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Gnaiger E. Complex II ambiguities-FADH 2 in the electron transfer system. J Biol Chem 2024; 300:105470. [PMID: 38118236 PMCID: PMC10772739 DOI: 10.1016/j.jbc.2023.105470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 11/01/2023] [Accepted: 11/06/2023] [Indexed: 12/22/2023] Open
Abstract
The prevailing notion that reduced cofactors NADH and FADH2 transfer electrons from the tricarboxylic acid cycle to the mitochondrial electron transfer system creates ambiguities regarding respiratory Complex II (CII). CII is the only membrane-bound enzyme in the tricarboxylic acid cycle and is part of the electron transfer system of the mitochondrial inner membrane feeding electrons into the coenzyme Q-junction. The succinate dehydrogenase subunit SDHA of CII oxidizes succinate and reduces the covalently bound prosthetic group FAD to FADH2 in the canonical forward tricarboxylic acid cycle. However, several graphical representations of the electron transfer system depict FADH2 in the mitochondrial matrix as a substrate to be oxidized by CII. This leads to the false conclusion that FADH2 from the β-oxidation cycle in fatty acid oxidation feeds electrons into CII. In reality, dehydrogenases of fatty acid oxidation channel electrons to the Q-junction but not through CII. The ambiguities surrounding Complex II in the literature and educational resources call for quality control, to secure scientific standards in current communications of bioenergetics, and ultimately support adequate clinical applications. This review aims to raise awareness of the inherent ambiguity crisis, complementing efforts to address the well-acknowledged issues of credibility and reproducibility.
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Araya J, Araya C, Conrads T, Sadun A, Seleme N. Leber Hereditary Optic Neuropathy Conversion in a Patient With Idiopathic Intracranial Hypertension. J Neuroophthalmol 2023; 43:e139-e141. [PMID: 36730072 DOI: 10.1097/wno.0000000000001572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Javiera Araya
- Neuro Ophthalmology Unit (JA, CA, NS), Department of Ophthalmology, Hospital Clínico Universidad de Chile, Santiago de Chile, Chile; Critical Care Unit (TC), Hospital Clínico Universidad de Chile, Santiago de Chile, Chile; and Neuro Ophthalmology Unit (AS), Doheny Eye Center, UCLA, Pasadena, Los Angeles
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Chen BS, Harvey JP, Gilhooley MJ, Jurkute N, Yu-Wai-Man P. Mitochondria and the eye-manifestations of mitochondrial diseases and their management. Eye (Lond) 2023; 37:2416-2425. [PMID: 37185957 PMCID: PMC10397317 DOI: 10.1038/s41433-023-02523-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 01/31/2023] [Accepted: 04/04/2023] [Indexed: 05/17/2023] Open
Abstract
Historically, distinct mitochondrial syndromes were recognised clinically by their ocular features. Due to their predilection for metabolically active tissue, mitochondrial diseases frequently involve the eye, resulting in a range of ophthalmic manifestations including progressive external ophthalmoplegia, retinopathy and optic neuropathy, as well as deficiencies of the retrochiasmal visual pathway. With the wider availability of genetic testing in clinical practice, it is now recognised that genotype-phenotype correlations in mitochondrial diseases can be imprecise: many classic syndromes can be associated with multiple genes and genetic variants, and the same genetic variant can have multiple clinical presentations, including subclinical ophthalmic manifestations in individuals who are otherwise asymptomatic. Previously considered rare diseases with no effective treatments, considerable progress has been made in our understanding of mitochondrial diseases with new therapies emerging, in particular, gene therapy for inherited optic neuropathies.
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Affiliation(s)
- Benson S Chen
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK
| | - Joshua P Harvey
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Institute of Ophthalmology, University College London, London, UK
| | - Michael J Gilhooley
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Institute of Ophthalmology, University College London, London, UK
- The National Hospital for Neurology and Neurosurgery, Queen Square, University College London Hospitals NHS Foundation Trust, London, UK
| | - Neringa Jurkute
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Institute of Ophthalmology, University College London, London, UK
- The National Hospital for Neurology and Neurosurgery, Queen Square, University College London Hospitals NHS Foundation Trust, London, UK
| | - Patrick Yu-Wai-Man
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK.
- Moorfields Eye Hospital NHS Foundation Trust, London, UK.
- Institute of Ophthalmology, University College London, London, UK.
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Chen BS, Yu-Wai-Man P, Newman NJ. Developments in the Treatment of Leber Hereditary Optic Neuropathy. Curr Neurol Neurosci Rep 2022; 22:881-892. [PMID: 36414808 PMCID: PMC9750907 DOI: 10.1007/s11910-022-01246-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2022] [Indexed: 11/24/2022]
Abstract
PURPOSEOF REVIEW To outline the current landscape of treatments for Leber hereditary optic neuropathy (LHON) along the therapeutic delivery pipeline, exploring the mechanisms of action and evidence for these therapeutic approaches. RECENT FINDINGS Treatments for LHON can be broadly classified as either mutation-specific or mutation-independent. Mutation-specific therapies aim to correct the underlying mutation through the use of a gene-editing platform or replace the faulty mitochondrial DNA-encoded protein by delivering the wild-type gene using a suitable vector. Recent gene therapy clinical trials assessing the efficacy of allotopically expressed MT-ND4 for the treatment of LHON due to the m.11778G > A mutation in MT-ND4 have shown positive results when treated within 12 months of symptom onset. Mutation-independent therapies can have various downstream targets that aim to improve mitochondrial respiration, reduce mitochondrial stress, inhibit or delay retinal ganglion cell apoptosis, and/or promote retinal ganglion cell survival. Idebenone, a synthetic hydrosoluble analogue of co-enzyme Q10 (ubiquinone), is the only approved treatment for LHON. Mutation-independent approaches to gene therapy under pre-clinical investigation for other neurodegenerative disorders may have the potential to benefit patients with LHON. Although approved treatments are presently limited, innovations in gene therapy and editing are driving the expansion of the therapeutic delivery pipeline for LHON.
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Affiliation(s)
- Benson S Chen
- John Van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, UK.
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK.
| | - Patrick Yu-Wai-Man
- John Van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, UK
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Institute of Ophthalmology, University College London, London, UK
| | - Nancy J Newman
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
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6
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Yin Y, Shen H. Common methods in mitochondrial research (Review). Int J Mol Med 2022; 50:126. [PMID: 36004457 PMCID: PMC9448300 DOI: 10.3892/ijmm.2022.5182] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 08/09/2022] [Indexed: 01/18/2023] Open
Affiliation(s)
- Yiyuan Yin
- Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Haitao Shen
- Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
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Zibold J, von Livonius B, Kolarova H, Rudolph G, Priglinger CS, Klopstock T, Catarino CB. Vitamin B12 in Leber hereditary optic neuropathy mutation carriers: a prospective cohort study. Orphanet J Rare Dis 2022; 17:310. [PMID: 35945620 PMCID: PMC9361590 DOI: 10.1186/s13023-022-02453-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 07/17/2022] [Indexed: 11/10/2022] Open
Abstract
Background Leber hereditary optic neuropathy (LHON) is the most common mitochondrial disorder, frequently resulting in acute or subacute severe bilateral central vision loss. Vitamin B12 deficiency is also a known cause of optic neuropathy through mitochondrial dysfunction. Here we evaluated the prevalence and clinical significance of vitamin B12 deficiency in a large cohort of LHON patients and asymptomatic mutation carriers from a tertiary referral center. Methods From the Munich LHON prospective cohort study, participants included all LHON patients and asymptomatic LHON mutation carriers, who were recruited between February 2014 and March 2020 and consented to participate. Neurological, general, and ophthalmological examinations were regularly performed, as were laboratory tests. Vitamin B12 deficiency was diagnosed if serum vitamin B12 was below 201 pg/mL, or if 201–339 pg/mL plus low serum holotranscobalamin or elevated serum methylmalonic acid or elevated total plasma homocysteine. Results We analyzed 244 subjects, including 147 symptomatic LHON patients (74% males) and 97 asymptomatic mutation carriers (31% males). Median age at study baseline was 34 years (range 5–82 years). The prevalence of vitamin B12 deficiency was higher for LHON mutation carriers than for the general population in all age categories. This was statistically significant for the LHON mutation carriers under 65 years (21% vs. 5–7%, p = 0.002). While vitamin B12 deficiency prevalence was not statistically different between LHON patients and asymptomatic mutation carriers, its clinical correlates, e.g., macrocytosis and polyneuropathy, were more frequent in the subgroup of LHON patients. Excessive alcohol consumption was a significant predictor of vitamin B12 deficiency (p < 0.05). Conclusions The high prevalence of vitamin B12 deficiency in LHON mutation carriers, both asymptomatic mutation carriers and LHON patients, highlights the need for regular vitamin B12 screening in this population, in order to ensure early treatment, aiming for better outcomes. Our study is not conclusive regarding vitamin B12 deficiency as determinant for disease conversion in LHON, and further research is warranted to disentangle the role of vitamin B12 in the pathophysiology and prognosis of LHON.
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Affiliation(s)
- Julia Zibold
- Department of Neurology, Friedrich-Baur Institute, University Hospital, Ludwig-Maximilian University (LMU) Munich, Ziemssenstr. 1a, 80336, Munich, Germany
| | - Bettina von Livonius
- Department of Ophthalmology, University Hospital, Ludwig-Maximilian University (LMU) Munich, Munich, Germany
| | - Hana Kolarova
- Department of Neurology, Friedrich-Baur Institute, University Hospital, Ludwig-Maximilian University (LMU) Munich, Ziemssenstr. 1a, 80336, Munich, Germany.,Department of Pediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Günter Rudolph
- Department of Ophthalmology, University Hospital, Ludwig-Maximilian University (LMU) Munich, Munich, Germany
| | - Claudia S Priglinger
- Department of Ophthalmology, University Hospital, Ludwig-Maximilian University (LMU) Munich, Munich, Germany
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur Institute, University Hospital, Ludwig-Maximilian University (LMU) Munich, Ziemssenstr. 1a, 80336, Munich, Germany.,German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Claudia B Catarino
- Department of Neurology, Friedrich-Baur Institute, University Hospital, Ludwig-Maximilian University (LMU) Munich, Ziemssenstr. 1a, 80336, Munich, Germany.
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Chen BS, Yu-Wai-Man P. From Bench to Bedside-Delivering Gene Therapy for Leber Hereditary Optic Neuropathy. Cold Spring Harb Perspect Med 2022; 12:a041282. [PMID: 35863905 PMCID: PMC9310952 DOI: 10.1101/cshperspect.a041282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Leber hereditary optic neuropathy (LHON) is a rare, maternally inherited mitochondrial disorder that presents with severe bilateral sequential vision loss, due to the selective degeneration of retinal ganglion cells (RGCs). Since the mitochondrial genetic basis for LHON was uncovered in 1988, considerable progress has been made in understanding the pathogenetic mechanisms driving RGC loss, which has enabled the development of therapeutic approaches aimed at mitigating the underlying mitochondrial dysfunction. In this review, we explore the genetics of LHON, from bench to bedside, focusing on the pathogenetic mechanisms and how these have informed the development of different gene therapy approaches, in particular the technique of allotopic expression with adeno-associated viral vectors. Finally, we provide an overview of the recent gene therapy clinical trials and consider the unanswered questions, challenges, and future prospects.
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Affiliation(s)
- Benson S Chen
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge CB2 0QQ, United Kingdom
| | - Patrick Yu-Wai-Man
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge CB2 0QQ, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, United Kingdom
- Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
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Zhang J, Wang L, Ding H, Fan K, Tian Q, Liang M, Sun Z, Shi D, Qin W. Abnormal large-scale structural rich club organization in Leber's hereditary optic neuropathy. NEUROIMAGE-CLINICAL 2021; 30:102619. [PMID: 33752075 PMCID: PMC8010853 DOI: 10.1016/j.nicl.2021.102619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 02/23/2021] [Accepted: 03/02/2021] [Indexed: 12/24/2022]
Abstract
LHON patients suffered large-scale structural network disruption. Non-rich club connections may be more vulnerable in the LHON. Both primary and secondary connectivity damage may coexist in the LHON.
Objective The purpose of this study was to investigate whether the large-scale structural rich club organization was abnormal in patients with Leber's hereditary optic neuropathy (LHON) using diffusion tensor imaging (DTI), and the associations among disrupted brain structural connectivity, disease duration, and neuro-ophthalmological impairment. Methods Nineteen acute, 34 chronic LHON patients, and 36 healthy controls (HC) underwent DTI and neuro-ophthalmological measurements. The brain structural network and rich club organization were constructed based on deterministic fiber tracking at the individual level. Then intergroup differences among the acute, chronic LHON patients and healthy controls (HC) in three types of structural connections, including rich club, feeder, and local ones, were compared. Network-based Statistics (NBS) was also used to test the intergroup connectivity differences for each fiber. Several linear and nonlinear curve fit models were applied to explore the associations among large-scale brain structural connectivity, disease duration, and neuro-ophthalmological metrics. Results Compared to the HC, both the acute and chronic LHON patients had consistently significantly lower fractional anisotropy (FA) and higher radial diffusion (RD) for feeder connections (p < 0.05, FDR correction). Acute LHON patients had significantly lower FA and higher RD for local connections (p < 0.05, FDR correction). There was no significant difference in large-scale brain structural connectivity between acute and chronic LHON (p > 0.05, FDR correction). NBS also identified reduced FA of three feeder connections and five local ones linking visual, auditory, and basal ganglia areas in LHON patients (p < 0.05, FDR correction). No structural connections showed linear or nonlinear association with either disease duration or neuro-ophthalmological indicators (p > 0.05, FDR correction). A significant negative correlation was shown between the retinal nerve fiber layer (RNFL) thickness and disease duration (p < 0.05, FDR correction). Conclusions Abnormal rich club organization of the structural network was identified in both the acute and chronic LHON. Furthermore, our findings suggest the coexistence of both primary and secondary connectivity damage in the LHON.
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Affiliation(s)
- Jiahui Zhang
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Ling Wang
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Hao Ding
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China; School of Medical Imaging, Tianjin Medical University, Tianjin 300070, China
| | - Ke Fan
- Henan Eye Institute, Henan Eye Hospital, Zhengzhou University People's Hospital, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Qin Tian
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Meng Liang
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China; School of Medical Imaging, Tianjin Medical University, Tianjin 300070, China
| | - Zhihua Sun
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Dapeng Shi
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou 450003, China.
| | - Wen Qin
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China.
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Montano V, Gruosso F, Simoncini C, Siciliano G, Mancuso M. Clinical features of mtDNA-related syndromes in adulthood. Arch Biochem Biophys 2020; 697:108689. [PMID: 33227288 DOI: 10.1016/j.abb.2020.108689] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/06/2020] [Accepted: 11/15/2020] [Indexed: 01/26/2023]
Abstract
Mitochondrial diseases are the most common inheritable metabolic diseases, due to defects in oxidative phosphorylation. They are caused by mutations of nuclear or mitochondrial DNA in genes involved in mitochondrial function. The peculiarity of "mitochondrial DNA genetics rules" in part explains the marked phenotypic variability, the complexity of genotype-phenotype correlations and the challenge of genetic counseling. The new massive genetic sequencing technologies have changed the diagnostic approach, enhancing mitochondrial DNA-related syndromes diagnosis and often avoiding the need of a tissue biopsy. Here we present the most common phenotypes associated with a mitochondrial DNA mutation with the recent advances in diagnosis and in therapeutic perspectives.
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Affiliation(s)
- V Montano
- Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa, Italy
| | - F Gruosso
- Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa, Italy
| | - C Simoncini
- Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa, Italy
| | - G Siciliano
- Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa, Italy
| | - M Mancuso
- Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa, Italy.
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Rovcanin B, Jancic J, Samardzic J, Rovcanin M, Nikolic B, Ivancevic N, Novakovic I, Kostic V. In silico model of mtDNA mutations effect on secondary and 3D structure of mitochondrial rRNA and tRNA in Leber's hereditary optic neuropathy. Exp Eye Res 2020; 201:108277. [PMID: 32991883 DOI: 10.1016/j.exer.2020.108277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 09/05/2020] [Accepted: 09/25/2020] [Indexed: 02/03/2023]
Abstract
The Leber's hereditary optic neuropathy (LHON) is a rare disease caused by mitochondrial DNA (mtDNA) mutations. Beside primary mutations, the effect of secondary mtDNA mutations in still unclear. We examined the effect of secondary mtDNA mutations on secondary structure of different mitochondrial RNAs. Whole mitochondrial genome sequence of LHON patients has been obtained from in six non related pedigrees by Sanger sequencing method. The effect of mutations located in mitochondrial RNA genes was examined by creating in silico models of RNA secondary and regional 3D structure, accompanied by sequence conservation analysis. All three primary LHON mutations (m.3460G>A, m.11778G>A and m.14484 T>C) were revealed in study families. Four mutations in MT-RNR1 gene (m.750A>G, m.956delC, m.1438A>G and m.1555A>G) were identified and only an m.1555A>G causes significant changes of secondary structure of mitochondrial 12S ribosomal RNA (rRNA), while it is the only mutation which does not alter its 3D structure. Five mutations (m.1811A>G, m.2706A>G, m.2831G>A, m.3010G>A and m.3197T>C) were discovered in MT-RNR2 gene and all of them induced substantial alterations of mitochondrial 16S rRNA secondary structure. Significant changes of mitochondrial 16S rRNA 3D structure are caused by m.1811A>G, m.2706A>G, m.3010G>A and m.3197T>C. A single insertion variant (m.15986insG) has been found in the MT-TP gene which encodes mitochondrial transfer RNA for Proline (tRNA Pro). This mutation does not cause substantial changes of tRNA for Proline secondary structure, while the 3D geometry remains without major changes. Most of the mutation loci exhibited high level of sequence conservation. Presence of multiple mutations in a single family appears to cause more extensive changes in mitochondrial 12S and 16S rRNA, then their individual influence. The effect of discovered mutations on in silico modelled RNA structure is in a significant correlation with the present knowledge about the potential of these mutation to participate in the pathophysiology of LHON and other human diseases. The presence of certain multiple mitochondrial RNA mutations could be a possible explanation of LHON clinical presentation in some families. All revealed mutations have been evaluated for the first time in terms of in silico structural modelling. The application of bioinformatics tools such as secondary and 3D RNA structure prediction can have a great advantage in better understanding of the molecular standpoint of the LHON pathophysiology and clinical phenotype.
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Affiliation(s)
- Branislav Rovcanin
- Center for Endocrine Surgery, Clinical Center of Serbia, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
| | - Jasna Jancic
- Clinic of Neurology and Psychiatry for Children and Youth, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Janko Samardzic
- Clinic of Neurology and Psychiatry for Children and Youth, Faculty of Medicine, University of Belgrade, Belgrade, Serbia; Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Marija Rovcanin
- The Obstetrics and Gynecology Clinic Narodni Front, Belgrade, Serbia
| | - Blazo Nikolic
- Clinic of Neurology and Psychiatry for Children and Youth, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Nikola Ivancevic
- Clinic of Neurology and Psychiatry for Children and Youth, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ivana Novakovic
- Institute for Human Genetics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Vladimir Kostic
- Clinic of Neurology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
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