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Zhang R, Hou T, Cheng H, Wang X. NDUFAB1 protects against obesity and insulin resistance by enhancing mitochondrial metabolism. FASEB J 2019; 33:13310-13322. [PMID: 31530015 PMCID: PMC6894049 DOI: 10.1096/fj.201901117rr] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mitochondria are fundamental organelles for cellular and systemic metabolism, and their dysfunction has been implicated in the development of diverse metabolic diseases. Boosted mitochondrial metabolism might be able to protect against metabolic stress and prevent metabolic disorders. Here we show that NADH:ubiquinone oxidoreductase (NDU)-FAB1, also known as mitochondrial acyl carrier protein, acts as a novel enhancer of mitochondrial metabolism and protects against obesity and insulin resistance. Mechanistically, NDUFAB1 coordinately enhances lipoylation and activation of pyruvate dehydrogenase mediated by the mitochondrial fatty acid synthesis pathway and increases the assembly of respiratory complexes and supercomplexes. Skeletal muscle-specific ablation of NDUFAB1 causes systemic disruption of glucose homeostasis and defective insulin signaling, leading to growth arrest and early death within 5 postnatal days. In contrast, NDUFAB1 overexpression effectively protects mice against obesity and insulin resistance when the animals are challenged with a high-fat diet. Our findings indicate that NDUFAB1 could be a novel mitochondrial target to prevent obesity and insulin resistance by enhancing mitochondrial metabolism.-Zhang, R., Hou, T., Cheng, H., Wang, X. NDUFAB1 protects against obesity and insulin resistance by enhancing mitochondrial metabolism.
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Affiliation(s)
- Rufeng Zhang
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, China
| | - Tingting Hou
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, China
| | - Heping Cheng
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, China
| | - Xianhua Wang
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, China
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102
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Letts JA, Fiedorczuk K, Degliesposti G, Skehel M, Sazanov LA. Structures of Respiratory Supercomplex I+III 2 Reveal Functional and Conformational Crosstalk. Mol Cell 2019; 75:1131-1146.e6. [PMID: 31492636 PMCID: PMC6926478 DOI: 10.1016/j.molcel.2019.07.022] [Citation(s) in RCA: 119] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 06/10/2019] [Accepted: 07/15/2019] [Indexed: 11/02/2022]
Abstract
The mitochondrial electron transport chain complexes are organized into supercomplexes (SCs) of defined stoichiometry, which have been proposed to regulate electron flux via substrate channeling. We demonstrate that CoQ trapping in the isolated SC I+III2 limits complex (C)I turnover, arguing against channeling. The SC structure, resolved at up to 3.8 Å in four distinct states, suggests that CoQ oxidation may be rate limiting because of unequal access of CoQ to the active sites of CIII2. CI shows a transition between "closed" and "open" conformations, accompanied by the striking rotation of a key transmembrane helix. Furthermore, the state of CI affects the conformational flexibility within CIII2, demonstrating crosstalk between the enzymes. CoQ was identified at only three of the four binding sites in CIII2, suggesting that interaction with CI disrupts CIII2 symmetry in a functionally relevant manner. Together, these observations indicate a more nuanced functional role for the SCs.
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Affiliation(s)
- James A Letts
- Institute of Science and Technology Austria, Klosterneuberg 3400, Austria; Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616, USA
| | - Karol Fiedorczuk
- Institute of Science and Technology Austria, Klosterneuberg 3400, Austria; Laboratory of Membrane Biophysics and Biology, The Rockefeller University, New York, NY 10065, USA
| | | | - Mark Skehel
- MRC Laboratory of Molecular Biology, Cambridge CB2 OQH, UK
| | - Leonid A Sazanov
- Institute of Science and Technology Austria, Klosterneuberg 3400, Austria.
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103
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Nobiletin fortifies mitochondrial respiration in skeletal muscle to promote healthy aging against metabolic challenge. Nat Commun 2019; 10:3923. [PMID: 31462679 PMCID: PMC6713763 DOI: 10.1038/s41467-019-11926-y] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 08/13/2019] [Indexed: 12/31/2022] Open
Abstract
Circadian disruption aggravates age-related decline and mortality. However, it remains unclear whether circadian enhancement can retard aging in mammals. We previously reported that the small molecule Nobiletin (NOB) activates ROR (retinoid acid receptor-related orphan receptor) nuclear receptors to potentiate circadian oscillation and protect against metabolic dysfunctions. Here we show that NOB significantly improves metabolic fitness in naturally aged mice fed with a regular diet (RD). Furthermore, NOB enhances healthy aging in mice fed with a high-fat diet (HF). In HF skeletal muscle, the NOB-ROR axis broadly activates genes for mitochondrial respiratory chain complexes (MRCs) and fortifies MRC activity and architecture, including Complex II activation and supercomplex formation. These mechanisms coordinately lead to a dichotomous mitochondrial optimization, namely increased ATP production and reduced ROS levels. Together, our study illustrates a focal mechanism by a clock-targeting pharmacological agent to optimize skeletal muscle mitochondrial respiration and promote healthy aging in metabolically stressed mammals. The small molecule Nobiletin enhances circadian rhythms and protects against obesity-associated metabolic dysfunction in mice. Here the authors test its effect on health and lifespan, reporting that circadian enhancement promotes fitness and healthy aging in metabolically challenged mice.
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104
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BK Ca ( Slo) Channel Regulates Mitochondrial Function and Lifespan in Drosophila melanogaster. Cells 2019; 8:cells8090945. [PMID: 31438578 PMCID: PMC6770356 DOI: 10.3390/cells8090945] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/13/2019] [Accepted: 08/20/2019] [Indexed: 12/20/2022] Open
Abstract
BKCa channels, originally discovered in Drosophila melanogaster as slowpoke (slo), are recognized for their roles in cellular and organ physiology. Pharmacological approaches implicated BKCa channels in cellular and organ protection possibly for their ability to modulate mitochondrial function. However, the direct role of BKCa channels in regulating mitochondrial structure and function is not deciphered. Here, we demonstrate that BKCa channels are present in fly mitochondria, and slo mutants show structural and functional defects in mitochondria. slo mutants display an increase in reactive oxygen species and the modulation of ROS affected their survival. We also found that the absence of BKCa channels reduced the lifespan of Drosophila, and overexpression of human BKCa channels in flies extends life span in males. Our study establishes the presence of BKCa channels in mitochondria of Drosophila and ascertains its novel physiological role in regulating mitochondrial structural and functional integrity, and lifespan.
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105
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Hou T, Zhang R, Jian C, Ding W, Wang Y, Ling S, Ma Q, Hu X, Cheng H, Wang X. NDUFAB1 confers cardio-protection by enhancing mitochondrial bioenergetics through coordination of respiratory complex and supercomplex assembly. Cell Res 2019; 29:754-766. [PMID: 31366990 PMCID: PMC6796901 DOI: 10.1038/s41422-019-0208-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 07/02/2019] [Indexed: 01/09/2023] Open
Abstract
The impairment of mitochondrial bioenergetics, often coupled with exaggerated reactive oxygen species (ROS) production, is a fundamental disease mechanism in organs with a high demand for energy, including the heart. Building a more robust and safer cellular powerhouse holds the promise for protecting these organs in stressful conditions. Here, we demonstrate that NADH:ubiquinone oxidoreductase subunit AB1 (NDUFAB1), also known as mitochondrial acyl carrier protein, acts as a powerful cardio-protector by conferring greater capacity and efficiency of mitochondrial energy metabolism. In particular, NDUFAB1 not only serves as a complex I subunit, but also coordinates the assembly of respiratory complexes I, II, and III, and supercomplexes, through regulating iron-sulfur biosynthesis and complex I subunit stability. Cardiac-specific deletion of Ndufab1 in mice caused defective bioenergetics and elevated ROS levels, leading to progressive dilated cardiomyopathy and eventual heart failure and sudden death. Overexpression of Ndufab1 effectively enhanced mitochondrial bioenergetics while limiting ROS production and protected the heart against ischemia-reperfusion injury. Together, our findings identify that NDUFAB1 is a crucial regulator of mitochondrial energy and ROS metabolism through coordinating the assembly of respiratory complexes and supercomplexes, and thus provide a potential therapeutic target for the prevention and treatment of heart failure.
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Affiliation(s)
- Tingting Hou
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Rufeng Zhang
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Chongshu Jian
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Wanqiu Ding
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Yanru Wang
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Shukuan Ling
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Qi Ma
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Xinli Hu
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China
| | - Heping Cheng
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China.
| | - Xianhua Wang
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing, 100871, China.
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106
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Marco-Brualla J, Al-Wasaby S, Soler R, Romanos E, Conde B, Justo-Méndez R, Enríquez JA, Fernández-Silva P, Martínez-Lostao L, Villalba M, Moreno-Loshuertos R, Anel A. Mutations in the ND2 Subunit of Mitochondrial Complex I Are Sufficient to Confer Increased Tumorigenic and Metastatic Potential to Cancer Cells. Cancers (Basel) 2019; 11:E1027. [PMID: 31330915 PMCID: PMC6678765 DOI: 10.3390/cancers11071027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/16/2019] [Accepted: 07/18/2019] [Indexed: 11/17/2022] Open
Abstract
Multiprotein complexes of the mitochondrial electron transport chain form associations to generate supercomplexes. The relationship between tumor cell ability to assemble mitochondrial supercomplexes, tumorigenesis and metastasis has not been studied thoroughly. The mitochondrial and metabolic differences between L929dt cells, which lost matrix attachment and MHC-I expression, and their parental cell line L929, were analyzed. L929dt cells have lower capacity to generate energy through OXPHOS and lower respiratory capacity than parental L929 cells. Most importantly, L929dt cells show defects in mitochondrial supercomplex assembly, especially in those that contain complex I. These defects correlate with mtDNA mutations in L929dt cells at the ND2 subunit of complex I and are accompanied by a glycolytic shift. In addition, L929dt cells show higher in vivo tumorigenic and metastatic potential than the parental cell line. Cybrids with L929dt mitochondria in L929 nuclear background reproduce all L929dt properties, demonstrating that mitochondrial mutations are responsible for the aggressive tumor phenotype. In spite of their higher tumorigenic potential, L929dt or mitochondrial L929dt cybrid cells are sensitive both in vitro and in vivo to the PDK1 inhibitor dichloroacetate, which favors OXPHOS, suggesting benefits for the use of metabolic inhibitors in the treatment of especially aggressive tumors.
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Affiliation(s)
- Joaquín Marco-Brualla
- Immunity, Cancer & Stem Cells Group, Department Biochemistry and Molecular and Cell Biology, Faculty of Sciences, Campus San Francisco Square, Aragón Health Research Institute (IIS Aragón), University of Zaragoza, E-50009 Zaragoza, Spain
| | - Sameer Al-Wasaby
- Immunity, Cancer & Stem Cells Group, Department Biochemistry and Molecular and Cell Biology, Faculty of Sciences, Campus San Francisco Square, Aragón Health Research Institute (IIS Aragón), University of Zaragoza, E-50009 Zaragoza, Spain
| | - Ruth Soler
- Immunity, Cancer & Stem Cells Group, Department Biochemistry and Molecular and Cell Biology, Faculty of Sciences, Campus San Francisco Square, Aragón Health Research Institute (IIS Aragón), University of Zaragoza, E-50009 Zaragoza, Spain
| | - Eduardo Romanos
- Aragón Health Research Institute (IIS Aragón), Center for Research in Biomedicine, E-50009 Zaragoza, Spain
| | - Blanca Conde
- Department of Human Anatomy and Histology, Faculty of Medicine, Campus San Francisco Square, University of Zaragoza, E-50009 Zaragoza, Spain
| | | | - José A Enríquez
- Carlos III National Center for Cardiovascular Research, 28029 Madrid, Spain
| | - Patricio Fernández-Silva
- GENOXPHOS Group, Department Biochemistry and Molecular and Cell Biology, Faculty of Sciences, Campus San Francisco Square, Biocomputation and Complex Systems Physics Institute (BIFI), University of Zaragoza, E-50009 Zaragoza, Spain
| | | | - Martín Villalba
- The National Institute of Biomedical Research (INSERM), Centre Hospitalier Universitaire de Montpellier, The University of Montpellier, The Institute for Regenerative Medicine and Biotherapy, 34090 Montpellier, France
- IRMB, CHU Montpellier, 34090 Montpellier, France
| | - Raquel Moreno-Loshuertos
- GENOXPHOS Group, Department Biochemistry and Molecular and Cell Biology, Faculty of Sciences, Campus San Francisco Square, Biocomputation and Complex Systems Physics Institute (BIFI), University of Zaragoza, E-50009 Zaragoza, Spain.
| | - Alberto Anel
- Immunity, Cancer & Stem Cells Group, Department Biochemistry and Molecular and Cell Biology, Faculty of Sciences, Campus San Francisco Square, Aragón Health Research Institute (IIS Aragón), University of Zaragoza, E-50009 Zaragoza, Spain.
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107
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Mitochondrial respirasome works as a single unit and the cross-talk between complexes I, III 2 and IV stimulates NADH dehydrogenase activity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:618-627. [PMID: 31251900 DOI: 10.1016/j.bbabio.2019.06.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 06/20/2019] [Accepted: 06/22/2019] [Indexed: 11/20/2022]
Abstract
Ustilago maydis is an aerobic basidiomycete that depends on oxidative phosphorylation for its ATP supply, pointing to the mitochondrion as a key player in its energy metabolism. Mitochondrial respiratory complexes I, III2, and IV occur in supramolecular structures named respirasome. In this work, we characterized the subunit composition and the kinetics of NADH:Q oxidoreductase activity of the digitonine-solubilized respirasome (1600 kDa) and the free-complex I (990 kDa). In the presence of 2,6-dimethoxy-1,4-benzoquinone (DBQ) and cytochrome c, both the respirasome NADH:O2 and the NADH:DBQ oxidoreductase activities were inhibited by rotenone, antimycin A or cyanide. A value of 2.4 for the NADH oxidized/oxygen reduced ratio was determined for the respirasome activity, while ROS production was less than 0.001% of the oxygen consumption rate. Analysis of the NADH:DBQ oxidoreductase activity showed that respirasome was 3-times more active and showed higher affinity than free-complex I. The results suggest that the contacts between complexes I, III2 and IV in the respirasome increase the catalytic efficiency of complex I and regulate its activity to prevent ROS production.
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108
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Wang Y, Palmfeldt J, Gregersen N, Makhov AM, Conway JF, Wang M, McCalley SP, Basu S, Alharbi H, St Croix C, Calderon MJ, Watkins S, Vockley J. Mitochondrial fatty acid oxidation and the electron transport chain comprise a multifunctional mitochondrial protein complex. J Biol Chem 2019; 294:12380-12391. [PMID: 31235473 DOI: 10.1074/jbc.ra119.008680] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 06/10/2019] [Indexed: 12/11/2022] Open
Abstract
Three mitochondrial metabolic pathways are required for efficient energy production in eukaryotic cells: the electron transfer chain (ETC), fatty acid β-oxidation (FAO), and the tricarboxylic acid cycle. The ETC is organized into inner mitochondrial membrane supercomplexes that promote substrate channeling and catalytic efficiency. Although previous studies have suggested functional interaction between FAO and the ETC, their physical interaction has never been demonstrated. In this study, using blue native gel and two-dimensional electrophoreses, nano-LC-MS/MS, immunogold EM, and stimulated emission depletion microscopy, we show that FAO enzymes physically interact with ETC supercomplexes at two points. We found that the FAO trifunctional protein (TFP) interacts with the NADH-binding domain of complex I of the ETC, whereas the electron transfer enzyme flavoprotein dehydrogenase interacts with ETC complex III. Moreover, the FAO enzyme very-long-chain acyl-CoA dehydrogenase physically interacted with TFP, thereby creating a multifunctional energy protein complex. These findings provide a first view of an integrated molecular architecture for the major energy-generating pathways in mitochondria that ensures the safe transfer of unstable reducing equivalents from FAO to the ETC. They also offer insight into clinical ramifications for individuals with genetic defects in these pathways.
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Affiliation(s)
- Yudong Wang
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Aarhus University Hospital, DK-8200 Aarhus, Denmark
| | - Niels Gregersen
- Research Unit for Molecular Medicine, Aarhus University Hospital, DK-8200 Aarhus, Denmark
| | - Alexander M Makhov
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - James F Conway
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Meicheng Wang
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Stephen P McCalley
- Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania 15261
| | - Shrabani Basu
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Hana Alharbi
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Claudette St Croix
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Michael J Calderon
- Center for Rare Disease Therapy, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15224
| | - Simon Watkins
- Center for Rare Disease Therapy, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15224
| | - Jerry Vockley
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261; Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania 15261; Center for Rare Disease Therapy, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15224.
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109
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Stay Fit, Stay Young: Mitochondria in Movement: The Role of Exercise in the New Mitochondrial Paradigm. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:7058350. [PMID: 31320983 PMCID: PMC6607712 DOI: 10.1155/2019/7058350] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/23/2019] [Accepted: 05/08/2019] [Indexed: 12/29/2022]
Abstract
Skeletal muscles require the proper production and distribution of energy to sustain their work. To ensure this requirement is met, mitochondria form large networks within skeletal muscle cells, and during exercise, they can enhance their functions. In the present review, we discuss recent findings on exercise-induced mitochondrial adaptations. We emphasize the importance of mitochondrial biogenesis, morphological changes, and increases in respiratory supercomplex formation as mechanisms triggered by exercise that may increase the function of skeletal muscles. Finally, we highlight the possible effects of nutraceutical compounds on mitochondrial performance during exercise and outline the use of exercise as a therapeutic tool in noncommunicable disease prevention. The resulting picture shows that the modulation of mitochondrial activity by exercise is not only fundamental for physical performance but also a key point for whole-organism well-being.
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110
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Mitochondrial Dysfunctions: A Thread Sewing Together Alzheimer's Disease, Diabetes, and Obesity. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:7210892. [PMID: 31316720 PMCID: PMC6604285 DOI: 10.1155/2019/7210892] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/20/2019] [Accepted: 05/21/2019] [Indexed: 02/03/2023]
Abstract
Metabolic disorders are severe and chronic impairments of the health of many people and represent a challenge for the society as a whole that has to deal with an ever-increasing number of affected individuals. Among common metabolic disorders are Alzheimer's disease, obesity, and type 2 diabetes. These disorders do not have a univocal genetic cause but rather can result from the interaction of multiple genes, lifestyle, and environmental factors. Mitochondrial alterations have emerged as a feature common to all these disorders, underlining perhaps an impaired coordination between cellular needs and mitochondrial responses that could contribute to their development and/or progression.
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111
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Baker N, Patel J, Khacho M. Linking mitochondrial dynamics, cristae remodeling and supercomplex formation: How mitochondrial structure can regulate bioenergetics. Mitochondrion 2019; 49:259-268. [PMID: 31207408 DOI: 10.1016/j.mito.2019.06.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 05/18/2019] [Accepted: 06/06/2019] [Indexed: 01/21/2023]
Abstract
The dynamic and fluid nature of mitochondria allows for modifications in mitochondrial shape, connectivity and cristae architecture. The precise balance of mitochondrial dynamics is among the most critical features in the control of mitochondrial function. In the past few years, mitochondrial shape has emerged as a key regulatory factor in the determination of the bioenergetic capacity of cells. This is mostly due to the recent discoveries linking changes in cristae organization with supercomplex assembly of the electron transport chain (ETC), also defined as the formation of respirosomes. Here we will review the most current advances demonstrating the impact of mitochondrial dynamics and cristae shape on oxidative metabolism, respiratory efficiency, and redox state. Furthermore, we will discuss the implications of mitochondrial dynamics and supercomplex assembly under physiological and pathological conditions.
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Affiliation(s)
- Nicole Baker
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology (OISB), Center for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada
| | - Jeel Patel
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology (OISB), Center for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada
| | - Mireille Khacho
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology (OISB), Center for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada.
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112
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Jang S, Javadov S. Elucidating the contribution of ETC complexes I and II to the respirasome formation in cardiac mitochondria. Sci Rep 2018; 8:17732. [PMID: 30531981 PMCID: PMC6286307 DOI: 10.1038/s41598-018-36040-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 11/14/2018] [Indexed: 12/17/2022] Open
Abstract
Mitochondrial electron transport chain (ETC) plays a central role in ATP synthesis, and its dysfunction is associated with human diseases. Recent studies revealed that individual ETC complexes are assembled into supercomplexes. The main supercomplex, respirasome composed of complexes I, III, and IV has been suggested to improve electron channeling and control ROS production, maintain the structural integrity of ETC complexes and prevent protein aggregation in the inner mitochondrial membrane. However, many questions related to the structural organization of the respirasome, particularly, a possible role of complexes I and II in respirasome formation remain unclear. Here, we investigated whether genetic and pharmacological inhibition of complexes I and II affect respirasome assembly in cardioblast cells and isolated cardiac mitochondria. Pharmacological inhibition of the enzymatic activity of complexes I and II stimulated disruption of the respirasome. Likewise, knockdown of the complex I subunit NDUFA11 stimulated dissociation of respirasome and reduced the activity of complexes I, III, and IV. However, silencing of the membrane-anchored SDHC subunit of complex II had no effect on the respirasome assembly but reduced the activity of complexes II and IV. Downregulation of NDUFA11 or SDHC reduced ATP production and increased mitochondrial ROS production. Overall, these studies, for the first time, provide biochemical evidence that the complex I activity, and the NDUFA11 subunit are important for assembly and stability of the respirasome. The SDHC subunit of complex II is not involved in the respirasome however the complex may play a regulatory role in respirasome formation.
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Affiliation(s)
- Sehwan Jang
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, PR, 00936-5067, USA
| | - Sabzali Javadov
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, PR, 00936-5067, USA.
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113
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Cogliati S, Lorenzi I, Rigoni G, Caicci F, Soriano ME. Regulation of Mitochondrial Electron Transport Chain Assembly. J Mol Biol 2018; 430:4849-4873. [DOI: 10.1016/j.jmb.2018.09.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/20/2018] [Accepted: 09/25/2018] [Indexed: 12/26/2022]
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114
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Nadeau L, Patten DA, Caron A, Garneau L, Pinault-Masson E, Foretz M, Haddad P, Anderson BG, Quinn LS, Jardine K, McBurney MW, Pistilli EE, Harper ME, Aguer C. IL-15 improves skeletal muscle oxidative metabolism and glucose uptake in association with increased respiratory chain supercomplex formation and AMPK pathway activation. Biochim Biophys Acta Gen Subj 2018; 1863:395-407. [PMID: 30448294 DOI: 10.1016/j.bbagen.2018.10.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 10/05/2018] [Accepted: 10/16/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND IL-15 is believed to play a role in the beneficial impact of exercise on muscle energy metabolism. However, previous studies have generally used supraphysiological levels of IL-15 that do not represent contraction-induced IL-15 secretion. METHODS L6 myotubes were treated acutely (3 h) and chronically (48 h) with concentrations of IL-15 mimicking circulating (1-10 pg/ml) and muscle interstitial (100 pg/ml -20 ng/ml) IL-15 levels with the aim to better understand its autocrine/paracrine role on muscle glucose uptake and mitochondrial function. RESULTS Acute exposure to IL-15 levels representing muscle interstitial IL-15 increased basal glucose uptake without affecting insulin sensitivity. This was accompanied by increased mitochondrial oxidative functions in association with increased AMPK pathway and formation of complex III-containing supercomplexes. Conversely, chronic IL-15 exposure resulted in a biphasic effect on mitochondrial oxidative functions and ETC supercomplex formation was increased with low IL-15 levels but decreased with higher IL-15 concentrations. The AMPK pathway was activated only by high levels of chronic IL-15 treatment. Similar results were obtained in skeletal muscle from muscle-specific IL-15 overexpressing mice that show very high circulating IL-15 levels. CONCLUSIONS Acute IL-15 treatment that mimics local IL-15 concentrations enhances muscle glucose uptake and mitochondrial oxidative functions. That mitochondria respond differently to different levels of IL-15 during chronic treatments indicates that IL-15 might activate two different pathways in muscle depending on IL-15 concentrations. GENERAL SIGNIFICANCE Our results suggest that IL-15 may act in an autocrine/paracrine fashion and be, at least in part, involved in the positive effect of exercise on muscle energy metabolism.
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Affiliation(s)
- L Nadeau
- Institut du Savoir Montfort - Recherche, Ottawa, ON, Canada; University of Ottawa, Faculty of Medicine, Department of Biochemistry, Microbiology, and Immunology, Ottawa, ON, Canada
| | - D A Patten
- University of Ottawa, Faculty of Medicine, Department of Biochemistry, Microbiology, and Immunology, Ottawa, ON, Canada
| | - A Caron
- Institut du Savoir Montfort - Recherche, Ottawa, ON, Canada; University of Ottawa, Faculty of Medicine, Department of Biochemistry, Microbiology, and Immunology, Ottawa, ON, Canada
| | - L Garneau
- Institut du Savoir Montfort - Recherche, Ottawa, ON, Canada; University of Ottawa, Faculty of Medicine, Department of Biochemistry, Microbiology, and Immunology, Ottawa, ON, Canada
| | - E Pinault-Masson
- Institut du Savoir Montfort - Recherche, Ottawa, ON, Canada; University of Ottawa, Faculty of Science, Ottawa, ON, Canada
| | - M Foretz
- INSERM, U1016, Institut Cochin, Paris 75014, France; CNRS, UMR8104, Paris 75014, France; Université Paris Descartes, Sorbonne Paris Cité, Paris 75014, France
| | - P Haddad
- Institut du Savoir Montfort - Recherche, Ottawa, ON, Canada; University of Ottawa, Faculty of Science, Ottawa, ON, Canada
| | - B G Anderson
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
| | - L S Quinn
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
| | - K Jardine
- Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - M W McBurney
- Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - E E Pistilli
- West Virginia University School of Medicine, Morgantown, WV, United States
| | - M E Harper
- University of Ottawa, Faculty of Medicine, Department of Biochemistry, Microbiology, and Immunology, Ottawa, ON, Canada
| | - C Aguer
- Institut du Savoir Montfort - Recherche, Ottawa, ON, Canada; University of Ottawa, Faculty of Medicine, Department of Biochemistry, Microbiology, and Immunology, Ottawa, ON, Canada.
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115
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Lobo-Jarne T, Nývltová E, Pérez-Pérez R, Timón-Gómez A, Molinié T, Choi A, Mourier A, Fontanesi F, Ugalde C, Barrientos A. Human COX7A2L Regulates Complex III Biogenesis and Promotes Supercomplex Organization Remodeling without Affecting Mitochondrial Bioenergetics. Cell Rep 2018; 25:1786-1799.e4. [PMID: 30428348 PMCID: PMC6286155 DOI: 10.1016/j.celrep.2018.10.058] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 10/08/2018] [Accepted: 10/15/2018] [Indexed: 12/27/2022] Open
Abstract
The mitochondrial respiratory chain is organized in a dynamic set of supercomplexes (SCs). The COX7A2L protein is essential for mammalian SC III2+IV assembly. However, its function in respirasome (SCs I+III2+IVn) biogenesis remains controversial. To unambiguously determine the COX7A2L role, we generated COX7A2L-knockout (COX7A2L-KO) HEK293T and U87 cells. COX7A2L-KO cells lack SC III2+IV but have enhanced complex III steady-state levels, activity, and assembly rate, normal de novo complex IV biogenesis, and delayed respirasome formation. Nonetheless, the KOs have normal respirasome steady-state levels, and only larger structures (SCs I1-2+III2+IV2-n or megacomplexes) were undetected. Functional substrate-driven competition assays showed normal mitochondrial respiration in COX7A2L-KO cells in standard and nutritional-, environmental-, and oxidative-stress-challenging conditions. We conclude that COX7A2L establishes a regulatory checkpoint for the biogenesis of CIII2 and specific SCs, but the COX7A2L-dependent MRC remodeling is essential neither to maintain mitochondrial bioenergetics nor to cope with acute cellular stresses.
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Affiliation(s)
- Teresa Lobo-Jarne
- Instituto de Investigación Hospital 12 de Octubre (i+12), 28041 Madrid, Spain
| | - Eva Nývltová
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Rafael Pérez-Pérez
- Instituto de Investigación Hospital 12 de Octubre (i+12), 28041 Madrid, Spain
| | - Alba Timón-Gómez
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Thibaut Molinié
- Université de Bordeaux and Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Bordeaux, France
| | - Austin Choi
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Arnaud Mourier
- Université de Bordeaux and Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Bordeaux, France
| | - Flavia Fontanesi
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Cristina Ugalde
- Instituto de Investigación Hospital 12 de Octubre (i+12), 28041 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), U723, 28029 Madrid, Spain.
| | - Antoni Barrientos
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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116
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Chaussenot A, Rouzier C, Fragaki K, Sacconi S, Ait-El-Mkadem S, Paquis-Flucklinger V, Bannwarth S. MT-CYB deletion in an encephalomyopathy with hyperintensity of middle cerebellar peduncles. NEUROLOGY-GENETICS 2018; 4:e268. [PMID: 30294674 PMCID: PMC6168751 DOI: 10.1212/nxg.0000000000000268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/21/2018] [Indexed: 11/16/2022]
Affiliation(s)
| | - Cécile Rouzier
- Université Côte d'Azur, CHU de Nice, Inserm, CNRS, IRCAN, France
| | | | - Sabrina Sacconi
- Université Côte d'Azur, CHU de Nice, Inserm, CNRS, IRCAN, France
| | | | | | - Sylvie Bannwarth
- Université Côte d'Azur, CHU de Nice, Inserm, CNRS, IRCAN, France
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117
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Fedor JG, Hirst J. Mitochondrial Supercomplexes Do Not Enhance Catalysis by Quinone Channeling. Cell Metab 2018; 28:525-531.e4. [PMID: 29937372 PMCID: PMC6125145 DOI: 10.1016/j.cmet.2018.05.024] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 05/14/2018] [Accepted: 05/24/2018] [Indexed: 12/12/2022]
Abstract
Mitochondrial respiratory supercomplexes, comprising complexes I, III, and IV, are the minimal functional units of the electron transport chain. Assembling the individual complexes into supercomplexes may stabilize them, provide greater spatiotemporal control of respiration, or, controversially, confer kinetic advantages through the sequestration of local quinone and cytochrome c pools (substrate channeling). Here, we have incorporated an alternative quinol oxidase (AOX) into mammalian heart mitochondrial membranes to introduce a competing pathway for quinol oxidation and test for channeling. AOX substantially increases the rate of NADH oxidation by O2 without affecting the membrane integrity, the supercomplexes, or NADH-linked oxidative phosphorylation. Therefore, the quinol generated in supercomplexes by complex I is reoxidized more rapidly outside the supercomplex by AOX than inside the supercomplex by complex III. Our results demonstrate that quinone and quinol diffuse freely in and out of supercomplexes: substrate channeling does not occur and is not required to support respiration.
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Affiliation(s)
- Justin G Fedor
- The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Judy Hirst
- The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
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118
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Quintana-Cabrera R, Quirin C, Glytsou C, Corrado M, Urbani A, Pellattiero A, Calvo E, Vázquez J, Enríquez JA, Gerle C, Soriano ME, Bernardi P, Scorrano L. The cristae modulator Optic atrophy 1 requires mitochondrial ATP synthase oligomers to safeguard mitochondrial function. Nat Commun 2018; 9:3399. [PMID: 30143614 PMCID: PMC6109181 DOI: 10.1038/s41467-018-05655-x] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 07/18/2018] [Indexed: 12/16/2022] Open
Abstract
It is unclear how the mitochondrial fusion protein Optic atrophy 1 (OPA1), which inhibits cristae remodeling, protects from mitochondrial dysfunction. Here we identify the mitochondrial F1Fo-ATP synthase as the effector of OPA1 in mitochondrial protection. In OPA1 overexpressing cells, the loss of proton electrochemical gradient caused by respiratory chain complex III inhibition is blunted and this protection is abolished by the ATP synthase inhibitor oligomycin. Mechanistically, OPA1 and ATP synthase can interact, but recombinant OPA1 fails to promote oligomerization of purified ATP synthase reconstituted in liposomes, suggesting that OPA1 favors ATP synthase oligomerization and reversal activity by modulating cristae shape. When ATP synthase oligomers are genetically destabilized by silencing the key dimerization subunit e, OPA1 is no longer able to preserve mitochondrial function and cell viability upon complex III inhibition. Thus, OPA1 protects mitochondria from respiratory chain inhibition by stabilizing cristae shape and favoring ATP synthase oligomerization. Mitochondrial cristae shape influences apoptosis and respiration. Here the authors show that the mitochondrial fusion protein OPA1 protects mitochondria from dysfunction by promoting ATP synthase oligomerization and reversal activity.
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Affiliation(s)
- Rubén Quintana-Cabrera
- Venetian Institute of Molecular Medicine, 35129, Padua, Italy.,Department of Biology, University of Padua, 35121, Padua, Italy.,University of Salamanca, Consejo Superior de Investigaciones Científicas CSIC, Institute of Functional Biology and Genomics, Salamanca, 37007, Spain.,Institute of Biomedical Research of Salamanca, University Hospital of Salamanca, University of Salamanca, CSIC, 37007, Salamanca, Spain.,CIBERFES, Institute of Health Carlos III, Madrid, Spain
| | - Charlotte Quirin
- Venetian Institute of Molecular Medicine, 35129, Padua, Italy.,Department of Biology, University of Padua, 35121, Padua, Italy
| | - Christina Glytsou
- Venetian Institute of Molecular Medicine, 35129, Padua, Italy.,Department of Biology, University of Padua, 35121, Padua, Italy.,Department of Pathology, NYU School of Medicine, 10016, New York, NY, USA
| | - Mauro Corrado
- Venetian Institute of Molecular Medicine, 35129, Padua, Italy.,Department of Biology, University of Padua, 35121, Padua, Italy.,Max Planck Institute of Immunology and Epigenetics, 79108, Freiburg im Breisgau, Germany
| | - Andrea Urbani
- Department of Biomedical Sciences, University of Padua, Padua, 35121, Italy
| | - Anna Pellattiero
- Venetian Institute of Molecular Medicine, 35129, Padua, Italy.,Department of Biology, University of Padua, 35121, Padua, Italy
| | - Enrique Calvo
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, 28029, Madrid, Spain
| | - Jesús Vázquez
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, 28029, Madrid, Spain
| | - José Antonio Enríquez
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, 28029, Madrid, Spain.,CIBERFES, Institute of Health Carlos III, Madrid, Spain
| | - Christoph Gerle
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan.,Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Japan
| | | | - Paolo Bernardi
- Department of Biomedical Sciences, University of Padua, Padua, 35121, Italy.,Institute of Neuroscience, Consiglio Nazionale delle Ricerche, Padua, Italy
| | - Luca Scorrano
- Venetian Institute of Molecular Medicine, 35129, Padua, Italy. .,Department of Biology, University of Padua, 35121, Padua, Italy.
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119
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Arguello T, Köhrer C, RajBhandary UL, Moraes CT. Mitochondrial methionyl N-formylation affects steady-state levels of oxidative phosphorylation complexes and their organization into supercomplexes. J Biol Chem 2018; 293:15021-15032. [PMID: 30087118 DOI: 10.1074/jbc.ra118.003838] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 08/02/2018] [Indexed: 12/20/2022] Open
Abstract
N-Formylation of the Met-tRNAMet by the nuclearly encoded mitochondrial methionyl-tRNA formyltransferase (MTFMT) has been found to be a key determinant of protein synthesis initiation in mitochondria. In humans, mutations in the MTFMT gene result in Leigh syndrome, a progressive and severe neurometabolic disorder. However, the absolute requirement of formylation of Met-tRNAMet for protein synthesis in mammalian mitochondria is still debated. Here, we generated a Mtfmt-KO mouse fibroblast cell line and demonstrated that N-formylation of the first methionine via fMet-tRNAMet by MTFMT is not an absolute requirement for initiation of protein synthesis. However, it differentially affected the efficiency of synthesis of mtDNA-coded polypeptides. Lack of methionine N-formylation did not compromise the stability of these individual subunits but had a marked effect on the assembly and stability of the OXPHOS complexes I and IV and on their supercomplexes. In summary, N-formylation is not essential for mitochondrial protein synthesis but is critical for efficient synthesis of several mitochondrially encoded peptides and for OXPHOS complex stability and assembly into supercomplexes.
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Affiliation(s)
- Tania Arguello
- From the Department of Neurology, University of Miami School of Medicine, Miami, Florida 33136 and
| | - Caroline Köhrer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Uttam L RajBhandary
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Carlos T Moraes
- From the Department of Neurology, University of Miami School of Medicine, Miami, Florida 33136 and
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120
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Qu C, Zhang S, Wang W, Li M, Wang Y, van der Heijde-Mulder M, Shokrollahi E, Hakim MS, Raat NJH, Peppelenbosch MP, Pan Q. Mitochondrial electron transport chain complex III sustains hepatitis E virus replication and represents an antiviral target. FASEB J 2018; 33:1008-1019. [PMID: 30070932 DOI: 10.1096/fj.201800620r] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hepatitis E virus (HEV) infection has emerged as a global health problem. However, no approved medication is available, and the infection biology remains largely elusive. Electron transport chain (ETC), a key component of the mitochondria, is the main site that produces ATP and reactive oxygen species (ROS). By profiling the role of the different complexes of the mitochondrial ETC, we found that pharmacological inhibition of complex III, a well-defined drug target for the treatment of malaria and Pneumocystis pneumonia, potently restricts HEV replication. This effect demonstrated in our HEV models is equivalent to the anti-HEV potency of ribavirin, a widely used off-label treatment for patients with chronic HEV. Mechanistically, we found that this effect is independent of ATP production, ROS level, and pyridine depletion. By using pharmacological inhibitors and genetic approaches, we found that mitochondrial permeability transition pore (MPTP), a newly identified component of ETC, provides basal defense against HEV infection. HEV interferes with the opening of the MPTP. Furthermore, inhibition of the MPTP attenuated the anti-HEV effect of complex III inhibitors, suggesting that the MPTP mediates the antiviral effects of these inhibitors. These findings reveal new insights on HEV-host interactions and provide viable anti-HEV targets for therapeutic development.-Qu, C., Zhang, S., Wang, W., Li, M., Wang, Y., van der Heijde-Mulder, M., Shokrollahi, E., Hakim, M. S., Raat, N. J. H., Peppelenbosch, M. P., Pan, Q. Mitochondrial electron transport chain complex III sustains hepatitis E virus replication and represents an antiviral target.
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Affiliation(s)
- Changbo Qu
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands
| | - Shaoshi Zhang
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands
| | - Wenshi Wang
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands
| | - Meng Li
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands
| | - Yijin Wang
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands.,Department of Pathology and Hepatology, Beijing 302 Hospital, Beijing, China
| | | | - Ehsan Shokrollahi
- Department of Anesthesiology, Laboratory of Experimental Anesthesiology, The Erasmus University Medical Center (Erasmus MC), Rotterdam, The Netherlands; and
| | - Mohamad S Hakim
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands.,Department of Microbiology, Faculty of Medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Nicolaas J H Raat
- Department of Anesthesiology, Laboratory of Experimental Anesthesiology, The Erasmus University Medical Center (Erasmus MC), Rotterdam, The Netherlands; and
| | - Maikel P Peppelenbosch
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands
| | - Qiuwei Pan
- Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands
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121
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Zong S, Wu M, Gu J, Liu T, Guo R, Yang M. Structure of the intact 14-subunit human cytochrome c oxidase. Cell Res 2018; 28:1026-1034. [PMID: 30030519 DOI: 10.1038/s41422-018-0071-1] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 06/23/2018] [Accepted: 07/03/2018] [Indexed: 01/14/2023] Open
Abstract
Respiration is one of the most basic features of living organisms, and the electron transport chain complexes are probably the most complicated protein system in mitochondria. Complex-IV is the terminal enzyme of the electron transport chain, existing either as randomly scattered complexes or as a component of supercomplexes. NDUFA4 was previously assumed as a subunit of complex-I, but recent biochemical data suggested it may be a subunit of complex-IV. However, no structural evidence supporting this notion was available till now. Here we obtained the 3.3 Å resolution structure of complex-IV derived from the human supercomplex I1III2IV1 and assigned the NDUFA4 subunit into complex-IV. Intriguingly, NDUFA4 lies exactly at the dimeric interface observed in previously reported crystal structures of complex-IV homodimer which would preclude complex-IV dimerization. Combining previous structural and biochemical data shown by us and other groups, we propose that the intact complex-IV is a monomer containing 14 subunits.
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Affiliation(s)
- Shuai Zong
- Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Meng Wu
- Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jinke Gu
- Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Tianya Liu
- Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Runyu Guo
- Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Maojun Yang
- Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China. .,School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, China.
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122
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Benmoussa K, Garaude J, Acín-Pérez R. How Mitochondrial Metabolism Contributes to Macrophage Phenotype and Functions. J Mol Biol 2018; 430:3906-3921. [PMID: 30006265 DOI: 10.1016/j.jmb.2018.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 07/02/2018] [Accepted: 07/03/2018] [Indexed: 01/02/2023]
Abstract
Metabolic reprogramming of cells from the innate immune system is one of the most noteworthy topics in immunological research nowadays. Upon infection or tissue damage, innate immune cells, such as macrophages, mobilize various immune and metabolic signals to mount a response best suited to eradicate the threat. Current data indicate that both the immune and metabolic responses are closely interconnected. On account of its peculiar position in regulating both of these processes, the mitochondrion has emerged as a critical organelle that orchestrates the coordinated metabolic and immune adaptations in macrophages. Significant effort is now underway to understand how metabolic features of differentiated macrophages regulate their immune specificities with the eventual goal to manipulate cellular metabolism to control immunity. In this review, we highlight some of the recent work that place cellular and mitochondrial metabolism in a central position in the macrophage differentiation program.
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Affiliation(s)
- Khaddouj Benmoussa
- Laboratoire Maladies Rares, Génétique et Métabolisme, INSERM U1211, Université de Bordeaux, CHU Pellegrin, École de Sages-Femmes, 33000 Bordeaux, France
| | - Johan Garaude
- Laboratoire Maladies Rares, Génétique et Métabolisme, INSERM U1211, Université de Bordeaux, CHU Pellegrin, École de Sages-Femmes, 33000 Bordeaux, France.
| | - Rebeca Acín-Pérez
- UCLA Division of Endocrinology, Diabetes and Metabolism, David Geffen School of Medicine, 10833 Le Conte Avenue, CHS 27-200, Los Angeles, CA 90025, USA; Centro Nacional de Investigaciones Cardiovasculares Carlos III, Melchor Fernandez de Almagro 3, 28029 Madrid, Spain.
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123
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Novel Homozygous Variant in TTC19 Causing Mitochondrial Complex III Deficiency with Recurrent Stroke-Like Episodes: Expanding the Phenotype. Semin Pediatr Neurol 2018; 26:16-20. [PMID: 29961508 DOI: 10.1016/j.spen.2018.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A 7-year-old boy with family history of consanguinity presented with developmental delay and recurrent hemiplegia involving both sides of the body, with variable facial and ocular involvement. Brain MRI showed bilateral striatal necrosis with cystic degeneration and lactate peaks on spectroscopy. Biochemical testing demonstrated mildly elevated lactate and pyruvate. Whole-exome sequencing revealed a novel homozygous pathogenic frameshift mutation in gene TTC19, diagnostic of mitochondrial complex III deficiency.
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124
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The mitochondrial respiratory chain: A metabolic rheostat of innate immune cell-mediated antibacterial responses. Mitochondrion 2018; 41:28-36. [DOI: 10.1016/j.mito.2017.10.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 10/11/2017] [Accepted: 10/11/2017] [Indexed: 01/23/2023]
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125
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The Organization of Mitochondrial Supercomplexes is Modulated by Oxidative Stress In Vivo in Mouse Models of Mitochondrial Encephalopathy. Int J Mol Sci 2018; 19:ijms19061582. [PMID: 29861458 PMCID: PMC6032222 DOI: 10.3390/ijms19061582] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/16/2018] [Accepted: 05/22/2018] [Indexed: 12/11/2022] Open
Abstract
We examine the effect of oxidative stress on the stability of mitochondrial respiratory complexes and their association into supercomplexes (SCs) in the neuron-specific Rieske iron sulfur protein (RISP) and COX10 knockout (KO) mice. Previously we reported that these two models display different grades of oxidative stress in distinct brain regions. Using blue native gel electrophoresis, we observed a redistribution of the architecture of SCs in KO mice. Brain regions with moderate levels of oxidative stress (cingulate cortex of both COX10 and RISP KO and hippocampus of the RISP KO) showed a significant increase in the levels of high molecular weight (HMW) SCs. High levels of oxidative stress in the piriform cortex of the RISP KO negatively impacted the stability of CI, CIII and SCs. Treatment of the RISP KO with the mitochondrial targeted antioxidant mitoTEMPO preserved the stability of respiratory complexes and formation of SCs in the piriform cortex and increased the levels of glutathione peroxidase. These results suggest that mild to moderate levels of oxidative stress can modulate SCs into a more favorable architecture of HMW SCs to cope with rising levels of free radicals and cover the energetic needs.
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126
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Formosa LE, Dibley MG, Stroud DA, Ryan MT. Building a complex complex: Assembly of mitochondrial respiratory chain complex I. Semin Cell Dev Biol 2018; 76:154-162. [DOI: 10.1016/j.semcdb.2017.08.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 07/26/2017] [Accepted: 08/04/2017] [Indexed: 10/19/2022]
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127
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Lobo-Jarne T, Ugalde C. Respiratory chain supercomplexes: Structures, function and biogenesis. Semin Cell Dev Biol 2018; 76:179-190. [PMID: 28743641 PMCID: PMC5780262 DOI: 10.1016/j.semcdb.2017.07.021] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 01/08/2023]
Abstract
Over the past sixty years, researchers have made outmost efforts to clarify the structural organization and functional regulation of the complexes that configure the mitochondrial respiratory chain. As a result, the entire composition of each individual complex is practically known and, aided by notable structural advances in mammals, it is now widely accepted that these complexes stablish interactions to form higher-order supramolecular structures called supercomplexes and respirasomes. The mechanistic models and players that regulate the function and biogenesis of such superstructures are still under intense debate, and represent one of the hottest topics of the mitochondrial research field at present. Noteworthy, understanding the pathways involved in the assembly and organization of respiratory chain complexes and supercomplexes is of high biomedical relevance because molecular alterations in these pathways frequently result in severe mitochondrial disorders. The purpose of this review is to update the structural, biogenetic and functional knowledge about the respiratory chain supercomplexes and assembly factors involved in their formation, with special emphasis on their implications in mitochondrial disease. Thanks to the integrated data resulting from recent structural, biochemical and genetic approaches in diverse biological systems, the regulation of the respiratory chain function arises at multiple levels of complexity.
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Affiliation(s)
- Teresa Lobo-Jarne
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid 28041, Spain
| | - Cristina Ugalde
- Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid 28041, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), U723, Madrid 28029, Spain.
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128
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Kretzschmar C, Roolf C, Timmer K, Sekora A, Knübel G, Murua Escobar H, Fuellen G, Ibrahim SM, Tiedge M, Baltrusch S, Jaster R, Köhling R, Junghanss C. Polymorphisms of the murine mitochondrial ND4, CYTB and COX3 genes impact hematopoiesis during aging. Oncotarget 2018; 7:74460-74472. [PMID: 27626489 PMCID: PMC5342679 DOI: 10.18632/oncotarget.11952] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 09/02/2016] [Indexed: 12/16/2022] Open
Abstract
During aging, mitochondrial DNA (mtDNA) can accumulate mutations leading to increasing levels of reactive oxygen species (ROS). Increased ROS were described to activate formerly quiescent hematopoietic stem cells (HSC). Mutations in mtDNA were shown to enhance the risk for myelodysplastic syndrome and leukemia. However, the complex relationship between mtDNA variations, ROS and aging of the hematopoietic system is not fully understood. Herein, three mouse strains with mtDNA polymorphisms in genes of respiratory chain complexes I (ND4), III (CYTB) and IV (COX3) were compared to a reference strain during aging. Analysis focused on ROS and ATP levels, bone marrow composition and blood counts. Additionally, hematopoietic restoration capacity following cytotoxic stress was tested. Mice with polymorphisms in ND4 and CYTB gene had significantly decreasing ROS levels in bone marrow cells during aging, without effecting ATP levels. In addition, the frequency of stem and progenitor cells increased during aging but the amount of lymphocytes in the peripheral blood decreased during aging. In summary, the presence of mtDNA polymorphisms affecting the respiratory chain complexes I, III and IV was associated with altered ROS levels as well as changes in BM and peripheral blood composition during aging.
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Affiliation(s)
- Christin Kretzschmar
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
| | - Catrin Roolf
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
| | - Katrin Timmer
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
| | - Anett Sekora
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
| | - Gudrun Knübel
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
| | - Hugo Murua Escobar
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
| | - Georg Fuellen
- Institute for Biostatistics and Informatics in Medicine and Ageing Research, Rostock University Medical Center, Rostock, Germany
| | - Saleh M Ibrahim
- Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
| | - Markus Tiedge
- Institute of Medical Biochemistry and Molecular Biology, Rostock University Medical Center, Rostock, Germany
| | - Simone Baltrusch
- Institute of Medical Biochemistry and Molecular Biology, Rostock University Medical Center, Rostock, Germany
| | - Robert Jaster
- Department of Medicine II, Division of Gastroenterology, Rostock University Medical Center, Rostock, Germany
| | - Rüdiger Köhling
- Oscar Langendorff Institute of Physiology, Rostock University Medical Center, Rostock, Germany
| | - Christian Junghanss
- Department of Medicine III - Hematology/Oncology/Palliative Care, Rostock University Medical Center, Rostock, Germany
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129
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Abstract
Mitochondria are the power stations of the eukaryotic cell, using the energy released by the oxidation of glucose and other sugars to produce ATP. Electrons are transferred from NADH, produced in the citric acid cycle in the mitochondrial matrix, to oxygen by a series of large protein complexes in the inner mitochondrial membrane, which create a transmembrane electrochemical gradient by pumping protons across the membrane. The flow of protons back into the matrix via a proton channel in the ATP synthase leads to conformational changes in the nucleotide binding pockets and the formation of ATP. The three proton pumping complexes of the electron transfer chain are NADH-ubiquinone oxidoreductase or complex I, ubiquinone-cytochrome c oxidoreductase or complex III, and cytochrome c oxidase or complex IV. Succinate dehydrogenase or complex II does not pump protons, but contributes reduced ubiquinone. The structures of complex II, III and IV were determined by x-ray crystallography several decades ago, but complex I and ATP synthase have only recently started to reveal their secrets by advances in x-ray crystallography and cryo-electron microscopy. The complexes I, III and IV occur to a certain extent as supercomplexes in the membrane, the so-called respirasomes. Several hypotheses exist about their function. Recent cryo-electron microscopy structures show the architecture of the respirasome with near-atomic detail. ATP synthase occurs as dimers in the inner mitochondrial membrane, which by their curvature are responsible for the folding of the membrane into cristae and thus for the huge increase in available surface that makes mitochondria the efficient energy plants of the eukaryotic cell.
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Affiliation(s)
- Joana S Sousa
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Edoardo D'Imprima
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Janet Vonck
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
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130
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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.
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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
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131
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A unique respiratory adaptation in Drosophila independent of supercomplex formation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1859:154-163. [PMID: 29191512 DOI: 10.1016/j.bbabio.2017.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/13/2017] [Accepted: 11/23/2017] [Indexed: 01/06/2023]
Abstract
Large assemblies of respiratory chain complexes, known as supercomplexes, are present in the mitochondrial membrane in mammals and yeast, as well as in some bacterial membranes. The formation of supercomplexes is thought to contribute to efficient electron transfer, stabilization of each enzyme complex, and inhibition of reactive oxygen species (ROS) generation. In this study, mitochondria from various organisms were solubilized with digitonin, and then the solubilized complexes were separated by blue native PAGE (BN-PAGE). The results revealed a supercomplex consisting of complexes I, III, and IV in mitochondria from bovine and porcine heart, and a supercomplex consisting primarily of complexes I and III in mitochondria from mouse heart and liver. However, supercomplexes were barely detectable in Drosophila flight-muscle mitochondria, and only dimeric complex V was present. Drosophila mitochondria exhibited the highest rates of oxygen consumption and NADH oxidation, and the concentrations of the electron carriers, cytochrome c and quinone were higher than in other species. Respiratory chain complexes were tightly packed in the mitochondrial membrane containing abundant phosphatidylethanolamine with the fatty acid palmitoleic acid (C16:1), which is relatively high oxidation-resistant as compared to poly-unsaturated fatty acid. These properties presumably allow efficient electron transfer in Drosophila. These findings reveal the existence of a new mechanism of biological adaptation independent of supercomplex formation.
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132
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Oxidative Stress: Mechanistic Insights into Inherited Mitochondrial Disorders and Parkinson's Disease. J Clin Med 2017; 6:jcm6110100. [PMID: 29077060 PMCID: PMC5704117 DOI: 10.3390/jcm6110100] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 10/20/2017] [Accepted: 10/23/2017] [Indexed: 12/21/2022] Open
Abstract
Oxidative stress arises when cellular antioxidant defences become overwhelmed by a surplus generation of reactive oxygen species (ROS). Once this occurs, many cellular biomolecules such as DNA, lipids, and proteins become susceptible to free radical-induced oxidative damage, and this may consequently lead to cellular and ultimately tissue and organ dysfunction. Mitochondria, as well as being a source of ROS, are vulnerable to oxidative stress-induced damage with a number of key biomolecules being the target of oxidative damage by free radicals, including membrane phospholipids, respiratory chain complexes, proteins, and mitochondrial DNA (mt DNA). As a result, a deficit in cellular energy status may occur along with increased electron leakage and partial reduction of oxygen. This in turn may lead to a further increase in ROS production. Oxidative damage to certain mitochondrial biomolecules has been associated with, and implicated in the pathophysiology of a number of diseases. It is the purpose of this review to discuss the impact of such oxidative stress and subsequent damage by reviewing our current knowledge of the pathophysiology of several inherited mitochondrial disorders together with our understanding of perturbations observed in the more commonly acquired neurodegenerative disorders such as Parkinson’s disease (PD). Furthermore, the potential use and feasibility of antioxidant therapies as an adjunct to lower the accumulation of damaging oxidative species and hence slow disease progression will also be discussed.
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133
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Letts JA, Sazanov LA. Clarifying the supercomplex: the higher-order organization of the mitochondrial electron transport chain. Nat Struct Mol Biol 2017; 24:800-808. [PMID: 28981073 DOI: 10.1038/nsmb.3460] [Citation(s) in RCA: 220] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 08/03/2017] [Indexed: 12/27/2022]
Abstract
The oxidative phosphorylation electron transport chain (OXPHOS-ETC) of the inner mitochondrial membrane is composed of five large protein complexes, named CI-CV. These complexes convert energy from the food we eat into ATP, a small molecule used to power a multitude of essential reactions throughout the cell. OXPHOS-ETC complexes are organized into supercomplexes (SCs) of defined stoichiometry: CI forms a supercomplex with CIII2 and CIV (SC I+III2+IV, known as the respirasome), as well as with CIII2 alone (SC I+III2). CIII2 forms a supercomplex with CIV (SC III2+IV) and CV forms dimers (CV2). Recent cryo-EM studies have revealed the structures of SC I+III2+IV and SC I+III2. Furthermore, recent work has shed light on the assembly and function of the SCs. Here we review and compare these recent studies and discuss how they have advanced our understanding of mitochondrial electron transport.
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Affiliation(s)
- James A Letts
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Leonid A Sazanov
- Institute of Science and Technology Austria, Klosterneuburg, Austria
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134
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Targeting mitochondrial translation by inhibiting DDX3: a novel radiosensitization strategy for cancer treatment. Oncogene 2017; 37:63-74. [PMID: 28869602 PMCID: PMC5756132 DOI: 10.1038/onc.2017.308] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 06/16/2017] [Accepted: 07/13/2017] [Indexed: 12/14/2022]
Abstract
DDX3 is a DEAD box RNA helicase with oncogenic properties. RK-33 is developed as a small molecule inhibitor of DDX3 and showed potent radiosensitizing activity in preclinical tumor models. This study aimed to assess DDX3 as a target in breast cancer and to elucidate how RK-33 exerts its anti-neoplastic effects. High DDX3 expression was present in 35% of breast cancer patient samples and correlated with markers of aggressiveness and shorter survival. With a quantitative proteomics approach, we identified proteins involved in the mitochondrial translation and respiratory electron transport pathways to be significantly downregulated after RK-33 or DDX3 knockdown. DDX3 localized to the mitochondria and DDX3 inhibition with RK-33 reduced mitochondrial translation. As a consequence, oxygen consumption rates and intracellular ATP concentrations decreased and reactive oxygen species (ROS) increased. RK-33 antagonized the increase in oxygen consumption and ATP production observed after exposure to ionizing radiation and reduced DNA repair. Overall, we conclude that DDX3 inhibition with RK-33 causes radiosensitization in breast cancer through inhibition of mitochondrial translation, which results in reduced oxidative phosphorylation capacity and increased ROS levels, culminating in a bioenergetic catastrophe.
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135
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Jang S, Javadov S. Association between ROS production, swelling and the respirasome integrity in cardiac mitochondria. Arch Biochem Biophys 2017; 630:1-8. [PMID: 28736227 DOI: 10.1016/j.abb.2017.07.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/05/2017] [Accepted: 07/17/2017] [Indexed: 02/04/2023]
Abstract
Although mitochondrial Ca2+ overload and ROS production play a critical role in mitochondria-mediated cell death, a cause-effect relationship between them remains elusive. This study elucidated the crosstalk between mitochondrial swelling, ROS production, and electron transfer chain (ETC) supercomplexes in rat heart mitochondria in response to Ca2+ and tert-butyl hydroperoxide (TBH), a lipid-soluble organic peroxide. Results showed that ROS production induced by TBH was significantly increased in the presence of Ca2+ in a dose-dependent manner. TBH markedly inhibited the state 3 respiration rate with no effect on the mitochondrial swelling. Ca2+ exerted a slight effect on mitochondrial respiration that was greatly aggravated by TBH. Analysis of supercomplexes revealed a minor difference in the presence of TBH and/or Ca2+. However, incubation of mitochondria in the presence of high Ca2+ (1 mM) or inhibitors of ETC complexes (rotenone and antimycin A) induced disintegration of the main supercomplex, respirasome. Thus, PTP-dependent swelling of mitochondria solely depends on Ca2+ but not ROS. TBH has no effect on the respirasome while Ca2+ induces disintegration of the supercomplex only at a high concentration. Intactness of individual ETC complexes I and III is important for maintenance of the structural integrity of the respirasome.
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Affiliation(s)
- Sehwan Jang
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
| | - Sabzali Javadov
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico.
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136
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Combined Respiratory Chain Deficiency and UQCC2 Mutations in Neonatal Encephalomyopathy: Defective Supercomplex Assembly in Complex III Deficiencies. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:7202589. [PMID: 28804536 PMCID: PMC5540226 DOI: 10.1155/2017/7202589] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/22/2017] [Accepted: 06/04/2017] [Indexed: 11/17/2022]
Abstract
Vertebrate respiratory chain complex III consists of eleven subunits. Mutations in five subunits either mitochondrial (MT-CYB) or nuclear (CYC1, UQCRC2, UQCRB, and UQCRQ) encoded have been reported. Defects in five further factors for assembly (TTC19, UQCC2, and UQCC3) or iron-sulphur cluster loading (BCS1L and LYRM7) cause complex III deficiency. Here, we report a second patient with UQCC2 deficiency. This girl was born prematurely; pregnancy was complicated by intrauterine growth retardation and oligohydramnios. She presented with respiratory distress syndrome, developed epileptic seizures progressing to status epilepticus, and died at day 33. She had profound lactic acidosis and elevated urinary pyruvate. Exome sequencing revealed two homozygous missense variants in UQCC2, leading to a severe reduction of UQCC2 protein. Deficiency of complexes I and III was found enzymatically and on the protein level. A review of the literature on genetically distinct complex III defects revealed that, except TTC19 deficiency, the biochemical pattern was very often a combined respiratory chain deficiency. Besides complex III, typically, complex I was decreased, in some cases complex IV. In accordance with previous observations, the presence of assembled complex III is required for the stability or assembly of complexes I and IV, which might be related to respirasome/supercomplex formation.
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137
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Xia JH, Li HL, Zhang Y, Meng ZN, Lin HR. Identifying selectively important amino acid positions associated with alternative habitat environments in fish mitochondrial genomes. Mitochondrial DNA A DNA Mapp Seq Anal 2017; 29:511-524. [PMID: 28423967 DOI: 10.1080/24701394.2017.1315567] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Fish species inhabitating seawater (SW) or freshwater (FW) habitats have to develop genetic adaptations to alternative environment factors, especially salinity. Functional consequences of the protein variations associated with habitat environments in fish mitochondrial genomes have not yet received much attention. We analyzed 829 complete fish mitochondrial genomes and compared the amino acid differences of 13 mitochondrial protein families between FW and SW fish groups. We identified 47 specificity determining sites (SDS) that associated with FW or SW environments from 12 mitochondrial protein families. Thirty-two (68%) of the SDS sites are hydrophobic, 13 (28%) are neutral, and the remaining sites are acidic or basic. Seven of those SDS from ND1, ND2 and ND5 were scored as probably damaging to the protein structures. Furthermore, phylogenetic tree based Bayes Empirical Bayes analysis also detected 63 positive sites associated with alternative habitat environments across ten mtDNA proteins. These signatures could be important for studying mitochondrial genetic variation relevant to fish physiology and ecology.
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Affiliation(s)
- Jun Hong Xia
- a State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University , Guangzhou , PR China.,b Guangdong Provincial Key Laboratory for Aquatic Economic Animals, College of Life Sciences, Sun Yat-Sen University , Guangzhou , PR China
| | - Hong Lian Li
- a State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University , Guangzhou , PR China.,b Guangdong Provincial Key Laboratory for Aquatic Economic Animals, College of Life Sciences, Sun Yat-Sen University , Guangzhou , PR China
| | - Yong Zhang
- a State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University , Guangzhou , PR China.,b Guangdong Provincial Key Laboratory for Aquatic Economic Animals, College of Life Sciences, Sun Yat-Sen University , Guangzhou , PR China
| | - Zi Ning Meng
- a State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University , Guangzhou , PR China.,b Guangdong Provincial Key Laboratory for Aquatic Economic Animals, College of Life Sciences, Sun Yat-Sen University , Guangzhou , PR China
| | - Hao Ran Lin
- a State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University , Guangzhou , PR China.,b Guangdong Provincial Key Laboratory for Aquatic Economic Animals, College of Life Sciences, Sun Yat-Sen University , Guangzhou , PR China
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138
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Lopez-Fabuel I, Martin-Martin L, Resch-Beusher M, Azkona G, Sanchez-Pernaute R, Bolaños JP. Mitochondrial respiratory chain disorganization in Parkinson's disease-relevant PINK1 and DJ1 mutants. Neurochem Int 2017; 109:101-105. [PMID: 28408307 DOI: 10.1016/j.neuint.2017.03.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/21/2017] [Accepted: 03/24/2017] [Indexed: 12/21/2022]
Abstract
Brain mitochondrial complex I (CI) damage is associated with the loss of the dopaminergic neurons of the Substantia Nigra in Parkinson's Disease (PD) patients. However, whether CI inhibition is associated with any alteration of the mitochondrial respiratory chain (MRC) organization in PD patients is unknown. To address this issue, here we analyzed the MRC by blue native gel electrophoresis (BNGE) followed by western blotting, in mitochondria purified from fibroblasts of patients harboring PD-relevant Pink1 mutations. We found a decrease in free CI, and in free versus supercomplexes (SCs)-assembled CI in PD; however, free complex III (CIII) was only modestly affected, whereas its free versus SCs-assembled forms decreased. Interestingly, complex IV (CIV) was considerably lost in the PD samples. These results were largely confirmed in mitochondria isolated from cultured neurons from Pink1-/- mice, and in cultured neurons and forebrain samples from the PD-related Dj1-/- mice. Thus, besides CI damage, the MRC undergoes a profound structural remodeling in PD likely responsible for the energetic inefficiency and mitochondrial reactive oxygen species (mROS) over-production observed in this disease.
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Affiliation(s)
- Irene Lopez-Fabuel
- University of Salamanca, CIBERFES, Institute of Functional Biology and Genomics (IBFG), CSIC, 37007 Salamanca, Spain; Institute of Biomedical Research of Salamanca (IBSAL), University Hospital of Salamanca, 37007 Salamanca, Spain
| | - Lucia Martin-Martin
- University of Salamanca, CIBERFES, Institute of Functional Biology and Genomics (IBFG), CSIC, 37007 Salamanca, Spain; Institute of Biomedical Research of Salamanca (IBSAL), University Hospital of Salamanca, 37007 Salamanca, Spain
| | - Monica Resch-Beusher
- University of Salamanca, CIBERFES, Institute of Functional Biology and Genomics (IBFG), CSIC, 37007 Salamanca, Spain; Institute of Biomedical Research of Salamanca (IBSAL), University Hospital of Salamanca, 37007 Salamanca, Spain
| | - Garikoitz Azkona
- Animal Research Facility, Scientific and Technological Centers, University of Barcelona, 08007 Barcelona, Spain
| | | | - Juan P Bolaños
- University of Salamanca, CIBERFES, Institute of Functional Biology and Genomics (IBFG), CSIC, 37007 Salamanca, Spain; Institute of Biomedical Research of Salamanca (IBSAL), University Hospital of Salamanca, 37007 Salamanca, Spain.
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139
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Rieger B, Shalaeva DN, Söhnel AC, Kohl W, Duwe P, Mulkidjanian AY, Busch KB. Lifetime imaging of GFP at CoxVIIIa reports respiratory supercomplex assembly in live cells. Sci Rep 2017; 7:46055. [PMID: 28383048 PMCID: PMC5382582 DOI: 10.1038/srep46055] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 03/10/2017] [Indexed: 02/02/2023] Open
Abstract
The assembly of respiratory complexes into macromolecular supercomplexes is currently a hot topic, especially in the context of newly available structural details. However, most work to date has been done with purified detergent-solubilized material and in situ confirmation is absent. We here set out to enable the recording of respiratory supercomplex formation in living cells. Fluorescent sensor proteins were placed at specific positions at cytochrome c oxidase suspected to either be at the surface of a CI1CIII2CIV1 supercomplex or buried within this supercomplex. In contrast to other loci, sensors at subunits CoxVIIIa and CoxVIIc reported a dense protein environment, as detected by significantly shortened fluorescence lifetimes. According to 3D modelling CoxVIIIa and CoxVIIc are buried in the CI1CIII2CIV1 supercomplex. Suppression of supercomplex scaffold proteins HIGD2A and CoxVIIa2l was accompanied by an increase in the lifetime of the CoxVIIIa-sensor in line with release of CIV from supercomplexes. Strikingly, our data provide strong evidence for defined stable supercomplex configuration in situ.
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Affiliation(s)
- Bettina Rieger
- Institute of Molecular Cell Biology, School of Biology, University of Münster, D-48149 Münster, Germany.,Mitochondrial Dynamics Group, School of Biology, University of Osnabrueck, D-49076 Osnabrueck, Germany
| | - Daria N Shalaeva
- School of Physics, University of Osnabrueck, D-49069 Osnabrueck, Germany
| | - Anna-Carina Söhnel
- Institute of Molecular Cell Biology, School of Biology, University of Münster, D-48149 Münster, Germany.,Mitochondrial Dynamics Group, School of Biology, University of Osnabrueck, D-49076 Osnabrueck, Germany
| | - Wladislaw Kohl
- Mitochondrial Dynamics Group, School of Biology, University of Osnabrueck, D-49076 Osnabrueck, Germany
| | - Patrick Duwe
- Institute of Molecular Cell Biology, School of Biology, University of Münster, D-48149 Münster, Germany
| | - Armen Y Mulkidjanian
- School of Physics, University of Osnabrueck, D-49069 Osnabrueck, Germany.,School of Bioengineering and Bioinformatics, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia.,A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
| | - Karin B Busch
- Institute of Molecular Cell Biology, School of Biology, University of Münster, D-48149 Münster, Germany.,Mitochondrial Dynamics Group, School of Biology, University of Osnabrueck, D-49076 Osnabrueck, Germany
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140
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Abstract
Respiratory chain dysfunction plays an important role in human disease and aging. It is now well established that the individual respiratory complexes can be organized into supercomplexes, and structures for these macromolecular assemblies, determined by electron cryo-microscopy, have been described recently. Nevertheless, the reason why supercomplexes exist remains an enigma. The widely held view that they enhance catalysis by channeling substrates is challenged by both structural and biophysical information. Here, we evaluate and discuss data and hypotheses on the structures, roles, and assembly of respiratory-chain supercomplexes and propose a future research agenda to address unanswered questions.
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Affiliation(s)
- Dusanka Milenkovic
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany
| | - James N Blaza
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK
| | - Nils-Göran Larsson
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, 50931 Cologne, Germany; Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden.
| | - Judy Hirst
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK.
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141
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Morris G, Walder K, McGee SL, Dean OM, Tye SJ, Maes M, Berk M. A model of the mitochondrial basis of bipolar disorder. Neurosci Biobehav Rev 2017; 74:1-20. [DOI: 10.1016/j.neubiorev.2017.01.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 01/08/2017] [Accepted: 01/10/2017] [Indexed: 12/11/2022]
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142
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Greggio C, Jha P, Kulkarni SS, Lagarrigue S, Broskey NT, Boutant M, Wang X, Conde Alonso S, Ofori E, Auwerx J, Cantó C, Amati F. Enhanced Respiratory Chain Supercomplex Formation in Response to Exercise in Human Skeletal Muscle. Cell Metab 2017; 25:301-311. [PMID: 27916530 DOI: 10.1016/j.cmet.2016.11.004] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 09/08/2016] [Accepted: 11/05/2016] [Indexed: 12/19/2022]
Abstract
Mitochondrial dysfunction is a hallmark of multiple metabolic complications. Physical activity is known to increase mitochondrial content in skeletal muscle, counteracting age-related decline in muscle function and protecting against metabolic and cardiovascular complications. Here, we investigated the effect of 4 months of exercise training on skeletal muscle mitochondria electron transport chain complexes and supercomplexes in 26 healthy, sedentary older adults. Exercise differentially modulated respiratory complexes. Complex I was the most upregulated complex and not stoichiometrically associated to the other complexes. In contrast to the other complexes, complex I was almost exclusively found assembled in supercomplexes in muscle mitochondria. Overall, supercomplex content was increased after exercise. In particular, complexes I, III, and IV were redistributed to supercomplexes in the form of I+III2+IV. Taken together, our results provide the first evidence that exercise affects the stoichiometry of supercomplex formation in humans and thus reveal a novel adaptive mechanism for increased energy demand.
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Affiliation(s)
- Chiara Greggio
- Aging and Muscle Metabolism Laboratory, Department of Physiology, University of Lausanne, Lausanne 1005, Switzerland
| | - Pooja Jha
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland
| | | | - Sylviane Lagarrigue
- Aging and Muscle Metabolism Laboratory, Department of Physiology, University of Lausanne, Lausanne 1005, Switzerland
| | - Nicholas T Broskey
- Aging and Muscle Metabolism Laboratory, Department of Physiology, University of Lausanne, Lausanne 1005, Switzerland
| | - Marie Boutant
- Nestlé Institute of Health Sciences, Lausanne 1015, Switzerland
| | - Xu Wang
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland
| | - Sonia Conde Alonso
- Aging and Muscle Metabolism Laboratory, Department of Physiology, University of Lausanne, Lausanne 1005, Switzerland; Institute of Sports Sciences, University of Lausanne, Lausanne 1005, Switzerland
| | - Emmanuel Ofori
- Aging and Muscle Metabolism Laboratory, Department of Physiology, University of Lausanne, Lausanne 1005, Switzerland
| | - Johan Auwerx
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland.
| | - Carles Cantó
- Nestlé Institute of Health Sciences, Lausanne 1015, Switzerland.
| | - Francesca Amati
- Aging and Muscle Metabolism Laboratory, Department of Physiology, University of Lausanne, Lausanne 1005, Switzerland; Institute of Sports Sciences, University of Lausanne, Lausanne 1005, Switzerland; Service of Endocrinology, Diabetology, and Metabolism, Department of Medicine, Lausanne University Hospital, Lausanne 1011, Switzerland.
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143
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Hardie RA, van Dam E, Cowley M, Han TL, Balaban S, Pajic M, Pinese M, Iconomou M, Shearer RF, McKenna J, Miller D, Waddell N, Pearson JV, Grimmond SM, Sazanov L, Biankin AV, Villas-Boas S, Hoy AJ, Turner N, Saunders DN. Mitochondrial mutations and metabolic adaptation in pancreatic cancer. Cancer Metab 2017; 5:2. [PMID: 28163917 PMCID: PMC5282905 DOI: 10.1186/s40170-017-0164-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/18/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Pancreatic cancer has a five-year survival rate of ~8%, with characteristic molecular heterogeneity and restricted treatment options. Targeting metabolism has emerged as a potentially effective therapeutic strategy for cancers such as pancreatic cancer, which are driven by genetic alterations that are not tractable drug targets. Although somatic mitochondrial genome (mtDNA) mutations have been observed in various tumors types, understanding of metabolic genotype-phenotype relationships is limited. METHODS We deployed an integrated approach combining genomics, metabolomics, and phenotypic analysis on a unique cohort of patient-derived pancreatic cancer cell lines (PDCLs). Genome analysis was performed via targeted sequencing of the mitochondrial genome (mtDNA) and nuclear genes encoding mitochondrial components and metabolic genes. Phenotypic characterization of PDCLs included measurement of cellular oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) using a Seahorse XF extracellular flux analyser, targeted metabolomics and pathway profiling, and radiolabelled glutamine tracing. RESULTS We identified 24 somatic mutations in the mtDNA of 12 patient-derived pancreatic cancer cell lines (PDCLs). A further 18 mutations were identified in a targeted study of ~1000 nuclear genes important for mitochondrial function and metabolism. Comparison with reference datasets indicated a strong selection bias for non-synonymous mutants with predicted functional effects. Phenotypic analysis showed metabolic changes consistent with mitochondrial dysfunction, including reduced oxygen consumption and increased glycolysis. Metabolomics and radiolabeled substrate tracing indicated the initiation of reductive glutamine metabolism and lipid synthesis in tumours. CONCLUSIONS The heterogeneous genomic landscape of pancreatic tumours may converge on a common metabolic phenotype, with individual tumours adapting to increased anabolic demands via different genetic mechanisms. Targeting resulting metabolic phenotypes may be a productive therapeutic strategy.
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Affiliation(s)
- Rae-Anne Hardie
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW Australia
| | - Ellen van Dam
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
| | - Mark Cowley
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
| | - Ting-Li Han
- School of Biological Sciences, University of Auckland, Auckland, 1142 New Zealand
| | - Seher Balaban
- Discipline of Physiology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, NSW 2006 Australia
| | - Marina Pajic
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW Australia
| | - Mark Pinese
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW Australia
| | - Mary Iconomou
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW Australia
| | - Robert F. Shearer
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW Australia
| | - Jessie McKenna
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
| | - David Miller
- Centre for Medical Genomics, Institute for Molecular Bioscience, University of Queensland, St. Lucia, QLD 4072 Australia
| | - Nicola Waddell
- Centre for Medical Genomics, Institute for Molecular Bioscience, University of Queensland, St. Lucia, QLD 4072 Australia
| | - John V. Pearson
- Centre for Medical Genomics, Institute for Molecular Bioscience, University of Queensland, St. Lucia, QLD 4072 Australia
| | - Sean M. Grimmond
- Centre for Medical Genomics, Institute for Molecular Bioscience, University of Queensland, St. Lucia, QLD 4072 Australia
| | - Australian Pancreatic Cancer Genome Initiative
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW Australia
- School of Biological Sciences, University of Auckland, Auckland, 1142 New Zealand
- Discipline of Physiology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, NSW 2006 Australia
- Centre for Medical Genomics, Institute for Molecular Bioscience, University of Queensland, St. Lucia, QLD 4072 Australia
- Mitochondrial Biology Unit, Wellcome Trust, Cambridge, CB2 0XY UK
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
- Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders, University of Sydney, Sydney, NSW 2006 Australia
- School of Medical Sciences, University of New South Wales, Sydney, NSW 2052 Australia
| | - Leonid Sazanov
- Mitochondrial Biology Unit, Wellcome Trust, Cambridge, CB2 0XY UK
| | - Andrew V. Biankin
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Silas Villas-Boas
- School of Biological Sciences, University of Auckland, Auckland, 1142 New Zealand
| | - Andrew J. Hoy
- Discipline of Physiology, School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, NSW 2006 Australia
- Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders, University of Sydney, Sydney, NSW 2006 Australia
| | - Nigel Turner
- School of Medical Sciences, University of New South Wales, Sydney, NSW 2052 Australia
| | - Darren N. Saunders
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW 2010 Australia
- School of Medical Sciences, University of New South Wales, Sydney, NSW 2052 Australia
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144
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Abstract
The report in 1988 that Leber Hereditary Optic Neuropathy (LHON) was the product of mitochondrial DNA (mtDNA) mutations provided the first demonstration of the clinical relevance of inherited mtDNA variation. From LHON studies, the medical importance was demonstrated for the mtDNA showing its coding for the most important energy genes, its maternal inheritance, its high mutation rate, its presence in hundreds to thousands of copies per cell, its quantitatively segregation of biallelic genotypes during both mitosis and meiosis, its preferential effect on the most energetic tissues including the eye and brain, its wide range of functional polymorphisms that predispose to common diseases, and its accumulation of mutations within somatic tissues providing the aging clock. These features of mtDNA genetics, in combination with the genetics of the 1-2000 nuclear DNA (nDNA) coded mitochondrial genes, is not only explaining the genetics of LHON but also providing a model for understanding the complexity of many common diseases. With the maturation of LHON biology and genetics, novel animal models for complex disease have been developed and new therapeutic targets and strategies envisioned, both pharmacological and genetic. Multiple somatic gene therapy approaches are being developed for LHON which are applicable to other mtDNA diseases. Moreover, the unique cytoplasmic genetics of the mtDNA has permitted the first successful human germline gene therapy via spindle nDNA transfer from mtDNA mutant oocytes to enucleated normal mtDNA oocytes. Such LHON lessons are actively being applied to common ophthalmological diseases like glaucoma and neurological diseases like Parkinsonism.
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145
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Brown DA, Perry JB, Allen ME, Sabbah HN, Stauffer BL, Shaikh SR, Cleland JGF, Colucci WS, Butler J, Voors AA, Anker SD, Pitt B, Pieske B, Filippatos G, Greene SJ, Gheorghiade M. Expert consensus document: Mitochondrial function as a therapeutic target in heart failure. Nat Rev Cardiol 2016; 14:238-250. [PMID: 28004807 PMCID: PMC5350035 DOI: 10.1038/nrcardio.2016.203] [Citation(s) in RCA: 477] [Impact Index Per Article: 59.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Heart failure is a pressing worldwide public-health problem with millions of patients having worsening heart failure. Despite all the available therapies, the condition carries a very poor prognosis. Existing therapies provide symptomatic and clinical benefit, but do not fully address molecular abnormalities that occur in cardiomyocytes. This shortcoming is particularly important given that most patients with heart failure have viable dysfunctional myocardium, in which an improvement or normalization of function might be possible. Although the pathophysiology of heart failure is complex, mitochondrial dysfunction seems to be an important target for therapy to improve cardiac function directly. Mitochondrial abnormalities include impaired mitochondrial electron transport chain activity, increased formation of reactive oxygen species, shifted metabolic substrate utilization, aberrant mitochondrial dynamics, and altered ion homeostasis. In this Consensus Statement, insights into the mechanisms of mitochondrial dysfunction in heart failure are presented, along with an overview of emerging treatments with the potential to improve the function of the failing heart by targeting mitochondria.
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Affiliation(s)
- David A Brown
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, 1035 Integrated Life Sciences Building, 1981 Kraft Drive, Blacksburg, Virginia 24060, USA
| | - Justin B Perry
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, 1035 Integrated Life Sciences Building, 1981 Kraft Drive, Blacksburg, Virginia 24060, USA
| | - Mitchell E Allen
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, 1035 Integrated Life Sciences Building, 1981 Kraft Drive, Blacksburg, Virginia 24060, USA
| | - Hani N Sabbah
- Division of Cardiovascular Medicine, Department of Medicine, Henry Ford Hospital, 2799 West Grand Boulevard, Detroit, Michigan 48202, USA
| | - Brian L Stauffer
- Division of Cardiology, Department of Medicine, University of Colorado Denver, 12700 East 19th Avenue, B139, Aurora, Colorado 80045, USA
| | - Saame Raza Shaikh
- Department of Biochemistry and Molecular Biology, East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, North Carolina 27834, USA
| | - John G F Cleland
- National Heart &Lung Institute, National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton &Harefield Hospitals, Imperial College, London, UK
| | - Wilson S Colucci
- Cardiovascular Medicine Section, Boston University School of Medicine and Boston Medical Center, 88 East Newton Street, C-8, Boston, Massachusetts 02118, USA
| | - Javed Butler
- Division of Cardiology, Health Sciences Center, T-16 Room 080, SUNY at Stony Brook, New York 11794, USA
| | - Adriaan A Voors
- University of Groningen, Department of Cardiology, University Medical Center Groningen, Groningen 9713 GZ, Netherlands
| | - Stefan D Anker
- Department of Innovative Clinical Trials, University Medical Centre Göttingen (UMG), Robert-Koch-Straße, D-37075, Göttingen, Germany
| | - Bertram Pitt
- University of Michigan School of Medicine, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109, USA
| | - Burkert Pieske
- Department of Cardiology, Charité University Medicine, Campus Virchow Klinikum, and German Heart Center Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Gerasimos Filippatos
- National and Kopodistrian University of Athens, School of Medicine, Heart Failure Unit, Department of Cardiology, Athens University Hospital Attikon, Rimini 1, Athens 12462, Greece
| | - Stephen J Greene
- Division of Cardiology, Duke University Medical Center, 2301 Erwin Road Suite 7400, Durham, North Carolina 27705, USA
| | - Mihai Gheorghiade
- Center for Cardiovascular Innovation, Northwestern University Feinberg School of Medicine, 201 East Huron, Galter 3-150, Chicago, Illinois 60611, USA
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146
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Etzler JC, Bollo M, Holstein D, Deng JJ, Perez V, Lin DT, Richardson A, Bai Y, Lechleiter JD. Cyclophilin D over-expression increases mitochondrial complex III activity and accelerates supercomplex formation. Arch Biochem Biophys 2016; 613:61-68. [PMID: 27916505 DOI: 10.1016/j.abb.2016.11.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/27/2016] [Accepted: 11/23/2016] [Indexed: 12/15/2022]
Abstract
Cyclophilin D (CyPD), a mitochondrial matrix protein, has been widely studied for its role in mitochondrial-mediated cell death. Unexpectedly, we previously discovered that overexpression of CyPD in a stable cell line, increased mitochondrial membrane potentials and enhanced cell survival under conditions of oxidative stress. Here, we investigated the underlying mechanisms responsible for these findings. Spectrophotometric measurements in isolated mitochondria revealed that overexpression of CyPD in HEK293 cells increased respiratory chain activity, but only for Complex III (CIII). Acute treatment of mitochondria with the immumosupressant cyclosporine A did not affect CIII activity. Expression levels of the CIII subunits cytochrome b and Rieske-FeS were elevated in HEK293 cells overexpressing CyPD. However, CIII activity was still significantly higher compared to control mitochondria, even when normalized by protein expression. Blue native gel electrophoresis and Western blot assays revealed a molecular interaction of CyPD with CIII and increased levels of supercomplexes in mitochondrial protein extracts. Radiolabeled protein synthesis in mitochondria showed that CIII assembly and formation of supercomplexes containing CIII were significantly faster when CyPD was overexpressed. Taken together, these data indicate that CyPD regulates mitochondrial metabolism, and likely cell survival, by promoting more efficient electrons flow through the respiratory chain via increased supercomplex formation.
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Affiliation(s)
- Julie C Etzler
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Mariana Bollo
- Instituto de Investigación Médica M y M Ferreyra, INIMEC-CONICET, Universidad Nacional de Córdoba, 5016, Argentina
| | - Deborah Holstein
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Janice Jianhong Deng
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Viviana Perez
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 73104, USA
| | - Da-Ting Lin
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - Arlan Richardson
- Department of Geriatrics, University of Oklahoma Health Science Center, Oklahoma City, OK, 73104, USA
| | - Yidong Bai
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - James D Lechleiter
- Department of Cell Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
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147
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Structure of Mammalian Respiratory Supercomplex I 1 III 2 IV 1. Cell 2016; 167:1598-1609.e10. [DOI: 10.1016/j.cell.2016.11.012] [Citation(s) in RCA: 251] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/27/2016] [Accepted: 11/03/2016] [Indexed: 01/14/2023]
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148
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Pileggi CA, Hedges CP, Segovia SA, Markworth JF, Durainayagam BR, Gray C, Zhang XD, Barnett MPG, Vickers MH, Hickey AJR, Reynolds CM, Cameron-Smith D. Maternal High Fat Diet Alters Skeletal Muscle Mitochondrial Catalytic Activity in Adult Male Rat Offspring. Front Physiol 2016; 7:546. [PMID: 27917127 PMCID: PMC5114294 DOI: 10.3389/fphys.2016.00546] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/28/2016] [Indexed: 12/29/2022] Open
Abstract
A maternal high-fat (HF) diet during pregnancy can lead to metabolic compromise, such as insulin resistance in adult offspring. Skeletal muscle mitochondrial dysfunction is one mechanism contributing to metabolic impairments in insulin resistant states. Therefore, the present study aimed to investigate whether mitochondrial dysfunction is evident in metabolically compromised offspring born to HF-fed dams. Sprague-Dawley dams were randomly assigned to receive a purified control diet (CD; 10% kcal from fat) or a high fat diet (HFD; 45% kcal from fat) for 10 days prior to mating, throughout pregnancy and during lactation. From weaning, all male offspring received a standard chow diet and soleus muscle was collected at day 150. Expression of the mitochondrial transcription factors nuclear respiratory factor-1 (NRF1) and mitochondrial transcription factor A (mtTFA) were downregulated in HF offspring. Furthermore, genes encoding the mitochondrial electron transport system (ETS) respiratory complex subunits were suppressed in HF offspring. Moreover, protein expression of the complex I subunit, NDUFB8, was downregulated in HF offspring (36%), which was paralleled by decreased maximal catalytic linked activity of complex I and III (40%). Together, these results indicate that exposure to a maternal HF diet during development may elicit lifelong mitochondrial alterations in offspring skeletal muscle.
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Affiliation(s)
| | - Christopher P Hedges
- College of Sport and Exercise Science, Institute of Sport, Exercise and Active Living, Victoria UniversityMelbourne, VIC, Australia; Applied Surgery and Metabolism Laboratory, School of Biological Sciences, University of AucklandAuckland, New Zealand
| | - Stephanie A Segovia
- Liggins Institute, University of AucklandAuckland, New Zealand; Gravida: National Centre for Growth and Development, University of AucklandAuckland, New Zealand
| | | | | | - Clint Gray
- Liggins Institute, University of AucklandAuckland, New Zealand; Gravida: National Centre for Growth and Development, University of AucklandAuckland, New Zealand
| | - Xiaoyuan D Zhang
- Liggins Institute, University of AucklandAuckland, New Zealand; Gravida: National Centre for Growth and Development, University of AucklandAuckland, New Zealand
| | - Matthew P G Barnett
- Food Nutrition and Health Team, Food and Bio-based Products Group, AgResearch Grasslands Palmerston North, New Zealand
| | - Mark H Vickers
- Liggins Institute, University of AucklandAuckland, New Zealand; Gravida: National Centre for Growth and Development, University of AucklandAuckland, New Zealand
| | - Anthony J R Hickey
- Applied Surgery and Metabolism Laboratory, School of Biological Sciences, University of Auckland Auckland, New Zealand
| | - Clare M Reynolds
- Liggins Institute, University of AucklandAuckland, New Zealand; Gravida: National Centre for Growth and Development, University of AucklandAuckland, New Zealand
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149
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Sousa JS, Mills DJ, Vonck J, Kühlbrandt W. Functional asymmetry and electron flow in the bovine respirasome. eLife 2016; 5. [PMID: 27830641 PMCID: PMC5117854 DOI: 10.7554/elife.21290] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 11/03/2016] [Indexed: 01/11/2023] Open
Abstract
Respirasomes are macromolecular assemblies of the respiratory chain complexes I, III and IV in the inner mitochondrial membrane. We determined the structure of supercomplex I1III2IV1 from bovine heart mitochondria by cryo-EM at 9 Å resolution. Most protein-protein contacts between complex I, III and IV in the membrane are mediated by supernumerary subunits. Of the two Rieske iron-sulfur cluster domains in the complex III dimer, one is resolved, indicating that this domain is immobile and unable to transfer electrons. The central position of the active complex III monomer between complex I and IV in the respirasome is optimal for accepting reduced quinone from complex I over a short diffusion distance of 11 nm, and delivering reduced cytochrome c to complex IV. The functional asymmetry of complex III provides strong evidence for directed electron flow from complex I to complex IV through the active complex III monomer in the mammalian supercomplex. DOI:http://dx.doi.org/10.7554/eLife.21290.001
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Affiliation(s)
- Joana S Sousa
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Deryck J Mills
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Janet Vonck
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Werner Kühlbrandt
- Department of Structural Biology, Max Planck Institute of Biophysics, Frankfurt, Germany
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150
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The Alterations in Mitochondrial DNA Copy Number and Nuclear-Encoded Mitochondrial Genes in Rat Brain Structures after Cocaine Self-Administration. Mol Neurobiol 2016; 54:7460-7470. [PMID: 27819115 PMCID: PMC5622911 DOI: 10.1007/s12035-016-0153-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 09/22/2016] [Indexed: 12/22/2022]
Abstract
The repeated intake of cocaine evokes oxidative stress that is present even during drug withdrawal. Recent studies demonstrate that cocaine-induced oxidative and/or endoplasmic reticulum stress can affect mitochondrial function and dynamics as well as the expression of mitochondrial and nuclear genes. These alterations in mitochondrial function may determine synaptic and behavioral plasticity. Mitochondria and mitochondrial DNA (mtDNA) seem to play an important role in the initiation of drug addiction. We used a microarray approach to investigate the expression patterns of nuclear-encoded genes relevant for mitochondrial functions and quantitative real-time PCR assays to determine the numbers of copies of mtDNA and of mRNAs corresponding to two mitochondrial proteins in the prefrontal cortex and hippocampus of rats during early cocaine abstinence. We found a significant elevation in the copy number of mtDNA and concomitant increased expression of mitochondrial genes. Moreover, microarray analysis revealed changes in the transcription of nuclear genes engaged in mtDNA replication, nucleoid formation, the oxidative phosphorylation pathway, and mitochondrial fission and fusion. Finally, we observed the upregulation of endoplasmic reticulum stress-induced genes. Cocaine self-administration influences the expression of both nuclear and mitochondrial genes as well as mtDNA replication. To determine whether these alterations serve as compensatory mechanisms to help maintain normal level of ATP production, further studies are necessary.
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