin/RDSGenes in Mexican Families with Autosomal Dominant Retinitis Pigmentosa. Curr Eye Res 2009; 34:1050-6. [DOI: 10.3109/02713680903283169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Iannaccone A, Man D, Waseem N, Jennings BJ, Ganapathiraju M, Gallaher K, Reese E, Bhattacharya SS, Klein-Seetharaman J. Retinitis pigmentosa associated with rhodopsin mutations: Correlation between phenotypic variability and molecular effects. Vision Res 2006; 46:4556-67. [PMID: 17014888 DOI: 10.1016/j.visres.2006.08.018] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Revised: 08/01/2006] [Accepted: 08/03/2006] [Indexed: 11/17/2022]
Abstract
Similar retinitis pigmentosa (RP) phenotypes can result from mutations affecting different rhodopsin regions, and distinct amino acid substitutions can cause different RP severity and progression rates. Specifically, both the R135L and R135W mutations (cytoplasmic end of H3) result in diffuse, severe disease (class A), but R135W causes more severe and more rapidly progressive RP than R135L. The P180A and G188R mutations (second intradiscal loop) exhibit a mild phenotype with regional variability (class B1) and diffuse disease of moderate severity (class B2), respectively. Computational and in vitro studies of these mutants provide molecular insights into this phenotypic variability.
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Affiliation(s)
- Alessandro Iannaccone
- Hamilton Eye Institute, Department of Ophthalmology, Retinal Degeneration and Ophthalmic Genetics Service, University of Tennessee Health Science Center, 930 Madison Avenue, Suit 731, Memphis, TN 38163, USA
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Senin II, Bosch L, Ramon E, Zernii EY, Manyosa J, Philippov PP, Garriga P. Ca2+/recoverin dependent regulation of phosphorylation of the rhodopsin mutant R135L associated with retinitis pigmentosa. Biochem Biophys Res Commun 2006; 349:345-52. [PMID: 16934219 DOI: 10.1016/j.bbrc.2006.08.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Accepted: 08/11/2006] [Indexed: 11/19/2022]
Abstract
No single molecular mechanism accounts for the effect of mutations in rhodopsin associated with retinitis pigmentosa. Here we report on the specific effect of a Ca2+/recoverin upon phosphorylation of the autosomal dominant retinitis pigmentosa R135L rhodopsin mutant. This mutant shows specific features like impaired G-protein signaling but enhanced phosphorylation in the shut-off process. We now report that R135L hyperphosphorylation by rhodopsin kinase is less efficiently inhibited by Ca2+/recoverin than wild-type rhodopsin. This suggests an involvement of Ca2+/recoverin into the molecular pathogenic effect of the mutation in retinitis pigmentosa which is the cause of rod photoreceptor cell degeneration. This new proposed role of Ca2+/recoverin may be one of the specific features of the proposed new Type III class or rhodopsin mutations associated with retinitis pigmentosa.
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Affiliation(s)
- Ivan I Senin
- Department of Cell Signalling, A. N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Russia
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Iannaccone A, Mura M, Dyka FM, Ciccarelli ML, Yashar BM, Ayyagari R, Jablonski MM, Molday RS. An unusual X-linked retinoschisis phenotype and biochemical characterization of the W112C RS1 mutation. Vision Res 2006; 46:3845-52. [PMID: 16884758 DOI: 10.1016/j.visres.2006.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2006] [Revised: 06/02/2006] [Accepted: 06/09/2006] [Indexed: 10/24/2022]
Abstract
A 52-year-old subject harboring an RS1 gene W112C mutation presented with a prominent and asymmetric tapetal-like retinal sheen. Transient ERG responses were smaller and slower in the eye with the more extensive sheen, an association that, to our knowledge, had not been previously reported. An ON-pathway dysfunction explained the abnormalities of the transient but not those of the flicker ERGs. Although in vitro studies showed that the W112C mutant retinoschisin is present only in the cellular fraction and is not secreted, disease expression was remarkably mild, consistent with the notion of the existence of genetic and/or epigenetic disease modifiers.
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Affiliation(s)
- Alessandro Iannaccone
- Hamilton Eye Institute, Department of Ophthalmology, University of Tennessee Health Science Center, 930 Madison Avenue, Suite 731, Memphis, TN 38163, USA.
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Oh KT, Oh DM, Weleber RG, Stone EM, Parikh A, White J, Deboer-Shields KA, Streb L, Vallar C. Genotype-phenotype correlation in a family with Arg135Leu rhodopsin retinitis pigmentosa. Br J Ophthalmol 2004; 88:1533-7. [PMID: 15548806 PMCID: PMC1772449 DOI: 10.1136/bjo.2004.043653] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To describe the clinical characteristics and disease course of a large family with retinitis pigmentosa (RP) from an Arg135Leu change in rhodopsin. METHODS 29 patients in this family were evaluated. Goldmann visual fields were performed on 14 affected individuals, Ganzfeld electroretinography (ERG) on eight individuals (11-56 years), and blood samples collected on 10 individuals (11-58 years). Patient visual field data were compared with previously reported patients with different rhodopsin mutations using linear regression. RESULTS An Arg135Leu mutation was identified in rhodopsin. Distinct stages of clinical evolution were identified for this family ranging from normal, white dots, classic bone spicules and, finally, ending with extensive retinal pigment epithelium (RPE) atrophy. 9/16 patients over the age of 20 years also demonstrated marked macular atrophy. All patients who underwent full field ERG testing demonstrated non-recordable ERGs. The overall regression model comparing solid angles of visual fields from patients with rhodopsin mutations (Pro23His, Pro347Ala, Arg135Leu) shows significant effects for age (p = 0.0005), mutation (p = 0.0014), and interaction between age and mutation (p = 0.018) with an R(2) of 0.407. CONCLUSIONS An Arg135Leu change in rhodopsin results in a severe form of RP that evolves through various fundus appearances that include white dots early in life and classic appearing RP later. This transmembrane change in rhodopsin proves to be more severe than in a family with an intradiscal change and a family with a cytoplasmic change.
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Affiliation(s)
- K T Oh
- Department of Ophthalmology, University of North Carolina, Chapel Hill, NC, USA
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Chuang JZ, Vega C, Jun W, Sung CH. Structural and functional impairment of endocytic pathways by retinitis pigmentosa mutant rhodopsin-arrestin complexes. J Clin Invest 2004; 114:131-40. [PMID: 15232620 PMCID: PMC437971 DOI: 10.1172/jci21136] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2004] [Accepted: 05/11/2004] [Indexed: 11/17/2022] Open
Abstract
Retinitis pigmentosa (RP) is a clinically and genetically heterogeneous degenerative eye disease. Mutations at Arg135 of rhodopsin are associated with a severe form of autosomal dominant RP. This report presents evidence that Arg135 mutant rhodopsins (e.g., R135L, R135G, and R135W) are hyperphosphorylated and bind with high affinity to visual arrestin. Mutant rhodopsin recruits the cytosolic arrestin to the plasma membrane, and the rhodopsin-arrestin complex is internalized into the endocytic pathway. Furthermore, the rhodopsin-arrestin complexes alter the morphology of endosomal compartments and severely damage receptor-mediated endocytic functions. The biochemical and cellular defects of Arg135 mutant rhodopsins are distinct from those previously described for class I and class II RP mutations, and, hence, we propose that they be named class III. Impaired endocytic activity may underlie the pathogenesis of RP caused by class III rhodopsin mutations.
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Affiliation(s)
- Jen-Zen Chuang
- Department of Ophthalmology, The Margaret M. Dyson Research Institute, New York, NY 10021, USA
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Chuang JZ, Vega C, Jun W, Sung CH. Structural and functional impairment of endocytic pathways by retinitis pigmentosa mutant rhodopsin-arrestin complexes. J Clin Invest 2004. [DOI: 10.1172/jci200421136] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Tessitore A, Toniato E, Gulino A, Frati L, Ricevuto E, Vadalà M, Vingolo E, Martinotti S. Prenatal diagnosis of a rhodopsin mutation using chemical cleavage of the mismatch. Prenat Diagn 2002; 22:380-4. [PMID: 12001191 DOI: 10.1002/pd.263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Mutations of the rhodopsin gene are responsible for autosomal dominant or recessive retinitis pigmentosa (RP). The present study reports the first prenatal diagnosis performed on chorionic villi biopsy of a pregnant woman affected by a severe form of autosomal dominant transmitted RP, due to the Arg135Trp substitution. METHODS The rhodopsin gene was analysed by automated direct sequencing and, for the first time, by fluorescence-assisted mismatch analysis (FAMA). The latter is an inexpensive, rapid and particularly sensitive method, based on the chemical cleavage of the mismatch in heteroduplex DNA molecules marked with strand-specific fluorophores. RESULTS FAMA is a feasible procedure for prenatal molecular diagnosis of rhodopsin mutations. The redundancy of signals obtained by FAMA and its sensitivity make it suitable for identifying exactly the position of the mutation and the nucleotide substitution. CONCLUSIONS An association is proposed between FAMA and automated direct sequencing procedures, in order to achieve optimal results in terms of reliability for prenatal diagnosis of rhodopsin mutations.
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Abstract
The crystal structure of rod cell visual pigment rhodopsin was recently solved at 2.8-A resolution. A critical evaluation of a decade of structure-function studies is now possible. It is also possible to begin to explain the structural basis for several unique physiological properties of the vertebrate visual system, including extremely low dark noise levels as well as high gain and color detection. The ligand-binding pocket of rhodopsin is remarkably compact, and several apparent chromophore-protein interactions were not predicted from extensive mutagenesis or spectroscopic studies. The transmembrane helices are interrupted or kinked at multiple sites. An extensive network of interhelical interactions stabilizes the ground state of the receptor. The helix movement model of receptor activation, which might apply to all G protein-coupled receptors (GPCRs) of the rhodopsin family, is supported by several structural elements that suggest how light-induced conformational changes in the ligand-binding pocket are transmitted to the cytoplasmic surface. The cytoplasmic domain of the receptor is remarkable for a carboxy-terminal helical domain extending from the seventh transmembrane segment parallel to the bilayer surface. Thus the cytoplasmic surface appears to be approximately the right size to bind to the transducin heterotrimer in a one-to-one complex. Future high-resolution structural studies of rhodopsin and other GPCRs will form a basis to elucidate the detailed molecular mechanism of GPCR-mediated signal transduction.
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Affiliation(s)
- S T Menon
- Howard Hughes Medical Institute, Laboratory of Molecular Biology and Biochemistry, The Rockefeller University, New York, New York 10021, USA
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Iannaccone A, De Propris G, Roncati S, Rispoli E, Del Porto G, Pannarale MR. The ocular phenotype of the Bardet-Biedl syndrome. Comparison to non-syndromic retinitis pigmentosa. Ophthalmic Genet 1997; 18:13-26. [PMID: 9134546 DOI: 10.3109/13816819709057879] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To investigate 20 patients affected with Bardet-Biedl (BB) syndrome and compare them to an age-matched group of 70 non-syndromic patients with retinitis pigmentosa (RP) to identify hallmarks peculiar to the BB phenotype. METHODS Patients were examined clinically and with functional tests (color vision, kinetic perimetry, electroretinography, ocular motility tests). Fundus findings were numerically graded for statistical purposes. RESULTS Recurrent ocular features in BB patients were early and severe reduction of visual acuity, constantly altered color vision, high incidence of strabismus and nystagmus, mild-to-severe atrophic changes of the optic disc, and frequently absent or minimal pigmentary retinal changes. Visual acuity was more closely correlated to optic disc than to macular conditions. These findings were remarkably different from non-syndromic RP. CONCLUSIONS This investigation further suggests that retinopathy in BB syndrome has features distinctive from those in non-syndromic RP. The early occurrence of optic disc atrophy in the BB syndrome, even in those patients with healthy maculas, suggests that optic atrophy could often be primary in nature and might play a major role in decreasing central vision in BB patients. Variability of some findings is in line with the documented heterogeneity of the BB syndrome.
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Affiliation(s)
- A Iannaccone
- Institute of Ophthalmology, University of Rome La Sapienza, Italy
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