1
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Veeraragavan S, Johansen M, Johnston IG. Evolution and maintenance of mtDNA gene content across eukaryotes. Biochem J 2024; 481:1015-1042. [PMID: 39101615 PMCID: PMC11346449 DOI: 10.1042/bcj20230415] [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: 04/08/2024] [Revised: 06/26/2024] [Accepted: 07/18/2024] [Indexed: 08/06/2024]
Abstract
Across eukaryotes, most genes required for mitochondrial function have been transferred to, or otherwise acquired by, the nucleus. Encoding genes in the nucleus has many advantages. So why do mitochondria retain any genes at all? Why does the set of mtDNA genes vary so much across different species? And how do species maintain functionality in the mtDNA genes they do retain? In this review, we will discuss some possible answers to these questions, attempting a broad perspective across eukaryotes. We hope to cover some interesting features which may be less familiar from the perspective of particular species, including the ubiquity of recombination outside bilaterian animals, encrypted chainmail-like mtDNA, single genes split over multiple mtDNA chromosomes, triparental inheritance, gene transfer by grafting, gain of mtDNA recombination factors, social networks of mitochondria, and the role of mtDNA dysfunction in feeding the world. We will discuss a unifying picture where organismal ecology and gene-specific features together influence whether organism X retains mtDNA gene Y, and where ecology and development together determine which strategies, importantly including recombination, are used to maintain the mtDNA genes that are retained.
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Affiliation(s)
| | - Maria Johansen
- Department of Mathematics, University of Bergen, Bergen, Norway
| | - Iain G. Johnston
- Department of Mathematics, University of Bergen, Bergen, Norway
- Computational Biology Unit, University of Bergen, Bergen, Norway
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2
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Bury A, Pyle A, Vincent AE, Actis P, Hudson G. Nanobiopsy investigation of the subcellular mtDNA heteroplasmy in human tissues. Sci Rep 2024; 14:13789. [PMID: 38877095 PMCID: PMC11178779 DOI: 10.1038/s41598-024-64455-0] [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] [Received: 06/22/2023] [Accepted: 06/10/2024] [Indexed: 06/16/2024] Open
Abstract
Mitochondrial function is critical to continued cellular vitality and is an important contributor to a growing number of human diseases. Mitochondrial dysfunction is typically heterogeneous, mediated through the clonal expansion of mitochondrial DNA (mtDNA) variants in a subset of cells in a given tissue. To date, our understanding of the dynamics of clonal expansion of mtDNA variants has been technically limited to the single cell-level. Here, we report the use of nanobiopsy for subcellular sampling from human tissues, combined with next-generation sequencing to assess subcellular mtDNA mutation load in human tissue from mitochondrial disease patients. The ability to map mitochondrial mutation loads within individual cells of diseased tissue samples will further our understanding of mitochondrial genetic diseases.
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Affiliation(s)
- Alexander Bury
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
- NIHR Biomedical Research Centre, Faculty of Medical Science, Newcastle University, Newcastle, UK
- School of Electronic and Electrical Engineering and Pollard Institute, University of Leeds, Leeds, UK
- Bragg Centre for Materials Research, Leeds, UK
| | - Angela Pyle
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | - Amy E Vincent
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle, UK.
- NIHR Biomedical Research Centre, Faculty of Medical Science, Newcastle University, Newcastle, UK.
| | - Paolo Actis
- School of Electronic and Electrical Engineering and Pollard Institute, University of Leeds, Leeds, UK.
- Bragg Centre for Materials Research, Leeds, UK.
| | - Gavin Hudson
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle, UK.
- NIHR Biomedical Research Centre, Faculty of Medical Science, Newcastle University, Newcastle, UK.
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3
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Phua QH, Ng SY, Soh BS. Mitochondria: A Potential Rejuvenation Tool against Aging. Aging Dis 2024; 15:503-516. [PMID: 37815912 PMCID: PMC10917551 DOI: 10.14336/ad.2023.0712] [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: 05/26/2023] [Accepted: 07/12/2023] [Indexed: 10/12/2023] Open
Abstract
Aging is a complex physiological process encompassing both physical and cognitive decline over time. This intricate process is governed by a multitude of hallmarks and pathways, which collectively contribute to the emergence of numerous age-related diseases. In response to the remarkable increase in human life expectancy, there has been a substantial rise in research focusing on the development of anti-aging therapies and pharmacological interventions. Mitochondrial dysfunction, a critical factor in the aging process, significantly impacts overall cellular health. In this extensive review, we will explore the contemporary landscape of anti-aging strategies, placing particular emphasis on the promising potential of mitotherapy as a ground-breaking approach to counteract the aging process. Moreover, we will investigate the successful application of mitochondrial transplantation in both animal models and clinical trials, emphasizing its translational potential. Finally, we will discuss the inherent challenges and future possibilities of mitotherapy within the realm of aging research and intervention.
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Affiliation(s)
- Qian Hua Phua
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Proteos, Singapore.
- Department of Biological Sciences, National University of Singapore, Singapore.
| | - Shi Yan Ng
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Proteos, Singapore.
- National University of Singapore, Yong Loo Lin School of Medicine (Department of Physiology), Singapore.
- National Neuroscience Institute, Singapore.
| | - Boon-Seng Soh
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Proteos, Singapore.
- Department of Biological Sciences, National University of Singapore, Singapore.
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4
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Takeda Y, Hyslop L, Choudhary M, Robertson F, Pyle A, Wilson I, Santibanez‐Koref M, Turnbull D, Herbert M, Hudson G. Feasibility and impact of haplogroup matching for mitochondrial replacement treatment. EMBO Rep 2023; 24:e54540. [PMID: 37589175 PMCID: PMC10561356 DOI: 10.15252/embr.202154540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 07/03/2023] [Accepted: 07/26/2023] [Indexed: 08/18/2023] Open
Abstract
Mitochondrial replacement technology (MRT) aims to reduce the risk of serious disease in children born to women who carry pathogenic mitochondrial DNA (mtDNA) variants. By transplanting nuclear genomes from eggs of an affected woman to enucleated eggs from an unaffected donor, MRT creates new combinations of nuclear and mtDNA. Based on sets of shared sequence variants, mtDNA is classified into ~30 haplogroups. Haplogroup matching between egg donors and women undergoing MRT has been proposed as a means of reducing mtDNA sequence divergence between them. Here we investigate the potential effect of mtDNA haplogroup matching on clinical delivery of MRT and on mtDNA sequence divergence between donor/recipient pairs. Our findings indicate that haplogroup matching would limit the availability of egg donors such that women belonging to rare haplogroups may have to wait > 4 years for treatment. Moreover, we find that intra-haplogroup sequence variation is frequently within the range observed between randomly matched mtDNA pairs. We conclude that haplogroup matching would restrict the availability of MRT, without necessarily reducing mtDNA sequence divergence between donor/recipient pairs.
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Affiliation(s)
- Yuko Takeda
- Wellcome Centre for Mitochondrial Research, Biosciences InstituteNewcastle UniversityNewcastle upon TyneUK
| | - Louise Hyslop
- Newcastle Fertility Centre, Biomedicine West WingCentre for LifeNewcastle upon TyneUK
| | - Meenakshi Choudhary
- Newcastle Fertility Centre, Biomedicine West WingCentre for LifeNewcastle upon TyneUK
| | - Fiona Robertson
- Wellcome Centre for Mitochondrial ResearchInstitute of Clinical Translational Research, Newcastle UniversityNewcastle upon TyneUK
| | - Angela Pyle
- Wellcome Centre for Mitochondrial ResearchInstitute of Clinical Translational Research, Newcastle UniversityNewcastle upon TyneUK
| | - Ian Wilson
- Biosciences Institute, Centre for LifeNewcastle upon TyneUK
| | | | - Douglass Turnbull
- Wellcome Centre for Mitochondrial ResearchInstitute of Clinical Translational Research, Newcastle UniversityNewcastle upon TyneUK
| | - Mary Herbert
- Wellcome Centre for Mitochondrial Research, Biosciences InstituteNewcastle UniversityNewcastle upon TyneUK
- Newcastle Fertility Centre, Biomedicine West WingCentre for LifeNewcastle upon TyneUK
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery InstituteMonash UniversityMelbourneVICAustralia
| | - Gavin Hudson
- Wellcome Centre for Mitochondrial Research, Biosciences InstituteNewcastle UniversityNewcastle upon TyneUK
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5
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D'Amato M, Morra F, Di Meo I, Tiranti V. Mitochondrial Transplantation in Mitochondrial Medicine: Current Challenges and Future Perspectives. Int J Mol Sci 2023; 24:1969. [PMID: 36768312 PMCID: PMC9916997 DOI: 10.3390/ijms24031969] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
Mitochondrial diseases (MDs) are inherited genetic conditions characterized by pathogenic mutations in nuclear DNA (nDNA) or mitochondrial DNA (mtDNA). Current therapies are still far from being fully effective and from covering the broad spectrum of mutations in mtDNA. For example, unlike heteroplasmic conditions, MDs caused by homoplasmic mtDNA mutations do not yet benefit from advances in molecular approaches. An attractive method of providing dysfunctional cells and/or tissues with healthy mitochondria is mitochondrial transplantation. In this review, we discuss what is known about intercellular transfer of mitochondria and the methods used to transfer mitochondria both in vitro and in vivo, and we provide an outlook on future therapeutic applications. Overall, the transfer of healthy mitochondria containing wild-type mtDNA copies could induce a heteroplasmic shift even when homoplasmic mtDNA variants are present, with the aim of attenuating or preventing the progression of pathological clinical phenotypes. In summary, mitochondrial transplantation is a challenging but potentially ground-breaking option for the treatment of various mitochondrial pathologies, although several questions remain to be addressed before its application in mitochondrial medicine.
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Affiliation(s)
- Marco D'Amato
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Francesca Morra
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Ivano Di Meo
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Valeria Tiranti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
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6
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Burgstaller JP, Chiaratti MR. Mitochondrial Inheritance Following Nuclear Transfer: From Cloned Animals to Patients with Mitochondrial Disease. Methods Mol Biol 2023; 2647:83-104. [PMID: 37041330 DOI: 10.1007/978-1-0716-3064-8_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Mitochondria are indispensable power plants of eukaryotic cells that also act as a major biochemical hub. As such, mitochondrial dysfunction, which can originate from mutations in the mitochondrial genome (mtDNA), may impair organism fitness and lead to severe diseases in humans. MtDNA is a multi-copy, highly polymorphic genome that is uniparentally transmitted through the maternal line. Several mechanisms act in the germline to counteract heteroplasmy (i.e., coexistence of two or more mtDNA variants) and prevent expansion of mtDNA mutations. However, reproductive biotechnologies such as cloning by nuclear transfer can disrupt mtDNA inheritance, resulting in new genetic combinations that may be unstable and have physiological consequences. Here, we review the current understanding of mitochondrial inheritance, with emphasis on its pattern in animals and human embryos generated by nuclear transfer.
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Affiliation(s)
- Jörg P Burgstaller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine, Vienna, Austria
| | - Marcos R Chiaratti
- Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, Brazil.
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7
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Chen Y, Yang F, Chu Y, Yun Z, Yan Y, Jin J. Mitochondrial transplantation: opportunities and challenges in the treatment of obesity, diabetes, and nonalcoholic fatty liver disease. Lab Invest 2022; 20:483. [PMID: 36273156 PMCID: PMC9588235 DOI: 10.1186/s12967-022-03693-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 10/06/2022] [Indexed: 11/23/2022]
Abstract
Metabolic diseases, including obesity, diabetes, and nonalcoholic fatty liver disease (NAFLD), are rising in both incidence and prevalence and remain a major global health and socioeconomic burden in the twenty-first century. Despite an increasing understanding of these diseases, the lack of effective treatments remains an ongoing challenge. Mitochondria are key players in intracellular energy production, calcium homeostasis, signaling, and apoptosis. Emerging evidence shows that mitochondrial dysfunction participates in the pathogeneses of metabolic diseases. Exogenous supplementation with healthy mitochondria is emerging as a promising therapeutic approach to treating these diseases. This article reviews recent advances in the use of mitochondrial transplantation therapy (MRT) in such treatment.
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Affiliation(s)
- Yifei Chen
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.,School of Medicine, Jiangsu University, ZhenjiangJiangsu Province, 212013, China
| | - Fuji Yang
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.,School of Medicine, Jiangsu University, ZhenjiangJiangsu Province, 212013, China
| | - Ying Chu
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.,Central Laboratory, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China
| | - Zhihua Yun
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China
| | - Yongmin Yan
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China. .,Central Laboratory, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.
| | - Jianhua Jin
- Department of Oncology, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.
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8
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Zhang TG, Miao CY. Mitochondrial transplantation as a promising therapy for mitochondrial diseases. Acta Pharm Sin B 2022; 13:1028-1035. [PMID: 36970208 PMCID: PMC10031255 DOI: 10.1016/j.apsb.2022.10.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/25/2022] [Accepted: 08/18/2022] [Indexed: 11/28/2022] Open
Abstract
Mitochondrial diseases are a group of inherited or acquired metabolic disorders caused by mitochondrial dysfunction which may affect almost all the organs in the body and present at any age. However, no satisfactory therapeutic strategies have been available for mitochondrial diseases so far. Mitochondrial transplantation is a burgeoning approach for treatment of mitochondrial diseases by recovery of dysfunctional mitochondria in defective cells using isolated functional mitochondria. Many models of mitochondrial transplantation in cells, animals, and patients have proved effective via various routes of mitochondrial delivery. This review presents different techniques used in mitochondrial isolation and delivery, mechanisms of mitochondrial internalization and consequences of mitochondrial transplantation, along with challenges for clinical application. Despite some unknowns and challenges, mitochondrial transplantation would provide an innovative approach for mitochondrial medicine.
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Affiliation(s)
| | - Chao-yu Miao
- Corresponding author. Tel: +86 21 81871271; fax: +86 21 65493951.
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9
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Lima A, Lubatti G, Burgstaller J, Hu D, Green AP, Di Gregorio A, Zawadzki T, Pernaute B, Mahammadov E, Perez-Montero S, Dore M, Sanchez JM, Bowling S, Sancho M, Kolbe T, Karimi MM, Carling D, Jones N, Srinivas S, Scialdone A, Rodriguez TA. Cell competition acts as a purifying selection to eliminate cells with mitochondrial defects during early mouse development. Nat Metab 2021; 3:1091-1108. [PMID: 34253906 PMCID: PMC7611553 DOI: 10.1038/s42255-021-00422-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 06/02/2021] [Indexed: 12/13/2022]
Abstract
Cell competition is emerging as a quality-control mechanism that eliminates unfit cells in a wide range of settings from development to the adult. However, the nature of the cells normally eliminated by cell competition and what triggers their elimination remains poorly understood. In mice, 35% of epiblast cells are eliminated before gastrulation. Here we show that cells with mitochondrial defects are eliminated by cell competition during early mouse development. Using single-cell transcriptional profiling of eliminated mouse epiblast cells, we identify hallmarks of cell competition and mitochondrial defects. We demonstrate that mitochondrial defects are common to a range of different loser cell types and that manipulating mitochondrial function triggers cell competition. Moreover, we show that in the mouse embryo, cell competition eliminates cells with sequence changes in mt-Rnr1 and mt-Rnr2, and that even non-pathological changes in mitochondrial DNA sequences can induce cell competition. Our results suggest that cell competition is a purifying selection that optimizes mitochondrial performance before gastrulation.
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Affiliation(s)
- Ana Lima
- National Heart and Lung Institute, Imperial College London, London, UK
- MRC London Institute of Medical Sciences (LMS), Institute of Clinical Sciences, Imperial College London, London, UK
| | - Gabriele Lubatti
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Munich, Germany
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Jörg Burgstaller
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine, Vienna, Austria
| | - Di Hu
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Alistair P Green
- EPSRC Centre for the Mathematics of Precision Healthcare, Department of Mathematics, Imperial College London, London, UK
| | - Aida Di Gregorio
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Tamzin Zawadzki
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Barbara Pernaute
- National Heart and Lung Institute, Imperial College London, London, UK
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Elmir Mahammadov
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Munich, Germany
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | | | - Marian Dore
- MRC London Institute of Medical Sciences (LMS), Institute of Clinical Sciences, Imperial College London, London, UK
| | - Juan Miguel Sanchez
- National Heart and Lung Institute, Imperial College London, London, UK
- Orchard Therapeutics, London, UK
| | - Sarah Bowling
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Margarida Sancho
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Thomas Kolbe
- Biomodels Austria (Biat), University of Veterinary Medicine Vienna, Vienna, Austria
- Department IFA-Tulln, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Mohammad M Karimi
- MRC London Institute of Medical Sciences (LMS), Institute of Clinical Sciences, Imperial College London, London, UK
- Comprehensive Cancer Centre, School of Cancer & Pharmaceutical Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - David Carling
- MRC London Institute of Medical Sciences (LMS), Institute of Clinical Sciences, Imperial College London, London, UK
| | - Nick Jones
- EPSRC Centre for the Mathematics of Precision Healthcare, Department of Mathematics, Imperial College London, London, UK
| | - Shankar Srinivas
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Antonio Scialdone
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, Munich, Germany.
- Institute of Functional Epigenetics, Helmholtz Zentrum München, Neuherberg, Germany.
- Institute of Computational Biology, Helmholtz Zentrum München, Neuherberg, Germany.
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10
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Cytoplasmic Transfer Improves Human Egg Fertilization and Embryo Quality: an Evaluation of Sibling Oocytes in Women with Low Oocyte Quality. Reprod Sci 2020; 28:1362-1369. [PMID: 33155170 PMCID: PMC8076124 DOI: 10.1007/s43032-020-00371-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 10/21/2020] [Indexed: 11/29/2022]
Abstract
The aim of this study was to evaluate if cytoplasmic transfer can improve fertilization and embryo quality of women with oocytes of low quality. During ICSI, 10–15% of the cytoplasm from a fresh or frozen young donor oocyte was added to the recipient oocyte. According to the embryo quality, we defined group A as patients in which the best embryo was evident after cytoplasmic transfer and group B as patients in which the best embryo was evident after a simple ICSI. We investigated in the period of 2002–2018, 125 in vitro fertilization cycles involving 1011 fertilized oocytes. Five hundred fifty-seven sibling oocytes were fertilized using ICSI only and 454 oocytes with cytoplasmic transfer. Fertilization rates of oocytes were 67.2% in the cytoplasmic transfer and 53.5% in the ICSI groups (P < 0.001). A reduction in fertilization rate was observed with increased women age in the ICSI but not in the cytoplasmic transfer groups. The best embryo quality was found after cytoplasmic transfer in 78 cycles (62.4%) and without cytoplasmic transfer in 40 cycles (32%, P < 0.001). No significant differences were detected between the age, hormonal levels, dose of stimulation drugs, number of transferred embryos, pregnancy rate and abortion rate between A and B groups. Cytoplasmic transfer improves fertilization rates and early embryo development in humans with low oocyte quality. All 28 children resulting from cytoplasmic transfer are healthy.
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11
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Ogawa T, Fukasawa H, Hirata S. Improvement of early developmental competence of postovulatory-aged oocytes using metaphase II spindle injection in mice. Reprod Med Biol 2020; 19:357-364. [PMID: 33071637 PMCID: PMC7542019 DOI: 10.1002/rmb2.12335] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/03/2020] [Accepted: 06/08/2020] [Indexed: 11/25/2022] Open
Abstract
Purpose Assisted reproductive technology (ART) is a widely applied fertility treatment. However, the developmental competence of aged oocytes from women of a late reproductive age is seriously reduced and the aged oocytes often fail in fertilization even when ART is used. To resolve this problem, we examined usefulness of a new method “the metaphase II spindle transfer (MESI)” as ART using mouse oocytes. Methods This work was composed of two experiments. First, 24 hours after collection, embryos from oocytes (1‐day‐old oocytes, called postovulatory‐aged oocytes), were observed, after intracytoplasmic sperm injection (ICSI), and it was found that they were not able to reach the blastocyst stage. Next, the metaphase II chromosome‐spindle complexes from 1‐day‐old oocytes were injected into cytoplasts from oocytes just collected, using piezo pulses to generate reconstructed oocytes. This procedure was named metaphase II spindle injection (MESI). Results After ICSI, embryos from the reconstructed oocytes (32/105), which contained the genes of 1‐day‐old oocytes, were able to develop into the blastocyst stage. The fragmentation rate after ICSI was 28.6%. Thus, the developmental competence of 1‐day‐old oocytes was improved by MESI. Conclusions The MESI method has the potential to improve the success rate of infertility treatments for women of a late reproductive age.
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Affiliation(s)
- Tatsuyuki Ogawa
- Department of Obstetrics and Gynecology Faculty of Medicine University of Yamanashi Chuo Japan
| | - Hiroko Fukasawa
- Department of Obstetrics and Gynecology Faculty of Medicine University of Yamanashi Chuo Japan
| | - Shuji Hirata
- Department of Obstetrics and Gynecology Faculty of Medicine University of Yamanashi Chuo Japan
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12
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Wang X, Jia L, Wang M, Yang H, Chen M, Li X, Liu H, Li Q, Liu N. The complete mitochondrial genome of medicinal fungus Taiwanofungus camphoratus reveals gene rearrangements and intron dynamics of Polyporales. Sci Rep 2020; 10:16500. [PMID: 33020532 PMCID: PMC7536210 DOI: 10.1038/s41598-020-73461-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 09/08/2020] [Indexed: 12/31/2022] Open
Abstract
Taiwanofungus camphoratus is a highly valued medicinal mushroom that is endemic to Taiwan, China. In the present study, the mitogenome of T. camphoratus was assembled and compared with other published Polyporales mitogenomes. The T. camphoratus mitogenome was composed of circular DNA molecules, with a total size of 114,922 bp. Genome collinearity analysis revealed large-scale gene rearrangements between the mitogenomes of Polyporales, and T. camphoratus contained a unique gene order. The number and classes of introns were highly variable in 12 Polyporales species we examined, which proved that numerous intron loss or gain events occurred in the evolution of Polyporales. The Ka/Ks values for most core protein coding genes in Polyporales species were less than 1, indicating that these genes were subject to purifying selection. However, the rps3 gene was found under positive or relaxed selection between some Polyporales species. Phylogenetic analysis based on the combined mitochondrial gene set obtained a well-supported topology, and T. camphoratus was identified as a sister species to Laetiporus sulphureus. This study served as the first report on the mitogenome in the Taiwanofungus genus, which will provide a basis for understanding the phylogeny and evolution of this important fungus.
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Affiliation(s)
- Xu Wang
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Lihua Jia
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Mingdao Wang
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Hao Yang
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Mingyue Chen
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Xiao Li
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Hanyu Liu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China
| | - Qiang Li
- School of Food and Biological Engineering, Chengdu University, Chengdu, 610106, Sichuan, China.
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China.
| | - Na Liu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China.
- College of Life Sciences, Henan Agricultural University, Zhengzhou, 450002, Henan, China.
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13
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Røyrvik EC, Johnston IG. MtDNA sequence features associated with 'selfish genomes' predict tissue-specific segregation and reversion. Nucleic Acids Res 2020; 48:8290-8301. [PMID: 32716035 PMCID: PMC7470939 DOI: 10.1093/nar/gkaa622] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/25/2020] [Accepted: 07/15/2020] [Indexed: 12/31/2022] Open
Abstract
Mitochondrial DNA (mtDNA) encodes cellular machinery vital for cell and organism survival. Mutations, genetic manipulation, and gene therapies may produce cells where different types of mtDNA coexist in admixed populations. In these admixtures, one mtDNA type is often observed to proliferate over another, with different types dominating in different tissues. This ‘segregation bias’ is a long-standing biological mystery that may pose challenges to modern mtDNA disease therapies, leading to substantial recent attention in biological and medical circles. Here, we show how an mtDNA sequence’s balance between replication and transcription, corresponding to molecular ‘selfishness’, in conjunction with cellular selection, can potentially modulate segregation bias. We combine a new replication-transcription-selection (RTS) model with a meta-analysis of existing data to show that this simple theory predicts complex tissue-specific patterns of segregation in mouse experiments, and reversion in human stem cells. We propose the stability of G-quadruplexes in the mtDNA control region, influencing the balance between transcription and replication primer formation, as a potential molecular mechanism governing this balance. Linking mtDNA sequence features, through this molecular mechanism, to cellular population dynamics, we use sequence data to obtain and verify the sequence-specific predictions from this hypothesis on segregation behaviour in mouse and human mtDNA.
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Affiliation(s)
- Ellen C Røyrvik
- Department of Clinical Science, University of Bergen, Norway.,K.G. Jebsen Center for Autoimmune Diseases, University of Bergen, Norway
| | - Iain G Johnston
- Department of Mathematics, University of Bergen, Norway.,Alan Turing Institute, London, UK
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14
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Recurrent horizontal transfer identifies mitochondrial positive selection in a transmissible cancer. Nat Commun 2020; 11:3059. [PMID: 32546718 PMCID: PMC7297733 DOI: 10.1038/s41467-020-16765-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 05/26/2020] [Indexed: 01/27/2023] Open
Abstract
Autonomous replication and segregation of mitochondrial DNA (mtDNA) creates the potential for evolutionary conflict driven by emergence of haplotypes under positive selection for 'selfish' traits, such as replicative advantage. However, few cases of this phenomenon arising within natural populations have been described. Here, we survey the frequency of mtDNA horizontal transfer within the canine transmissible venereal tumour (CTVT), a contagious cancer clone that occasionally acquires mtDNA from its hosts. Remarkably, one canine mtDNA haplotype, A1d1a, has repeatedly and recently colonised CTVT cells, recurrently replacing incumbent CTVT haplotypes. An A1d1a control region polymorphism predicted to influence transcription is fixed in the products of an A1d1a recombination event and occurs somatically on other CTVT mtDNA backgrounds. We present a model whereby 'selfish' positive selection acting on a regulatory variant drives repeated fixation of A1d1a within CTVT cells.
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15
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Evolving mtDNA populations within cells. Biochem Soc Trans 2020; 47:1367-1382. [PMID: 31484687 PMCID: PMC6824680 DOI: 10.1042/bst20190238] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/06/2019] [Accepted: 08/08/2019] [Indexed: 12/14/2022]
Abstract
Mitochondrial DNA (mtDNA) encodes vital respiratory machinery. Populations of mtDNA molecules exist in most eukaryotic cells, subject to replication, degradation, mutation, and other population processes. These processes affect the genetic makeup of cellular mtDNA populations, changing cell-to-cell distributions, means, and variances of mutant mtDNA load over time. As mtDNA mutant load has nonlinear effects on cell functionality, and cell functionality has nonlinear effects on tissue performance, these statistics of cellular mtDNA populations play vital roles in health, disease, and inheritance. This mini review will describe some of the better-known ways in which these populations change over time in different organisms, highlighting the importance of quantitatively understanding both mutant load mean and variance. Due to length constraints, we cannot attempt to be comprehensive but hope to provide useful links to some of the many excellent studies on these topics.
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16
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Barrett A, Arbeithuber B, Zaidi A, Wilton P, Paul IM, Nielsen R, Makova KD. Pronounced somatic bottleneck in mitochondrial DNA of human hair. Philos Trans R Soc Lond B Biol Sci 2019; 375:20190175. [PMID: 31787049 PMCID: PMC6939377 DOI: 10.1098/rstb.2019.0175] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Heteroplasmy is the presence of variable mitochondrial DNA (mtDNA) within the same individual. The dynamics of heteroplasmy allele frequency among tissues of the human body is not well understood. Here, we measured allele frequency at heteroplasmic sites in two to eight hairs from each of 11 humans using next-generation sequencing. We observed a high variance in heteroplasmic allele frequency among separate hairs from the same individual—much higher than that for blood and cheek tissues. Our population genetic modelling estimated the somatic bottleneck during embryonic follicle development of separate hairs to be only 11.06 (95% confidence interval 0.6–34.0) mtDNA segregating units. This bottleneck is much more drastic than somatic bottlenecks for blood and cheek tissues (136 and 458 units, respectively), as well as more drastic than, or comparable to, the germline bottleneck (equal to 25–32 or 7–10 units, depending on the study). We demonstrated that hair undergoes additional genetic drift before and after the divergence of mtDNA lineages of individual hair follicles. Additionally, we showed a positive correlation between donor's age and variance in heteroplasmy allele frequency in hair. These findings have important implications for forensics and for our understanding of mtDNA dynamics in the human body. This article is part of the theme issue ‘Linking the mitochondrial genotype to phenotype: a complex endeavour’.
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Affiliation(s)
- Alison Barrett
- Department of Biology, Penn State University, University Park, PA, USA
| | | | - Arslan Zaidi
- Department of Biology, Penn State University, University Park, PA, USA
| | - Peter Wilton
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA, USA
| | - Ian M Paul
- Department of Pediatrics, Penn State College of Medicine, Hershey, PA, USA
| | - Rasmus Nielsen
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA, USA
| | - Kateryna D Makova
- Department of Biology, Penn State University, University Park, PA, USA
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17
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Johnston IG. Varied Mechanisms and Models for the Varying Mitochondrial Bottleneck. Front Cell Dev Biol 2019; 7:294. [PMID: 31824946 PMCID: PMC6879659 DOI: 10.3389/fcell.2019.00294] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 11/06/2019] [Indexed: 12/22/2022] Open
Abstract
Mitochondrial DNA (mtDNA) molecules exist in populations within cells, and may carry mutations. Different cells within an organism, and organisms within a family, may have different proportions of mutant mtDNA in these cellular populations. This diversity is often thought of as arising from a “genetic bottleneck.” This article surveys approaches to characterize and model the generation of this genetic diversity, aiming to provide an introduction to the range of concepts involved, and to highlight some recent advances in understanding. In particular, differences between the statistical “genetic bottleneck” (mutant proportion spread) and the physical mtDNA bottleneck and other cellular processes are highlighted. Particular attention is paid to the quantitative analysis of the “genetic bottleneck,” estimation of its magnitude from observed data, and inference of its underlying mechanisms. Evidence that the “genetic bottleneck” (mutant proportion spread) varies with age, between individuals and species, and across mtDNA sequences, is described. The interpretation issues that arise from sampling errors, selection, and different quantitative definitions are also discussed.
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Affiliation(s)
- Iain G Johnston
- Department of Mathematics, Faculty of Mathematics and Natural Sciences, University of Bergen, Bergen, Norway
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18
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Al Khatib I, Shutt TE. Advances Towards Therapeutic Approaches for mtDNA Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1158:217-246. [PMID: 31452143 DOI: 10.1007/978-981-13-8367-0_12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mitochondria maintain and express their own genome, referred to as mtDNA, which is required for proper mitochondrial function. While mutations in mtDNA can cause a heterogeneous array of disease phenotypes, there is currently no cure for this collection of diseases. Here, we will cover characteristics of the mitochondrial genome important for understanding the pathology associated with mtDNA mutations, and review recent approaches that are being developed to treat and prevent mtDNA disease. First, we will discuss mitochondrial replacement therapy (MRT), where mitochondria from a healthy donor replace maternal mitochondria harbouring mutant mtDNA. In addition to ethical concerns surrounding this procedure, MRT is only applicable in cases where the mother is known or suspected to carry mtDNA mutations. Thus, there remains a need for other strategies to treat patients with mtDNA disease. To this end, we will also discuss several alternative means to reduce the amount of mutant mtDNA present in cells. Such methods, referred to as heteroplasmy shifting, have proven successful in animal models. In particular, we will focus on the approach of targeting engineered endonucleases to specifically cleave mutant mtDNA. Together, these approaches offer hope to prevent the transmission of mtDNA disease and potentially reduce the impact of mtDNA mutations.
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Affiliation(s)
- Iman Al Khatib
- Deparments of Medical Genetics and Biochemistry & Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Timothy E Shutt
- Deparments of Medical Genetics and Biochemistry & Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
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Poulton J, Steffann J, Burgstaller J, McFarland R. 243rd ENMC international workshop: Developing guidelines for management of reproductive options for families with maternally inherited mtDNA disease, Amsterdam, the Netherlands, 22–24 March 2019. Neuromuscul Disord 2019; 29:725-733. [DOI: 10.1016/j.nmd.2019.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 08/13/2019] [Indexed: 01/13/2023]
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20
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Aryaman J, Bowles C, Jones NS, Johnston IG. Mitochondrial Network State Scales mtDNA Genetic Dynamics. Genetics 2019; 212:1429-1443. [PMID: 31253641 PMCID: PMC6707450 DOI: 10.1534/genetics.119.302423] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 06/28/2019] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial DNA (mtDNA) mutations cause severe congenital diseases but may also be associated with healthy aging. mtDNA is stochastically replicated and degraded, and exists within organelles which undergo dynamic fusion and fission. The role of the resulting mitochondrial networks in the time evolution of the cellular proportion of mutated mtDNA molecules (heteroplasmy), and cell-to-cell variability in heteroplasmy (heteroplasmy variance), remains incompletely understood. Heteroplasmy variance is particularly important since it modulates the number of pathological cells in a tissue. Here, we provide the first wide-reaching theoretical framework which bridges mitochondrial network and genetic states. We show that, under a range of conditions, the (genetic) rate of increase in heteroplasmy variance and de novo mutation are proportionally modulated by the (physical) fraction of unfused mitochondria, independently of the absolute fission-fusion rate. In the context of selective fusion, we show that intermediate fusion:fission ratios are optimal for the clearance of mtDNA mutants. Our findings imply that modulating network state, mitophagy rate, and copy number to slow down heteroplasmy dynamics when mean heteroplasmy is low could have therapeutic advantages for mitochondrial disease and healthy aging.
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Affiliation(s)
- Juvid Aryaman
- Department of Mathematics, Imperial College London, SW7 2AZ, United Kingdom
- Department of Clinical Neurosciences, University of Cambridge, CB2 0QQ, United Kingdom
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, CB2 0XY, United Kingdom
| | - Charlotte Bowles
- School of Biosciences, University of Birmingham, B15 2TT, United Kingdom
| | - Nick S Jones
- Department of Mathematics, Imperial College London, SW7 2AZ, United Kingdom
- Engineering and Physical Sciences Research Council Centre for the Mathematics of Precision Healthcare, Imperial College London, SW7 2AZ, United Kingdom
| | - Iain G Johnston
- Faculty of Mathematics and Natural Sciences, University of Bergen, 5007, Norway
- Alan Turing Institute, London NW1 2DB, United Kingdom
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21
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Hoitzing H, Gammage PA, Haute LV, Minczuk M, Johnston IG, Jones NS. Energetic costs of cellular and therapeutic control of stochastic mitochondrial DNA populations. PLoS Comput Biol 2019; 15:e1007023. [PMID: 31242175 PMCID: PMC6615642 DOI: 10.1371/journal.pcbi.1007023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 07/09/2019] [Accepted: 04/11/2019] [Indexed: 12/28/2022] Open
Abstract
The dynamics of the cellular proportion of mutant mtDNA molecules is crucial for mitochondrial diseases. Cellular populations of mitochondria are under homeostatic control, but the details of the control mechanisms involved remain elusive. Here, we use stochastic modelling to derive general results for the impact of cellular control on mtDNA populations, the cost to the cell of different mtDNA states, and the optimisation of therapeutic control of mtDNA populations. This formalism yields a wealth of biological results, including that an increasing mtDNA variance can increase the energetic cost of maintaining a tissue, that intermediate levels of heteroplasmy can be more detrimental than homoplasmy even for a dysfunctional mutant, that heteroplasmy distribution (not mean alone) is crucial for the success of gene therapies, and that long-term rather than short intense gene therapies are more likely to beneficially impact mtDNA populations.
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Affiliation(s)
- Hanne Hoitzing
- Department of Mathematics, Imperial College London, London, SW7 2AZ, United Kingdom
| | - Payam A. Gammage
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 0XY, United Kingdom
- CRUK Beatson Institute for Cancer Research, Glasgow, United Kingdom
| | - Lindsey Van Haute
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 0XY, United Kingdom
| | - Michal Minczuk
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 0XY, United Kingdom
| | - Iain G. Johnston
- Faculty of Mathematics and Natural Sciences, University of Bergen, Bergen, Norway
- Alan Turing Institute, London, United Kingdom
| | - Nick S. Jones
- Department of Mathematics, Imperial College London, London, SW7 2AZ, United Kingdom
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22
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Pan J, Wang L, Lu C, Zhu Y, Min Z, Dong X, Sha H. Matching Mitochondrial DNA Haplotypes for Circumventing Tissue-Specific Segregation Bias. iScience 2019; 13:371-379. [PMID: 30897510 PMCID: PMC6426714 DOI: 10.1016/j.isci.2019.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/13/2019] [Accepted: 03/01/2019] [Indexed: 02/01/2023] Open
Abstract
Mitochondrial DNA (mtDNA) segregation associated with donor-recipient mtDNA mismatch in mitochondria replacement therapy leads to unknown risks. Here, to explore whether matching mtDNA haplotypes contributes to ameliorating segregation, we reproduced various degrees of heteroplasmic mice with three single nucleotide polymorphisms to monitor segregation severity. “Segregation” presented in tissues of heteroplasmic mice containing low-level donor mtDNA heteroplasmy, and disappeared as donor mtDNA heteroplasmy levels ascended. Meanwhile, we found that distribution of donor mtDNA among the blastomeres of preimplantation embryos from the heteroplasmic mice shared the same tendency as that in adult tissues. Statistical analysis showed that no selective replication of donor mtDNA occurred during lifespan. Tracking donor mtDNA distribution showed that uneven distribution of donor mtDNA among embryonic blastomeres gradually became even as donor mtDNA heteroplasmy increased, indicating that the “segregation” in tissues was inherited from the uneven distribution. Our finding suggested that donor-recipient mtDNA matching could circumvent segregation in mitochondria replacement therapy. Matching mitochondrial DNA haplotypes make the nucleus treat different mtDNA the same Similar mtDNA haplotypes prevents tissue-specific segregation bias Low level of mtDNA heteroplasmy results in uneven inheritance rather than segregation
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Affiliation(s)
- Jianxin Pan
- Reproductive Medicine Center, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Li Wang
- Key Lab of Synthetic Biology of CAS, Shanghai Institute for Biological Sciences, Shanghai Research Center of Biotech., Chinese Academy of Sciences, 500 Caobao Road, Shanghai 200233, China
| | - Charles Lu
- Reproductive Medicine Center, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai 200032, China; Washington University in St. Louis, Saint Louis 63110, USA
| | - Yanming Zhu
- Reproductive Medicine Center, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhunyuan Min
- Reproductive Medicine Center, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xi Dong
- Reproductive Medicine Center, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai 200032, China.
| | - Hongying Sha
- Reproductive Medicine Center, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, Shanghai 200032, China.
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23
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Miyaue N, Yamanishi Y, Tada S, Ando R, Nagai M, Nomoto M. Falling After Starting Running in a Case of Myoclonus Epilepsy Associated with Ragged-red Fibers with a 8344A>G mtDNA Mutation. Intern Med 2018; 57:3439-3443. [PMID: 29984755 PMCID: PMC6306540 DOI: 10.2169/internalmedicine.1210-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Myoclonus epilepsy associated with ragged-red fibers (MERRF) is traditionally characterized by myoclonus, generalized epilepsy and ragged-red fibers. We herein report a 42-year-old man who complained of falling after starting running, symptoms resembling those of paroxysmal kinesigenic dyskinesia. He showed only slight muscle weakness of the right quadriceps femoris. Muscle pathology and a genetic analysis identified him as having MERRF with a 8344A>G mtDNA mutation. We diagnosed his symptoms as having been caused by slight quadriceps femoris muscle weakness and exercise intolerance. This case suggests that mitochondrial myopathy should be considered in cases with strong muscle symptoms for muscle weakness.
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Affiliation(s)
- Noriyuki Miyaue
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Japan
| | - Yuki Yamanishi
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Japan
| | - Satoshi Tada
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Japan
| | - Rina Ando
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Japan
| | - Masahiro Nagai
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Japan
| | - Masahiro Nomoto
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Japan
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24
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Burgstaller JP, Kolbe T, Havlicek V, Hembach S, Poulton J, Piálek J, Steinborn R, Rülicke T, Brem G, Jones NS, Johnston IG. Large-scale genetic analysis reveals mammalian mtDNA heteroplasmy dynamics and variance increase through lifetimes and generations. Nat Commun 2018; 9:2488. [PMID: 29950599 PMCID: PMC6021422 DOI: 10.1038/s41467-018-04797-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/22/2018] [Indexed: 11/30/2022] Open
Abstract
Vital mitochondrial DNA (mtDNA) populations exist in cells and may consist of heteroplasmic mixtures of mtDNA types. The evolution of these heteroplasmic populations through development, ageing, and generations is central to genetic diseases, but is poorly understood in mammals. Here we dissect these population dynamics using a dataset of unprecedented size and temporal span, comprising 1947 single-cell oocyte and 899 somatic measurements of heteroplasmy change throughout lifetimes and generations in two genetically distinct mouse models. We provide a novel and detailed quantitative characterisation of the linear increase in heteroplasmy variance throughout mammalian life courses in oocytes and pups. We find that differences in mean heteroplasmy are induced between generations, and the heteroplasmy of germline and somatic precursors diverge early in development, with a haplotype-specific direction of segregation. We develop stochastic theory predicting the implications of these dynamics for ageing and disease manifestation and discuss its application to human mtDNA dynamics.
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Affiliation(s)
- Joerg P Burgstaller
- Department for Agrobiotechnology, Biotechnology in Animal Production, IFA Tulln, 3430, Tulln, Austria.
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria.
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK.
| | - Thomas Kolbe
- Biomodels Austria, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210, Vienna, Austria
- University of Natural Resources and Life Sciences, Konrad Lorenz Strasse 20, 3430, Tulln, Austria
| | - Vitezslav Havlicek
- Department for Biomedical Sciences, Reproduction Centre Wieselburg, University of Veterinary Medicine, Vienna, Austria
| | - Stephanie Hembach
- Department for Agrobiotechnology, Biotechnology in Animal Production, IFA Tulln, 3430, Tulln, Austria
| | - Joanna Poulton
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, United Kingdom
| | - Jaroslav Piálek
- Research Facility Studenec, Institute of Vertebrate Biology of the Czech Academy of Sciences, Květná 8, 603 65, Brno, Czech Republic
| | - Ralf Steinborn
- Genomics Core Facility, VetCore, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Thomas Rülicke
- Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Gottfried Brem
- Department for Agrobiotechnology, Biotechnology in Animal Production, IFA Tulln, 3430, Tulln, Austria
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Nick S Jones
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK.
- EPSRC Centre for the Mathematics of Precision Healthcare, Imperial College London, London, SW7 2AZ, UK.
| | - Iain G Johnston
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK.
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Cecchino GN, Seli E, Alves da Motta EL, García-Velasco JA. The role of mitochondrial activity in female fertility and assisted reproductive technologies: overview and current insights. Reprod Biomed Online 2018; 36:686-697. [DOI: 10.1016/j.rbmo.2018.02.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 02/18/2018] [Accepted: 02/28/2018] [Indexed: 12/21/2022]
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26
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Poulton J, Finsterer J, Yu-Wai-Man P. Genetic Counselling for Maternally Inherited Mitochondrial Disorders. Mol Diagn Ther 2018; 21:419-429. [PMID: 28536827 DOI: 10.1007/s40291-017-0279-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The aim of this review was to provide an evidence-based approach to frequently asked questions relating to the risk of transmitting a maternally inherited mitochondrial disorder (MID). We do not address disorders linked with disturbed mitochondrial DNA (mtDNA) maintenance, causing mtDNA depletion or multiple mtDNA deletions, as these are autosomally inherited. The review addresses questions regarding prognosis, recurrence risks and the strategies available to prevent disease transmission. The clinical and genetic complexity of maternally inherited MIDs represent a major challenge for patients, their relatives and health professionals. Since many of the genetic and pathophysiological aspects of MIDs remain unknown, counselling of affected patients and at-risk family members remains difficult. MtDNA mutations are maternally transmitted or, more rarely, they are sporadic, occurring de novo (~25%). Females carrying homoplasmic mtDNA mutations will transmit the mutant species to all of their offspring, who may or may not exhibit a similar phenotype depending on modifying, secondary factors. Females carrying heteroplasmic mtDNA mutations will transmit a variable amount of mutant mtDNA to their offspring, which can result in considerable phenotypic heterogeneity among siblings. The majority of mtDNA rearrangements, such as single large-scale deletions, are sporadic, but there is a small risk of recurrence (~4%) among the offspring of affected women. The range and suitability of reproductive choices for prospective mothers is a complex area of mitochondrial medicine that needs to be managed by experienced healthcare professionals as part of a multidisciplinary team. Genetic counselling is facilitated by the identification of the underlying causative genetic defect. To provide more precise genetic counselling, further research is needed to clarify the secondary factors that account for the variable penetrance and the often marked differential expressivity of pathogenic mtDNA mutations both within and between families.
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Affiliation(s)
- Joanna Poulton
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Oxford, UK
| | - Josef Finsterer
- Krankenanstalt Rudolfstiftung, Postfach 20, 1180, Vienna, Austria.
| | - Patrick Yu-Wai-Man
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK.,Newcastle Eye Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK.,NIHR Biomedical Research Centre, Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK.,Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
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27
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Craven L, Tang MX, Gorman GS, De Sutter P, Heindryckx B. Novel reproductive technologies to prevent mitochondrial disease. Hum Reprod Update 2018. [PMID: 28651360 DOI: 10.1093/humupd/dmx018] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The use of nuclear transfer (NT) has been proposed as a novel reproductive treatment to overcome the transmission of maternally-inherited mitochondrial DNA (mtDNA) mutations. Pathogenic mutations in mtDNA can cause a wide-spectrum of life-limiting disorders, collectively known as mtDNA disease, for which there are currently few effective treatments and no known cures. The many unique features of mtDNA make genetic counselling challenging for women harbouring pathogenic mtDNA mutations but reproductive options that involve medical intervention are available that will minimize the risk of mtDNA disease in their offspring. This includes PGD, which is currently offered as a clinical treatment but will not be suitable for all. The potential for NT to reduce transmission of mtDNA mutations has been demonstrated in both animal and human models, and has recently been clinically applied not only to prevent mtDNA disease but also for some infertility cases. In this review, we will interrogate the different NT techniques, including a discussion on the available safety and efficacy data of these technologies for mtDNA disease prevention. In addition, we appraise the evidence for the translational use of NT technologies in infertility. OBJECTIVE AND RATIONALE We propose to review the current scientific evidence regarding the clinical use of NT to prevent mitochondrial disease. SEARCH METHODS The scientific literature was investigated by searching PubMed database until Jan 2017. Relevant documents from Human Fertilisation and Embryology Authority as well as reports from both the scientific and popular media were also implemented. The above searches were based on the following key words: 'mitochondria', 'mitochondrial DNA'; 'mitochondrial DNA disease', 'fertility'; 'preimplantation genetic diagnosis', 'nuclear transfer', 'mitochondrial replacement' and 'mitochondrial donation'. OUTCOMES While NT techniques have been shown to effectively reduce the transmission of heteroplasmic mtDNA variants in animal models, and increasing evidence supports their use to prevent the transmission of human mtDNA disease, the need for robust, long-term evaluation is still warranted. Moreover, prenatal screening would still be strongly advocated in combination with the use of these IVF-based technologies. Scientific evidence to support the use of NT and other novel reproductive techniques for infertility is currently lacking. WIDER IMPLICATIONS It is mandatory that any new ART treatments are first adequately assessed in both animal and human models before the cautious implementation of these new therapeutic approaches is clinically undertaken. There is growing evidence to suggest that the translation of these innovative technologies into clinical practice should be cautiously adopted only in highly selected patients. Indeed, given the limited safety and efficacy data, close monitoring of any offspring remains paramount.
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Affiliation(s)
- Lyndsey Craven
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Mao-Xing Tang
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Gráinne S Gorman
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Petra De Sutter
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Björn Heindryckx
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
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Lima A, Burgstaller J, Sanchez-Nieto JM, Rodríguez TA. The Mitochondria and the Regulation of Cell Fitness During Early Mammalian Development. Curr Top Dev Biol 2017; 128:339-363. [PMID: 29477168 DOI: 10.1016/bs.ctdb.2017.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
From fertilization until the onset of gastrulation the early mammalian embryo undergoes a dramatic series of changes that converts a single fertilized cell into a remarkably complex organism. Much attention has been given to the molecular changes occurring during this process, but here we will review what is known about the changes affecting the mitochondria and how they impact on the energy metabolism and apoptotic response of the embryo. We will also focus on understanding what quality control mechanisms ensure optimal mitochondrial activity in the embryo, and in this way provide an overview of the importance of the mitochondria in determining cell fitness during early mammalian development.
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Affiliation(s)
- Ana Lima
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom; Cell Stress Group, MRC London Institute of Medical Sciences (LMS), London, United Kingdom
| | - Jörg Burgstaller
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom; Biotechnology in Animal Production, Department for Agrobiotechnology, IFA Tulln, Tulln, Austria
| | - Juan M Sanchez-Nieto
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom
| | - Tristan A Rodríguez
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom.
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29
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Pan Z, Usui H, Sato A, Shozu M. Complete hydatidiform moles are composed of paternal chromosomes and maternal mitochondria. Mitochondrial DNA A DNA Mapp Seq Anal 2017; 29:943-950. [PMID: 29037102 DOI: 10.1080/24701394.2017.1389916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Mitochondrial DNA (mtDNA) and genomic DNA are produced in separate subcellular compartments. Human mtDNA is transmitted via maternal transmission in general. Complete hydatidiform moles (CHMs) represent major trophoblastic diseases that are cytogenetically exceptional because the chromosomal genomic DNA is derived only from sperm cells, making them strikingly different from normal concepti. However, few reports have described the mtDNA-transmission pattern in hydatidiform moles. To evaluate mtDNA transmission in androgenetic CHMs, we compared the sequences of hypervariable regions in 16 trios sets of mtDNAs from maternal, paternal, and villous samples of androgenetic CHMs diagnosed by short tandem repeat-polymorphism analysis. All mtDNAs in androgenetic CHMs were maternally derived, in line with the general human inheritance pattern. Three maternal mtDNAs were heteroplasmic. The heterozygous status of maternal mtDNA was reflected in villous tissue, in which variants status was also heterozygous. CHMs are composed of paternal chromosomes and maternal mitochondria.
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Affiliation(s)
- Zijun Pan
- a Department of Reproductive Medicine , Graduate School of Medicine, Chiba University , Chiba , Japan
| | - Hirokazu Usui
- a Department of Reproductive Medicine , Graduate School of Medicine, Chiba University , Chiba , Japan
| | - Asuka Sato
- a Department of Reproductive Medicine , Graduate School of Medicine, Chiba University , Chiba , Japan
| | - Makio Shozu
- a Department of Reproductive Medicine , Graduate School of Medicine, Chiba University , Chiba , Japan
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30
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Modulating mitochondrial quality in disease transmission: towards enabling mitochondrial DNA disease carriers to have healthy children. Biochem Soc Trans 2017; 44:1091-100. [PMID: 27528757 PMCID: PMC4984448 DOI: 10.1042/bst20160095] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Indexed: 12/19/2022]
Abstract
One in 400 people has a maternally inherited mutation in mtDNA potentially causing incurable disease. In so-called heteroplasmic disease, mutant and normal mtDNA co-exist in the cells of carrier women. Disease severity depends on the proportion of inherited abnormal mtDNA molecules. Families who have had a child die of severe, maternally inherited mtDNA disease need reliable information on the risk of recurrence in future pregnancies. However, prenatal diagnosis and even estimates of risk are fraught with uncertainty because of the complex and stochastic dynamics of heteroplasmy. These complications include an mtDNA bottleneck, whereby hard-to-predict fluctuations in the proportions of mutant and normal mtDNA may arise between generations. In ‘mitochondrial replacement therapy’ (MRT), damaged mitochondria are replaced with healthy ones in early human development, using nuclear transfer. We are developing non-invasive alternatives, notably activating autophagy, a cellular quality control mechanism, in which damaged cellular components are engulfed by autophagosomes. This approach could be used in combination with MRT or with the regular management, pre-implantation genetic diagnosis (PGD). Mathematical theory, supported by recent experiments, suggests that this strategy may be fruitful in controlling heteroplasmy. Using mice that are transgenic for fluorescent LC3 (the hallmark of autophagy) we quantified autophagosomes in cleavage stage embryos. We confirmed that the autophagosome count peaks in four-cell embryos and this correlates with a drop in the mtDNA content of the whole embryo. This suggests removal by mitophagy (mitochondria-specific autophagy). We suggest that modulating heteroplasmy by activating mitophagy may be a useful complement to mitochondrial replacement therapy.
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31
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Caicedo A, Aponte PM, Cabrera F, Hidalgo C, Khoury M. Artificial Mitochondria Transfer: Current Challenges, Advances, and Future Applications. Stem Cells Int 2017; 2017:7610414. [PMID: 28751917 PMCID: PMC5511681 DOI: 10.1155/2017/7610414] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/30/2017] [Accepted: 05/15/2017] [Indexed: 12/18/2022] Open
Abstract
The objective of this review is to outline existing artificial mitochondria transfer techniques and to describe the future steps necessary to develop new therapeutic applications in medicine. Inspired by the symbiotic origin of mitochondria and by the cell's capacity to transfer these organelles to damaged neighbors, many researchers have developed procedures to artificially transfer mitochondria from one cell to another. The techniques currently in use today range from simple coincubations of isolated mitochondria and recipient cells to the use of physical approaches to induce integration. These methods mimic natural mitochondria transfer. In order to use mitochondrial transfer in medicine, we must answer key questions about how to replicate aspects of natural transport processes to improve current artificial transfer methods. Another priority is to determine the optimum quantity and cell/tissue source of the mitochondria in order to induce cell reprogramming or tissue repair, in both in vitro and in vivo applications. Additionally, it is important that the field explores how artificial mitochondria transfer techniques can be used to treat different diseases and how to navigate the ethical issues in such procedures. Without a doubt, mitochondria are more than mere cell power plants, as we continue to discover their potential to be used in medicine.
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Affiliation(s)
- Andrés Caicedo
- Colegio de Ciencias de la Salud, Escuela de Medicina, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Colegio de Ciencias Biológicas y Ambientales, Instituto de Microbiología, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Mito-Act Research Consortium, Quito, Ecuador
| | - Pedro M. Aponte
- Mito-Act Research Consortium, Quito, Ecuador
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
| | - Francisco Cabrera
- Mito-Act Research Consortium, Quito, Ecuador
- Colegio de Ciencias de la Salud, Escuela de Medicina Veterinaria, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Institute for Regenerative Medicine and Biotherapy (IRMB), INSERM U1183, 2 Montpellier University, Montpellier, France
| | - Carmen Hidalgo
- Mito-Act Research Consortium, Quito, Ecuador
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile
| | - Maroun Khoury
- Mito-Act Research Consortium, Quito, Ecuador
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile
- Consorcio Regenero, Chilean Consortium for Regenerative Medicine, Santiago, Chile
- Cells for Cells, Santiago, Chile
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32
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Abstract
Background Cattle are bred for, amongst other factors, specific traits, including parasite resistance and adaptation to climate. However, the influence and inheritance of mitochondrial DNA (mtDNA) are not usually considered in breeding programmes. In this study, we analysed the mtDNA profiles of cattle from Victoria (VIC), southern Australia, which is a temperate climate, and the Northern Territory (NT), the northern part of Australia, which has a tropical climate, to determine if the mtDNA profiles of these cattle are indicative of breed and phenotype, and whether these profiles are appropriate for their environments. Results A phylogenetic tree of the full mtDNA sequences of different breeds of cattle, which were obtained from the NCBI database, showed that the mtDNA profiles of cattle do not always reflect their phenotype as some cattle with Bos taurus phenotypes had Bos indicus mtDNA, whilst some cattle with Bos indicus phenotypes had Bos taurus mtDNA. Using D-loop sequencing, we were able to contrast the phenotypes and mtDNA profiles from different species of cattle from the 2 distinct cattle breeding regions of Australia. We found that 67 of the 121 cattle with Bos indicus phenotypes from NT (55.4%) had Bos taurus mtDNA. In VIC, 92 of the 225 cattle with Bos taurus phenotypes (40.9%) possessed Bos indicus mtDNA. When focusing on oocytes from cattle with the Bos taurus phenotype in VIC, their respective oocytes with Bos indicus mtDNA had significantly lower levels of mtDNA copy number compared with oocytes possessing Bos taurus mtDNA (P < 0.01). However, embryos derived from oocytes with Bos indicus mtDNA had the same ability to develop to the blastocyst stage and the levels of mtDNA copy number in their blastocysts were similar to blastocysts derived from oocytes harbouring Bos taurus mtDNA. Nevertheless, oocytes originating from the Bos indicus phenotype exhibited lower developmental potential due to low mtDNA copy number when compared with oocytes from cattle with a Bos taurus phenotype. Conclusions The phenotype of cattle is not always related to their mtDNA profiles. MtDNA profiles should be considered for breeding programmes as they also influence phenotypic traits and reproductive capacity in terms of oocyte quality. Electronic supplementary material The online version of this article (doi:10.1186/s12863-017-0523-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kanokwan Srirattana
- Centre for Genetic Diseases, Hudson Institute of Medical Research, Clayton, VIC, 3168, Australia.,Department of Molecular and Translational Sciences, Monash University, Clayton, VIC, 3168, Australia
| | - Kieren McCosker
- Department of Primary Industry and Resources, Darwin, NT, 0800, Australia
| | - Tim Schatz
- Department of Primary Industry and Resources, Darwin, NT, 0800, Australia
| | - Justin C St John
- Centre for Genetic Diseases, Hudson Institute of Medical Research, Clayton, VIC, 3168, Australia. .,Department of Molecular and Translational Sciences, Monash University, Clayton, VIC, 3168, Australia.
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33
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No difference in mitochondrial distribution is observed in human oocytes after cryopreservation. Arch Gynecol Obstet 2017. [DOI: 10.1007/s00404-017-4428-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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34
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Colijn C, Jones N, Johnston IG, Yaliraki S, Barahona M. Toward Precision Healthcare: Context and Mathematical Challenges. Front Physiol 2017; 8:136. [PMID: 28377724 PMCID: PMC5359292 DOI: 10.3389/fphys.2017.00136] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 02/22/2017] [Indexed: 12/12/2022] Open
Abstract
Precision medicine refers to the idea of delivering the right treatment to the right patient at the right time, usually with a focus on a data-centered approach to this task. In this perspective piece, we use the term "precision healthcare" to describe the development of precision approaches that bridge from the individual to the population, taking advantage of individual-level data, but also taking the social context into account. These problems give rise to a broad spectrum of technical, scientific, policy, ethical and social challenges, and new mathematical techniques will be required to meet them. To ensure that the science underpinning "precision" is robust, interpretable and well-suited to meet the policy, ethical and social questions that such approaches raise, the mathematical methods for data analysis should be transparent, robust, and able to adapt to errors and uncertainties. In particular, precision methodologies should capture the complexity of data, yet produce tractable descriptions at the relevant resolution while preserving intelligibility and traceability, so that they can be used by practitioners to aid decision-making. Through several case studies in this domain of precision healthcare, we argue that this vision requires the development of new mathematical frameworks, both in modeling and in data analysis and interpretation.
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Affiliation(s)
- Caroline Colijn
- Department of Mathematics, Imperial College LondonLondon, UK
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College LondonLondon, UK
| | - Nick Jones
- Department of Mathematics, Imperial College LondonLondon, UK
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College LondonLondon, UK
| | - Iain G. Johnston
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College LondonLondon, UK
- School of Biosciences, University of BirminghamBirmingham, UK
| | - Sophia Yaliraki
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College LondonLondon, UK
- Department of Chemistry, Imperial College LondonLondon, UK
| | - Mauricio Barahona
- Department of Mathematics, Imperial College LondonLondon, UK
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College LondonLondon, UK
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35
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Affiliation(s)
- Tetsuya Ishii
- Office of Health and Safety; Hokkaido University; Hokkaido Japan
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36
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Kang E, Wu J, Gutierrez NM, Koski A, Tippner-Hedges R, Agaronyan K, Platero-Luengo A, Martinez-Redondo P, Ma H, Lee Y, Hayama T, Van Dyken C, Wang X, Luo S, Ahmed R, Li Y, Ji D, Kayali R, Cinnioglu C, Olson S, Jensen J, Battaglia D, Lee D, Wu D, Huang T, Wolf DP, Temiakov D, Belmonte JCI, Amato P, Mitalipov S. Mitochondrial replacement in human oocytes carrying pathogenic mitochondrial DNA mutations. Nature 2016; 540:270-275. [PMID: 27919073 DOI: 10.1038/nature20592] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 11/02/2016] [Indexed: 12/17/2022]
Abstract
Maternally inherited mitochondrial (mt)DNA mutations can cause fatal or severely debilitating syndromes in children, with disease severity dependent on the specific gene mutation and the ratio of mutant to wild-type mtDNA (heteroplasmy) in each cell and tissue. Pathogenic mtDNA mutations are relatively common, with an estimated 778 affected children born each year in the United States. Mitochondrial replacement therapies or techniques (MRT) circumventing mother-to-child mtDNA disease transmission involve replacement of oocyte maternal mtDNA. Here we report MRT outcomes in several families with common mtDNA syndromes. The mother's oocytes were of normal quality and mutation levels correlated with those in existing children. Efficient replacement of oocyte mutant mtDNA was performed by spindle transfer, resulting in embryos containing >99% donor mtDNA. Donor mtDNA was stably maintained in embryonic stem cells (ES cells) derived from most embryos. However, some ES cell lines demonstrated gradual loss of donor mtDNA and reversal to the maternal haplotype. In evaluating donor-to-maternal mtDNA interactions, it seems that compatibility relates to mtDNA replication efficiency rather than to mismatch or oxidative phosphorylation dysfunction. We identify a polymorphism within the conserved sequence box II region of the D-loop as a plausible cause of preferential replication of specific mtDNA haplotypes. In addition, some haplotypes confer proliferative and growth advantages to cells. Hence, we propose a matching paradigm for selecting compatible donor mtDNA for MRT.
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Affiliation(s)
- Eunju Kang
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Jun Wu
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Nuria Marti Gutierrez
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Amy Koski
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Rebecca Tippner-Hedges
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Karen Agaronyan
- Department of Cell Biology School of Osteopathic Medicine, Rowan University, 2 Medical Center Drive, Stratford, New Jersey 08084, USA
| | - Aida Platero-Luengo
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Paloma Martinez-Redondo
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Hong Ma
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Yeonmi Lee
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Tomonari Hayama
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Crystal Van Dyken
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Xinjian Wang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA
| | - Shiyu Luo
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA
| | - Riffat Ahmed
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Ying Li
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Dongmei Ji
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Reproductive Medical Centre, Anhui Medical University, No 218, Jixi Rd, Shushan District, Heifei, Anhui 230022, China
| | - Refik Kayali
- IviGen Los Angeles, 406 Amapola Avenue, Suite 215, Torrance, California 90501, USA
| | - Cengiz Cinnioglu
- IviGen Los Angeles, 406 Amapola Avenue, Suite 215, Torrance, California 90501, USA
| | - Susan Olson
- Research Cytogenetics Laboratory, Oregon Health &Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA
| | - Jeffrey Jensen
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA
| | - David Battaglia
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA
| | - David Lee
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA
| | - Diana Wu
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio 45229, USA
| | - Don P Wolf
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA
| | - Dmitry Temiakov
- Department of Cell Biology School of Osteopathic Medicine, Rowan University, 2 Medical Center Drive, Stratford, New Jersey 08084, USA
| | - Juan Carlos Izpisua Belmonte
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Paula Amato
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA
| | - Shoukhrat Mitalipov
- Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 NW 185th Avenue, Beaverton, Oregon 97006, USA.,Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA.,Knight Cardiovascular Institute, Oregon Health &Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA.,Department of Biomedical Engineering, Oregon Health &Science University, 3303 SW Bond Avenue, Portland, Oregon 97239, USA
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37
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Evolution of Cell-to-Cell Variability in Stochastic, Controlled, Heteroplasmic mtDNA Populations. Am J Hum Genet 2016; 99:1150-1162. [PMID: 27843124 DOI: 10.1016/j.ajhg.2016.09.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 09/22/2016] [Indexed: 11/20/2022] Open
Abstract
Populations of physiologically vital mitochondrial DNA (mtDNA) molecules evolve in cells under control from the nucleus. The evolution of populations of mixed mtDNA types is complicated and poorly understood, and variability of these controlled admixtures plays a central role in the inheritance and onset of genetic disease. Here, we develop a mathematical theory describing the evolution of, and variability in, these stochastic populations for any type of cellular control, showing that cell-to-cell variability in mtDNA and mutant load inevitably increases with time, according to rates that we derive and which are notably independent of the mechanistic details of feedback signaling. We show with a set of experimental case studies that this theory explains disparate quantitative results from classical and modern experimental and computational research on heteroplasmy variance in different species. We demonstrate that our general model provides a host of specific insights, including a modification of the often-used but hard-to-interpret Wright formula to correspond directly to biological observables, the ability to quantify selective and mutational pressure in mtDNA populations, and characterization of the pronounced variability inevitably arising from the action of possible mtDNA quality-control mechanisms. Our general theoretical framework, supported by existing experimental results, thus helps us to understand and predict the evolution of stochastic mtDNA populations in cell biology.
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38
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Reznichenko AS, Huyser C, Pepper MS. Mitochondrial transfer: Implications for assisted reproductive technologies. Appl Transl Genom 2016; 11:40-47. [PMID: 28018848 PMCID: PMC5167373 DOI: 10.1016/j.atg.2016.10.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 10/05/2016] [Accepted: 10/14/2016] [Indexed: 01/24/2023]
Abstract
The use of mitochondrial transfer as a clinic procedure is drawing closer to reality. Here we provide a detailed overview of mitochondrial transfer techniques – both established and recent – including pronuclear, spindle, ooplasmic and blastomere transfer. Reasons as to why some techniques are more suitable for the prevention of mitochondrial DNA disease than others, as well as the advantages and disadvantages of each methodology, are discussed. The possible clinical introduction of these techniques has raised concerns about the adverse effects they may have on resultant embryos and offspring. Success rates of each technique, embryo viability and developmental consequences post mitochondrial transfer are addressed through analysis of evidence obtained from both animal and human studies. Counterarguments against potential mitochondrial-nuclear genome incompatibility are also provided. Additional clinical applications of mitochondrial transfer techniques are discussed. These include the rescue or enhancement of fertility in women of advanced maternal age or those suffering from diabetes. An alternative to using mitochondrial DNA transfer for germ line therapies is the therapeutic use of somatic cell nuclear transfer for the generation of personalised stem cells. Although ethically challenging, this method could offer patients already suffering from mitochondrial DNA diseases a novel treatment option.
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Affiliation(s)
- A S Reznichenko
- IVF Laboratory, Medfem Fertility Clinic, Bryanston, South Africa
| | - C Huyser
- Department of Obstetrics and Gynaecology, University of Pretoria, Steve Biko Academic Hospital, Pretoria, South Africa
| | - M S Pepper
- Department of Immunology and Institute for Cellular and Molecular Medicine, and SAMRC Extramural Unit doe Stem Cell Research and Therapy, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
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39
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Røyrvik EC, Burgstaller JP, Johnston IG. mtDNA diversity in human populations highlights the merit of haplotype matching in gene therapies. Mol Hum Reprod 2016; 22:809-817. [PMID: 27609757 DOI: 10.1093/molehr/gaw062] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 09/02/2016] [Indexed: 12/20/2022] Open
Abstract
STUDY QUESTION Does mitochondrial DNA (mtDNA) diversity in modern human populations potentially pose a challenge, via mtDNA segregation, to mitochondrial replacement therapies? SUMMARY ANSWER The magnitude of mtDNA diversity in modern human populations is as high as in mammalian model systems where strong mtDNA segregation is observed; consideration of haplotype pairs and/or haplotype matching can help avoid these potentially deleterious effects. WHAT IS KNOWN ALREADY In mammalian models, substantial proliferative differences are observed between different mtDNA haplotypes in cellular admixtures, with larger proliferative differences arising from more diverse haplotype pairings. If maternal mtDNA is 'carried over' in human gene therapies, these proliferative differences could lead to its amplification in the resulting offspring, potentially leading to manifestation of the disease that the therapy was designed to avoid-but existing studies have not investigated whether mtDNA diversity in modern human populations is sufficient to permit significant amplification. STUDY DESIGN, SIZE, DURATION This theoretical study used over 7500 human mtDNA sequences from The National Center for Biotechnology Information (NCBI), a range of international and British mtDNA surveys, and 2011 census data. PARTICIPANTS/MATERIALS, SETTING, METHODS A stochastic simulation approach was used to model random haplotype pairings from within different regions. In total, 1000 simulated pairings were analysed using the basic local alignment search tool (BLAST) for each region. Previous data from mouse models were used to estimate proliferative differences. MAIN RESULTS AND THE ROLE OF CHANCE Even within the same haplogroup, differences of around 20-80 single-nucleotide polymorphisms (SNPs) are common between mtDNAs admixed in random pairings. These values are sufficient to lead to substantial segregation in mouse models over an organismal lifetime, even given low starting heteroplasmy, inducing increases from 5% to 35% over 1 year. Substantial population mixing in modern UK cities increases the expected genetic differences. Hence, the likely genetic differences between humans randomly sampled from a population may well allow substantial amplification of a disease-carrying mtDNA haplotype over the timescale of a human lifetime. We report ranges and mean differences for all statistics to quantify uncertainty in our results. LIMITATIONS/REASONS FOR CAUTION The mapping from mouse and other mammalian models to the human system is challenging, as timescales and mechanisms may differ. Reporting biases in NCBI mtDNA data, if present, may affect the statistics we compute. We discuss the robustness of our findings in the light of these concerns. WIDER IMPLICATIONS OF THE FINDINGS Matching the mtDNA haplotypes of the mother and third-party donor in mitochondrial replacement therapies is supported as a means of ameliorating the potentially deleterious results of human mtDNA diversity. We present a chart of expected SNP differences between mtDNA haplogroups, allowing the selection of optimal partners for therapies. LARGE SCALE DATA N/A STUDY FUNDING/COMPETING INTERESTS: The authors report no external funding sources or conflicts of interest.
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Affiliation(s)
- E C Røyrvik
- Division of Biomedical Sciences, Warwick Medical School, Gibbet Hill Road, University of Warwick, Coventry CV4 7AL, UK
| | - J P Burgstaller
- Biotechnology in Animal Production, Department for Agrobiotechnology, IFA Tulln, 3430 Tulln, Austria.,Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna , Veterinärplatz 1, 1210 Vienna, Austria
| | - I G Johnston
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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40
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Picard M, Wallace DC, Burelle Y. The rise of mitochondria in medicine. Mitochondrion 2016; 30:105-16. [PMID: 27423788 PMCID: PMC5023480 DOI: 10.1016/j.mito.2016.07.003] [Citation(s) in RCA: 300] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 07/04/2016] [Accepted: 07/12/2016] [Indexed: 12/11/2022]
Abstract
Once considered exclusively the cell's powerhouse, mitochondria are now recognized to perform multiple essential functions beyond energy production, impacting most areas of cell biology and medicine. Since the emergence of molecular biology and the discovery of pathogenic mitochondrial DNA defects in the 1980's, research advances have revealed a number of common human diseases which share an underlying pathogenesis involving mitochondrial dysfunction. Mitochondria undergo function-defining dynamic shape changes, communicate with each other, regulate gene expression within the nucleus, modulate synaptic transmission within the brain, release molecules that contribute to oncogenic transformation and trigger inflammatory responses systemically, and influence the regulation of complex physiological systems. Novel mitopathogenic mechanisms are thus being uncovered across a number of medical disciplines including genetics, oncology, neurology, immunology, and critical care medicine. Increasing knowledge of the bioenergetic aspects of human disease has provided new opportunities for diagnosis, therapy, prevention, and in connecting various domains of medicine. In this article, we overview specific aspects of mitochondrial biology that have contributed to - and likely will continue to enhance the progress of modern medicine.
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Affiliation(s)
- Martin Picard
- Department of Psychiatry, Division of Behavioral Medicine, Columbia University Medical Center, New York, NY, USA; Department of Neurology and CTNI, H Houston Merritt Center, Columbia University Medical Center, New York, NY, USA.
| | - Douglas C Wallace
- The Center for Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia and Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yan Burelle
- Faculty of Pharmacy, Université de Montreal, Montreal, QC, Canada
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41
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Hyslop LA, Blakeley P, Craven L, Richardson J, Fogarty NME, Fragouli E, Lamb M, Wamaitha SE, Prathalingam N, Zhang Q, O'Keefe H, Takeda Y, Arizzi L, Alfarawati S, Tuppen HA, Irving L, Kalleas D, Choudhary M, Wells D, Murdoch AP, Turnbull DM, Niakan KK, Herbert M. Towards clinical application of pronuclear transfer to prevent mitochondrial DNA disease. Nature 2016; 534:383-6. [PMID: 27281217 PMCID: PMC5131843 DOI: 10.1038/nature18303] [Citation(s) in RCA: 202] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 05/03/2016] [Indexed: 12/11/2022]
Abstract
Mitochondrial DNA (mtDNA) mutations are maternally inherited and are associated with a broad range of debilitating and fatal diseases. Reproductive technologies designed to uncouple the inheritance of mtDNA from nuclear DNA may enable affected women to have a genetically related child with a greatly reduced risk of mtDNA disease. Here we report the first preclinical studies on pronuclear transplantation (PNT). Surprisingly, techniques used in proof-of-concept studies involving abnormally fertilized human zygotes were not well tolerated by normally fertilized zygotes. We have therefore developed an alternative approach based on transplanting pronuclei shortly after completion of meiosis rather than shortly before the first mitotic division. This promotes efficient development to the blastocyst stage with no detectable effect on aneuploidy or gene expression. After optimization, mtDNA carryover was reduced to <2% in the majority (79%) of PNT blastocysts. The importance of reducing carryover to the lowest possible levels is highlighted by a progressive increase in heteroplasmy in a stem cell line derived from a PNT blastocyst with 4% mtDNA carryover. We conclude that PNT has the potential to reduce the risk of mtDNA disease, but it may not guarantee prevention.
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Affiliation(s)
- Louise A Hyslop
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
- Newcastle Fertility Centre, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 4EP, UK
| | - Paul Blakeley
- The Francis Crick Institute, Human Embryo and Stem Cell Laboratory, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK
| | - Lyndsey Craven
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Jessica Richardson
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Norah M E Fogarty
- The Francis Crick Institute, Human Embryo and Stem Cell Laboratory, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK
| | - Elpida Fragouli
- Reprogenetics UK, Institute of Reproductive Sciences, Oxford Business Park North, Oxford OX4 2HW, UK
| | - Mahdi Lamb
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Sissy E Wamaitha
- The Francis Crick Institute, Human Embryo and Stem Cell Laboratory, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK
| | - Nilendran Prathalingam
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
- Newcastle Fertility Centre, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 4EP, UK
| | - Qi Zhang
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Hannah O'Keefe
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Yuko Takeda
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Lucia Arizzi
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
- Newcastle Fertility Centre, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 4EP, UK
| | - Samer Alfarawati
- Reprogenetics UK, Institute of Reproductive Sciences, Oxford Business Park North, Oxford OX4 2HW, UK
| | - Helen A Tuppen
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Laura Irving
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Dimitrios Kalleas
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
| | - Meenakshi Choudhary
- Newcastle Fertility Centre, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 4EP, UK
| | - Dagan Wells
- University of Oxford, Nuffield Department of Obstetrics and Gynaecology, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Alison P Murdoch
- Newcastle Fertility Centre, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 4EP, UK
| | - Douglass M Turnbull
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Kathy K Niakan
- The Francis Crick Institute, Human Embryo and Stem Cell Laboratory, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK
| | - Mary Herbert
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 3BZ, UK
- Newcastle Fertility Centre, Biomedicine West Wing, Centre for Life, Times Square, Newcastle upon Tyne NE1 4EP, UK
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42
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Park HJ, Min SH, Choi H, Park J, Kim SU, Lee S, Lee SR, Kong IK, Chang KT, Koo DB, Lee DS. Mitochondria-targeted DsRed2 protein expression during the early stage of bovine somatic cell nuclear transfer embryo development. In Vitro Cell Dev Biol Anim 2016; 52:812-22. [PMID: 27287919 DOI: 10.1007/s11626-016-0053-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 05/02/2016] [Indexed: 01/20/2023]
Abstract
Somatic cell nuclear transfer (SCNT) has been widely used as an efficient tool in biomedical research for the generation of transgenic animals from somatic cells with genetic modifications. Although remarkable advances in SCNT techniques have been reported in a variety of mammals, the cloning efficiency in domestic animals is still low due to the developmental defects of SCNT embryos. In particular, recent evidence has revealed that mitochondrial dysfunction is detected during the early development of SCNT embryos. However, there have been relatively few or no studies regarding the development of a system for evaluating mitochondrial behavior or dynamics. For the first time, in mitochondria of bovine SCNT embryos, we developed a method for the visualization of mitochondria and expression of fluorescence proteins. To express red fluorescence in mitochondria of cloned embryos, bovine ear skin fibroblasts, nuclear donor, were stably transfected with a vector carrying mitochondria-targeting DsRed2 gene tagged with V5 epitope (mito-DsRed2-V5 tag) using lentivirus-mediated gene transfer because of its ability to integrate in the cell genome and the potential for long-term transgene expression in the transduced cells and their dividing cells. From western blotting analysis of V5 tag protein using mitochondrial fraction and confocal microscopy of red fluorescence using SCNT embryos, we found that the mitochondrial expression of the mito-DsRed2 protein was detected until the blastocyst stage. In addition, according to image analysis, it may be suggested possible use of the system for visualization of mitochondrial localization and evaluation of mitochondrial behaviors or dynamics in early development of bovine SCNT embryos.
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Affiliation(s)
- Hyo-Jin Park
- School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Sung-Hun Min
- Center of Reproductive Medicine, Good Moonhwa Hospital, Busan, 48735, Republic of Korea
- Department of Biotechnology, Daegu University, Gyeongsan, 38453, Republic of Korea
| | - Hoonsung Choi
- School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Republic of Korea
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju, 55365, Korea
| | - Junghyung Park
- School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Sun-Uk Kim
- National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Seunghoon Lee
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Wanju, 55365, Korea
| | - Sang-Rae Lee
- National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Il-Keun Kong
- Department of Animal Science, Division of Applied Life Science (BK21 Plus), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Kyu-Tae Chang
- National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Deog-Bon Koo
- Department of Biotechnology, Daegu University, Gyeongsan, 38453, Republic of Korea.
| | - Dong-Seok Lee
- School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Republic of Korea.
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43
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Johnston IG, Williams BP. Evolutionary Inference across Eukaryotes Identifies Specific Pressures Favoring Mitochondrial Gene Retention. Cell Syst 2016; 2:101-11. [PMID: 27135164 DOI: 10.1016/j.cels.2016.01.013] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 12/14/2015] [Accepted: 01/27/2016] [Indexed: 11/18/2022]
Abstract
Since their endosymbiotic origin, mitochondria have lost most of their genes. Although many selective mechanisms underlying the evolution of mitochondrial genomes have been proposed, a data-driven exploration of these hypotheses is lacking, and a quantitatively supported consensus remains absent. We developed HyperTraPS, a methodology coupling stochastic modeling with Bayesian inference, to identify the ordering of evolutionary events and suggest their causes. Using 2015 complete mitochondrial genomes, we inferred evolutionary trajectories of mtDNA gene loss across the eukaryotic tree of life. We find that proteins comprising the structural cores of the electron transport chain are preferentially encoded within mitochondrial genomes across eukaryotes. A combination of high GC content and high protein hydrophobicity is required to explain patterns of mtDNA gene retention; a model that accounts for these selective pressures can also predict the success of artificial gene transfer experiments in vivo. This work provides a general method for data-driven inference of the ordering of evolutionary and progressive events, here identifying the distinct features shaping mitochondrial genomes of present-day species.
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Affiliation(s)
- Iain G Johnston
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK.
| | - Ben P Williams
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
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44
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Balobaid A, Qari A, Al-Zaidan H. Genetic counselors' scope of practice and challenges in genetic counseling services in Saudi Arabia. Int J Pediatr Adolesc Med 2016; 3:1-6. [PMID: 30805460 PMCID: PMC6372413 DOI: 10.1016/j.ijpam.2015.12.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 12/17/2015] [Indexed: 12/18/2022]
Abstract
Genetic counseling is an evolving field in Saudi Arabia. In 2015, genetic counseling was recognized as a Master's program by the Saudi Commission for Health Specialties. Our genetic counselors combine their knowledge of genetics, counseling theory and interpersonal communication to serve Saudi and non-Saudi patients affected with a range of genetic conditions and/or birth defects. Most patients are referred to the clinic from different clinics at King Faisal Specialist Hospital and Research Centre (KFSHRC) and outside of KFSHRC for various indications. Carrier testing and preventative reproduction options rank highly on the reasons for referral to our clinics. The Saudi population has unique customs and beliefs, such as consanguinity and the evil eye. Challenges that are routinely encountered in our genetic counseling clinics include, but are not limited to, preventative reproductive options and termination of pregnancy, manifesting carriers, stigmatization of women and approaches to complex molecular findings. Working with families from different backgrounds and beliefs undoubtedly requires professionals with a distinctive set of skills and a structured clinical setting. This review article presents the scope of genetic counseling practice and tackles some of the challenges faced in providing genetic counseling in Saudi Arabia.
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Affiliation(s)
- Ameera Balobaid
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Alya Qari
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Hamad Al-Zaidan
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
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45
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Muir R, Diot A, Poulton J. Mitochondrial content is central to nuclear gene expression: Profound implications for human health. Bioessays 2016; 38:150-6. [PMID: 26725055 PMCID: PMC4819685 DOI: 10.1002/bies.201500105] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We review a recent paper in Genome Research by Guantes et al. showing that nuclear gene expression is influenced by the bioenergetic status of the mitochondria. The amount of energy that mitochondria make available for gene expression varies considerably. It depends on: the energetic demands of the tissue; the mitochondrial DNA (mtDNA) mutant load; the number of mitochondria; stressors present in the cell. Hence, when failing mitochondria place the cell in energy crisis there are major effects on gene expression affecting the risk of degenerative diseases, cancer and ageing. In 2015 the UK parliament approved a change in the regulation of IVF techniques, allowing "Mitochondrial replacement therapy" to become a reproductive choice for women at risk of transmitting mitochondrial disease to their children. This is the first time that this technique will be available. Therefore understanding the interaction between mitochondria and the nucleus has never been more important.
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Affiliation(s)
- Rebecca Muir
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Alan Diot
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Joanna Poulton
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, John Radcliffe Hospital, Oxford, UK
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46
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Johnston IG, Burgstaller JP, Havlicek V, Kolbe T, Rülicke T, Brem G, Poulton J, Jones NS. Stochastic modelling, Bayesian inference, and new in vivo measurements elucidate the debated mtDNA bottleneck mechanism. eLife 2015; 4:e07464. [PMID: 26035426 PMCID: PMC4486817 DOI: 10.7554/elife.07464] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 05/29/2015] [Indexed: 12/14/2022] Open
Abstract
Dangerous damage to mitochondrial DNA (mtDNA) can be ameliorated during mammalian development through a highly debated mechanism called the mtDNA bottleneck. Uncertainty surrounding this process limits our ability to address inherited mtDNA diseases. We produce a new, physically motivated, generalisable theoretical model for mtDNA populations during development, allowing the first statistical comparison of proposed bottleneck mechanisms. Using approximate Bayesian computation and mouse data, we find most statistical support for a combination of binomial partitioning of mtDNAs at cell divisions and random mtDNA turnover, meaning that the debated exact magnitude of mtDNA copy number depletion is flexible. New experimental measurements from a wild-derived mtDNA pairing in mice confirm the theoretical predictions of this model. We analytically solve a mathematical description of this mechanism, computing probabilities of mtDNA disease onset, efficacy of clinical sampling strategies, and effects of potential dynamic interventions, thus developing a quantitative and experimentally-supported stochastic theory of the bottleneck. DOI:http://dx.doi.org/10.7554/eLife.07464.001 Mitochondria are structures that provide vital sources of energy in our cells. DNA contained within mitochondria encodes important mitochondrial machinery, and most human cells contain hundreds or thousands of mitochondrial DNA molecules in addition to the DNA that is stored in the nucleus. Mitochondrial DNA is inherited from mothers via the egg, and the details of this inheritance are poorly understood. This question is important because inherited mistakes in mitochondrial DNA can have detrimental consequences on health, with links to fatal diseases and many other conditions. An unfertilised egg cell contains many copies of mitochondrial DNA molecules; some may have mutations and some may not. After fertilisation, the egg divides, the number of cells in the developing embryo increases, and the number of mitochondrial DNA molecules per cell changes. If the original egg cell contained defective mitochondrial DNA, some of these new cells end up containing more defective copies than others, leading to cell-to-cell differences in the developing embryo. This potentially allows cells with the greatest number of defective mitochondria to be eliminated. The increase in this cell-to-cell variability is called ‘bottlenecking’, and its mechanism remains highly debated. Johnston et al. have now used tools from maths, statistics and new experiments to address this debate, in the light of several studies that measured the mitochondrial DNA content in developing mice. This approach allowed a new theoretical model of mitochondrial DNA during the growth of an organism to be produced, which encompasses a wide range of existing theories and allows them to be compared. This model starts from the viewpoint that the hundreds or thousands of mitochondrial DNA molecules in a cell can be thought of as a population undergoing random ‘birth’ and ‘death’, and it allows the first statistical comparison of the many proposed bottleneck mechanisms. Johnston et al. find support for two ways that cells segregate mitochondria as they multiply, and show that the decrease in the number of mitochondrial DNA molecules during bottlenecking is flexible. This reconciles a debate amongst previous studies. These findings are confirmed using new experimental data from mice, which are genetically distinct from existing studies, illustrating the generality of the model's findings. Furthermore, an analytic mathematical description that describes in detail how bottlenecking might work is produced. Finally, Johnston et al. provide examples using this new theoretical model to suggest therapeutic strategies for diseases caused by mitochondrial DNA mutations. Future work will need to test these suggestions, and link mathematical understanding of mitochondria with healthcare data. DOI:http://dx.doi.org/10.7554/eLife.07464.002
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Affiliation(s)
- Iain G Johnston
- Department of Mathematics, Imperial College London, London, United Kingdom
| | - Joerg P Burgstaller
- Biotechnology in Animal Production, Department for Agrobiotechnology, IFA Tulln, IFA Tulln, Tulln, Austria
| | - Vitezslav Havlicek
- Reproduction Centre Wieselburg, Department for Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Thomas Kolbe
- Biomodels Austria, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Thomas Rülicke
- Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Gottfried Brem
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Jo Poulton
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Oxford, United Kingdom
| | - Nick S Jones
- Department of Mathematics, Imperial College London, London, United Kingdom
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