51
|
Aw WC, Towarnicki SG, Melvin RG, Youngson NA, Garvin MR, Hu Y, Nielsen S, Thomas T, Pickford R, Bustamante S, Vila-Sanjurjo A, Smyth GK, Ballard JWO. Genotype to phenotype: Diet-by-mitochondrial DNA haplotype interactions drive metabolic flexibility and organismal fitness. PLoS Genet 2018; 14:e1007735. [PMID: 30399141 PMCID: PMC6219761 DOI: 10.1371/journal.pgen.1007735] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 10/02/2018] [Indexed: 02/07/2023] Open
Abstract
Diet may be modified seasonally or by biogeographic, demographic or cultural shifts. It can differentially influence mitochondrial bioenergetics, retrograde signalling to the nuclear genome, and anterograde signalling to mitochondria. All these interactions have the potential to alter the frequencies of mtDNA haplotypes (mitotypes) in nature and may impact human health. In a model laboratory system, we fed four diets varying in Protein: Carbohydrate (P:C) ratio (1:2, 1:4, 1:8 and 1:16 P:C) to four homoplasmic Drosophila melanogaster mitotypes (nuclear genome standardised) and assayed their frequency in population cages. When fed a high protein 1:2 P:C diet, the frequency of flies harbouring Alstonville mtDNA increased. In contrast, when fed the high carbohydrate 1:16 P:C food the incidence of flies harbouring Dahomey mtDNA increased. This result, driven by differences in larval development, was generalisable to the replacement of the laboratory diet with fruits having high and low P:C ratios, perturbation of the nuclear genome and changes to the microbiome. Structural modelling and cellular assays suggested a V161L mutation in the ND4 subunit of complex I of Dahomey mtDNA was mildly deleterious, reduced mitochondrial functions, increased oxidative stress and resulted in an increase in larval development time on the 1:2 P:C diet. The 1:16 P:C diet triggered a cascade of changes in both mitotypes. In Dahomey larvae, increased feeding fuelled increased β-oxidation and the partial bypass of the complex I mutation. Conversely, Alstonville larvae upregulated genes involved with oxidative phosphorylation, increased glycogen metabolism and they were more physically active. We hypothesise that the increased physical activity diverted energy from growth and cell division and thereby slowed development. These data further question the use of mtDNA as an assumed neutral marker in evolutionary and population genetic studies. Moreover, if humans respond similarly, we posit that individuals with specific mtDNA variations may differentially metabolise carbohydrates, which has implications for a variety of diseases including cardiovascular disease, obesity, and perhaps Parkinson's Disease.
Collapse
Affiliation(s)
- Wen C. Aw
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Samuel G. Towarnicki
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Richard G. Melvin
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Neil A. Youngson
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Michael R. Garvin
- School of Biological Sciences, Washington State University, Pullman, Washington, United States of America
| | - Yifang Hu
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
| | - Shaun Nielsen
- Centre for Marine Bio-Innovation and School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Torsten Thomas
- Centre for Marine Bio-Innovation and School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Russell Pickford
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Center, The University of New South Wales, Sydney, NSW, Australia
| | - Sonia Bustamante
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Center, The University of New South Wales, Sydney, NSW, Australia
| | - Antón Vila-Sanjurjo
- Grupo GIBE, Bioloxía Celular e Molecular, Facultade de Ciencias, Universidade da Coruña (UDC), Campus Zapateira s/n, A Coruña, Spain
| | - Gordon K. Smyth
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
- School of Mathematics and Statistics, The University of Melbourne, Melbourne, Victoria, Australia
| | - J. William O. Ballard
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
52
|
Vaught RC, Dowling DK. Maternal inheritance of mitochondria: implications for male fertility? Reproduction 2018; 155:R159-R168. [PMID: 29581388 DOI: 10.1530/rep-17-0600] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 01/18/2018] [Indexed: 12/16/2022]
Abstract
Evolutionary theory predicts maternal inheritance of the mitochondria will lead to the accumulation of mutations in the mitochondrial DNA (mtDNA) that impair male fertility, but leave females unaffected. The hypothesis has been referred to as 'Mother's Curse'. There are many examples of mtDNA mutations or haplotypes, in humans and other metazoans, associated with decreases in sperm performance, but seemingly few reports of associations involving female reproductive traits; an observation that has been used to support the Mother's Curse hypothesis. However, it is unclear whether apparent signatures of male bias in mitochondrial genetic effects on fertility reflect an underlying biological bias or a technical bias resulting from a lack of studies to have screened for female effects. Here, we conduct a systematic literature search of studies reporting mitochondrial genetic effects on fertility-related traits in gonochoristic metazoans (animals with two distinct sexes). Studies of female reproductive outcomes were sparse, reflecting a large technical sex bias across the literature. We were only able to make a valid assessment of sex specificity of mitochondrial genetic effects in 30% of cases. However, in most of these cases, the effects were male biased, including examples of male bias associated with mtDNA mutations in humans. These results are therefore consistent with the hypothesis that maternal inheritance has enriched mtDNA sequences with mutations that specifically impair male fertility. However, future research that redresses the technical imbalance in studies conducted per sex will be key to enabling researchers to fully assess the wider implications of the Mother's Curse hypothesis to male reproductive biology.
Collapse
Affiliation(s)
- R C Vaught
- School of Biological SciencesMonash University, Clayton, Victoria, Australia
| | - D K Dowling
- School of Biological SciencesMonash University, Clayton, Victoria, Australia
| |
Collapse
|
53
|
Abstract
Mutations of mtDNA accumulate in aging humans and other mammals to cause mitochondrial dysfunction in a subset of cells in various tissues. Furthermore, experimental induction of mtDNA mutations causes a premature aging syndrome in the mouse. To study if mitochondrial dysfunction is universally involved in shortening life span in metazoans, we generated a series of fruit fly lines with varying levels of mtDNA mutations. Unexpectedly, we report that fruit flies are remarkably tolerant to mtDNA mutations, as exemplified by their lack of effect on physiology and lifespan. Only an artificially induced, very drastic increase of the mtDNA mutation load will lead to reduced lifespan, showing that mtDNA mutations are unlikely to limit lifespan in natural fruit fly populations. Mammals develop age-associated clonal expansion of somatic mtDNA mutations resulting in severe respiratory chain deficiency in a subset of cells in a variety of tissues. Both mathematical modeling based on descriptive data from humans and experimental data from mtDNA mutator mice suggest that the somatic mutations are formed early in life and then undergo mitotic segregation during adult life to reach very high levels in certain cells. To address whether mtDNA mutations have a universal effect on aging metazoans, we investigated their role in physiology and aging of fruit flies. To this end, we utilized genetically engineered flies expressing mutant versions of the catalytic subunit of mitochondrial DNA polymerase (DmPOLγA) as a means to introduce mtDNA mutations. We report here that lifespan and health in fruit flies are remarkably tolerant to mtDNA mutations. Our results show that the short lifespan and wide genetic bottleneck of fruit flies are limiting the extent of clonal expansion of mtDNA mutations both in individuals and between generations. However, an increase of mtDNA mutations to very high levels caused sensitivity to mechanical and starvation stress, intestinal stem cell dysfunction, and reduced lifespan under standard conditions. In addition, the effects of dietary restriction, widely considered beneficial for organismal health, were attenuated in flies with very high levels of mtDNA mutations.
Collapse
|
54
|
Experimental evidence that thermal selection shapes mitochondrial genome evolution. Sci Rep 2018; 8:9500. [PMID: 29934612 PMCID: PMC6015072 DOI: 10.1038/s41598-018-27805-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/04/2018] [Indexed: 12/11/2022] Open
Abstract
Mitochondria are essential organelles, found within eukaryotic cells, which contain their own DNA. Mitochondrial DNA (mtDNA) has traditionally been used in population genetic and biogeographic studies as a maternally-inherited and evolutionary-neutral genetic marker. However, it is now clear that polymorphisms within the mtDNA sequence are routinely non-neutral, and furthermore several studies have suggested that such mtDNA polymorphisms are also sensitive to thermal selection. These observations led to the formulation of the “mitochondrial climatic adaptation” hypothesis, for which all published evidence to date is correlational. Here, we use laboratory-based experimental evolution in the fruit fly, Drosophila melanogaster, to test whether thermal selection can shift population frequencies of two mtDNA haplogroups whose natural frequencies exhibit clinal associations with latitude along the Australian east-coast. We present experimental evidence that the thermal regime in which the laboratory populations were maintained drove changes in haplogroup frequencies across generations. Our results strengthen the emerging view that intra-specific mtDNA variants are sensitive to selection, and suggest spatial distributions of mtDNA variants in natural populations of metazoans might reflect adaptation to climatic environments rather than within-population coalescence and diffusion of selectively-neutral haplotypes across populations.
Collapse
|
55
|
Loewen CA, Ganetzky B. Mito-Nuclear Interactions Affecting Lifespan and Neurodegeneration in a Drosophila Model of Leigh Syndrome. Genetics 2018; 208:1535-1552. [PMID: 29496745 PMCID: PMC5887147 DOI: 10.1534/genetics.118.300818] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 02/19/2018] [Indexed: 12/18/2022] Open
Abstract
Proper mitochondrial activity depends upon proteins encoded by genes in the nuclear and mitochondrial genomes that must interact functionally and physically in a precisely coordinated manner. Consequently, mito-nuclear allelic interactions are thought to be of crucial importance on an evolutionary scale, as well as for manifestation of essential biological phenotypes, including those directly relevant to human disease. Nonetheless, detailed molecular understanding of mito-nuclear interactions is still lacking, and definitive examples of such interactions in vivo are sparse. Here we describe the characterization of a mutation in Drosophila ND23, a nuclear gene encoding a highly conserved subunit of mitochondrial complex 1. This characterization led to the discovery of a mito-nuclear interaction that affects the ND23 mutant phenotype. ND23 mutants exhibit reduced lifespan, neurodegeneration, abnormal mitochondrial morphology, and decreased ATP levels. These phenotypes are similar to those observed in patients with Leigh syndrome, which is caused by mutations in a number of nuclear genes that encode mitochondrial proteins, including the human ortholog of ND23 A key feature of Leigh syndrome, and other mitochondrial disorders, is unexpected and unexplained phenotypic variability. We discovered that the phenotypic severity of ND23 mutations varies depending on the maternally inherited mitochondrial background. Sequence analysis of the relevant mitochondrial genomes identified several variants that are likely candidates for the phenotypic interaction with mutant ND23, including a variant affecting a mitochondrially encoded component of complex I. Thus, our work provides an in vivo demonstration of the phenotypic importance of mito-nuclear interactions in the context of mitochondrial disease.
Collapse
Affiliation(s)
- Carin A Loewen
- Laboratory of Genetics, University of Wisconsin-Madison, Wisconsin 53706-1580
| | - Barry Ganetzky
- Laboratory of Genetics, University of Wisconsin-Madison, Wisconsin 53706-1580
| |
Collapse
|
56
|
Lin CC, Kurashige M, Liu Y, Terabayashi T, Ishimoto Y, Wang T, Choudhary V, Hobbs R, Liu LK, Lee PH, Outeda P, Zhou F, Restifo NP, Watnick T, Kawano H, Horie S, Prinz W, Xu H, Menezes LF, Germino GG. A cleavage product of Polycystin-1 is a mitochondrial matrix protein that affects mitochondria morphology and function when heterologously expressed. Sci Rep 2018; 8:2743. [PMID: 29426897 PMCID: PMC5807443 DOI: 10.1038/s41598-018-20856-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 01/22/2018] [Indexed: 12/18/2022] Open
Abstract
Recent studies have reported intrinsic metabolic reprogramming in Pkd1 knock-out cells, implicating dysregulated cellular metabolism in the pathogenesis of polycystic kidney disease. However, the exact nature of the metabolic changes and their underlying cause remains controversial. We show herein that Pkd1 k o /ko renal epithelial cells have impaired fatty acid utilization, abnormal mitochondrial morphology and function, and that mitochondria in kidneys of ADPKD patients have morphological alterations. We further show that a C-terminal cleavage product of polycystin-1 (CTT) translocates to the mitochondria matrix and that expression of CTT in Pkd1 ko/ko cells rescues some of the mitochondrial phenotypes. Using Drosophila to model in vivo effects, we find that transgenic expression of mouse CTT results in decreased viability and exercise endurance but increased CO2 production, consistent with altered mitochondrial function. Our results suggest that PC1 may play a direct role in regulating mitochondrial function and cellular metabolism and provide a framework to understand how impaired mitochondrial function could be linked to the regulation of tubular diameter in both physiological and pathological conditions.
Collapse
Affiliation(s)
- Cheng-Chao Lin
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Mahiro Kurashige
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Yi Liu
- Laboratory of Molecular Genetics; National Heart, Lung and Blood Institute, NIH, Bethesda, MD, USA
| | - Takeshi Terabayashi
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Yu Ishimoto
- Division of Nephrology and Endocrinology and the Division of CKD Pathophysiology, University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Tanchun Wang
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Vineet Choudhary
- Laboratory of Cell and Molecular Biology; National Institute of Diabetes and Digestive and Kidney Disease, NIH, Bethesda, MD, USA
| | - Ryan Hobbs
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Li-Ka Liu
- Laboratory of Cell and Molecular Biology; National Institute of Diabetes and Digestive and Kidney Disease, NIH, Bethesda, MD, USA
| | - Ping-Hsien Lee
- Center for Cell-Based Therapy, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Patricia Outeda
- Department of Medicine, Division of Nephrology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Fang Zhou
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Nicholas P Restifo
- Center for Cell-Based Therapy, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Terry Watnick
- Department of Medicine, Division of Nephrology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Haruna Kawano
- Department of Urology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Shigeo Horie
- Department of Urology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - William Prinz
- Laboratory of Cell and Molecular Biology; National Institute of Diabetes and Digestive and Kidney Disease, NIH, Bethesda, MD, USA
| | - Hong Xu
- Laboratory of Molecular Genetics; National Heart, Lung and Blood Institute, NIH, Bethesda, MD, USA
| | - Luis F Menezes
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA.
| | - Gregory G Germino
- Kidney Disease Branch; National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health (NIH), Bethesda, MD, USA.
| |
Collapse
|
57
|
Ren Q, Zhang F, Xu H. Proliferation Cycle Causes Age Dependent Mitochondrial Deficiencies and Contributes to the Aging of Stem Cells. Genes (Basel) 2017; 8:genes8120397. [PMID: 29257059 PMCID: PMC5748715 DOI: 10.3390/genes8120397] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 11/17/2017] [Accepted: 12/14/2017] [Indexed: 12/15/2022] Open
Abstract
In addition to chronological aging, stem cells are also subject to proliferative aging during the adult life span. However, the consequences of proliferative cycle and their contributions to stem cells aging have not been well investigated. Using Drosophila female germ line stem cells as a model, we found that the replication cycle leads to the age dependent decline of female fecundity, and is a major factor causing developmental abnormalities in the progeny of old females. The proliferative aging does not cause telomere shortening, but causes an accumulation of mitochondrial DNA (mtDNA) mutations or rearrangements at the control region. We propose that damaging mutations on mtDNA caused by accumulation of proliferation cycles in aged stem cells may disrupt mitochondrial respiration chain and impair mtDNA replication and represent a conserved mechanism underlying stem cell aging.
Collapse
Affiliation(s)
- Qiuting Ren
- Laboratory of Molecular Genetics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Fan Zhang
- Laboratory of Molecular Genetics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Hong Xu
- Laboratory of Molecular Genetics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
58
|
Wada KI, Hosokawa K, Ito Y, Maeda M. Quantitative control of mitochondria transfer between live single cells using a microfluidic device. Biol Open 2017; 6:1960-1965. [PMID: 29092814 PMCID: PMC5769642 DOI: 10.1242/bio.024869] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Quantitative control of mitochondria transfer between live cells is a promising approach for genetic manipulation of mitochondrial DNA (mtDNA) because single mitochondrion transfer to a mtDNA-less (ρ0) cell potentially leads to homoplasmy of mtDNA. In this paper, we describe a method for quantitative control of mitochondria transfer between live single cells. For this purpose, we fabricated novel microfluidic devices having cell paring structures with a 4.1, 5.6 or 10.0 μm-length microtunnel. When cells were fused through a microtunnel using the Sendai virus envelope-based method, a strictured cytoplasmic connection was achieved with a length corresponding to that of the microtunnel. Elongation of the cytoplasmic connection led to a decrease in mitochondria transfer to the fusion partner. Moreover, some cell pairs that fused through a 10.0 μm-length microtunnel showed single mitochondrion transfer. Fused cells were spontaneously disconnected from each other when they were recovered in a normal culture medium. These results suggest that our cell fusion method can perform quantitative control of mitochondria transfer that includes a single mitochondrion transfer. Summary: We developed a novel mitochondria transfer platform using a microfluidic device, and succeeded in single mitochondrion transfer between live single cells.
Collapse
Affiliation(s)
- Ken-Ichi Wada
- Bioengineering Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kazuo Hosokawa
- Bioengineering Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yoshihiro Ito
- Nano Medical Engineering Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mizuo Maeda
- Bioengineering Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| |
Collapse
|
59
|
Sen A, Cox RT. Fly Models of Human Diseases: Drosophila as a Model for Understanding Human Mitochondrial Mutations and Disease. Curr Top Dev Biol 2016; 121:1-27. [PMID: 28057297 DOI: 10.1016/bs.ctdb.2016.07.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mitochondrial diseases are a prevalent, heterogeneous class of diseases caused by defects in oxidative phosphorylation, whose severity depends upon particular genetic mutations. These diseases can be difficult to diagnose, and current therapeutics have limited efficacy, primarily treating only symptoms. Because mitochondria play a pivotal role in numerous cellular functions, especially ATP production, their diminished activity has dramatic physiological consequences. While this in and of itself makes treating mitochondrial disease complex, these organelles contain their own DNA, mtDNA, whose products are required for ATP production, in addition to the hundreds of nucleus-encoded proteins. Drosophila offers a tractable whole-animal model to understand the mechanisms underlying loss of mitochondrial function, the subsequent cellular and tissue damage that results, and how these organelles are inherited. Human and Drosophila mtDNAs encode the same set of products, and the homologous nucleus-encoded genes required for mitochondrial function are conserved. In addition, Drosophila contain sufficiently complex organ systems to effectively recapitulate many basic symptoms of mitochondrial diseases, yet are relatively easy and fast to genetically manipulate. There are several Drosophila models for specific mitochondrial diseases, which have been recently reviewed (Foriel, Willems, Smeitink, Schenck, & Beyrath, 2015). In this review, we highlight the conservation between human and Drosophila mtDNA, the present and future techniques for creating mtDNA mutations for further study, and how Drosophila has contributed to our current understanding of mitochondrial inheritance.
Collapse
Affiliation(s)
- A Sen
- Uniformed Services University, Bethesda, MD, United States
| | - R T Cox
- Uniformed Services University, Bethesda, MD, United States.
| |
Collapse
|
60
|
Patel MR, Miriyala GK, Littleton AJ, Yang H, Trinh K, Young JM, Kennedy SR, Yamashita YM, Pallanck LJ, Malik HS. A mitochondrial DNA hypomorph of cytochrome oxidase specifically impairs male fertility in Drosophila melanogaster. eLife 2016; 5:e16923. [PMID: 27481326 PMCID: PMC4970871 DOI: 10.7554/elife.16923] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 06/30/2016] [Indexed: 12/17/2022] Open
Abstract
Due to their strict maternal inheritance in most animals and plants, mitochondrial genomes are predicted to accumulate mutations that are beneficial or neutral in females but harmful in males. Although a few male-harming mtDNA mutations have been identified, consistent with this 'Mother's Curse', their effect on females has been largely unexplored. Here, we identify COII(G177S), a mtDNA hypomorph of cytochrome oxidase II, which specifically impairs male fertility due to defects in sperm development and function without impairing other male or female functions. COII(G177S) represents one of the clearest examples of a 'male-harming' mtDNA mutation in animals and suggest that the hypomorphic mtDNA mutations like COII(G177S) might specifically impair male gametogenesis. Intriguingly, some D. melanogaster nuclear genetic backgrounds can fully rescue COII(G177S) -associated sterility, consistent with previously proposed models that nuclear genomes can regulate the phenotypic manifestation of mtDNA mutations.
Collapse
Affiliation(s)
- Maulik R Patel
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
- Howard Hughes Medical Institute, Seattle, United States
- Department of Biological Sciences, Vanderbilt University, Nashville, United States
| | - Ganesh K Miriyala
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Aimee J Littleton
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Heiko Yang
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, United States
| | - Kien Trinh
- Genome Sciences, University of Washington, Seattle, United States
| | - Janet M Young
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Scott R Kennedy
- Pathology, University of Washington Medical Center, Seattle, United States
| | - Yukiko M Yamashita
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, United States
| | - Leo J Pallanck
- Genome Sciences, University of Washington, Seattle, United States
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
- Howard Hughes Medical Institute, Seattle, United States
| |
Collapse
|
61
|
Wisnovsky S, Lei E, Jean S, Kelley S. Mitochondrial Chemical Biology: New Probes Elucidate the Secrets of the Powerhouse of the Cell. Cell Chem Biol 2016; 23:917-27. [DOI: 10.1016/j.chembiol.2016.06.012] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/02/2016] [Accepted: 06/20/2016] [Indexed: 12/25/2022]
|
62
|
Zhang Y, Chen Y, Gucek M, Xu H. The mitochondrial outer membrane protein MDI promotes local protein synthesis and mtDNA replication. EMBO J 2016; 35:1045-57. [PMID: 27053724 DOI: 10.15252/embj.201592994] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 03/01/2016] [Indexed: 12/21/2022] Open
Abstract
Early embryonic development features rapid nuclear DNA replication cycles, but lacks mtDNA replication. To meet the high-energy demands of embryogenesis, mature oocytes are furnished with vast amounts of mitochondria and mtDNA However, the cellular machinery driving massive mtDNA replication in ovaries remains unknown. Here, we describe a Drosophila AKAP protein, MDI that recruits a translation stimulator, La-related protein (Larp), to the mitochondrial outer membrane in ovaries. The MDI-Larp complex promotes the synthesis of a subset of nuclear-encoded mitochondrial proteins by cytosolic ribosomes on the mitochondrial surface. MDI-Larp's targets include mtDNA replication factors, mitochondrial ribosomal proteins, and electron-transport chain subunits. Lack of MDI abolishes mtDNA replication in ovaries, which leads to mtDNA deficiency in mature eggs. Targeting Larp to the mitochondrial outer membrane independently of MDI restores local protein synthesis and rescues the phenotypes of mdi mutant flies. Our work suggests that a selective translational boost by the MDI-Larp complex on the outer mitochondrial membrane might be essential for mtDNA replication and mitochondrial biogenesis during oogenesis.
Collapse
Affiliation(s)
- Yi Zhang
- Laboratory of Molecular Genetics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Yong Chen
- Proteomics Core, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Marjan Gucek
- Proteomics Core, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Hong Xu
- Laboratory of Molecular Genetics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
63
|
Review: can diet influence the selective advantage of mitochondrial DNA haplotypes? Biosci Rep 2015; 35:BSR20150232. [PMID: 26543031 PMCID: PMC4708006 DOI: 10.1042/bsr20150232] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/05/2015] [Indexed: 01/12/2023] Open
Abstract
This review explores the potential for changes in dietary macronutrients to differentially influence mitochondrial bioenergetics and thereby the frequency of mtDNA haplotypes in natural populations. Such dietary modification may be seasonal or result from biogeographic or demographic shifts. Mechanistically, mtDNA haplotypes may influence the activity of the electron transport system (ETS), retrograde signalling to the nuclear genome and affect epigenetic modifications. Thus, differential provisioning by macronutrients may lead to selection through changes in the levels of ATP production, modulation of metabolites (including AMP, reactive oxygen species (ROS) and the NAD+/NADH ratio) and potentially complex epigenetic effects. The exquisite complexity of dietary influence on haplotype frequency is further illustrated by the fact that macronutrients may differentially influence the selective advantage of specific mutations in different life-history stages. In Drosophila, complex I mutations may affect larval growth because dietary nutrients are fed through this complex in immaturity. In contrast, the majority of electrons are provided to complex III in adult flies. We conclude the review with a case study that considers specific interactions between diet and complex I of the ETS. Complex I is the first enzyme of the mitochondrial ETS and co-ordinates in the oxidation of NADH and transfer of electrons to ubiquinone. Although the supposition that mtDNA variants may be selected upon by dietary macronutrients could be intuitively consistent to some and counter intuitive to others, it must face a multitude of scientific hurdles before it can be recognized.
Collapse
|
64
|
Abstract
Mitochondria are key regulators of cellular homeostasis, and mitochondrial dysfunction is strongly linked to neurodegenerative diseases, including Alzheimer's and Parkinson's. Mitochondria communicate their bioenergetic status to the cell via mitochondrial retrograde signaling. To investigate the role of mitochondrial retrograde signaling in neurons, we induced mitochondrial dysfunction in the Drosophila nervous system. Neuronal mitochondrial dysfunction causes reduced viability, defects in neuronal function, decreased redox potential, and reduced numbers of presynaptic mitochondria and active zones. We find that neuronal mitochondrial dysfunction stimulates a retrograde signaling response that controls the expression of several hundred nuclear genes. We show that the Drosophila hypoxia inducible factor alpha (HIFα) ortholog Similar (Sima) regulates the expression of several of these retrograde genes, suggesting that Sima mediates mitochondrial retrograde signaling. Remarkably, knockdown of Sima restores neuronal function without affecting the primary mitochondrial defect, demonstrating that mitochondrial retrograde signaling is partly responsible for neuronal dysfunction. Sima knockdown also restores function in a Drosophila model of the mitochondrial disease Leigh syndrome and in a Drosophila model of familial Parkinson's disease. Thus, mitochondrial retrograde signaling regulates neuronal activity and can be manipulated to enhance neuronal function, despite mitochondrial impairment.
Collapse
|
65
|
Venken KJT, Sarrion-Perdigones A, Vandeventer PJ, Abel NS, Christiansen AE, Hoffman KL. Genome engineering: Drosophila melanogaster and beyond. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 5:233-67. [PMID: 26447401 DOI: 10.1002/wdev.214] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 08/03/2015] [Accepted: 08/20/2015] [Indexed: 12/26/2022]
Abstract
A central challenge in investigating biological phenomena is the development of techniques to modify genomic DNA with nucleotide precision that can be transmitted through the germ line. Recent years have brought a boon in these technologies, now collectively known as genome engineering. Defined genomic manipulations at the nucleotide level enable a variety of reverse engineering paradigms, providing new opportunities to interrogate diverse biological functions. These genetic modifications include controlled removal, insertion, and substitution of genetic fragments, both small and large. Small fragments up to a few kilobases (e.g., single nucleotide mutations, small deletions, or gene tagging at single or multiple gene loci) to large fragments up to megabase resolution can be manipulated at single loci to create deletions, duplications, inversions, or translocations of substantial sections of whole chromosome arms. A specialized substitution of chromosomal portions that presumably are functionally orthologous between different organisms through syntenic replacement, can provide proof of evolutionary conservation between regulatory sequences. Large transgenes containing endogenous or synthetic DNA can be integrated at defined genomic locations, permitting an alternative proof of evolutionary conservation, and sophisticated transgenes can be used to interrogate biological phenomena. Precision engineering can additionally be used to manipulate the genomes of organelles (e.g., mitochondria). Novel genome engineering paradigms are often accelerated in existing, easily genetically tractable model organisms, primarily because these paradigms can be integrated in a rigorous, existing technology foundation. The Drosophila melanogaster fly model is ideal for these types of studies. Due to its small genome size, having just four chromosomes, the vast amount of cutting-edge genetic technologies, and its short life-cycle and inexpensive maintenance requirements, the fly is exceptionally amenable to complex genetic analysis using advanced genome engineering. Thus, highly sophisticated methods developed in the fly model can be used in nearly any sequenced organism. Here, we summarize different ways to perform precise inheritable genome engineering using integrases, recombinases, and DNA nucleases in the D. melanogaster. For further resources related to this article, please visit the WIREs website.
Collapse
Affiliation(s)
- Koen J T Venken
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA.,Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA.,Program in Integrative Molecular and Biomedical Sciences, Baylor College of Medicine, Houston, TX, USA
| | | | - Paul J Vandeventer
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA
| | - Nicholas S Abel
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Audrey E Christiansen
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA
| | - Kristi L Hoffman
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA
| |
Collapse
|
66
|
Ma H, O'Farrell PH. Selections that isolate recombinant mitochondrial genomes in animals. eLife 2015; 4:e07247. [PMID: 26237110 PMCID: PMC4584245 DOI: 10.7554/elife.07247] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 08/01/2015] [Indexed: 12/11/2022] Open
Abstract
Homologous recombination is widespread and catalyzes evolution. Nonetheless, its existence in animal mitochondrial DNA is questioned. We designed selections for recombination between co-resident mitochondrial genomes in various heteroplasmic Drosophila lines. In four experimental settings, recombinant genomes became the sole or dominant genome in the progeny. Thus, selection uncovers occurrence of homologous recombination in Drosophila mtDNA and documents its functional benefit. Double-strand breaks enhanced recombination in the germline and revealed somatic recombination. When the recombination partner was a diverged Drosophila melanogaster genome or a genome from a different species such as Drosophila yakuba, sequencing revealed long continuous stretches of exchange. In addition, the distribution of sequence polymorphisms in recombinants allowed us to map a selected trait to a particular region in the Drosophila mitochondrial genome. Thus, recombination can be harnessed to dissect function and evolution of mitochondrial genome.
Collapse
Affiliation(s)
- Hansong Ma
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
| | - Patrick H O'Farrell
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
| |
Collapse
|
67
|
Chen Z, Qi Y, French S, Zhang G, Covian Garcia R, Balaban R, Xu H. Genetic mosaic analysis of a deleterious mitochondrial DNA mutation in Drosophila reveals novel aspects of mitochondrial regulation and function. Mol Biol Cell 2014; 26:674-84. [PMID: 25501370 PMCID: PMC4325838 DOI: 10.1091/mbc.e14-11-1513] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A lethal mtDNA mutation affecting COX is fully rescued by AOX. The mutant genome level remains constant in the somatic tissues along the aging process in heteroplasmic flies. A genetic scheme creates tissue-specific heteroplasmy in otherwise heteroplasmic background and reveals that Ca2+ mishandling contributes to the neurodegeneration. Various human diseases are associated with mitochondrial DNA (mtDNA) mutations, but heteroplasmy—the coexistence of mutant and wild-type mtDNA—complicates their study. We previously isolated a temperature-lethal mtDNA mutation in Drosophila, mt:CoIT300I, which affects the cytochrome c oxidase subunit I (CoI) locus. In the present study, we found that the decrease in cytochrome c oxidase (COX) activity was ascribable to a temperature-dependent destabilization of cytochrome a heme. Consistently, the viability of homoplasmic flies at 29°C was fully restored by expressing an alternative oxidase, which specifically bypasses the cytochrome chains. Heteroplasmic flies are fully viable and were used to explore the age-related and tissue-specific phenotypes of mt:CoIT300I. The proportion of mt:CoIT300I genome remained constant in somatic tissues along the aging process, suggesting a lack of quality control mechanism to remove defective mitochondria containing a deleterious mtDNA mutation. Using a genetic scheme that expresses a mitochondrially targeted restriction enzyme to induce tissue-specific homoplasmy in heteroplasmic flies, we found that mt:CoIT300I homoplasmy in the eye caused severe neurodegeneration at 29°C. Degeneration was suppressed by improving mitochondrial Ca2+ uptake, suggesting that Ca2+ mishandling contributed to mt:CoIT300I pathogenesis. Our results demonstrate a novel approach for Drosophila mtDNA genetics and its application in modeling mtDNA diseases.
Collapse
Affiliation(s)
- Zhe Chen
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, MD 20892
| | - Yun Qi
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, MD 20892
| | - Stephanie French
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Guofeng Zhang
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892
| | - Raúl Covian Garcia
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Robert Balaban
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Hong Xu
- Laboratory of Molecular Genetics, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|
68
|
Chen Y, Sparks M, Bhandari P, Matkovich SJ, Dorn GW. Mitochondrial genome linearization is a causative factor for cardiomyopathy in mice and Drosophila. Antioxid Redox Signal 2014; 21:1949-59. [PMID: 23909626 PMCID: PMC4208594 DOI: 10.1089/ars.2013.5432] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
AIMS Mitofusin (Mfn)2 redundantly promotes mitochondrial outer membrane tethering and organelle fusion with Mfn1, and uniquely functions as the mitochondrial receptor for Parkin during PTEN-induced putative kinase 1 (PINK1)-Parkin-mediated mitophagy. Selective deletion of Mfn2 with retention of Mfn1 preserves mitochondrial fusion while rendering damaged mitochondria resistant to normal quality control culling mechanisms. Consequently, neuron and cardiomyocyte-specific Mfn2 gene ablation is associated with accumulation of damaged mitochondria and organ dysfunction. Here, we determined how mitochondrial DNA (mtDNA) damage contributes to cardiomyopathy in Mfn2-deficient hearts. RESULTS RNA sequencing of Mfn2-deficient hearts revealed increased expression of some nuclear-encoded mitochondrial genes, but mitochondrial-encoded transcripts were not upregulated in parallel and mtDNA content was decreased. Ultra-deep sequencing of mtDNA showed no increase in single nucleotide mutations, but copy number variations representing insertion-deletion (in-del) mutations were induced over time by cardiomyocyte-specific Mfn2 deficiency. Double-strand mtDNA breaks in the form of in-dels were confirmed by polymerase chain reaction, and in the form of linear mitochondrial genomes were identified by southern blot analysis. Linearization of Drosophila cardiomyocyte mtDNA using conditional cardiomyocyte-specific expression of mitochondrial targeted XhoI recapitulated the cardiomyopathy of Mfn2-deficient mouse hearts. INNOVATION This is the first description of mitochondrial genome linearization as a causative factor in cardiomyopathy. CONCLUSION One of the consequences of interrupting mitochondrial culling by the PINK1-Mfn2-Parkin mechanism is an increase in mtDNA double-stranded breaks, which adversely impact mitochondrial function and DNA replication.
Collapse
Affiliation(s)
- Yun Chen
- Department of Internal Medicine, Center for Pharmacogenomics, Washington University School of Medicine , St. Louis, Missouri
| | | | | | | | | |
Collapse
|
69
|
Burman JL, Itsara LS, Kayser EB, Suthammarak W, Wang AM, Kaeberlein M, Sedensky MM, Morgan PG, Pallanck LJ. A Drosophila model of mitochondrial disease caused by a complex I mutation that uncouples proton pumping from electron transfer. Dis Model Mech 2014; 7:1165-74. [PMID: 25085991 PMCID: PMC4174527 DOI: 10.1242/dmm.015321] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mutations affecting mitochondrial complex I, a multi-subunit assembly that couples electron transfer to proton pumping, are the most frequent cause of heritable mitochondrial diseases. However, the mechanisms by which complex I dysfunction results in disease remain unclear. Here, we describe a Drosophila model of complex I deficiency caused by a homoplasmic mutation in the mitochondrial-DNA-encoded NADH dehydrogenase subunit 2 (ND2) gene. We show that ND2 mutants exhibit phenotypes that resemble symptoms of mitochondrial disease, including shortened lifespan, progressive neurodegeneration, diminished neural mitochondrial membrane potential and lower levels of neural ATP. Our biochemical studies of ND2 mutants reveal that complex I is unable to efficiently couple electron transfer to proton pumping. Thus, our study provides evidence that the ND2 subunit participates directly in the proton pumping mechanism of complex I. Together, our findings support the model that diminished respiratory chain activity, and consequent energy deficiency, are responsible for the pathogenesis of complex-I-associated neurodegeneration.
Collapse
Affiliation(s)
- Jonathon L Burman
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Leslie S Itsara
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA. Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98195, USA
| | - Ernst-Bernhard Kayser
- Center for Developmental Therapeutics, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Wichit Suthammarak
- Center for Developmental Therapeutics, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Adrienne M Wang
- Department of Pathology, University of Washington, Seattle, WA 98195, USA
| | - Matt Kaeberlein
- Department of Pathology, University of Washington, Seattle, WA 98195, USA
| | - Margaret M Sedensky
- Center for Developmental Therapeutics, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Philip G Morgan
- Center for Developmental Therapeutics, Seattle Children's Research Institute, Seattle, WA 98101, USA.
| | - Leo J Pallanck
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
70
|
Towheed A, Markantone DM, Crain AT, Celotto AM, Palladino MJ. Small mitochondrial-targeted RNAs modulate endogenous mitochondrial protein expression in vivo. Neurobiol Dis 2014; 69:15-22. [PMID: 24807207 DOI: 10.1016/j.nbd.2014.04.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 04/04/2014] [Accepted: 04/27/2014] [Indexed: 11/26/2022] Open
Abstract
Endogenous mitochondrial genes encode critical oxidative phosphorylation components and their mutation results in a set of disorders known collectively as mitochondrial encephalomyopathies. There is intensive interest in modulating mitochondrial function as organelle dysfunction has been associated with numerous disease states. Proteins encoded by the mitochondrial genome cannot be genetically manipulated by current techniques. Here we report the development of a mitochondrial-targeted RNA expression system (mtTRES) utilizing distinct non-coding leader sequences (NCLs) and enabling in vivo expression of small mitochondrial-targeted RNAs. mtTRES expressing small chimeric antisense RNAs was used as translational inhibitors (TLIs) to target endogenous mitochondrial protein expression in vivo. By utilizing chimeric antisense RNA we successfully modulate expression of two mitochondrially-encoded proteins, ATP6 and COXII, and demonstrate the utility of this system in vivo and in human cells. This technique has important and obvious research and clinical implications.
Collapse
Affiliation(s)
- Atif Towheed
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Desiree M Markantone
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Aaron T Crain
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Alicia M Celotto
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Michael J Palladino
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
| |
Collapse
|
71
|
Transmission of mitochondrial mutations and action of purifying selection in Drosophila melanogaster. Nat Genet 2014; 46:393-7. [PMID: 24614071 DOI: 10.1038/ng.2919] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/14/2014] [Indexed: 11/08/2022]
Abstract
It is not known how selection affects mutations in the multiple copies of the mitochondrial genome. We transferred cytoplasm between D. melanogaster embryos carrying mitochondrial mutations to create heteroplasmic lines transmitting two mitochondrial genotypes. Increased temperature imposed selection against a temperature-sensitive mutation affecting cytochrome oxidase, driving decreases in the abundance of the mutant genome over successive generations. Selection did not influence the health or fertility of the flies but acted during midoogenesis to influence competition between the genomes. Mitochondria might incur an advantage through selective localization, survival or proliferation, yet timing and insensitivity to park mutation suggest that preferential proliferation underlies selection. Selection drove complete replacement of the temperature-sensitive mitochondrial genome by a wild-type genome but also stabilized the multigenerational transmission of two genomes carrying complementing detrimental mutations. While they are so balanced, these stably transmitted mutations have no detrimental phenotype, but their segregation could contribute to disease phenotypes and somatic aging.
Collapse
|
72
|
Hill JH, Chen Z, Xu H. Selective propagation of functional mitochondrial DNA during oogenesis restricts the transmission of a deleterious mitochondrial variant. Nat Genet 2014; 46:389-92. [PMID: 24614072 PMCID: PMC3976679 DOI: 10.1038/ng.2920] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 02/14/2014] [Indexed: 11/09/2022]
Abstract
Although mitochondrial DNA (mtDNA) is prone to mutation and few mtDNA repair mechanisms exist, crippling mitochondrial mutations are exceedingly rare. Recent studies have demonstrated strong purifying selection in the mouse female germline. However, the mechanisms underlying positive selection of healthy mitochondria remain to be elucidated. We visualized mtDNA replication during Drosophila melanogaster oogenesis, finding that mtDNA replication commenced before oocyte determination during the late germarium stage and was dependent on mitochondrial fitness. We isolated a temperature-sensitive lethal mtDNA allele, mt:CoI(T300I), which resulted in reduced mtDNA replication in the germarium at the restrictive temperature. Additionally, the frequency of the mt:CoI(T300I) allele in heteroplasmic flies was decreased, both during oogenesis and over multiple generations, at the restrictive temperature. Furthermore, we determined that selection against mt:CoI(T300I) overlaps with the timing of selective replication of mtDNA in the germarium. These findings establish a previously uncharacterized developmental mechanism for the selective amplification of wild-type mtDNA, which may be evolutionarily conserved to limit the transmission of deleterious mutations.
Collapse
Affiliation(s)
- Jahda H Hill
- 1] Laboratory of Molecular Genetics, National Heart, Lung, and Blood Institute, US National Institutes of Health, Bethesda, Maryland, USA. [2]
| | - Zhe Chen
- 1] Laboratory of Molecular Genetics, National Heart, Lung, and Blood Institute, US National Institutes of Health, Bethesda, Maryland, USA. [2]
| | - Hong Xu
- Laboratory of Molecular Genetics, National Heart, Lung, and Blood Institute, US National Institutes of Health, Bethesda, Maryland, USA
| |
Collapse
|
73
|
Bacman SR, Williams SL, Pinto M, Moraes CT. The use of mitochondria-targeted endonucleases to manipulate mtDNA. Methods Enzymol 2014; 547:373-97. [PMID: 25416366 DOI: 10.1016/b978-0-12-801415-8.00018-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
For more than a decade, mitochondria-targeted nucleases have been used to promote double-strand breaks in the mitochondrial genome. This was done in mitochondrial DNA (mtDNA) homoplasmic systems, where all mtDNA molecules can be affected, to create models of mitochondrial deficiencies. Alternatively, they were also used in a heteroplasmic model, where only a subset of the mtDNA molecules were substrates for cleavage. The latter approach showed that mitochondrial-targeted nucleases can reduce mtDNA haplotype loads in affected tissues, with clear implications for the treatment of patients with mitochondrial diseases. In the last few years, designer nucleases, such as ZFN and TALEN, have been adapted to cleave mtDNA, greatly expanding the potential therapeutic use. This chapter describes the techniques and approaches used to test these designer enzymes.
Collapse
Affiliation(s)
- Sandra R Bacman
- Department of Neurology, University of Miami School of Medicine, Miami, Florida, USA
| | - Sion L Williams
- Department of Neurology, University of Miami School of Medicine, Miami, Florida, USA
| | - Milena Pinto
- Department of Neurology, University of Miami School of Medicine, Miami, Florida, USA
| | - Carlos T Moraes
- Department of Neurology, University of Miami School of Medicine, Miami, Florida, USA.
| |
Collapse
|
74
|
Affiliation(s)
- J. William O. Ballard
- School of Biotechnology and Biomolecular Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
| | - Nicolas Pichaud
- School of Biotechnology and Biomolecular Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
- Laboratoire de Biologie Intégrative; Département de Biologie, Chimie et Géographie; Université du Québec à Rimouski; Rimouski Quebec Canada
| |
Collapse
|
75
|
Gemmell NJ, Jalilzadeh A, Didham RK, Soboleva T, Tompkins DM. The Trojan female technique: a novel, effective and humane approach for pest population control. Proc Biol Sci 2013; 280:20132549. [PMID: 24174117 DOI: 10.1098/rspb.2013.2549] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour-intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan female technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control.
Collapse
Affiliation(s)
- Neil J Gemmell
- Centre for Reproduction and Genomics and Allan Wilson Centre for Molecular Ecology and Evolution, Department of Anatomy, University of Otago, , Dunedin, New Zealand, Department of Mathematics and Statistics, University of Otago, , Dunedin, New Zealand, School of Animal Biology, University of Western Australia and CSIRO Ecosystem Sciences, , Perth, Western Australia 6009, Australia, Science and Risk Assessment Directorate, Ministry for Primary Industries, , PO Box 2526, Wellington, New Zealand, Landcare Research, , Private Bag 1930, Dunedin, New Zealand
| | | | | | | | | |
Collapse
|
76
|
An Incompatibility between a mitochondrial tRNA and its nuclear-encoded tRNA synthetase compromises development and fitness in Drosophila. PLoS Genet 2013; 9:e1003238. [PMID: 23382693 PMCID: PMC3561102 DOI: 10.1371/journal.pgen.1003238] [Citation(s) in RCA: 180] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 11/27/2012] [Indexed: 11/28/2022] Open
Abstract
Mitochondrial transcription, translation, and respiration require interactions between genes encoded in two distinct genomes, generating the potential for mutations in nuclear and mitochondrial genomes to interact epistatically and cause incompatibilities that decrease fitness. Mitochondrial-nuclear epistasis for fitness has been documented within and between populations and species of diverse taxa, but rarely has the genetic or mechanistic basis of these mitochondrial–nuclear interactions been elucidated, limiting our understanding of which genes harbor variants causing mitochondrial–nuclear disruption and of the pathways and processes that are impacted by mitochondrial–nuclear coevolution. Here we identify an amino acid polymorphism in the Drosophila melanogaster nuclear-encoded mitochondrial tyrosyl–tRNA synthetase that interacts epistatically with a polymorphism in the D. simulans mitochondrial-encoded tRNATyr to significantly delay development, compromise bristle formation, and decrease fecundity. The incompatible genotype specifically decreases the activities of oxidative phosphorylation complexes I, III, and IV that contain mitochondrial-encoded subunits. Combined with the identity of the interacting alleles, this pattern indicates that mitochondrial protein translation is affected by this interaction. Our findings suggest that interactions between mitochondrial tRNAs and their nuclear-encoded tRNA synthetases may be targets of compensatory molecular evolution. Human mitochondrial diseases are often genetically complex and variable in penetrance, and the mitochondrial–nuclear interaction we document provides a plausible mechanism to explain this complexity. The ancient symbiosis between two prokaryotes that gave rise to the eukaryotic cell has required genomic cooperation for at least a billion years. Eukaryotic cells respire through the coordinated expression of their nuclear and mitochondrial genomes, both of which encode the proteins and RNAs required for mitochondrial transcription, translation, and aerobic respiration. Genetic interactions between these genomes are hypothesized to influence the effects of mitochondrial mutations on disease and drive mitochondrial–nuclear coevolution. Here we characterize the molecular cause and the cellular and organismal consequences of a mitochondrial–nuclear interaction in Drosophila between naturally occurring mutations in a mitochondrial tRNA and a nuclear-encoded tRNA synthetase. These mutations have little effect on their own; but, when combined, they severely compromise development and reproduction. tRNA synthetases attach the appropriate amino acid onto their cognate tRNA, and this reaction is required for efficient and accurate protein synthesis. We show that disruption of this interaction compromises mitochondrial function, providing hypotheses for the variable penetrance of diseases associated with mitochondrial tRNAs and for which pathways and processes are likely to be affected by mitochondrial–nuclear interactions.
Collapse
|
77
|
Baile MG, Claypool SM. The power of yeast to model diseases of the powerhouse of the cell. FRONT BIOSCI-LANDMRK 2013; 18:241-78. [PMID: 23276920 PMCID: PMC3874933 DOI: 10.2741/4098] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mitochondria participate in a variety of cellular functions. As such, mitochondrial diseases exhibit numerous clinical phenotypes. Because mitochondrial functions are highly conserved between humans and Saccharomyces cerevisiae, yeast are an excellent model to study mitochondrial disease, providing insight into both physiological and pathophysiological processes.
Collapse
Affiliation(s)
- Matthew G Baile
- Dept. of Physiology, Johns Hopkins School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205-2185, USA
| | | |
Collapse
|
78
|
DeLuca SZ, O'Farrell PH. Barriers to male transmission of mitochondrial DNA in sperm development. Dev Cell 2012; 22:660-8. [PMID: 22421049 DOI: 10.1016/j.devcel.2011.12.021] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 11/09/2011] [Accepted: 12/25/2011] [Indexed: 11/19/2022]
Abstract
Across the eukaryotic phylogeny, offspring usually inherit their mitochondrial genome from only one of two parents: in animals, the female. Although mechanisms that eliminate paternally derived mitochondria from the zygote have been sought, the developmental stage at which paternal transmission of mitochondrial DNA is restricted is unknown in most animals. Here, we show that the mitochondria of mature Drosophila sperm lack DNA, and we uncover two processes that eliminate mitochondrial DNA during spermatogenesis. Visualization of mitochondrial DNA nucleoids revealed their abrupt disappearance from developing spermatids in a process requiring the mitochondrial nuclease, Endonuclease G. In Endonuclease G mutants, persisting nucleoids are swept out of spermatids by a cellular remodeling process that trims and shapes spermatid tails. Our results show that mitochondrial DNA is eliminated during spermatogenesis, thereby removing the capacity of sperm to transmit the mitochondrial genome to the next generation.
Collapse
Affiliation(s)
- Steven Z DeLuca
- Department of Biochemistry, UCSF, San Francisco, CA 94110, USA
| | | |
Collapse
|
79
|
Kalifa L, Quintana DF, Schiraldi LK, Phadnis N, Coles GL, Sia RA, Sia EA. Mitochondrial genome maintenance: roles for nuclear nonhomologous end-joining proteins in Saccharomyces cerevisiae. Genetics 2012; 190:951-64. [PMID: 22214610 PMCID: PMC3296257 DOI: 10.1534/genetics.111.138214] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 12/31/2011] [Indexed: 12/27/2022] Open
Abstract
Mitochondrial DNA (mtDNA) deletions are associated with sporadic and inherited diseases and age-associated neurodegenerative disorders. Approximately 85% of mtDNA deletions identified in humans are flanked by short directly repeated sequences; however, mechanisms by which these deletions arise are unknown. A limitation in deciphering these mechanisms is the essential nature of the mitochondrial genome in most living cells. One exception is budding yeast, which are facultative anaerobes and one of the few organisms for which directed mtDNA manipulation is possible. Using this model system, we have developed a system to simultaneously monitor spontaneous direct-repeat-mediated deletions (DRMDs) in the nuclear and mitochondrial genomes. In addition, the mitochondrial DRMD reporter contains a unique KpnI restriction endonuclease recognition site that is not present in otherwise wild-type (WT) mtDNA. We have expressed KpnI fused to a mitochondrial localization signal to induce a specific mitochondrial double-strand break (mtDSB). Here we report that loss of the MRX (Mre11p, Rad50p, Xrs2p) and Ku70/80 (Ku70p, Ku80p) complexes significantly impacts the rate of spontaneous deletion events in mtDNA, and these proteins contribute to the repair of induced mtDSBs. Furthermore, our data support homologous recombination (HR) as the predominant pathway by which mtDNA deletions arise in yeast, and suggest that the MRX and Ku70/80 complexes are partially redundant in mitochondria.
Collapse
Affiliation(s)
- Lidza Kalifa
- Department of Biology, University of Rochester, Rochester, New York 14627
| | - Daniel F. Quintana
- Department of Biology, University of Rochester, Rochester, New York 14627
| | - Laura K. Schiraldi
- Department of Biology, University of Rochester, Rochester, New York 14627
- Department of Biology, The College at Brockport, State University of New York, Brockport, New York 14420
| | - Naina Phadnis
- Department of Biology, University of Rochester, Rochester, New York 14627
| | - Garry L. Coles
- Department of Biology, The College at Brockport, State University of New York, Brockport, New York 14420
| | - Rey A. Sia
- Department of Biology, The College at Brockport, State University of New York, Brockport, New York 14420
| | - Elaine A. Sia
- Department of Biology, University of Rochester, Rochester, New York 14627
| |
Collapse
|
80
|
Mileshina D, Ibrahim N, Boesch P, Lightowlers RN, Dietrich A, Weber-Lotfi F. Mitochondrial transfection for studying organellar DNA repair, genome maintenance and aging. Mech Ageing Dev 2011; 132:412-23. [PMID: 21645537 DOI: 10.1016/j.mad.2011.05.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 03/02/2011] [Accepted: 05/21/2011] [Indexed: 12/15/2022]
Abstract
Maintenance of the mitochondrial genome is a major challenge for cells, particularly as they begin to age. Although it is established that organelles possess regular DNA repair pathways, many aspects of these complex processes and of their regulation remain to be investigated. Mitochondrial transfection of isolated organelles and in whole cells with customized DNA synthesized to contain defined lesions has wide prospects for deciphering repair mechanisms in a physiological context. We document here the strategies currently developed to transfer DNA of interest into mitochondria. Methodologies with isolated mitochondria claim to exploit the protein import pathway or the natural competence of the organelles, to permeate the membranes or to use conjugal transfer from bacteria. Besides biolistics, which remains restricted to yeast and Chlamydomonas reinhardtii, nanocarriers or fusion proteins have been explored as methods to target custom DNA into mitochondria in intact cells. In further approaches, whole mitochondria have been transferred into recipient cells. Repair failure or error-prone repair leads to mutations which potentially could be rescued by allotopic expression of proteins. The relevance of the different approaches for the analysis of mitochondrial DNA repair mechanisms and of aging is discussed.
Collapse
Affiliation(s)
- Daria Mileshina
- Institut de Biologie Moléculaire des Plantes, CNRS/Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France
| | | | | | | | | | | |
Collapse
|
81
|
Cytoplasmic male sterility in Drosophila melanogaster associated with a mitochondrial CYTB variant. Heredity (Edinb) 2011; 107:374-6. [PMID: 21407254 DOI: 10.1038/hdy.2011.12] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
|
82
|
Abstract
The essential need for mitochondrial function has been extensively shown to relate to neuronal health. Neurodegeneration and neurodegeneration-related diseases have been associated with multiple mitochondrial dysfunctions. This review highlights key findings related to commonly studied mitochondrial dysfunctions: imbalance of mitochondrial dynamics, mutations in the mitochondrial genome, excessive reactive oxygen species, and misfolded protein associations/interactions with the mitochondria. Future research in mitochondrial function will help elucidate complex neurodegenerative events while impacting both individual and societal health.
Collapse
|
83
|
Rinaldi T, Dallabona C, Ferrero I, Frontali L, Bolotin-Fukuhara M. Mitochondrial diseases and the role of the yeast models. FEMS Yeast Res 2010; 10:1006-22. [PMID: 20946356 DOI: 10.1111/j.1567-1364.2010.00685.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Nowadays, mitochondrial diseases are recognized and studied with much attention and they cannot be considered anymore as 'rare diseases'. Yeast has been an instrumental organism to understand the genetic and molecular aspects of the many roles of mitochondria within the cells. Thanks to the general conservation of mitochondrial genes and pathways between human and yeast, it can also be used to model some diseases. In this review, we focus on the most recent topics, exemplifying those for which yeast models have been especially valuable.
Collapse
Affiliation(s)
- Teresa Rinaldi
- Department of Cell and Developmental Biology, Pasteur Institute-Cenci Bolognetti Foundation, Sapienza University of Rome, Rome, Italy
| | | | | | | | | |
Collapse
|
84
|
Modeling mitochondrial encephalomyopathy in Drosophila. Neurobiol Dis 2010; 40:40-5. [PMID: 20472065 DOI: 10.1016/j.nbd.2010.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/04/2010] [Accepted: 05/06/2010] [Indexed: 11/21/2022] Open
Abstract
Mitochondrial encephalomyopathies are disturbingly complex and devastating diseases, reflecting the underlying importance of the affected organelle. Therapeutic approaches for these diseases remain limited due to a poor understanding of disease pathogenesis resulting largely from a lack of tractable model systems in which to study these diseases. This is especially so for disease conditions resulting from mutations directly affecting the mitochondrial genome. Recent studies using Drosophila to develop genetic models with endogenous mitochondrial mutations suggest the fruit fly will contribute significantly to our understanding of mitochondrial disease pathogenesis and the development of novel therapeutic avenues.
Collapse
|
85
|
Bott NJ, Ophel-Keller KM, Sierp MT, Herdina, Rowling KP, McKay AC, Loo MGK, Tanner JE, Deveney MR. Toward routine, DNA-based detection methods for marine pests. Biotechnol Adv 2010; 28:706-14. [PMID: 20488239 DOI: 10.1016/j.biotechadv.2010.05.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 05/06/2010] [Accepted: 05/11/2010] [Indexed: 01/13/2023]
Abstract
Marine pest incursions can cause significant ongoing damage to aquaculture, biodiversity, fisheries habitat, infrastructure and social amenity. They represent a significant and ongoing economic burden. Marine pests can be introduced by several vectors including aquaculture, aquarium trading, commercial shipping, fishing, floating debris, mining activities and recreational boating. Despite the inherent risks, there is currently relatively little routine surveillance of marine pest species conducted in the majority of countries worldwide. Accurate and rapid identification of marine pest species is central to early detection and management. Traditional techniques (e.g. physical sampling and sorting), have limitations, which has motivated some progress towards the development of molecular diagnostic tools. This review provides a brief account of the techniques traditionally used for detection and describes developments in molecular-based methods for the detection and surveillance of marine pest species. Recent advances provide a platform for the development of practical, specific, sensitive and rapid diagnosis and surveillance tools for marine pests for use in effective prevention and control strategies.
Collapse
Affiliation(s)
- Nathan J Bott
- Aquatic Sciences, South Australian Research and Development Institute, Henley Beach, South Australia, Australia.
| | | | | | | | | | | | | | | | | |
Collapse
|
86
|
Mitochondrial electron transport chain dysfunction during development does not extend lifespan in Drosophila melanogaster. Mech Ageing Dev 2010; 131:156-64. [PMID: 20096722 DOI: 10.1016/j.mad.2010.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 12/22/2009] [Accepted: 01/13/2010] [Indexed: 11/21/2022]
Abstract
Since the initial identification of reactive oxygen species (ROS) as the major factor in aging, many studies have provided evidence for the central role of mitochondria in longevity. A few years ago, an unexpected finding showed that the inactivation of the mitochondrial respiratory chain (MRC) in Caenorhabditis elegans, during the developmental stages only, extended lifespan. Activation of this mitochondrial pathway affecting aging (MIT) is associated with several phenotypic features: increased longevity, increased time of development, decreased fertility/fecundity and reduced adult size. Here, we investigated this pathway in another model organism, Drosophila melanogaster. To assess the role of mitochondrial activity in the Drosophila aging process, we partially inactivated the MRC using RNA interference (RNAi) during larval stages. Developmental perturbation of the respiratory process prolonged development, increased lethality during developmental stage, reduced both fecundity and fertility and slightly reduced individual weight. However, in contrast to the nematode, this genetic intervention either shortened or had no effect on lifespan, depending on the level of gene inactivation. Thus, the effects of MRC disruption during development on aging differ between species. We discuss the possible origins of such differences.
Collapse
|
87
|
Barker PE, Murthy M. Biomarker Validation for Aging: Lessons from mtDNA Heteroplasmy Analyses in Early Cancer Detection. Biomark Insights 2009; 4:165-79. [PMID: 20029650 PMCID: PMC2796862 DOI: 10.4137/bmi.s2253] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The anticipated biological and clinical utility of biomarkers has attracted significant interest recently. Aging and early cancer detection represent areas active in the search for predictive and prognostic biomarkers. While applications differ, overlapping biological features, analytical technologies and specific biomarker analytes bear comparison. Mitochondrial DNA (mtDNA) as a biomarker in both biological models has been evaluated. However, it remains unclear whether mtDNA changes in aging and cancer represent biological relationships that are causal, incidental, or a combination of both. This article focuses on evaluation of mtDNA-based biomarkers, emerging strategies for quantitating mtDNA admixtures, and how current understanding of mtDNA in aging and cancer evolves with introduction of new technologies. Whether for cancer or aging, lessons from mtDNA based biomarker evaluations are several. Biological systems are inherently dynamic and heterogeneous. Detection limits for mtDNA sequencing technologies differ among methods for low-level DNA sequence admixtures in healthy and diseased states. Performance metrics of analytical mtDNA technology should be validated prior to application in heterogeneous biologically-based systems. Critical in evaluating biomarker performance is the ability to distinguish measurement system variance from inherent biological variance, because it is within the latter that background healthy variability as well as high-value, disease-specific information reside.
Collapse
Affiliation(s)
- Peter E. Barker
- Bioassay Methods Group, Biochemical Sciences Division, Bldg 227/B248, NIST, 100 Bureau Drive, Gaithersburg, Maryland
| | - Mahadev Murthy
- Division of Aging Biology (DAB), National Institute on Aging, 7201 Wisconsin Ave., GW 2C231, Bethesda, MD 20892.
;
| |
Collapse
|
88
|
Diaz F. Cytochrome c oxidase deficiency: patients and animal models. Biochim Biophys Acta Mol Basis Dis 2009; 1802:100-10. [PMID: 19682572 DOI: 10.1016/j.bbadis.2009.07.013] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 07/30/2009] [Accepted: 07/31/2009] [Indexed: 12/17/2022]
Abstract
Cytochrome c oxidase (COX) deficiencies are one of the most common defects of the respiratory chain found in mitochondrial diseases. COX is a multimeric inner mitochondrial membrane enzyme formed by subunits encoded by both the nuclear and the mitochondrial genome. COX biosynthesis requires numerous assembly factors that do not form part of the final complex but participate in prosthetic group synthesis and metal delivery in addition to membrane insertion and maturation of COX subunits. Human diseases associated with COX deficiency including encephalomyopathies, Leigh syndrome, hypertrophic cardiomyopathies, and fatal lactic acidosis are caused by mutations in COX subunits or assembly factors. In the last decade, numerous animal models have been created to understand the pathophysiology of COX deficiencies and the function of assembly factors. These animal models, ranging from invertebrates to mammals, in most cases mimic the pathological features of the human diseases.
Collapse
Affiliation(s)
- Francisca Diaz
- Department of Neurology, University of Miami Miller School of Medicine, 1095 NW 14th Terrace, Miami, Florida 33136, USA.
| |
Collapse
|
89
|
Cox RT, Spradling AC. Clueless, a conserved Drosophila gene required for mitochondrial subcellular localization, interacts genetically with parkin. Dis Model Mech 2009; 2:490-9. [PMID: 19638420 PMCID: PMC2737057 DOI: 10.1242/dmm.002378] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Parkinson's disease has been linked to altered mitochondrial function. Mutations in parkin (park), the Drosophila ortholog of a human gene that is responsible for many familial cases of Parkinson's disease, shorten life span, abolish fertility and disrupt mitochondrial structure. However, the role played by Park in mitochondrial function remains unclear. Here, we describe a novel Drosophila gene, clueless (clu), which encodes a highly conserved tetratricopeptide repeat protein that is related closely to the CluA protein of Dictyostelium, Clu1 of Saccharomyces cerevisiae and to similar proteins in diverse metazoan eukaryotes from Arabidopsis to humans. Like its orthologs, loss of Drosophila clu causes mitochondria to cluster within cells. We find that strong clu mutations resemble park mutations in their effects on mitochondrial function and that the two genes interact genetically. Conversely, mitochondria in park homozygotes become highly clustered. We propose that Clu functions in a novel pathway that positions mitochondria within the cell based on their physiological state. Disruption of the Clu pathway may enhance oxidative damage, alter gene expression, cause mitochondria to cluster at microtubule plus ends, and lead eventually to mitochondrial failure.
Collapse
Affiliation(s)
- Rachel T Cox
- Department of Embryology/Howard Hughes Medical Institute, Carnegie Institution, 3520 San Martin Drive, Baltimore, MD 21218, USA
| | | |
Collapse
|
90
|
Current World Literature. Curr Opin Lipidol 2009; 20:135-42. [PMID: 19276892 DOI: 10.1097/mol.0b013e32832a7e09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
91
|
In Brief. Nat Rev Genet 2008. [DOI: 10.1038/nrg2433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|