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Aljammal R, Saravanan T, Guan T, Rhodes S, Robichaux MA, Ramamurthy V. Excessive tubulin glutamylation leads to progressive cone-rod dystrophy and loss of outer segment integrity. Hum Mol Genet 2024; 33:802-817. [PMID: 38297980 DOI: 10.1093/hmg/ddae013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/29/2023] [Accepted: 01/09/2024] [Indexed: 02/02/2024] Open
Abstract
Mutations in Cytosolic Carboxypeptidase-like Protein 5 (CCP5) are associated with vision loss in humans. To decipher the mechanisms behind CCP5-associated blindness, we generated a novel mouse model lacking CCP5. In this model, we found that increased tubulin glutamylation led to progressive cone-rod dystrophy, with cones showing a more pronounced and earlier functional loss than rod photoreceptors. The observed functional reduction was not due to cell death, levels, or the mislocalization of major phototransduction proteins. Instead, the increased tubulin glutamylation caused shortened photoreceptor axonemes and the formation of numerous abnormal membranous whorls that disrupted the integrity of photoreceptor outer segments (OS). Ultimately, excessive tubulin glutamylation led to the progressive loss of photoreceptors, affecting cones more severely than rods. Our results highlight the importance of maintaining tubulin glutamylation for normal photoreceptor function. Furthermore, we demonstrate that murine cone photoreceptors are more sensitive to disrupted tubulin glutamylation levels than rods, suggesting an essential role for axoneme in the structural integrity of the cone outer segment. This study provides valuable insights into the mechanisms of photoreceptor diseases linked to excessive tubulin glutamylation.
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Affiliation(s)
- Rawaa Aljammal
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, 64 Medical Center Dr., Morgantown, WV 26506, United States
- Department of Ophthalmology and Visual Sciences, One Stadium Dr, West Virginia University, Morgantown, WV 26506, United States
| | - Thamaraiselvi Saravanan
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, 64 Medical Center Dr., Morgantown, WV 26506, United States
- Department of Ophthalmology and Visual Sciences, One Stadium Dr, West Virginia University, Morgantown, WV 26506, United States
| | - Tongju Guan
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, 64 Medical Center Dr., Morgantown, WV 26506, United States
- Department of Ophthalmology and Visual Sciences, One Stadium Dr, West Virginia University, Morgantown, WV 26506, United States
| | - Scott Rhodes
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, 64 Medical Center Dr., Morgantown, WV 26506, United States
- Department of Ophthalmology and Visual Sciences, One Stadium Dr, West Virginia University, Morgantown, WV 26506, United States
| | - Michael A Robichaux
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, 64 Medical Center Dr., Morgantown, WV 26506, United States
- Department of Ophthalmology and Visual Sciences, One Stadium Dr, West Virginia University, Morgantown, WV 26506, United States
| | - Visvanathan Ramamurthy
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, 64 Medical Center Dr., Morgantown, WV 26506, United States
- Department of Ophthalmology and Visual Sciences, One Stadium Dr, West Virginia University, Morgantown, WV 26506, United States
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2
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Kolawole OU, Gregory-Evans CY, Bikoo R, Huang AZ, Gregory-Evans K. Novel pathogenic variants in Tubulin Tyrosine Like 5 ( TTLL5) associated with cone-dominant retinal dystrophies and an abnormal optical coherence tomography phenotype. Mol Vis 2023; 29:329-337. [PMID: 38264610 PMCID: PMC10805330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 12/10/2023] [Indexed: 01/25/2024] Open
Abstract
Purpose Autosomal recessive cone and cone-rod dystrophies (CD/CRD) are inherited forms of vison loss. Here, we report on and correlate the clinical phenotypes with the underlying genetic mutations. Methods Clinical information was collected from subjects, including a family history with a chart review. They underwent a full ophthalmic examination, including best-corrected visual acuity, direct and indirect ophthalmoscopy, color vision testing, color fundus photography, contrast sensitivity, autofluorescence, and spectral domain-optical coherence tomography (SD-OCT), and full-field electroretinography. Next-generation panel-based genetic testing was used to identify DNA variants in subject buccal swab samples. Results Genetic testing in two patients revealed three novel variants in the TTLL5 gene associated with CD/CRD: two missense variants (c.1433G>A;p.(Arg478Gln), c.241C>G;p.(Leu81Val), and one loss-of-function variant (c.2384_2387del;p.(Ala795Valfs*9). Based on in-silico analysis, structural modeling, and comparison to previously reported mutations, these novel variants are very likely to be disease-causing mutations. Combining retinal imaging with SD-OCT analysis, we observed an unusual sheen in the CD/CRD phenotypes. Conclusion Based on the protein domain location of novel TTLL5 variants and the localization of TTLL5 to the connecting cilium, we conclude that the CD/CRD disease phenotype is characterized as a ciliopathy caused by protein tracking dysfunction. This initially affects cone photoreceptors, where photoreceptor cilia express a high level of TTLL5, but extends to rod photoreceptors over time. Fundus photography correlated with SD-OCT imaging suggests that the macular sheen characteristically seen with TTLL5 mutations derives from the photoreceptor's outer segments at the posterior pole.
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Affiliation(s)
- Olubayo U Kolawole
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
| | | | - Riyaz Bikoo
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
| | - Albert Z Huang
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
| | - Kevin Gregory-Evans
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
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3
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Bonetti G, Cozza W, Bernini A, Kaftalli J, Mareso C, Cristofoli F, Medori MC, Colombo L, Martella S, Staurenghi G, Salvetti AP, Falsini B, Placidi G, Attanasio M, Pertile G, Bengala M, Bosello F, Petracca A, D’Esposito F, Toschi B, Lanzetta P, Ricci F, Viola F, Marceddu G, Bertelli M. Towards a Long-Read Sequencing Approach for the Molecular Diagnosis of RPGR ORF15 Genetic Variants. Int J Mol Sci 2023; 24:16881. [PMID: 38069202 PMCID: PMC10706286 DOI: 10.3390/ijms242316881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
Sequencing of the low-complexity ORF15 exon of RPGR, a gene correlated with retinitis pigmentosa and cone dystrophy, is difficult to achieve with NGS and Sanger sequencing. False results could lead to the inaccurate annotation of genetic variants in dbSNP and ClinVar databases, tools on which HGMD and Ensembl rely, finally resulting in incorrect genetic variants interpretation. This paper aims to propose PacBio sequencing as a feasible method to correctly detect genetic variants in low-complexity regions, such as the ORF15 exon of RPGR, and interpret their pathogenicity by structural studies. Biological samples from 75 patients affected by retinitis pigmentosa or cone dystrophy were analyzed with NGS and repeated with PacBio. The results showed that NGS has a low coverage of the ORF15 region, while PacBio was able to sequence the region of interest and detect eight genetic variants, of which four are likely pathogenic. Furthermore, molecular modeling and dynamics of the RPGR Glu-Gly repeats binding to TTLL5 allowed for the structural evaluation of the variants, providing a way to predict their pathogenicity. Therefore, we propose PacBio sequencing as a standard procedure in diagnostic research for sequencing low-complexity regions such as RPGRORF15, aiding in the correct annotation of genetic variants in online databases.
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Affiliation(s)
- Gabriele Bonetti
- MAGI’s LAB, 38068 Rovereto, Italy; (M.C.M.); (M.B.)
- Department of Pharmaceutical Sciences, University of Perugia, 06123 Perugia, Italy
| | - William Cozza
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | - Andrea Bernini
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, 53100 Siena, Italy;
| | - Jurgen Kaftalli
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | - Chiara Mareso
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | | | | | - Leonardo Colombo
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, 20142 Milan, Italy; (L.C.); (S.M.)
| | - Salvatore Martella
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, 20142 Milan, Italy; (L.C.); (S.M.)
| | - Giovanni Staurenghi
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, 20157 Milan, Italy; (G.S.); (A.P.S.)
| | - Anna Paola Salvetti
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, 20157 Milan, Italy; (G.S.); (A.P.S.)
| | - Benedetto Falsini
- UOC Oculistica, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, Largo Gemelli 8, 00168 Rome, Italy (G.P.)
- Istituto di Oftalmologia, Università Cattolica del Sacro Cuore, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Giorgio Placidi
- UOC Oculistica, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, Largo Gemelli 8, 00168 Rome, Italy (G.P.)
| | - Marcella Attanasio
- Ospedale Sacrocuore Don Calabria, Viale Luigi Rizzardi, 4, 37024 Negrar di Valpolicella, Italy; (M.A.); (G.P.)
| | - Grazia Pertile
- Ospedale Sacrocuore Don Calabria, Viale Luigi Rizzardi, 4, 37024 Negrar di Valpolicella, Italy; (M.A.); (G.P.)
| | - Mario Bengala
- Medical Genetics Unit, Department of Oncohematology, Policlinico Tor Vergata, 00133 Rome, Italy;
| | - Francesca Bosello
- Department of Surgical Sciences, Dentistry, Paediatrics and Gynaecology, Section of Ophthalmology, University of Verona, 37134 Verona, Italy;
| | - Antonio Petracca
- Division of Medical Genetics, Fondazione IRCCS-Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy;
| | - Fabiana D’Esposito
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
- Imperial College Ophthalmic Research Group (ICORG) Unit, Imperial College, London NW1 5QH, UK
- Eye Clinic, Department of Neurosciences, Reproductive Sciences and Dentistry, University of Naples Federico II, 80138 Naples, Italy
| | - Benedetta Toschi
- Section of Medical Genetics, Department of Medical and Oncological Area, University Hospital of Pisa, 56126 Pisa, Italy;
| | - Paolo Lanzetta
- Department of Medicine-Ophthalmology, University of Udine, 33100 Udine, Italy;
- Istituto Europeo di Microchirurgia Oculare (IEMO), 33100 Udine, Italy
| | - Federico Ricci
- Department of Experimental Medicine, Tor Vergata University of Rome, Viale Oxford, 00133 Rome, Italy;
| | - Francesco Viola
- Department of Ophthalmology, Fondazione IRCCS Cà Granda, Clinica Regina Elena, 20122 Milan, Italy;
| | - Giuseppe Marceddu
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | - Matteo Bertelli
- MAGI’s LAB, 38068 Rovereto, Italy; (M.C.M.); (M.B.)
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
- MAGISNAT, Atlanta Tech Park, 107 Technology Parkway, Peachtree Corners, GA 30092, USA
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McKenna ED, Sarbanes SL, Cummings SW, Roll-Mecak A. The Tubulin Code, from Molecules to Health and Disease. Annu Rev Cell Dev Biol 2023; 39:331-361. [PMID: 37843925 DOI: 10.1146/annurev-cellbio-030123-032748] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Microtubules are essential dynamic polymers composed of α/β-tubulin heterodimers. They support intracellular trafficking, cell division, cellular motility, and other essential cellular processes. In many species, both α-tubulin and β-tubulin are encoded by multiple genes with distinct expression profiles and functionality. Microtubules are further diversified through abundant posttranslational modifications, which are added and removed by a suite of enzymes to form complex, stereotyped cellular arrays. The genetic and chemical diversity of tubulin constitute a tubulin code that regulates intrinsic microtubule properties and is read by cellular effectors, such as molecular motors and microtubule-associated proteins, to provide spatial and temporal specificity to microtubules in cells. In this review, we synthesize the rapidly expanding tubulin code literature and highlight limitations and opportunities for the field. As complex microtubule arrays underlie essential physiological processes, a better understanding of how cells employ the tubulin code has important implications for human disease ranging from cancer to neurological disorders.
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Affiliation(s)
- Elizabeth D McKenna
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA;
| | - Stephanie L Sarbanes
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA;
| | - Steven W Cummings
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA;
| | - Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA;
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA
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5
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Cehajic-Kapetanovic J, Martinez-Fernandez de la Camara C, Birtel J, Rehman S, McClements ME, Charbel Issa P, Lotery AJ, MacLaren RE. Impaired glutamylation of RPGR ORF15 underlies the cone-dominated phenotype associated with truncating distal ORF15 variants. Proc Natl Acad Sci U S A 2022; 119:e2208707119. [PMID: 36445968 PMCID: PMC9897430 DOI: 10.1073/pnas.2208707119] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Pathogenic variants in the Retinitis pigmentosa GTPase regulator (RPGR) gene lead to a clinically severe form of X-linked retinal dystrophy. However, it remains unclear why some variants cause a predominant rod, while others result in a cone-dominated phenotype. Post-translational glutamylation of the photoreceptor-specific RPGRORF15 isoform by the TTLL5 enzyme is essential for its optimal function in photoreceptors, and loss of TTLL5 leads to retinal dystrophy with a cone phenotype. Here we show that RPGR retinal disease, studied in a single cohort of 116 male patients, leads to a clear progressive shift from rod- to cone-dominating phenotype as the RPGRORF15 variant location approaches the distal part of the Open Reading Frame 15 (ORF15) region. The rod photoreceptor involvement on the contrary diminishes along the RGPR sequence, and the variants associated with the cone only phenotype are located predominantly in the very distal part, including the C-terminal basic domain. Moreover, these distal truncating RPGRORF15 variants disrupt the interaction with TTLL5 and lead to a significant impairment of RPGR glutamylation. Thus, consistent with the phenotype of TTLL5 pathogenic variants, our study shows that RPGRORF15 variants, which disrupt its basic domain and the interaction with TTLL5, also impair RPGR glutamylation and lead to the cone phenotype. This has implications for ongoing gene therapy clinical trials where the application of RPGR with impaired glutamylation may be less effective in treating RGPR dystrophies and may even convert a rod-cone dystrophy into a cone dystrophy phenotype.
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Affiliation(s)
- Jasmina Cehajic-Kapetanovic
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
- 2To whom correspondence may be addressed.
| | - Cristina Martinez-Fernandez de la Camara
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
- 2To whom correspondence may be addressed.
| | - Johannes Birtel
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
- cDepartment of Ophthalmology, University of Bonn, 53127Bonn, Germany
| | - Salwah Rehman
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
| | - Michelle E. McClements
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
| | - Peter Charbel Issa
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
| | - Andrew J Lotery
- dClinical Neurosciences Research Group, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, SO16 6YDSouthampton, United Kingdom
- eUniversity Hospital Southampton NHS Foundation Trust, SO16 6YDSouthampton, United Kingdom
| | - Robert E. MacLaren
- aNuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West WingOX3 9DU, United Kingdom
- bOxford Eye Hospital, Oxford University Hospitals The National Health Service Trust, John Radcliffe Hospital, West WingOX3 9DU, United Kingdom
- 2To whom correspondence may be addressed.
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Martinez-Fernandez de la Camara C, Cehajic-Kapetanovic J, MacLaren RE. Response: 'letter to the editor: emerging gene therapy products for RPGR-associated X-linked retinitis pigmentosa'. Expert Opin Emerg Drugs 2022; 27:449-450. [PMID: 36562394 DOI: 10.1080/14728214.2022.2152212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/10/2022] [Indexed: 12/24/2022]
Affiliation(s)
- Cristina Martinez-Fernandez de la Camara
- Department of Clinical Neurosciences, Nuffield Laboratory of Ophthalmology, University of Oxford, John Radcliffe Hospital, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Oxford, UK
| | - Jasmina Cehajic-Kapetanovic
- Department of Clinical Neurosciences, Nuffield Laboratory of Ophthalmology, University of Oxford, John Radcliffe Hospital, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Oxford, UK
| | - Robert E MacLaren
- Department of Clinical Neurosciences, Nuffield Laboratory of Ophthalmology, University of Oxford, John Radcliffe Hospital, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Oxford, UK
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7
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Poncet AF, Grunewald O, Vaclavik V, Meunier I, Drumare I, Pelletier V, Bocquet B, Todorova MG, Le Moing AG, Devos A, Schorderet DF, Jobic F, Defoort-Dhellemmes S, Dollfus H, Smirnov VM, Dhaenens CM. Contribution of Whole-Genome Sequencing and Transcript Analysis to Decipher Retinal Diseases Associated with MFSD8 Variants. Int J Mol Sci 2022; 23:ijms23084294. [PMID: 35457110 PMCID: PMC9032189 DOI: 10.3390/ijms23084294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/25/2022] [Accepted: 04/11/2022] [Indexed: 01/01/2023] Open
Abstract
Biallelic gene defects in MFSD8 are not only a cause of the late-infantile form of neuronal ceroid lipofuscinosis, but also of rare isolated retinal degeneration. We report clinical and genetic data of seven patients compound heterozygous or homozygous for variants in MFSD8, issued from a French cohort with inherited retinal degeneration, and two additional patients retrieved from a Swiss cohort. Next-generation sequencing of large panels combined with whole-genome sequencing allowed for the identification of twelve variants from which seven were novel. Among them were one deep intronic variant c.998+1669A>G, one large deletion encompassing exon 9 and 10, and a silent change c.750A>G. Transcript analysis performed on patients’ lymphoblastoid cell lines revealed the creation of a donor splice site by c.998+1669A>G, resulting in a 140 bp pseudoexon insertion in intron 10. Variant c.750A>G produced exon 8 skipping. In silico and in cellulo studies of these variants allowed us to assign the pathogenic effect, and showed that the combination of at least one severe variant with a moderate one leads to isolated retinal dystrophy, whereas the combination in trans of two severe variants is responsible for early onset severe retinal dystrophy in the context of late-infantile neuronal ceroid lipofuscinosis.
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Affiliation(s)
- Anaïs F. Poncet
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
| | - Olivier Grunewald
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
| | - Veronika Vaclavik
- University of Lausanne, Jules-Gonin Eye Hospital, 1004 Lausanne, Switzerland;
- Cantonal Hospital, Department of Ophthalmology, 1700 Fribourg, Switzerland
| | - Isabelle Meunier
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, Montpellier University Hospital, Sensgene Care Network, ERN-EYE Network, F-34000 Montpellier, France; (I.M.); (B.B.)
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, F-34000 Montpellier, France
| | - Isabelle Drumare
- Exploration de la Vision et Neuro-Ophtalmology, CHU de Lille, F-59000 Lille, France; (I.D.); (S.D.-D.); (V.M.S.)
| | - Valérie Pelletier
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologiques, Hopitaux Universitaires de Strasbourg, F-67000 Strasbourg, France; (V.P.); (H.D.)
| | - Béatrice Bocquet
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, Montpellier University Hospital, Sensgene Care Network, ERN-EYE Network, F-34000 Montpellier, France; (I.M.); (B.B.)
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, F-34000 Montpellier, France
| | - Margarita G. Todorova
- Department of Ophthalmology, Cantonal Hospital, 9007 St. Gallen, Switzerland;
- Department of Ophthalmology, University of Zürich, 8091 Zürich, Switzerland
- Department of Ophthalmology, University of Basel, 4056 Basel, Switzerland
| | - Anne-Gaëlle Le Moing
- Department of Child Neurology, Amiens-Picardy University Hospital, F-80000 Amiens, France;
| | - Aurore Devos
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
| | - Daniel F. Schorderet
- Faculty of Biology and Medicine, University of Lausanne and Faculty of Life Sciences, Ecole Polytechnique Fédérale of Lausanne, 1004 Lausanne, Switzerland;
| | - Florence Jobic
- Unité de Génétique Médicale et Oncogénétique, Centre Hospitalier Universitaire Amiens Picardie, F-80000 Amiens, France;
| | - Sabine Defoort-Dhellemmes
- Exploration de la Vision et Neuro-Ophtalmology, CHU de Lille, F-59000 Lille, France; (I.D.); (S.D.-D.); (V.M.S.)
| | - Hélène Dollfus
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologiques, Hopitaux Universitaires de Strasbourg, F-67000 Strasbourg, France; (V.P.); (H.D.)
| | - Vasily M. Smirnov
- Exploration de la Vision et Neuro-Ophtalmology, CHU de Lille, F-59000 Lille, France; (I.D.); (S.D.-D.); (V.M.S.)
- Université de Lille, Faculté de Médecine, F-59000 Lille, France
| | - Claire-Marie Dhaenens
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
- Correspondence: ; Tel.: +33-320444953
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Wang L, Sun L, Wan QH, Fang SG. Comparative Genomics Provides Insights into Adaptive Evolution in Tactile-Foraging Birds. Genes (Basel) 2022; 13:genes13040678. [PMID: 35456484 PMCID: PMC9028243 DOI: 10.3390/genes13040678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 11/28/2022] Open
Abstract
Tactile-foraging birds have evolved an enlarged principal sensory nucleus (PrV) but smaller brain regions related to the visual system, which reflects the difference in sensory dependence. The “trade-off” may exist between different senses in tactile foragers, as well as between corresponding sensory-processing areas in the brain. We explored the mechanism underlying the adaptive evolution of sensory systems in three tactile foragers (kiwi, mallard, and crested ibis). The results showed that olfaction-related genes in kiwi and mallard and hearing-related genes in crested ibis were expanded, indicating they may also have sensitive olfaction or hearing, respectively. However, some genes required for visual development were positively selected or had convergent amino acid substitutions in all three tactile branches, and it seems to show the possibility of visual degradation. In addition, we may provide a new visual-degradation candidate gene PDLIM1 who suffered dense convergent amino acid substitutions within the ZM domain. At last, two genes responsible for regulating the proliferation and differentiation of neuronal progenitor cells may play roles in determining the relative sizes of sensory areas in brain. This exploration offers insight into the relationship between specialized tactile-forging behavior and the evolution of sensory abilities and brain structures.
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Oh JK, Vargas Del Valle JG, Lima de Carvalho JR, Sun YJ, Levi SR, Ryu J, Yang J, Nagasaki T, Emanuelli A, Rasool N, Allikmets R, Sparrow JR, Izquierdo NJ, Duncan JL, Mahajan VB, Tsang SH. Expanding the phenotype of TTLL5-associated retinal dystrophy: a case series. Orphanet J Rare Dis 2022; 17:146. [PMID: 35365235 PMCID: PMC8973795 DOI: 10.1186/s13023-022-02295-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 03/21/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Inherited retinal dystrophies describe a heterogeneous group of retinal diseases that lead to the irreversible degeneration of rod and cone photoreceptors and eventual blindness. Recessive loss-of-function mutations in Tubulin Tyrosine Ligase Like 5 (TTLL5) represent a recently described cause of inherited cone-rod and cone dystrophy. This study describes the unusual phenotypes of three patients with autosomal recessive mutations in TTLL5. Examination of these patients included funduscopic evaluation, spectral-domain optical coherence tomography, short-wavelength autofluorescence, and full-field electroretinography (ffERG). Genetic diagnoses were confirmed using whole exome capture. Protein modeling of the identified variants was performed to explore potential genotype-phenotype correlations. RESULTS Genetic testing revealed five novel variants in TTLL5 in three unrelated patients with retinal dystrophy. Clinical imaging demonstrated features of sectoral cone-rod dystrophy and cone dystrophy, with phenotypic variability seen across all three patients. One patient also developed high-frequency hearing loss during a similar time period as the onset of retinal disease, potentially suggestive of a syndromic disorder. Retinal structure findings were corroborated with functional measures including ffERG findings that supported these diagnoses. Modeling of the five variants suggest that they cause different effects on protein function, providing a potential reason for genotype-phenotype correlation in these patients. CONCLUSIONS The authors report retinal phenotypic findings in three unrelated patients with novel mutations causing autosomal recessive TTLL5-mediated retinal dystrophy. These findings broaden the understanding of the phenotypes associated with TTLL5-mediated retinal disease and suggest that mutations in TTLL5 should be considered as a potential cause of sectoral retinal dystrophy in addition to cone-rod and cone dystrophies.
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Affiliation(s)
- Jin Kyun Oh
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
- State University of New York at Downstate Medical Center, Brooklyn, NY, USA
| | | | - Jose Ronaldo Lima de Carvalho
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Ophthalmology, Hospital das Clinicas de Pernambuco (HCPE) - Empresa Brasileira de Servicos Hospitalares (EBSERH), Federal University of Pernambuco (UFPE), Recife, Pernambuco, Brazil
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
| | - Young Joo Sun
- Omics Laboratory, Byers Eye Institute, Stanford University, Palo Alto, CA, USA
| | - Sarah R Levi
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
| | - Joseph Ryu
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
| | - Jing Yang
- Omics Laboratory, Byers Eye Institute, Stanford University, Palo Alto, CA, USA
| | - Takayuki Nagasaki
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
| | - Andres Emanuelli
- Department of Ophthalmology, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, USA
| | - Nailyn Rasool
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
| | - Rando Allikmets
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Pathology & Cell Biology, Columbia University Medical Center, New York, NY, USA
| | - Janet R Sparrow
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA
- Department of Pathology & Cell Biology, Columbia University Medical Center, New York, NY, USA
| | - Natalio J Izquierdo
- Department of Surgery, Medical Sciences Campus, University of Puerto Rico, San Juan, PR, USA
| | - Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
| | - Vinit B Mahajan
- Omics Laboratory, Byers Eye Institute, Stanford University, Palo Alto, CA, USA
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA
| | - Stephen H Tsang
- Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY, USA.
- Department of Pathology & Cell Biology, Columbia University Medical Center, New York, NY, USA.
- Harkness Eye Institute, Columbia University Medical Center, 635 West 165th Street, Box 212, New York, NY, 10032, USA.
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CRB1-Related Retinal Dystrophies in a Cohort of 50 Patients: A Reappraisal in the Light of Specific Müller Cell and Photoreceptor CRB1 Isoforms. Int J Mol Sci 2021; 22:ijms222312642. [PMID: 34884448 PMCID: PMC8657784 DOI: 10.3390/ijms222312642] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 01/29/2023] Open
Abstract
Pathogenic variants in CRB1 lead to diverse recessive retinal disorders from severe Leber congenital amaurosis to isolated macular dystrophy. Until recently, no clear phenotype-genotype correlation and no appropriate mouse models existed. Herein, we reappraise the phenotype-genotype correlation of 50 patients with regards to the recently identified CRB1 isoforms: a canonical long isoform A localized in Müller cells (12 exons) and a short isoform B predominant in photoreceptors (7 exons). Twenty-eight patients with early onset retinal dystrophy (EORD) consistently had a severe Müller impairment, with variable impact on the photoreceptors, regardless of isoform B expression. Among them, two patients expressing wild type isoform B carried one variant in exon 12, which specifically damaged intracellular protein interactions in Müller cells. Thirteen retinitis pigmentosa patients had mainly missense variants in laminin G-like domains and expressed at least 50% of isoform A. Eight patients with the c.498_506del variant had macular dystrophy. In one family homozygous for the c.1562C>T variant, the brother had EORD and the sister macular dystrophy. In contrast with the mouse model, these data highlight the key role of Müller cells in the severity of CRB1-related dystrophies in humans, which should be taken into consideration for future clinical trials.
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