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Kortuem FC, Kempf M, Merle DA, Kuehlewein L, Pohl L, Reith M, Jung R, Ott S, Stingl K, Stingl K. A morphometric analysis of the retinal arterioles with adaptive optics imaging in RPE65-associated retinal dystrophy after treatment with voretigene neparvovec. Acta Ophthalmol 2024; 102:e358-e366. [PMID: 37715554 DOI: 10.1111/aos.15765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/03/2023] [Accepted: 08/29/2023] [Indexed: 09/17/2023]
Abstract
PURPOSE To investigate the changes in retinal arterial architecture after treatment with voretigene neparvovec in patients with retinal dystrophy caused by bi-allelic mutations in the RPE65 gene. METHODS Sixteen eyes treated with voretigene neparvovec at the University Eye Clinic in Tuebingen, Germany, underwent adaptive optics ophthalmoscopy (AO) imaging at baseline and 2 weeks, 1, 3, 6 and 12 months after treatment. Follow-up was performed in six eyes of four patients. For each eye, five different positions at arterial vessels were selected and the wall-to-lumen ratio (WLR), the lumen diameter (LD) and the wall cross-sectional area (WCSA) were measured by the manufacturer's software over the observational period. RESULTS Vast retinal atrophy dominated all gained AO images. WLR fluctuated in the observation period without statistically significant change. LD and WCSA changed significantly after 2 weeks from the baseline examination and returned to values similar to baseline thereafter. There were no signs of inflammation such as macrophages or perivascular accumulated fluid visible. CONCLUSION AO imaging of the retinal vessels in RPE65-associated retinal dystrophies (IRD) is challenging. There was no change in the retinal arterial vasculature over the observation period of 12 months that would indicate inflammatory changes. Decrease of the LD and WCSA shortly after treatment might be caused by the perioperative prednisolone intake. AO of retinal vessels can be used as a diagnostic module to complement monitoring the disease and effects of genetic treatments if the acquisition is possible in selected cases.
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Affiliation(s)
- Friederike C Kortuem
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Melanie Kempf
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
| | - David A Merle
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Department of Ophthalmology, Medical University of Graz, Graz, Austria
| | - Laura Kuehlewein
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Lisa Pohl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Milda Reith
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Ronja Jung
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Saskia Ott
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Krunoslav Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
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Reith M, Stingl K, Kühlewein L, Kempf M, Stingl K, Langrova H. Comparison of Full-Field Stimulus Threshold Measurements in Patients With Retinitis Pigmentosa and Healthy Subjects With Dilated and Nondilated Pupil. Transl Vis Sci Technol 2024; 13:23. [PMID: 38630470 PMCID: PMC11033600 DOI: 10.1167/tvst.13.4.23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 03/06/2024] [Indexed: 04/19/2024] Open
Abstract
Purpose The common protocol of full-field stimulus threshold (FST) testing recommends pupil dilation. The aim of this study is to investigate the difference between FST measurements with dilated and nondilated pupils in healthy subjects and patients with retinitis pigmentosa (RP). Methods Twenty healthy subjects and 20 RP patients were selected. One pupil of each subject was dilated; the other eye was measured in physiological width of the pupil. The FST was conducted using Diagnosys Espion E2/E3 with white, blue, and red stimuli. Statistical analysis was conducted with a mixed-model analysis of variance and a paired t-test. Results The statistical analysis revealed a significant difference between measurements of dilated and nondilated pupils with the following: blue stimuli for all subjects and groups except those with highly progressed RP; white stimuli for all tested subjects in total, for RP patients with better-preserved visual field (VF), and rod-mediated FST response; and red stimuli for RP patients with better-preserved VF and rod-mediated FST response. On average, the difference between the FST values for RP patients were -3.2 ± 3 dB for blue, -2.3 ± 2.9 dB for white, and -0.83 ± 3 dB for red stimuli. The correlation between the FST values of dilated and nondilated pupils with all three stimuli was linear. Conclusions Current recommendations are to perform FST with dilated pupils. However, based on this study's findings, pupil dilation can be omitted for clinical diagnostics or rough follow-ups. Translational Relevance Our data provide useful information for the clinical use of FST.
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Affiliation(s)
- Milda Reith
- University Eye Hospital, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- University Eye Hospital, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
| | - Laura Kühlewein
- University Eye Hospital, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Melanie Kempf
- University Eye Hospital, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
| | - Krunoslav Stingl
- University Eye Hospital, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
| | - Hana Langrova
- Charles University, Medical Faculty in Hradec Kralove and Faculty Hospital, Department of Ophthalmology, Czech Republic
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Merle DA, Kohl S, Reith M, Schäferhoff K, Zuleger T, Stühn L, Stingl K, Kempf M, Kühlewein L, Grasshoff U, Stingl K. An Atypical Mild Phenotype of Autosomal Recessive RPE65-Associated Retinitis Pigmentosa. Klin Monbl Augenheilkd 2024; 241:266-271. [PMID: 38508215 DOI: 10.1055/a-2264-5480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Affiliation(s)
- David Adrian Merle
- Department of Ophthalmology, University Eye Hospital Tübingen, Germany
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
- Department of Ophthalmology, Medical University of Graz, Austria
| | - Susanne Kohl
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
| | - Milda Reith
- Department of Ophthalmology, University Eye Hospital Tübingen, Germany
| | - Karin Schäferhoff
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
| | - Theresia Zuleger
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
| | - Lara Stühn
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
| | - Krunoslav Stingl
- Department of Ophthalmology, University Eye Hospital Tübingen, Germany
- Center for Rare Eye Diseases, Eberhard Karls University of Tübingen, Germany
| | - Melanie Kempf
- Department of Ophthalmology, University Eye Hospital Tübingen, Germany
- Center for Rare Eye Diseases, Eberhard Karls University of Tübingen, Germany
| | - Laura Kühlewein
- Department of Ophthalmology, University Eye Hospital Tübingen, Germany
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
| | - Ute Grasshoff
- Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen, Germany
| | - Katarina Stingl
- Department of Ophthalmology, University Eye Hospital Tübingen, Germany
- Center for Rare Eye Diseases, Eberhard Karls University of Tübingen, Germany
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Weisschuh N, Mazzola P, Zuleger T, Schaeferhoff K, Kühlewein L, Kortüm F, Witt D, Liebmann A, Falb R, Pohl L, Reith M, Stühn LG, Bertrand M, Müller A, Casadei N, Kelemen O, Kelbsch C, Kernstock C, Richter P, Sadler F, Demidov G, Schütz L, Admard J, Sturm M, Grasshoff U, Tonagel F, Heinrich T, Nasser F, Wissinger B, Ossowski S, Kohl S, Riess O, Stingl K, Haack TB. Diagnostic genome sequencing improves diagnostic yield: a prospective single-centre study in 1000 patients with inherited eye diseases. J Med Genet 2024; 61:186-195. [PMID: 37734845 PMCID: PMC10850689 DOI: 10.1136/jmg-2023-109470] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 09/10/2023] [Indexed: 09/23/2023]
Abstract
PURPOSE Genome sequencing (GS) is expected to reduce the diagnostic gap in rare disease genetics. We aimed to evaluate a scalable framework for genome-based analyses 'beyond the exome' in regular care of patients with inherited retinal degeneration (IRD) or inherited optic neuropathy (ION). METHODS PCR-free short-read GS was performed on 1000 consecutive probands with IRD/ION in routine diagnostics. Complementary whole-blood RNA-sequencing (RNA-seq) was done in a subset of 74 patients. An open-source bioinformatics analysis pipeline was optimised for structural variant (SV) calling and combined RNA/DNA variation interpretation. RESULTS A definite genetic diagnosis was established in 57.4% of cases. For another 16.7%, variants of uncertain significance were identified in known IRD/ION genes, while the underlying genetic cause remained unresolved in 25.9%. SVs or alterations in non-coding genomic regions made up for 12.7% of the observed variants. The RNA-seq studies supported the classification of two unclear variants. CONCLUSION GS is feasible in clinical practice and reliably identifies causal variants in a substantial proportion of individuals. GS extends the diagnostic yield to rare non-coding variants and enables precise determination of SVs. The added diagnostic value of RNA-seq is limited by low expression levels of the major IRD disease genes in blood.
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Affiliation(s)
- Nicole Weisschuh
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Pascale Mazzola
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Theresia Zuleger
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Karin Schaeferhoff
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Laura Kühlewein
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Friederike Kortüm
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Dennis Witt
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Alexandra Liebmann
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Ruth Falb
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Lisa Pohl
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Milda Reith
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Lara G Stühn
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Miriam Bertrand
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Amelie Müller
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Nicolas Casadei
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Olga Kelemen
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Carina Kelbsch
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Christoph Kernstock
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Paul Richter
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Francoise Sadler
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - German Demidov
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Leon Schütz
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Jakob Admard
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Marc Sturm
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Ute Grasshoff
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Felix Tonagel
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Tilman Heinrich
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
- MVZ für Humangenetik und Molekularpathologie, Rostock, Germany
| | - Fadi Nasser
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Stephan Ossowski
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
- Institute for Bioinformatics and Medical Informatics (IBMI), University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Olaf Riess
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
- Center for Rare Disease, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
- Center for Rare Disease, University of Tübingen, Tübingen, Germany
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Kelbsch C, Kempf M, Jung R, Kortüm F, Reith M, Kuehlewein L, Kohl S, Strasser T, Peters T, Wilhelm H, Wilhelm B, Stingl K, Stingl K. Rod and Cone Function Measured Objectively by Chromatic Pupil Campimetry Show a Different Preservation Between Distinct Genotypes in Retinitis Pigmentosa. Invest Ophthalmol Vis Sci 2023; 64:18. [PMID: 37578425 PMCID: PMC10431211 DOI: 10.1167/iovs.64.11.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 07/10/2023] [Indexed: 08/15/2023] Open
Abstract
Purpose Verifying whether specific genotypes causing retinitis pigmentosa (RP) show differences in the preservation of rod and cone function measured by chromatic pupil campimetry (CPC). Methods Sixty-three RP eyes (37 male, 14-58 years) were measured using CPC with specific photopic and scotopic protocols, and the relative maximal constriction amplitudes and latencies to constriction onset were analyzed per genotype (RP due to variants in EYS, n = 14; PDE6A, n = 10; RPE65, n = 15; USH2A, n = 10; and RPGR, n = 14). Correlation analyses between the pupillary responses were performed with age, full-field stimulus threshold (FST), and optical coherence tomography (OCT) for cones and rods, respectively, to the genotype. Results Pupillary responses were most severely reduced in RPE65-RP. Patients with disease-associated variants in EYS and USH2A were accompanied with better-preserved rod function compared with the other subgroups, reaching statistical significance between EYS and RPE65. Cone function was statistically significantly correlated with age in USH2A-RP with an annual decline of 2.4%. Correlations of pupillary responses were found with FST but barely with the ellipsoid zone area in OCT. Latency was significantly more prolonged in RPE65-RP compared with the other genotypes for cones. Conclusions Rod and cone function measured objectively by CPC showed a different preservation between genotypes in RP. However, heterogeneity inside the same genotype was present. CPC data correlated with FST, but structural OCT parameters seem to be limited indicators for photoreceptor function in RP. Prolonged time dynamics for cones in RPE65 mutations suggest an impact on cone processing and might provide additional information in the evaluation of therapy effects.
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Affiliation(s)
- Carina Kelbsch
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Melanie Kempf
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Center for Rare Eye Diseases, University of Tuebingen, Tuebingen, Germany
| | - Ronja Jung
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Friederike Kortüm
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Milda Reith
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Laura Kuehlewein
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Torsten Strasser
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Tobias Peters
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Helmut Wilhelm
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Barbara Wilhelm
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
| | - Krunoslav Stingl
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Pupil Research Group at the Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Center for Rare Eye Diseases, University of Tuebingen, Tuebingen, Germany
| | - Katarina Stingl
- University Eye Hospital, Centre for Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Center for Rare Eye Diseases, University of Tuebingen, Tuebingen, Germany
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Priglinger CS, Rudolph G, Schmid I, Mazzola P, Haack TB, Reith M, Stingl K, Weisschuh N. Characterization of a novel non-canonical splice site variant (c.886-5T>A) in NBAS and description of the associated phenotype. Mol Genet Genomic Med 2023; 11:e2120. [PMID: 36479642 PMCID: PMC10009903 DOI: 10.1002/mgg3.2120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/28/2022] [Accepted: 11/29/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Biallelic pathogenic variants in the neuroblastoma-amplified sequence (NBAS) gene manifest in a broad spectrum of disorders, including, but not limited to recurrent acute liver failure, skeletal dysmorphism, susceptibility to infections, and SOPH syndrome with its cardinal symptoms of short stature, optic atrophy, and Pelger-Huët anomaly. We aimed to present clinical and genetic characteristics of two sisters (20 and 15 years old) who were diagnosed with optic atrophy and cone dystrophy in childhood. Genome sequencing revealed two novel variants in NBAS in compound heterozygous state in both sisters, namely a 1-bp deletion predicted to result in a premature termination codon (c.5104del; p.(Met1702*)), and a non-canonical splice site variant of unclear significance (c.886-5T>A; p.?). RESULTS Clinical examination and history revealed cone dystrophy, optic atrophy, and Pelger-Huët anomaly, but no short stature, recurrent acute liver failure, or susceptibility to infections. RNA analysis revealed that the c.886-5T>A variant results in two aberrant transcripts that are predicted to lead to in frame amino acid changes in the β-propeller region of the protein. CONCLUSION We hypothesize that the phenotype of our subjects, which appears to be at the end of the spectrum of NBAS-related disorders, could be explained by residual protein function mediated by the non-canonical splice site variant c.886-5T>A. Our study contributes to the existing knowledge on the genotypic and phenotypic spectrum of NBAS-related disorders.
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Affiliation(s)
- Claudia S Priglinger
- University Eye Hospital, Ludwig Maximilians University of Munich, Munich, Germany
| | - Günter Rudolph
- University Eye Hospital, Ludwig Maximilians University of Munich, Munich, Germany
| | - Irene Schmid
- Department of Pediatrics, Division of Pediatric Hematology and Oncology, Dr. von Hauner Children's Hospital, University Hospital, Ludwig Maximilian University of Munich, Munich, Germany
| | - Pascale Mazzola
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany.,Centre for Rare Diseases, University of Tübingen, Tübingen, Germany
| | - Milda Reith
- Centre for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- Centre for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Nicole Weisschuh
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
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Jung R, Kempf M, Pohl L, Kortüm F, Reith M, Kelbsch C, Kohl S, Wilhelm H, Wilhelm B, Stingl K, Stingl K. Frequency-dependent retinal responsiveness to sinusoidal electrical stimulation in achromatopsia. Exp Eye Res 2023; 226:109349. [PMID: 36516904 DOI: 10.1016/j.exer.2022.109349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/15/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022]
Abstract
Recently, we proposed a method to assess cell-specific retinal functions based on the frequency-dependent responses to sinusoidal transcorneal electrostimulation. In this study, we evaluated the alterations in responsiveness in achromatopsia patients to explore the frequency-selectivity of photoreceptors. The electrical stimulation was applied to one eye of genetically confirmed achromatopsia patients via corneal electrodes. The stimulus was composed of amplitude-modulated sine waves with variable carrier frequencies (4-30 Hz) and a steady low-frequency envelope. The retinal responsiveness across the spectrum was calculated based on the velocity and the synchronicity of the electrically evoked pupillary oscillations. Achromats displayed a characteristic peak in responsiveness in the 6-10 Hz range. In contrast, stimulus frequencies above 16 Hz elicited only weak pupil responses and weak phosphenes. Compared to the tuning curve of the healthy retina, responses to low-frequency stimulation appear to reflect mainly rod activation while higher frequencies seem to activate cones. The possibility to examine cell-specific retinal functions independently from their responses to light may improve our understanding of the structural changes in the retina induced by gene therapy.
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Affiliation(s)
- Ronja Jung
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany.
| | - Melanie Kempf
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany; Center for Rare Eye Diseases, University of Tuebingen, 72076, Tuebingen, Germany
| | - Lisa Pohl
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Friederike Kortüm
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Milda Reith
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Carina Kelbsch
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany; Pupil Research Group, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Helmut Wilhelm
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany; Pupil Research Group, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Barbara Wilhelm
- Pupil Research Group, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany
| | - Katarina Stingl
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany; Center for Rare Eye Diseases, University of Tuebingen, 72076, Tuebingen, Germany
| | - Krunoslav Stingl
- University Eye Hospital, Center for Ophthalmology, University of Tuebingen, 72076, Tuebingen, Germany; Center for Rare Eye Diseases, University of Tuebingen, 72076, Tuebingen, Germany
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Stingl K, Kempf M, Jung R, Kortüm F, Righetti G, Reith M, Dimopoulos S, Ott S, Kohl S, Stingl K. Therapy with voretigene neparvovec. How to measure success? Prog Retin Eye Res 2023; 92:101115. [PMID: 36096933 DOI: 10.1016/j.preteyeres.2022.101115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/17/2022] [Accepted: 08/19/2022] [Indexed: 02/01/2023]
Abstract
Retinal gene supplementation therapy such as the first approved one, voretigene neparvovec, delivers a functioning copy of the missing gene enabling the protein transcription in retinal cells and restore visual functions. After gene supplementation for the genetic defect, a complex network of functional regeneration is the consequence, whereas the extent is very individualized. Diagnostic and functional testings that have been used routinely by ophthalmologists so far to define the correct diagnosis, cannot be applied in the new context of defining small, sometimes subtle changes in visual functions. New view on retinal diagnostics is needed to understand this processes that define safety and efficacy of the treatment. Not only does vision have many aspects that must be addressed by specific evaluations and imaging techniques, but objective readouts of local retinal function for rods and cones separately have been an unmet need until recently. A reliable test-retest variability is necessary in rare diseases such as inherited retinal dystrophies, because statistics are often not applicable due to a low number of participants. Methods for a reliable individual evaluation of the therapy success are needed. In this manuscript we present an elaboration on retinal diagnostics combining psychophysics (eg. full-field stimulus threshold or dark adapted perimetry) as well as objective measures for local retinal function (eg. photopic and scotopic chromatic pupil campimetry) and retinal imaging for a meaningful workflow to apply in evaluation of the individual success in patients receiving gene therapy for photoreceptor diseases.
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Affiliation(s)
- Krunoslav Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany; Center for Rare Eye Diseases, University of Tuebingen, Tuebingen, Germany.
| | - Melanie Kempf
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany; Center for Rare Eye Diseases, University of Tuebingen, Tuebingen, Germany.
| | - Ronja Jung
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany.
| | - Friederike Kortüm
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany.
| | - Giulia Righetti
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany.
| | - Milda Reith
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany.
| | - Spyridon Dimopoulos
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany.
| | - Saskia Ott
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany.
| | - Susanne Kohl
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, Center for Ophthalmology, University of Tuebingen, Tuebingen, Germany.
| | - Katarina Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tuebingen, Tuebingen, Germany; Center for Rare Eye Diseases, University of Tuebingen, Tuebingen, Germany.
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9
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Abstract
There are several methods for local and general anesthesia in ophthalmological surgery that attempt to provide a stress and pain-free operating environment for both patient and surgeon. The decision-making depends on medical as well as on ophthalmological criteria and jointly falls to ophthalmologists and anesthesiologists. Topical and injective anesthesia (with or without conscious sedation) are generally methods of choice but general anesthesia can be preferable or mandatory in patients with particular internal diseases, children, emergencies and for extended surgical procedures. Pre-emptive analgesia before the operation is a meaningful complement in ophthalmological anesthesia.
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Affiliation(s)
- C-L Schönfeld
- Augenklinik Herzog Carl Theodor, Nymphenburger Str. 43, 80335, München, Deutschland.
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10
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Abstract
Flatfishes are a group of teleosts of high commercial and environmental interest, whose biology is still poorly understood. The recent rapid development of different 'omic' technologies is, however, enhancing the knowledge of the complex genetic control underlying different physiological processes of flatfishes. This review describes the different functional genomic approaches and resources currently available for flatfish research and summarizes different areas where microarray-based gene expression analysis has been applied. The increase in genome sequencing data has also allowed the construction of genetic linkage maps in different flatfish species; these maps are invaluable for investigating genome organization and identifying genetic traits of commercial interest. Despite the significant progress in this field, the genomic resources currently available for flatfish are still scarce. Further intensive research should be carried out to develop larger genomic sequence databases, high-density microarrays and, more detailed, complete linkage maps, using second-generation sequencing platforms. These tools will be crucial for further expanding the knowledge of flatfish physiology, and it is predicted that they will have important implications for wild fish population management, improved fish welfare and increased productivity in aquaculture.
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Affiliation(s)
- J Cerdà
- Laboratory of Institut de Recerca i Tecnologia Agroalimentàries (IRTA) - Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), Passeig marítim 37-49, 08003 Barcelona, Spain.
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11
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Reith M, Cattolico RA. Inverted repeat of Olisthodiscus luteus chloroplast DNA contains genes for both subunits of ribulose-1,5-bisphosphate carboxylase and the 32,000-dalton Q(B) protein: Phylogenetic implications. Proc Natl Acad Sci U S A 2010; 83:8599-603. [PMID: 16578794 PMCID: PMC386978 DOI: 10.1073/pnas.83.22.8599] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The chloroplast DNA of the chromophytic alga Olisthodiscus luteus has been physically mapped with four restriction enzymes. An inverted repeat of 22 kilobase pairs is present in this 150-kilobase-pair plastid genome. The inverted repeat contains the genes for the large and small subunit polypeptides of ribulose-1,5-bisphosphate carboxylase (EC 4.1.1.39) and also codes for the 32,000-dalton Q(B) protein. These observations demonstrate that significant differences exist in chloroplast genome structure and organization among major plant taxa.
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Affiliation(s)
- M Reith
- Botany Department, University of Washington, Seattle, WA 98195
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12
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Dacanay A, Knickle L, Solanky KS, Boyd JM, Walter JA, Brown LL, Johnson SC, Reith M. Contribution of the type III secretion system (TTSS) to virulence of Aeromonas salmonicida subsp. salmonicida. Microbiology (Reading) 2006; 152:1847-1856. [PMID: 16735747 DOI: 10.1099/mic.0.28768-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The recently described type III secretion system (TTSS) of Aeromonas salmonicida subsp. salmonicida has been linked to virulence in salmonids. In this study, three TTSS effector genes, aexT, aopH or aopO, were inactivated by deletion, as was ascC, the gene encoding the outer-membrane pore of the secretion apparatus. Effects on virulence were assayed by live challenge of Atlantic salmon (Salmo salar). The ΔascC mutant strain was avirulent by both intraperitoneal (i.p.) injection and immersion, did not appear to establish a clinically inapparent infection and did not confer protection from subsequent rechallenge with the parental strain. 1H NMR spectroscopy-based metabolite profiling of plasma from all fish showed significant differences in the metabolite profiles between the animals exposed to the parental strain or ΔascC. The experimental infection by immersion with ΔaopO was indistinguishable from that of the parental strain, that of ΔaexT was delayed, whilst the virulence of ΔaopH was reduced significantly but not abolished. By i.p. injection, ΔaexT, ΔaopH and ΔaopO caused an experimental disease indistinguishable from that of the parental strain. These data demonstrate that while the TTSS is absolutely essential for virulence of A. salmonicida subsp. salmonicida in Atlantic salmon, removal of individual effectors has little influence on virulence but has a significant effect on colonization. The ΔascC i.p. injection data also suggest that in addition to host invasion there is a second step in A. salmonicida pathogenesis that requires an active TTSS.
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Affiliation(s)
- A Dacanay
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - L Knickle
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - K S Solanky
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - J M Boyd
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - J A Walter
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - L L Brown
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - S C Johnson
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
| | - M Reith
- National Research Council of Canada Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, Canada
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13
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Dacanay A, Johnson SC, Bjornsdottir R, Ebanks RO, Ross NW, Reith M, Singh RK, Hiu J, Brown LL. Molecular characterization and quantitative analysis of superoxide dismutases in virulent and avirulent strains of Aeromonas salmonicida subsp. salmonicida. J Bacteriol 2003; 185:4336-44. [PMID: 12867441 PMCID: PMC165764 DOI: 10.1128/jb.185.15.4336-4344.2003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aeromonas salmonicida subsp. salmonicida is a facultatively intracellular gram-negative bacterium that is the etiological agent of furunculosis, a bacterial septicemia of salmonids that causes significant economic loss to the salmon farming industry. The mechanisms by which A. salmonicida evades intracellular killing may be relevant in understanding virulence and the eventual design of appropriate treatment strategies for furunculosis. We have identified two open reading frames (ORFs) and related upstream sequences that code for two putative superoxide dismutases (SODs), sodA and sodB. The sodA gene encoded a protein of 204 amino acids with a molecular mass of approximately 23.0 kDa (SodA) that had high similarity to other prokaryotic Mn-SODs. The sodB gene encoded a protein of 194 amino acids with a molecular mass of approximately 22.3 kDa that had high similarity to other prokaryotic Fe-SODs. Two enzymes with activities consistent with both these ORFs were identified by inhibition of O(2)(-)-catalyzed tetrazolium salt reduction in both gels and microtiter plate assays. The two enzymes differed in their expression patterns in in vivo- and in vitro-cultured bacteria. The regulatory sequences upstream of putative sodA were consistent with these differences. We could not identify other SOD isozymes such as sodC either functionally or through data mining. Levels of SOD were significantly higher in virulent than in avirulent strains of A. salmonicida subsp. salmonicida strain A449 when cultured in vitro and in vivo.
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Affiliation(s)
- A Dacanay
- Institute for Marine Biosciences, National Research Council, Halifax, Nova Scotia, Canada.
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14
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Lev EL, Daley KM, Conner NE, Reith M, Fernandez C, Owen SV. An intervention to increase quality of life and self-care self-efficacy and decrease symptoms in breast cancer patients. Sch Inq Nurs Pract 2002; 15:277-94. [PMID: 11871585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
This study tested effects of a nurse-administered self-efficacy intervention given on five monthly occasions and designed to enhance patients' self-care self-efficacy. The hypotheses were that at four months and eight months after beginning chemotherapy the efficacy-enhancing experimental group would have significantly higher scores on quality of life and self-care self-efficacy than the control group and significantly less symptom distress. Fifty-six women receiving chemotherapy for breast cancer were randomized to the experimental and control groups. Outcome variables were quality of life, measured by the Functional Assessment of Cancer Treatment-Breast (FACT-B), symptom distress, measured by the Symptom Distress Scale (SDS), and factors of self-care self-efficacy, measured by Strategies Used by Patients to Promote Health (SUPPH). The interaction effects for the FACT-B ranged from small for functional concerns (eta square = .03) to large for social concerns (eta square = .110); effects for the SDS were large (eta square = .140), and for factors on the SUPPH effect sizes ranged from small (eta square = .01) for Enjoying Life and Stress Reduction to medium (eta square = .089) for Coping, and large (eta square = .141) for Making Decisions. Interventions to promote self-efficacy may increase quality of life and decrease symptom distress for women diagnosed with breast cancer.
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Affiliation(s)
- E L Lev
- Rutgers, College of Nursing, Newark, NJ 07102, USA
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15
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Douglas S, Zauner S, Fraunholz M, Beaton M, Penny S, Deng LT, Wu X, Reith M, Cavalier-Smith T, Maier UG. The highly reduced genome of an enslaved algal nucleus. Nature 2001; 410:1091-6. [PMID: 11323671 DOI: 10.1038/35074092] [Citation(s) in RCA: 280] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chromophyte algae differ fundamentally from plants in possessing chloroplasts that contain chlorophyll c and that have a more complex bounding-membrane topology. Although chromophytes are known to be evolutionary chimaeras of a red alga and a non-photosynthetic host, which gave rise to their exceptional membrane complexity, their cell biology is poorly understood. Cryptomonads are the only chromophytes that still retain the enslaved red algal nucleus as a minute nucleomorph. Here we report complete sequences for all three nucleomorph chromosomes from the cryptomonad Guillardia theta. This tiny 551-kilobase eukaryotic genome is the most gene-dense known, with only 17 diminutive spliceosomal introns and 44 overlapping genes. Marked evolutionary compaction hundreds of millions of years ago eliminated nearly all the nucleomorph genes for metabolic functions, but left 30 for chloroplast-located proteins. To allow expression of these proteins, nucleomorphs retain hundreds of genetic-housekeeping genes. Nucleomorph DNA replication and periplastid protein synthesis require the import of many nuclear gene products across endoplasmic reticulum and periplastid membranes. The chromosomes have centromeres, but possibly only one loop domain, offering a means for studying eukaryotic chromosome replication, segregation and evolution.
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Affiliation(s)
- S Douglas
- National Research Council of Canada Institute for Marine Biosciences and Program in Evolutionary Biology, Canadian Institute of Advanced Research, 1411 Oxford Street, Halifax, Nova Scotia B3H 3ZI, Canada
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16
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Reith M, Munholland J, Kelly J, Finn RN, Fyhn HJ. Lipovitellins derived from two forms of vitellogenin are differentially processed during oocyte maturation in haddock (Melanogrammus aeglefinus). J Exp Zool 2001; 291:58-67. [PMID: 11335916 DOI: 10.1002/jez.5] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In the process of cloning vitellogenin (Vtg) cDNAs from haddock (Melanogrammus aeglefinus), two related, but distinct, mRNAs were identified. Full-length cDNA sequences were determined for both Vtg types (Had1 and Had2), and the deduced amino acid sequences were found to be 54% identical to each other and 48-58% identical to other teleost Vtgs. To investigate the expression of the two Vtg mRNAs, proteins from prehydrated oocytes and fertilized eggs were separated on SDS-polyacrylamide gels. Only a single lipovitellin I band was detected in each sample, and the egg lipovitellin I was smaller (97 vs. 110 kDa) than the oocyte protein, indicative of proteolytic processing during oocyte hydration. Mass spectrometric (MALDI-TOFMS and tandem mass spectrometry) analyses of tryptic fragments from the haddock oocyte and egg lipovitellin I revealed that the lipovitellin I from prehydrated oocytes contained tryptic fragments that matched the sequences of both types of Vtg, suggesting that there were two proteins in this band, while the egg lipovitellin I contained tryptic fragments that only matched the Had1 cDNA sequence, indicating that the Had2 lipovitellin had been degraded during hydration. Physiological data from haddock oocytes and eggs demonstrate that, as in other marine fish that spawn pelagic eggs, the free amino acid content increases during oocyte hydration and apparently contributes to hydration by driving the osmotic uptake of water. The correlation of the disappearance of one lipovitellin I with the increase of free amino acids in the oocyte suggests that this protein is a major source of the free amino acids for oocyte hydration.
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Affiliation(s)
- M Reith
- NRC Institute for Marine Biosciences, Halifax, Nova Scotia B3H 3Z1, Canada.
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17
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Affiliation(s)
- M Reith
- South Wales Forensic Psychiatric Service, Caswell Clinic, Glanrhyd Hospital, Bridgend
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18
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Burger G, Lang BF, Reith M, Gray MW. Genes encoding the same three subunits of respiratory complex II are present in the mitochondrial DNA of two phylogenetically distant eukaryotes. Proc Natl Acad Sci U S A 1996; 93:2328-32. [PMID: 8637872 PMCID: PMC39795 DOI: 10.1073/pnas.93.6.2328] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Although mitochondrial DNA is known to encode a limited number (<20) of the polypeptide components of respiratory complexes I, III, IV, and V, genes for components of complex II [succinate dehydrogenase (ubiquinone); succinate:ubiquinone oxidoreductase, EC 1.3.5.1] are conspicuously lacking in mitochondrial genomes so far characterized. Here we show that the same three subunits of complex II are encoded in the mitochondrial DNA of two phylogenetically distant eukaryotes, Porphyra purpurea (a photosynthetic red alga) and Reclinomonas americana (a heterotrophic zooflagellate). These complex II genes, sdh2, sdh3, and sdh4, are homologs, respectively, of Escherichia coli sdhB, sdhC, and sdhD. In E. coli, sdhB encodes the iron-sulfur subunit of succinate dehydrogenase (SDH), whereas sdhC and sdhD specify, respectively, apocytochrome b558 and a hydrophobic 13-kDa polypeptide, which together anchor SDH to the inner mitochondrial membrane. Amino acid sequence similarities indicate that sdh2, sdh3, and sdh4 were originally encoded in the protomitochondrial genome and have subsequently been transferred to the nuclear genome in most eukaryotes. The data presented here are consistent with the view that mitochondria constitute a monophyletic lineage.
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Affiliation(s)
- G Burger
- Program in Evolutionary Biology, Canadian Institute for Advanced Research, Département de Biochimie, Université de Montréal, Quebec, Canada
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19
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Schu P, Reith M. Evaluation of different preparation parameters for the production and cryopreservation of seed cultures with recombinant Saccharomyces cerevisae. Cryobiology 1995; 32:379-88. [PMID: 7656571 DOI: 10.1006/cryo.1995.1038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In this article we describe the intensive investigation of defined physicochemical parameters for their influence on the preparation, storage stability in liquid nitrogen, and the post-thaw productivity of a recombinant strain of Saccharomyces cerevisiae expressing the human factor XIIIa protein. Preparation of industrially sized seed cultures and their storage stability were monitored over more than a 1-year period. Major parameters recorded before and after thawing were number of colony-forming units on agar slant media, plasmid retention, and expression capacity of the recombinant protein. The viability of the cells after reconstitution of the frozen batches was found to improve significantly if a certain combination of prethaw growth conditions was applied and amino acids were included in the cryoprotectant media. In addition, the influence of different concentrations of glycerol as a cryoprotectant was investigated and the specific freezing conditions which improved the viability were identified. Even without complex freezing devices for the controlled freezing of cultures, viability rates of 85% and higher were obtained, enabling consistent production of the recombinant protein.
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Affiliation(s)
- P Schu
- Research Laboratories of Behringwerke AG, Marburg, Federal Republic of Germany
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20
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Abstract
Recent information on the plastid genes and genomes of rhodophyte (red algae) and chromophyte (yellow and brown algae) plastids are summarized. The plastid genomes of these algae contain many more genes than those of metaphyte (land plant) plastids, and the encoded proteins are involved in a much wider range of metabolic activities. Rhodophyte and chromophyte plastid genomes contain very few introns and maintain many ancestral gene operons, which suggests that they are more primitive than those of metaphytes. Hypotheses of plastid evolution (monophyletic or polyphyletic primary origins) are discussed and assessed. The data available at present support the idea that all plastids arose from a single endosymbiotic event that involved a cyanobacterium and a eukaryote host (monophyletic origin). Information from rhodophyte and chromophyte plastid genomes also provides insights into the evolution of other organisms. Finally, the implications for plastid metabolism that arise from the presence of several genes on rhodophyte and chromophyte plastid genomes are discussed.
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Affiliation(s)
- M. Reith
- Marine Biology Section, NRC Institute for Marine Biosciences, Halifax, Nova Scotia B3H 3Z1, Canada
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21
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Abstract
The influence of metaphit, a phencyclidine derivative, on the amplitude of Long-Term Potentiation (LTP) in the mouse hippocampus was investigated. Mice (C57BL/6) of both sexes were injected with metaphit (80 mg/kg) and hippocampal slices were prepared at 3, 24, 48 hrs and 6 days following injection. The extracellular evoked potentials were recorded from the pyramidal cell layer following Schaffer collateral stimulation. The threshold value, defined as the minimum strength of the stimuli to evoke a 0.1 mV potential, was about 5 fold greater in metaphit slices than in control slices 3 hr following injection, and then declined to the control value within 6 days. The magnitude of LTP was also amplified by metaphit in a time-dependent fashion. The effect was visible three hours after injection, reached its maximum at 48 hr and then declined to a level slightly higher than control at 6 days following injection. These results demonstrate that metaphit, a compound known to induce audiogenic seizures, is able to modify synaptic plasticity in the hippocampus. Presented results are also in agreement with our previous data which demonstrated an interaction between the mechanisms of LTP and audiogenic seizure.
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Affiliation(s)
- R Albanese
- CSI/IBR Center for Developmental Neuroscience, College of Staten Island, NY 10314
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22
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Reith M, Munholland J. The ribosomal RNA repeats are non-identical and directly oriented in the chloroplast genome of the red alga Porphyra purpurea. Curr Genet 1993; 24:443-50. [PMID: 8299161 DOI: 10.1007/bf00351855] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A detailed restriction map of the chloroplast genome of the red alga Porphyra purpurea has been constructed. Southern hybridization experiments with cloned or gel-purified restriction fragments and PCR products indicate that the P. purpurea chloroplast genome is approximately 188 kb in size. This circular molecule contains two rRNA-encoding repeats (approximately 4.9 kb) that separate the genome into single-copy regions of 34 kb and 144 kb. Interestingly, these repeats are arranged in a direct orientation. In addition, DNA sequencing of the ends of both repeats revealed that the two rRNA repeats are not identical. No intramolecular recombination between the repeats can be detected. We discuss the possibility that the chloroplast genome of P. purpurea is organized like that of the ancestral chloroplast.
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Affiliation(s)
- M Reith
- National Research Council of Canada, Institute for Marine Biosciences, Halifax, Nova Scotia
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23
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Abstract
Extensive DNA sequencing of the chloroplast genome of the red alga Porphyra purpurea has resulted in the detection of more than 125 genes. Fifty-eight (approximately 46%) of these genes are not found on the chloroplast genomes of land plants. These include genes encoding 17 photosynthetic proteins, three tRNAs, and nine ribosomal proteins. In addition, nine genes encoding proteins related to biosynthetic functions, six genes encoding proteins involved in gene expression, and at least five genes encoding miscellaneous proteins are among those not known to be located on land plant chloroplast genomes. The increased coding capacity of the P. purpurea chloroplast genome, along with other characteristics such as the absence of introns and the conservation of ancestral operons, demonstrate the primitive nature of the P. purpurea chloroplast genome. In addition, evidence for a monophyletic origin of chloroplasts is suggested by the identification of two groups of genes that are clustered in chloroplast genomes but not in cyanobacteria.
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Affiliation(s)
- M. Reith
- National Research Council of Canada, Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia, B3H 3Z1 Canada
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24
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Abstract
To isolate the gene encoding the amino-acid biosynthetic enzyme acetolactate synthase (ALS) from the red alga Porphyra umbilicalis, PCR experiments were carried out using P. umbilicalis DNA as the template and degenerate oligonucleotides representing conserved regions of ALS amino-acid sequences. Interestingly, the PCR product (0.9 kb) hybridized exclusively to the plastid DNA of this red alga. DNA sequencing of two contiguous EcoRI plastid DNA clones revealed a 590 amino-acid open reading frame with 55 to 61% identity to cyanobacterial ALS sequences. A second gene (argB) encoding another amino-acid biosynthetic enzyme, N-acetylglutamate kinase, was identified upstream of, and on the opposite strand to the gene encoding ALS (ilvB). This is the first molecular characterization of a gene for an arginine biosynthetic enzyme from any plant. In addition, two tRNA genes, trnT(GGU) and trnY(GUA), were detected downstream from ilvB while four tRNA genes, trnfM(CAU), trnA(GGC), trnA(GGC), trnS(-GCU) and trnD(GUC), were found downstream from argB. trnA(GGC) is not found in the chloroplast genomes of land plants.
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Affiliation(s)
- M Reith
- National Research Council of Canada, Institute for Marine Biosciences, Halifax, Nova Scotia
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25
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Reith M. A beta-ketoacyl-acyl carrier protein synthase III gene (fabH) is encoded on the chloroplast genome of the red alga Porphyra umbilicalis. Plant Mol Biol 1993; 21:185-189. [PMID: 8425047 DOI: 10.1007/bf00039630] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
DNA sequencing of a region of the chloroplast genome of the red alga Porphyra umbilicalis revealed an open reading frame of 326 amino acids. Databank searches indicated that this ORF is 34% identical to an E. coli gene (fabH) encoding beta-ketoacyl-carrier protein synthase III. In addition, a leucine tRNA gene (trnL(GAG)) was detected just downstream. Neither of these genes are encoded on the chloroplast genomes of land plants.
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Affiliation(s)
- M Reith
- National Research Council of Canada, Institute for Marine Biosciences, Halifax, Nova Scotia
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26
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Abstract
A PCR experiment using Porphyra umbilicalis DNA as the template and degenerate oligonucleotides representing conserved regions of hsp70 amino acid sequences generated a 1 kb product that hybridized exclusively to the plastid DNA of this red alga. DNA sequencing of two contiguous EcoRI plastid DNA clones revealed a 620 amino acid open reading frame with 71% identity to the dnaK gene of the cyanobacterium, Synechocystis 6803. Northern hybridization experiments detected a 2.3 kb transcript that is present in control (15 degrees C) cultures and increases approximately 7-fold upon heat shock (75 minutes at 30 degrees C).
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Affiliation(s)
- M Reith
- Institute for Marine Biosciences, National Research Council of Canada, Nova Scotia
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27
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28
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Reith M, Straus NA. Nucleotide sequence of the chloroplast gene responsible for triazine resistance in canola. Theor Appl Genet 1987; 73:357-363. [PMID: 24240995 DOI: 10.1007/bf00262501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/1986] [Accepted: 07/25/1986] [Indexed: 05/28/2023]
Abstract
The nucleotide sequence for the psbA gene from a triazine resistant cultivar of B. napus (cv 'Triton') has been determined. This gene encodes an open reading frame of 353 amino acids that is highly homologous to other higher plant psbA genes at both the nucleotide and amino acid levels. As has been found for other triazine resistant psbA genes, the 'Triton' psbA contains an A to G nucleotide change which results in a serine to glycine amino acid substitution at position 264. The B. napus psbA gene also has a G insertion at position -9 resulting in a ribosome binding site sequence (AGGA) just before the initial methionine and suggesting that the entire open reading frame is translated. A large (72 bp) insertion is also found upstream of the B. napus psbA gene which resembles a similar insertion in the mustard psbA. The "uncloneable" nature of the entire gene is further investigated through reconstruction experiments and the implications discussed.
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Affiliation(s)
- M Reith
- Department of Botany, University of Toronto, M5S 1A1, Toronto, Ontario, Canada
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Xiao W, Reith M, Erickson LR, Williams JP, Straus NA. Mapping the chloroplast genome of triazine resistant canola. Theor Appl Genet 1986; 71:716-723. [PMID: 24247607 DOI: 10.1007/bf00263269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/12/1985] [Indexed: 06/02/2023]
Abstract
The chloroplast of a triazine resistant weed biotype of Brassica campestris (bird's rape) has been transferred by repeated back-crossing into an agriculturally important strain, 'Tower', of Brassica napus to form a triazine resistant cultivar of canola, 'Triton', that is low in both erucic acid and thioglucosinolate. In this report, the B. campestris derived chloroplast chromosome of B. napus (cv 'Triton') has been cloned into bacterial plasmids and physically mapped for eight restriction enzymes: Apa I, Bam HI, BglI, Hind III, Pst I, Pvu II, Sac I and Xho I. The genes for rRNA, rbcL, cytF, atpA, atpB, atpE, atpH and the triazine resistance gene, psbA were located on the map by heterologous hybridization. The directions of transcription for most of these genes were determined by reverse heterologous hybridization.
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Affiliation(s)
- W Xiao
- Department of Botany, University of Toronto, 6 Queen's Park Cresent, M5S 1A1, Toronto, Ontario, Canada
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