101
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Lee JW. Protonic Capacitor: Elucidating the biological significance of mitochondrial cristae formation. Sci Rep 2020; 10:10304. [PMID: 32601276 PMCID: PMC7324581 DOI: 10.1038/s41598-020-66203-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 04/17/2020] [Indexed: 11/12/2022] Open
Abstract
For decades, it was not entirely clear why mitochondria develop cristae? The work employing the transmembrane-electrostatic proton localization theory reported here has now provided a clear answer to this fundamental question. Surprisingly, the transmembrane-electrostatically localized proton concentration at a curved mitochondrial crista tip can be significantly higher than that at the relatively flat membrane plane regions where the proton-pumping respiratory supercomplexes are situated. The biological significance for mitochondrial cristae has now, for the first time, been elucidated at a protonic bioenergetics level: 1) The formation of cristae creates more mitochondrial inner membrane surface area and thus more protonic capacitance for transmembrane-electrostatically localized proton energy storage; and 2) The geometric effect of a mitochondrial crista enhances the transmembrane-electrostatically localized proton density to the crista tip where the ATP synthase can readily utilize the localized proton density to drive ATP synthesis.
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Affiliation(s)
- James Weifu Lee
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, 23529, USA.
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102
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Durairajanayagam D, Singh D, Agarwal A, Henkel R. Causes and consequences of sperm mitochondrial dysfunction. Andrologia 2020; 53:e13666. [PMID: 32510691 DOI: 10.1111/and.13666] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 05/07/2020] [Indexed: 12/15/2022] Open
Abstract
Mitochondria have multiple functions, including synthesis of adenine triphosphate, production of reactive oxygen species, calcium signalling, thermogenesis and apoptosis. Mitochondria have a significant contribution in regulating the various physiological aspects of reproductive function, from spermatogenesis up to fertilisation. Mitochondrial functionality and intact mitochondrial membrane potential are a pre-requisite for sperm motility, hyperactivation, capacitation, acrosin activity, acrosome reaction and DNA integrity. Optimal mitochondrial activity is therefore crucial for human sperm function and semen quality. However, the precise role of mitochondria in spermatozoa remains to be fully explored. Defects in sperm mitochondrial function severely impair the maintenance of energy production required for sperm motility and may be an underlying cause of asthenozoospermia. Sperm mtDNA is susceptible to oxidative damage and mutations that could compromise sperm function leading to infertility. Males with abnormal semen parameters have increased mtDNA copy number and reduced mtDNA integrity. This review discusses the role of mitochondria in sperm function, along with the causes and impact of its dysfunction on male fertility. Greater understanding of sperm mitochondrial function and its correlation with sperm quality could provide further insights into their contribution in the assessment of the infertile male.
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Affiliation(s)
- Damayanthi Durairajanayagam
- Department of Physiology, Faculty of Medicine, Universiti Teknologi MARA, Cawangan Selangor, Kampus Sungai Buloh, Sungai Buloh, Malaysia
| | - Dipty Singh
- Department of Neuroendocrinology, Indian Council of Medical Research (ICMR)-National Institute for Research in Reproductive Health (NIRRH), Mumbai, India
| | - Ashok Agarwal
- American Center for Reproductive Medicine, Cleveland Clinic, Cleveland, OH, USA
| | - Ralf Henkel
- American Center for Reproductive Medicine, Cleveland Clinic, Cleveland, OH, USA.,Department of Medical Bioscience, Faculty of Natural Science, University of the Western Cape, Belville, South Africa
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103
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Colina-Tenorio L, Horten P, Pfanner N, Rampelt H. Shaping the mitochondrial inner membrane in health and disease. J Intern Med 2020; 287:645-664. [PMID: 32012363 DOI: 10.1111/joim.13031] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 12/19/2019] [Accepted: 01/20/2020] [Indexed: 12/16/2022]
Abstract
Mitochondria play central roles in cellular energetics, metabolism and signalling. Efficient respiration, mitochondrial quality control, apoptosis and inheritance of mitochondrial DNA depend on the proper architecture of the mitochondrial membranes and a dynamic remodelling of inner membrane cristae. Defects in mitochondrial architecture can result in severe human diseases affecting predominantly the nervous system and the heart. Inner membrane morphology is generated and maintained in particular by the mitochondrial contact site and cristae organizing system (MICOS), the F1 Fo -ATP synthase, the fusion protein OPA1/Mgm1 and the nonbilayer-forming phospholipids cardiolipin and phosphatidylethanolamine. These protein complexes and phospholipids are embedded in a network of functional interactions. They communicate with each other and additional factors, enabling them to balance different aspects of cristae biogenesis and to dynamically remodel the inner mitochondrial membrane. Genetic alterations disturbing these membrane-shaping factors can lead to human pathologies including fatal encephalopathy, dominant optic atrophy, Leigh syndrome, Parkinson's disease and Barth syndrome.
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Affiliation(s)
- L Colina-Tenorio
- From the, Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - P Horten
- From the, Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - N Pfanner
- From the, Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.,BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - H Rampelt
- From the, Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
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104
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Abstract
Mitochondria are essential for eukaryotic life. These double-membrane organelles often form highly dynamic tubular networks interacting with many cellular structures. Their highly convoluted contiguous inner membrane compartmentalizes the organelle, which is crucial for mitochondrial function. Since the diameter of the mitochondrial tubules is generally close to the diffraction limit of light microscopy, it is often challenging, if not impossible, to visualize submitochondrial structures or protein distributions using conventional light microscopy. This renders super-resolution microscopy particularly valuable, and attractive, for studying mitochondria. Super-resolution microscopy encompasses a diverse set of approaches that extend resolution, as well as nanoscopy techniques that can even overcome the diffraction limit. In this review, we provide an overview of recent studies using super-resolution microscopy to investigate mitochondria, discuss the strengths and opportunities of the various methods in addressing specific questions in mitochondrial biology, and highlight potential future developments.
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Affiliation(s)
- Stefan Jakobs
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany;
- Clinic of Neurology, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Till Stephan
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany;
- Clinic of Neurology, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Peter Ilgen
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany;
- Clinic of Neurology, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Christian Brüser
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany;
- Clinic of Neurology, University Medical Center Göttingen, 37075 Göttingen, Germany
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105
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A Comparative Study of the Action of Protonophore Uncouplers and Decoupling Agents as Inducers of Free Respiration in Mitochondria in States 3 and 4: Theoretical and Experimental Approaches. Cell Biochem Biophys 2020; 78:203-216. [PMID: 32367259 DOI: 10.1007/s12013-020-00914-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/17/2020] [Indexed: 02/07/2023]
Abstract
Theoretical and experimental studies have revealed that that in the liver mitochondria an increase in the rate of free respiration in state 3 induced by protonophore uncouplers 2,4-dinitrophenol and сarbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone is equal to or slightly greater than the increase in respiration rate in state 4 induced by these uncouplers. In contrast to these protonophore uncouplers, the decoupler α,ω-tetradecanedioic acid, increasing the rate of respiration in state 4, does not significantly affect the rate of free respiration in state 3. We have proposed quantitative indicators that allow determining the constituent part of the rate of respiration in state 4, associated with the decoupling effect of the uncoupler. Using the example of palmitic acid, we have found out the fundamental possibility of the simultaneous functioning of uncouplers by two mechanisms: as protonophores and as decouplers. The data obtained contradict the delocalized version of Mitchell's chemiosmotic theory, but are in complete agreement with its local version. It can be assumed that the F0F1-ATP synthase and nearby respiratory chain complexes form a local zone of coupled respiration and oxidative ATP synthesis (zones of oxidative phosphorylation). The uncoupler-induced stimulation of mitochondrial free respiration of mitochondria in state 3 is mainly due to the return of protons to the matrix in local zones, where the generation of a proton motive force (Δр) by respiratory chain complexes is associated with various transport processes, but not with ATP synthesis (zones of protonophore uncoupling). In contrast, respiratory stimulation in state 4 by decouplers is realized in local zones of oxidative phosphorylation by switching the respiratory chain complexes to the idle mode of operation in the absence of ATP synthesis.
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106
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Ultrastructural analysis of the dehydrated tardigrade Hypsibius exemplaris unveils an anhydrobiotic-specific architecture. Sci Rep 2020; 10:4324. [PMID: 32152342 PMCID: PMC7062702 DOI: 10.1038/s41598-020-61165-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 02/18/2020] [Indexed: 01/06/2023] Open
Abstract
Tardigrades can cope with adverse environmental conditions by turning into anhydrobiotes with a characteristic tun shape. Tun formation is an essential morphological adaptation for tardigrade entry into the anhydrobiotic state. The tun cell structure and ultrastructure have rarely been explored in tardigrades in general and never in Hypsibius exemplaris. We used transmission electron microscopy to compare cellular organization and ultrastructures between hydrated and anhydrobiotic H. exemplaris. Despite a globally similar cell organelle structure and a number of cells not significantly different between hydrated and desiccated tardigrades, reductions in the sizes of both cells and mitochondria were detected in dehydrated animals. Moreover, in anhydrobiotes, secretory active cells with a dense endoplasmic reticulum network were observed. Interestingly, these anhydrobiote-specific cells are in a close relationship with a specific extracellular structure surrounding each cell. It is possible that this rampart-like extracellular structure resulted from the accumulation of anhydrobiotic-specific material to protect the cells. Interestingly, after five hours of rehydration, the number of secretory cells decreased, and the specific extracellular structure began to disappear. Twenty-four hours after the beginning of rehydration, the cellular structure and ultrastructure were comparable to those observed in hydrated tardigrades.
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107
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Busch KB. Inner mitochondrial membrane compartmentalization: Dynamics across scales. Int J Biochem Cell Biol 2020; 120:105694. [DOI: 10.1016/j.biocel.2020.105694] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 12/23/2019] [Accepted: 01/09/2020] [Indexed: 01/08/2023]
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108
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Kondadi AK, Anand R, Hänsch S, Urbach J, Zobel T, Wolf DM, Segawa M, Liesa M, Shirihai OS, Weidtkamp-Peters S, Reichert AS. Cristae undergo continuous cycles of membrane remodelling in a MICOS-dependent manner. EMBO Rep 2020; 21:e49776. [PMID: 32067344 PMCID: PMC7054676 DOI: 10.15252/embr.201949776] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 11/09/2022] Open
Abstract
The mitochondrial inner membrane can reshape under different physiological conditions. How, at which frequency this occurs in living cells, and the molecular players involved are unknown. Here, we show using state-of-the-art live-cell stimulated emission depletion (STED) super-resolution nanoscopy that neighbouring crista junctions (CJs) dynamically appose and separate from each other in a reversible and balanced manner in human cells. Staining of cristae membranes (CM), using various protein markers or two lipophilic inner membrane-specific dyes, further revealed that cristae undergo continuous cycles of membrane remodelling. These events are accompanied by fluctuations of the membrane potential within distinct cristae over time. Both CJ and CM dynamics depended on MIC13 and occurred at similar timescales in the range of seconds. Our data further suggest that MIC60 acts as a docking platform promoting CJ and contact site formation. Overall, by employing advanced imaging techniques including fluorescence recovery after photobleaching (FRAP), single-particle tracking (SPT), live-cell STED and high-resolution Airyscan microscopy, we propose a model of CJ dynamics being mechanistically linked to CM remodelling representing cristae membrane fission and fusion events occurring within individual mitochondria.
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Affiliation(s)
- Arun Kumar Kondadi
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ruchika Anand
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Sebastian Hänsch
- Faculty of Mathematics and Natural Sciences, Center for Advanced Imaging, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jennifer Urbach
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Thomas Zobel
- Faculty of Mathematics and Natural Sciences, Center for Advanced Imaging, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Dane M Wolf
- Department of Medicine, Nutrition and Metabolism Section, Evans Biomedical Research Center, Boston University School of Medicine, Boston, MA, USA.,Division of Endocrinology, Department of Medicine, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Mayuko Segawa
- Division of Endocrinology, Department of Medicine, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Marc Liesa
- Division of Endocrinology, Department of Medicine, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA.,Molecular Biology Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Orian S Shirihai
- Department of Medicine, Nutrition and Metabolism Section, Evans Biomedical Research Center, Boston University School of Medicine, Boston, MA, USA.,Division of Endocrinology, Department of Medicine, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Stefanie Weidtkamp-Peters
- Faculty of Mathematics and Natural Sciences, Center for Advanced Imaging, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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109
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Abstract
Owing to their ability to efficiently generate ATP required to sustain normal cell function, mitochondria are often considered the 'powerhouses of the cell'. However, our understanding of the role of mitochondria in cell biology recently expanded when we recognized that they are key platforms for a plethora of cell signalling cascades. This functional versatility is tightly coupled to constant reshaping of the cellular mitochondrial network in a series of processes, collectively referred to as mitochondrial membrane dynamics and involving organelle fusion and fission (division) as well as ultrastructural remodelling of the membrane. Accordingly, mitochondrial dynamics influence and often orchestrate not only metabolism but also complex cell signalling events, such as those involved in regulating cell pluripotency, division, differentiation, senescence and death. Reciprocally, mitochondrial membrane dynamics are extensively regulated by post-translational modifications of its machinery and by the formation of membrane contact sites between mitochondria and other organelles, both of which have the capacity to integrate inputs from various pathways. Here, we discuss mitochondrial membrane dynamics and their regulation and describe how bioenergetics and cellular signalling are linked to these dynamic changes of mitochondrial morphology.
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110
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Kinetic coupling of the respiratory chain with ATP synthase, but not proton gradients, drives ATP production in cristae membranes. Proc Natl Acad Sci U S A 2020; 117:2412-2421. [PMID: 31964824 DOI: 10.1073/pnas.1917968117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Mitochondria have a characteristic ultrastructure with invaginations of the inner membrane called cristae that contain the protein complexes of the oxidative phosphorylation system. How this particular morphology of the respiratory membrane impacts energy conversion is currently unknown. One proposed role of cristae formation is to facilitate the establishment of local proton gradients to fuel ATP synthesis. Here, we determined the local pH values at defined sublocations within mitochondria of respiring yeast cells by fusing a pH-sensitive GFP to proteins residing in different mitochondrial subcompartments. Only a small proton gradient was detected over the inner membrane in wild type or cristae-lacking cells. Conversely, the obtained pH values did barely permit ATP synthesis in a reconstituted system containing purified yeast F1F0 ATP synthase, although, thermodynamically, a sufficiently high driving force was applied. At higher driving forces, where robust ATP synthesis was observed, a P-side pH value of 6 increased the ATP synthesis rate 3-fold compared to pH 7. In contrast, when ATP synthase was coreconstituted with an active proton-translocating cytochrome oxidase, ATP synthesis readily occurred at the measured, physiological pH values. Our study thus reveals that the morphology of the inner membrane does not influence the subcompartmental pH values and is not necessary for robust oxidative phosphorylation in mitochondria. Instead, it is likely that the dense packing of the oxidative phosphorylation complexes in the cristae membranes assists kinetic coupling between proton pumping and ATP synthesis.
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111
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Liesa M. Why does a mitochondrion need its individual cristae to be functionally autonomous? Mol Cell Oncol 2020; 7:1705119. [PMID: 32158918 PMCID: PMC7051166 DOI: 10.1080/23723556.2019.1705119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 11/20/2022]
Abstract
We demonstrated that individual cristae in one mitochondrion function as autonomous electrochemical units, with this autonomy being maintained by cristae junction modulators. Here, I will summarize our novel findings, discuss the advantages of cristae insulation and reconcile this newly characterized cristae autonomy with previous studies showing coordinated cristae function.
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Affiliation(s)
- Marc Liesa
- Department of Medicine, Endocrinology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,Molecular Biology Institute at UCLA, Loa Angeles, CA, USA
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112
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Mitochondrial morphology provides a mechanism for energy buffering at synapses. Sci Rep 2019; 9:18306. [PMID: 31797946 PMCID: PMC6893035 DOI: 10.1038/s41598-019-54159-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/24/2019] [Indexed: 01/27/2023] Open
Abstract
Mitochondria as the main energy suppliers of eukaryotic cells are highly dynamic organelles that fuse, divide and are transported along the cytoskeleton to ensure cellular energy homeostasis. While these processes are well established, substantial evidence indicates that the internal structure is also highly variable in dependence on metabolic conditions. However, a quantitative mechanistic understanding of how mitochondrial morphology affects energetic states is still elusive. To address this question, we here present an agent-based multiscale model that integrates three-dimensional morphologies from electron microscopy tomography with the molecular dynamics of the main ATP producing components. We apply our modeling approach to mitochondria at the synapse which is the largest energy consumer within the brain. Interestingly, comparing the spatiotemporal simulations with a corresponding space-independent approach, we find minor spatial effects when the system relaxes toward equilibrium but a qualitative difference in fluctuating environments. These results suggest that internal mitochondrial morphology is not only optimized for ATP production but also provides a mechanism for energy buffering and may represent a mechanism for cellular robustness.
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113
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Salewskij K, Rieger B, Hager F, Arroum T, Duwe P, Villalta J, Colgiati S, Richter CP, Psathaki OE, Enriquez JA, Dellmann T, Busch KB. The spatio-temporal organization of mitochondrial F 1F O ATP synthase in cristae depends on its activity mode. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1861:148091. [PMID: 31669489 DOI: 10.1016/j.bbabio.2019.148091] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 10/02/2019] [Accepted: 10/18/2019] [Indexed: 12/11/2022]
Abstract
F1FO ATP synthase, also known as complex V, is a key enzyme of mitochondrial energy metabolism that can synthesize and hydrolyze ATP. It is not known whether the ATP synthase and ATPase function are correlated with a different spatio-temporal organisation of the enzyme. In order to analyze this, we tracked and localized single ATP synthase molecules in situ using live cell microscopy. Under normal conditions, complex V was mainly restricted to cristae indicated by orthogonal trajectories along the cristae membranes. In addition confined trajectories that are quasi immobile exist. By inhibiting glycolysis with 2-DG, the activity and mobility of complex V was altered. The distinct cristae-related orthogonal trajectories of complex V were obliterated. Moreover, a mobile subpopulation of complex V was found in the inner boundary membrane. The observed changes in the ratio of dimeric/monomeric complex V, respectively less mobile/more mobile complex V and its activity changes were reversible. In IF1-KO cells, in which ATP hydrolysis is not inhibited by IF1, complex V was more mobile, while inhibition of ATP hydrolysis by BMS-199264 reduced the mobility of complex V. Taken together, these data support the existence of different subpopulations of complex V, ATP synthase and ATP hydrolase, the latter with higher mobility and probably not prevailing at the cristae edges. Obviously, complex V reacts quickly and reversibly to metabolic conditions, not only by functional, but also by spatial and structural reorganization.
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Affiliation(s)
- Kirill Salewskij
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Bettina Rieger
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Frances Hager
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Tasnim Arroum
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Patrick Duwe
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Jimmy Villalta
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Sara Colgiati
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, 28029 Madrid, Catania, Spain; Institute of Nutrition and Food Technology, Biomedical Research Centre, Department of Physiology, University of Granada, Granada, Andalusia, Spain
| | - Christian P Richter
- University of Osnabrück, School of Biology, University of Osnabrück, 49076 Osnabrück, Lower Saxony, Germany; Center of Cellular Nanoanalytics, Integrated Bioimaging Facility, University of Osnabrück, 49076 Osnabrück, Lower Saxony, Germany
| | - Olympia E Psathaki
- University of Osnabrück, School of Biology, University of Osnabrück, 49076 Osnabrück, Lower Saxony, Germany; Center of Cellular Nanoanalytics, Integrated Bioimaging Facility, University of Osnabrück, 49076 Osnabrück, Lower Saxony, Germany
| | - José A Enriquez
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, 28029 Madrid, Catania, Spain
| | - Timo Dellmann
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany
| | - Karin B Busch
- University Münster, Department of Biology, Institute of Molecular Cell Biology, 48149 Münster, North Rhine-Westphalia, Germany.
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114
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Wolf DM, Segawa M, Kondadi AK, Anand R, Bailey ST, Reichert AS, van der Bliek AM, Shackelford DB, Liesa M, Shirihai OS. Individual cristae within the same mitochondrion display different membrane potentials and are functionally independent. EMBO J 2019; 38:e101056. [PMID: 31609012 PMCID: PMC6856616 DOI: 10.15252/embj.2018101056] [Citation(s) in RCA: 193] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 08/12/2019] [Accepted: 09/05/2019] [Indexed: 11/17/2022] Open
Abstract
The mitochondrial membrane potential (ΔΨm ) is the main driver of oxidative phosphorylation (OXPHOS). The inner mitochondrial membrane (IMM), consisting of cristae and inner boundary membranes (IBM), is considered to carry a uniform ΔΨm . However, sequestration of OXPHOS components in cristae membranes necessitates a re-examination of the equipotential representation of the IMM. We developed an approach to monitor ΔΨm at the resolution of individual cristae. We found that the IMM was divided into segments with distinct ΔΨm , corresponding to cristae and IBM. ΔΨm was higher at cristae compared to IBM. Treatment with oligomycin increased, whereas FCCP decreased, ΔΨm heterogeneity along the IMM. Impairment of cristae structure through deletion of MICOS-complex components or Opa1 diminished this intramitochondrial heterogeneity of ΔΨm . Lastly, we determined that different cristae within the individual mitochondrion can have disparate membrane potentials and that interventions causing acute depolarization may affect some cristae while sparing others. Altogether, our data support a new model in which cristae within the same mitochondrion behave as independent bioenergetic units, preventing the failure of specific cristae from spreading dysfunction to the rest.
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Affiliation(s)
- Dane M Wolf
- Department of Medicine (Endocrinology)Department of Molecular and Medical PharmacologyDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
- Graduate Program in Nutrition and MetabolismGraduate Medical SciencesBoston University School of MedicineBostonMAUSA
| | - Mayuko Segawa
- Department of Medicine (Endocrinology)Department of Molecular and Medical PharmacologyDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
| | - Arun Kumar Kondadi
- Institute of Biochemistry and Molecular Biology IMedical FacultyHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Ruchika Anand
- Institute of Biochemistry and Molecular Biology IMedical FacultyHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Sean T Bailey
- Department of Pulmonary and Critical Care MedicineDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
- Jonsson Comprehensive Cancer CenterDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
- Lineberger Comprehensive Cancer CenterUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology IMedical FacultyHeinrich Heine University DüsseldorfDüsseldorfGermany
| | - Alexander M van der Bliek
- Molecular Biology Institute at UCLALos AngelesCAUSA
- Department of Biological ChemistryDavid Geffen School of Medicine at UCLALos AngelesCAUSA
| | - David B Shackelford
- Department of Pulmonary and Critical Care MedicineDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
- Jonsson Comprehensive Cancer CenterDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
| | - Marc Liesa
- Department of Medicine (Endocrinology)Department of Molecular and Medical PharmacologyDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
- Molecular Biology Institute at UCLALos AngelesCAUSA
| | - Orian S Shirihai
- Department of Medicine (Endocrinology)Department of Molecular and Medical PharmacologyDavid Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA
- Graduate Program in Nutrition and MetabolismGraduate Medical SciencesBoston University School of MedicineBostonMAUSA
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115
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Madreiter-Sokolowski CT, Ramadani-Muja J, Ziomek G, Burgstaller S, Bischof H, Koshenov Z, Gottschalk B, Malli R, Graier WF. Tracking intra- and inter-organelle signaling of mitochondria. FEBS J 2019; 286:4378-4401. [PMID: 31661602 PMCID: PMC6899612 DOI: 10.1111/febs.15103] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/19/2019] [Accepted: 10/22/2019] [Indexed: 12/15/2022]
Abstract
Mitochondria are as highly specialized organelles and masters of the cellular energy metabolism in a constant and dynamic interplay with their cellular environment, providing adenosine triphosphate, buffering Ca2+ and fundamentally contributing to various signaling pathways. Hence, such broad field of action within eukaryotic cells requires a high level of structural and functional adaptation. Therefore, mitochondria are constantly moving and undergoing fusion and fission processes, changing their shape and their interaction with other organelles. Moreover, mitochondrial activity gets fine-tuned by intra- and interorganelle H+ , K+ , Na+ , and Ca2+ signaling. In this review, we provide an up-to-date overview on mitochondrial strategies to adapt and respond to, as well as affect, their cellular environment. We also present cutting-edge technologies used to track and investigate subcellular signaling, essential to the understanding of various physiological and pathophysiological processes.
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Affiliation(s)
- Corina T Madreiter-Sokolowski
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria.,Department of Health Sciences and Technology, ETH Zurich, Schwerzenbach, Switzerland
| | - Jeta Ramadani-Muja
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Gabriela Ziomek
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Sandra Burgstaller
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Helmut Bischof
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Zhanat Koshenov
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Benjamin Gottschalk
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria
| | - Roland Malli
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria.,BioTechMed, Graz, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Austria.,BioTechMed, Graz, Austria
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Wagner F, Kunz TC, Chowdhury SR, Thiede B, Fraunholz M, Eger D, Kozjak-Pavlovic V. Armadillo repeat-containing protein 1 is a dual localization protein associated with mitochondrial intermembrane space bridging complex. PLoS One 2019; 14:e0218303. [PMID: 31644573 PMCID: PMC6808451 DOI: 10.1371/journal.pone.0218303] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 10/08/2019] [Indexed: 02/03/2023] Open
Abstract
Cristae architecture is important for the function of mitochondria, the organelles that play the central role in many cellular processes. The mitochondrial contact site and cristae organizing system (MICOS) together with the sorting and assembly machinery (SAM) forms the mitochondrial intermembrane space bridging complex (MIB), a large protein complex present in mammalian mitochondria that partakes in the formation and maintenance of cristae. We report here a new subunit of the mammalian MICOS/MIB complex, an armadillo repeat-containing protein 1 (ArmC1). ArmC1 localizes both to cytosol and mitochondria, where it associates with the outer mitochondrial membrane through its carboxy-terminus. ArmC1 interacts with other constituents of the MICOS/MIB complex and its amounts are reduced upon MICOS/MIB complex depletion. Mitochondria lacking ArmC1 do not show defects in cristae structure, respiration or protein content, but appear fragmented and with reduced motility. ArmC1 represents therefore a peripheral MICOS/MIB component that appears to play a role in mitochondrial distribution in the cell.
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Affiliation(s)
- Fabienne Wagner
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Tobias C. Kunz
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Suvagata R. Chowdhury
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Bernd Thiede
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Martin Fraunholz
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Debora Eger
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Vera Kozjak-Pavlovic
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
- * E-mail:
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117
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Abstract
The mitochondrial inner membrane consists of the inner boundary membrane and invaginations called cristae, which differ in protein composition and likely have distinct functions. In this issue of The EMBO Journal, Wolf et al (2019) report that the cristae carry a higher membrane potential than the intervening boundary membranes. Their data suggest electro-chemical discontinuity among segments of the inner membrane, implying that individual cristae may operate with some degree of independence.
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Affiliation(s)
- Michael Schlame
- Departments of Anesthesiology and Cell Biology, New York University School of Medicine, New York, NY, USA
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118
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Kondadi AK, Anand R, Reichert AS. Functional Interplay between Cristae Biogenesis, Mitochondrial Dynamics and Mitochondrial DNA Integrity. Int J Mol Sci 2019; 20:ijms20174311. [PMID: 31484398 PMCID: PMC6747513 DOI: 10.3390/ijms20174311] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/30/2019] [Accepted: 08/30/2019] [Indexed: 12/11/2022] Open
Abstract
Mitochondria are vital cellular organelles involved in a plethora of cellular processes such as energy conversion, calcium homeostasis, heme biogenesis, regulation of apoptosis and ROS reactive oxygen species (ROS) production. Although they are frequently depicted as static bean-shaped structures, our view has markedly changed over the past few decades as many studies have revealed a remarkable dynamicity of mitochondrial shapes and sizes both at the cellular and intra-mitochondrial levels. Aberrant changes in mitochondrial dynamics and cristae structure are associated with ageing and numerous human diseases (e.g., cancer, diabetes, various neurodegenerative diseases, types of neuro- and myopathies). Another unique feature of mitochondria is that they harbor their own genome, the mitochondrial DNA (mtDNA). MtDNA exists in several hundreds to thousands of copies per cell and is arranged and packaged in the mitochondrial matrix in structures termed mt-nucleoids. Many human diseases are mechanistically linked to mitochondrial dysfunction and alteration of the number and/or the integrity of mtDNA. In particular, several recent studies identified remarkable and partly unexpected links between mitochondrial structure, fusion and fission dynamics, and mtDNA. In this review, we will provide an overview about these recent insights and aim to clarify how mitochondrial dynamics, cristae ultrastructure and mtDNA structure influence each other and determine mitochondrial functions.
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Affiliation(s)
- Arun Kumar Kondadi
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Ruchika Anand
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Andreas S Reichert
- Institute of Biochemistry and Molecular Biology I, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany.
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119
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Gottschalk B, Klec C, Leitinger G, Bernhart E, Rost R, Bischof H, Madreiter-Sokolowski CT, Radulović S, Eroglu E, Sattler W, Waldeck-Weiermair M, Malli R, Graier WF. MICU1 controls cristae junction and spatially anchors mitochondrial Ca 2+ uniporter complex. Nat Commun 2019; 10:3732. [PMID: 31427612 PMCID: PMC6700202 DOI: 10.1038/s41467-019-11692-x] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 07/30/2019] [Indexed: 12/15/2022] Open
Abstract
Recently identified core proteins (MICU1, MCU, EMRE) forming the mitochondrial Ca2+ uniporter complex propelled investigations into its physiological workings. Here, we apply structured illumination microscopy to visualize and localize these proteins in living cells. Our data show that MICU1 localizes at the inner boundary membrane (IBM) due to electrostatic interaction of its polybasic domain. Moreover, this exclusive localization of MICU1 is important for the stability of cristae junctions (CJ), cytochrome c release and mitochondrial membrane potential. In contrast to MICU1, MCU and EMRE are homogeneously distributed at the inner mitochondrial membrane under resting conditions. However, upon Ca2+ elevation MCU and EMRE dynamically accumulate at the IBM in a MICU1-dependent manner. Eventually, our findings unveil an essential function of MICU1 in CJ stabilization and provide mechanistic insights of how sophistically MICU1 controls the MCU-Complex while maintaining the structural mitochondrial membrane framework.
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Affiliation(s)
- Benjamin Gottschalk
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Christiane Klec
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Gerd Leitinger
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Cell Biology, Histology and Embryology, Medical University of Graz, Neue Stiftingtalstraße 6/2, 8010 Graz, Austria
| | - Eva Bernhart
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - René Rost
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Helmut Bischof
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Corina T. Madreiter-Sokolowski
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Snježana Radulović
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria ,0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Cell Biology, Histology and Embryology, Medical University of Graz, Neue Stiftingtalstraße 6/2, 8010 Graz, Austria
| | - Emrah Eroglu
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Wolfgang Sattler
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed Graz, Mozartgasse 12/2, Graz, 8010 Austria
| | - Markus Waldeck-Weiermair
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria
| | - Roland Malli
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed Graz, Mozartgasse 12/2, Graz, 8010 Austria
| | - Wolfgang F. Graier
- 0000 0000 8988 2476grid.11598.34Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed Graz, Mozartgasse 12/2, Graz, 8010 Austria
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120
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Beltrán-Heredia E, Tsai FC, Salinas-Almaguer S, Cao FJ, Bassereau P, Monroy F. Membrane curvature induces cardiolipin sorting. Commun Biol 2019; 2:225. [PMID: 31240263 PMCID: PMC6586900 DOI: 10.1038/s42003-019-0471-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 05/23/2019] [Indexed: 11/17/2022] Open
Abstract
Cardiolipin is a cone-shaped lipid predominantly localized in curved membrane sites of bacteria and in the mitochondrial cristae. This specific localization has been argued to be geometry-driven, since the CL's conical shape relaxes curvature frustration. Although previous evidence suggests a coupling between CL concentration and membrane shape in vivo, no precise experimental data are available for curvature-based CL sorting in vitro. Here, we test this hypothesis in experiments that isolate the effects of membrane curvature in lipid-bilayer nanotubes. CL sorting is observed with increasing tube curvature, reaching a maximum at optimal CL concentrations, a fact compatible with self-associative clustering. Observations are compatible with a model of membrane elasticity including van der Waals entropy, from which a negative intrinsic curvature of -1.1 nm-1 is predicted for CL. The results contribute to understanding the physicochemical interplay between membrane curvature and composition, providing key insights into mitochondrial and bacterial membrane organization and dynamics.
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Affiliation(s)
- Elena Beltrán-Heredia
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Plaza de Ciencias, 1, 28040 Madrid, Spain
- Departamento de Química Física, Universidad Complutense de Madrid, Avda. Complutense, s/n, 28040 Madrid, Spain
| | - Feng-Ching Tsai
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, 75005 Paris, France
| | - Samuel Salinas-Almaguer
- Departamento de Química Física, Universidad Complutense de Madrid, Avda. Complutense, s/n, 28040 Madrid, Spain
| | - Francisco J. Cao
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Plaza de Ciencias, 1, 28040 Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia, IMDEA Nanociencia, Calle Faraday, 9, 28049 Madrid, Spain
| | - Patricia Bassereau
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, 75005 Paris, France
- Sorbonne Université, UPMC Univ Paris 06, 75005 Paris, France
| | - Francisco Monroy
- Departamento de Química Física, Universidad Complutense de Madrid, Avda. Complutense, s/n, 28040 Madrid, Spain
- Unit of Translational Biophysics, Instituto de Investigación Sanitaria Hospital Doce de Octubre (imas12), Avda. de Córdoba, s/n, 28041 Madrid, Spain
- Institute for Quantitative Biosciences-QB3, University of California at Berkeley, Berkeley, CA 94720 USA
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121
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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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122
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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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123
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Zhang S. MGARP is ultrastructurally located in the inner faces of mitochondrial membranes. Biochem Biophys Res Commun 2019; 516:138-143. [PMID: 31202457 DOI: 10.1016/j.bbrc.2019.06.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 06/06/2019] [Indexed: 12/22/2022]
Abstract
Mitochondria, the centers of energy production, are highly organized with inner membranes, cristae and outer membranes. The mitochondrial architecture determines their functions in all cellular processes. Changes in the mitochondrial ultrastructure are tightly related to a wide variety of diseases. MGARP, a mitochondria-localized protein, was predicted by bioinformatics and confirmed by cellular and biochemical methods to be located in mitochondria, but there is no direct and clear evidence for its precise location. This report demonstrates the precise ultrastructural location of MGARP within mitochondria by the ascorbate peroxidase 2 (APEX2) system in combination with electron microscopy (EM). EM revealed that more MGARP is located in the inner/cristae membranes, with its C-terminus at the inner faces of the intramembrane spaces, than in the outer membranes. MGARP overexpression caused both mitochondrial remodeling and cristae shaping, leading to the collapse of the mitochondrial network. The mitochondrial morphologies in MGARP-overexpressing cells were diverse; the cells became round or short, and their cristae were deformed and became discontinuous or circular. An engineered MGARP mutant deficient in its transmembrane domain no longer localized to the mitochondria and lost its effects on mitochondrial structure, confirming that the localization of MGARP in the mitochondria depends on its structural integrity. Collectively, our findings define the location of MGARP within the mitochondria, which is associated with its functional implications for the architecture and organization of mitochondria.
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Affiliation(s)
- Shuping Zhang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China.
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124
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Callegari S, Müller T, Schulz C, Lenz C, Jans DC, Wissel M, Opazo F, Rizzoli SO, Jakobs S, Urlaub H, Rehling P, Deckers M. A MICOS-TIM22 Association Promotes Carrier Import into Human Mitochondria. J Mol Biol 2019; 431:2835-2851. [PMID: 31103774 DOI: 10.1016/j.jmb.2019.05.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/10/2019] [Accepted: 05/10/2019] [Indexed: 01/05/2023]
Abstract
Mitochondrial membrane proteins with internal targeting signals are inserted into the inner membrane by the carrier translocase (TIM22 complex). For this, precursors have to be initially directed from the TOM complex in the outer mitochondrial membrane across the intermembrane space toward the TIM22 complex. How these two translocation processes are topologically coordinated is still unresolved. Using proteomic approaches, we find that the human TIM22 complex associates with the mitochondrial contact site and cristae organizing system (MICOS) complex. This association does not appear to be conserved in yeast, whereby the yeast MICOS complex instead interacts with the presequence translocase. Using a yeast mic10Δ strain and a HEK293T MIC10 knockout cell line, we characterize the role of MICOS for protein import into the mitochondrial inner membrane and matrix. We find that a physiological cristae organization promotes efficient import via the presequence pathway in yeast, while in human mitochondria, the MICOS complex is dispensable for protein import along the presequence pathway. However, in human mitochondria, the MICOS complex is required for the efficient import of carrier proteins into the mitochondrial inner membrane. Our analyses suggest that in human mitochondria, positioning of the carrier translocase at the crista junction, and potentially in vicinity to the TOM complex, is required for efficient transport into the inner membrane.
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Affiliation(s)
- Sylvie Callegari
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Tobias Müller
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Christian Schulz
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Christof Lenz
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; Department of Clinical Chemistry, Bioanalytics, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Daniel C Jans
- Department of NanoBiophotonics, Mitochondrial Structure and Dynamics Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg, 11 37077 Göttingen, Germany; Clinic for Neurology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Mirjam Wissel
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Felipe Opazo
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, von-Siebold-Strasse 3a, 37075 Göttingen, Germany; Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Silvio O Rizzoli
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, von-Siebold-Strasse 3a, 37075 Göttingen, Germany; Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Stefan Jakobs
- Department of NanoBiophotonics, Mitochondrial Structure and Dynamics Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg, 11 37077 Göttingen, Germany; Clinic for Neurology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; Department of Clinical Chemistry, Bioanalytics, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany; Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Markus Deckers
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
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125
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Yan C, Duanmu X, Zeng L, Liu B, Song Z. Mitochondrial DNA: Distribution, Mutations, and Elimination. Cells 2019; 8:E379. [PMID: 31027297 PMCID: PMC6523345 DOI: 10.3390/cells8040379] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 04/17/2019] [Accepted: 04/20/2019] [Indexed: 12/21/2022] Open
Abstract
Mitochondrion harbors its own DNA (mtDNA), which encodes many critical proteins for the assembly and activity of mitochondrial respiratory complexes. mtDNA is packed by many proteins to form a nucleoid that uniformly distributes within the mitochondrial matrix, which is essential for mitochondrial functions. Defects or mutations of mtDNA result in a range of diseases. Damaged mtDNA could be eliminated by mitophagy, and all paternal mtDNA are degraded by endonuclease G or mitophagy during fertilization. In this review, we describe the role and mechanism of mtDNA distribution and elimination. In particular, we focus on the regulation of paternal mtDNA elimination in the process of fertilization.
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Affiliation(s)
- Chaojun Yan
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Xiaoying Duanmu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Ling Zeng
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Bing Liu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Zhiyin Song
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
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126
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Subramanian K, Jochem A, Le Vasseur M, Lewis S, Paulson BR, Reddy TR, Russell JD, Coon JJ, Pagliarini DJ, Nunnari J. Coenzyme Q biosynthetic proteins assemble in a substrate-dependent manner into domains at ER-mitochondria contacts. J Cell Biol 2019; 218:1353-1369. [PMID: 30674579 PMCID: PMC6446851 DOI: 10.1083/jcb.201808044] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 12/05/2018] [Accepted: 01/10/2019] [Indexed: 12/30/2022] Open
Abstract
Coenzyme Q (CoQ) lipids are ancient electron carriers that, in eukaryotes, function in the mitochondrial respiratory chain. In mitochondria, CoQ lipids are built by an inner membrane-associated, multicomponent, biosynthetic pathway via successive steps of isoprenyl tail polymerization, 4-hydroxybenzoate head-to-tail attachment, and head modification, resulting in the production of CoQ. In yeast, we discovered that head-modifying CoQ pathway components selectively colocalize to multiple resolvable domains in vivo, representing supramolecular assemblies. In cells engineered with conditional ON or OFF CoQ pathways, domains were strictly correlated with CoQ production and substrate flux, respectively, indicating that CoQ lipid intermediates are required for domain formation. Mitochondrial CoQ domains were also observed in human cells, underscoring their conserved functional importance. CoQ domains within cells were highly enriched adjacent to ER-mitochondria contact sites. Together, our data suggest that CoQ domains function to facilitate substrate accessibility for processive and efficient CoQ production and distribution in cells.
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Affiliation(s)
- Kelly Subramanian
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA
| | - Adam Jochem
- Morgridge Institute for Research, Madison, WI
| | - Maxence Le Vasseur
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA
| | - Samantha Lewis
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA
| | | | | | - Jason D Russell
- Morgridge Institute for Research, Madison, WI
- Genome Center of Wisconsin, Madison, WI
| | - Joshua J Coon
- Morgridge Institute for Research, Madison, WI
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI
- Genome Center of Wisconsin, Madison, WI
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI
| | - David J Pagliarini
- Morgridge Institute for Research, Madison, WI
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI
| | - Jodi Nunnari
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA
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127
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Varghese M, Kimler VA, Ghazi FR, Rathore GK, Perkins GA, Ellisman MH, Granneman JG. Adipocyte lipolysis affects Perilipin 5 and cristae organization at the cardiac lipid droplet-mitochondrial interface. Sci Rep 2019; 9:4734. [PMID: 30894648 PMCID: PMC6426865 DOI: 10.1038/s41598-019-41329-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 03/04/2019] [Indexed: 12/14/2022] Open
Abstract
This study investigated the effects of elevated fatty acid (FA) supply from adipose tissue on the ultrastructure of cardiac lipid droplets (LDs) and the expression and organization of LD scaffold proteins perilipin-2 (PLIN2) and perilipin-5 (PLIN5). Stimulation of adipocyte lipolysis by fasting (24 h) or β3-adrenergic receptor activation by CL316, 243 (CL) increased cardiac triacylglycerol (TAG) levels and LD size, whereas CL treatment also increased LD number. LDs were tightly associated with mitochondria, which was maintained during LD expansion. Electron tomography (ET) studies revealed continuity of LD and smooth endoplasmic reticulum (SER), suggesting interconnections among LDs. Under fed ad libitum conditions, the cristae of mitochondria that apposed LD were mostly organized perpendicularly to the tangent of the LD surface. Fasting significantly reduced, whereas CL treatment greatly increased, the perpendicular alignment of mitochondrial cristae. Fasting and CL treatment strongly upregulated PLIN5 protein and PLIN2 to a lesser extent. Immunofluorescence and immuno-electron microscopy demonstrated strong targeting of PLIN5 to the cardiac LD-mitochondrial interface, but not to the mitochondrial matrix. CL treatment augmented PLIN5 targeting to the LD-mitochondrial interface, whereas PLIN2 was not significantly affected. Together, our results support the concept that the interface between LD and cardiac mitochondria represents an organized and dynamic "metabolic synapse" that is highly responsive to FA trafficking.
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Affiliation(s)
- Mita Varghese
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Victoria A Kimler
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Fariha R Ghazi
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Gurnoor K Rathore
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Guy A Perkins
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, 92093, USA
| | - James G Granneman
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
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128
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Alavi MV. Targeted OMA1 therapies for cancer. Int J Cancer 2019; 145:2330-2341. [PMID: 30714136 DOI: 10.1002/ijc.32177] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 01/20/2019] [Accepted: 01/23/2019] [Indexed: 12/12/2022]
Abstract
The mitochondrial inner membrane proteins OMA1 and OPA1 belong to the BAX/BAK1-dependent apoptotic signaling pathway, which can be regulated by tumor protein p53 and the prohibitins PHB and PHB2 in the context of neoplastic disease. For the most part these proteins have been studied separate from each other. Here, I argue that the OMA1 mechanism of action represents the missing link between p53 and cytochrome c release. The mitochondrial fusion protein OPA1 is cleaved by OMA1 in a stress-dependent manner generating S-OPA1. Excessive S-OPA1 can facilitate outer membrane permeabilization upon BAX/BAK1 activation through its membrane shaping properties. p53 helps outer membrane permeabilization in a 2-step process. First, cytosolic p53 activates BAX/BAK1 at the mitochondrial surface. Then, in a second step, p53 binds to prohibitin thereby releasing the restraint on OMA1. This activates OMA1, which cleaves OPA1 and promotes cytochrome c release. Clearly, OMA1 and OPA1 are not root causes for cancer. Yet many cancer cells rely on this pathway for survival, which can explain why loss of p53 function promotes tumor growth and confers resistance to chemotherapies.
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129
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Meurs KM, Friedenberg SG, Olby NJ, Condit J, Weidman J, Rosenthal S, Shelton GD. A QIL1 Variant Associated with Ventricular Arrhythmias and Sudden Cardiac Death in the Juvenile Rhodesian Ridgeback Dog. Genes (Basel) 2019; 10:E168. [PMID: 30795627 PMCID: PMC6409531 DOI: 10.3390/genes10020168] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/09/2019] [Accepted: 02/14/2019] [Indexed: 12/22/2022] Open
Abstract
The QIl1 gene produces a component of the Mitochondrial Contact Site and Cristae Organizing System that forms and stabilizes mitochondrial cristae junctions and is important in cellular energy production. We previously reported a family of Rhodesian Ridgebacks with cardiac arrhythmias and sudden cardiac death. Here, we performed whole genome sequencing on a trio from the family. Variant calling was performed using a standardized bioinformatics approach. Variants were filtered against variants from 247 dogs of 43 different breeds. High impact variants were validated against additional affected and unaffected dogs. A single missense G/A variant in the QIL1 gene was associated with the cardiac arrhythmia (p < 0.0001). The variant was predicted to change the amino acid from conserved Glycine to Serine and to be deleterious. Ultrastructural analysis of the biceps femoris muscle from an affected dog revealed hyperplastic mitochondria, cristae rearrangement, electron dense inclusions and lipid bodies. We identified a variant in the Q1l1 gene resulting in a mitochondrial cardiomyopathy characterized by cristae abnormalities and cardiac arrhythmias in a canine model. This natural animal model of mitochondrial cardiomyopathy provides a large animal model with which to study the development and progression of disease as well as genotypic phenotypic relationships.
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Affiliation(s)
- Kathryn M Meurs
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA.
| | - Steven G Friedenberg
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA.
| | - Natasha J Olby
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA.
| | - Julia Condit
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA.
| | - Jess Weidman
- CVCA at Chesapeake Veterinary Referral Center, 808 Bestgate Road, Annapolis, MD 21401, USA.
| | - Steve Rosenthal
- CVCA at Chesapeake Veterinary Referral Center, 808 Bestgate Road, Annapolis, MD 21401, USA.
| | - G Diane Shelton
- Department of Pathology, University of California San Diego, La Jolla, CA 92093, USA.
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130
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Ueda E, Tamura Y, Sakaue H, Kawano S, Kakuta C, Matsumoto S, Endo T. Myristoyl group-aided protein import into the mitochondrial intermembrane space. Sci Rep 2019; 9:1185. [PMID: 30718713 PMCID: PMC6362269 DOI: 10.1038/s41598-018-38016-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 12/12/2018] [Indexed: 12/20/2022] Open
Abstract
The MICOS complex mediates formation of the crista junctions in mitochondria. Here we analyzed the mitochondrial import pathways for the six yeast MICOS subunits as a step toward understanding of the assembly mechanisms of the MICOS complex. Mic10, Mic12, Mic26, Mic27, and Mic60 used the presequence pathway to reach the intermembrane space (IMS). In contrast, Mic19 took the TIM40/MIA pathway, through its CHCH domain, to reach the IMS. Unlike canonical TIM40/MIA substrates, presence of the N-terminal unfolded DUF domain impaired the import efficiency of Mic19, yet N-terminal myristoylation of Mic19 circumvented this effect. The myristoyl group of Mic19 binds to Tom20 of the TOM complex as well as the outer membrane, which may lead to "entropy pushing" of the DUF domain followed by the CHCH domain of Mic19 into the import channel, thereby achieving efficient import.
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Affiliation(s)
- Eri Ueda
- Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, 464-8602, Japan
- Department of Biological Science, Graduate School of Science, Osaka University, 1-1 machikaneyama-cho, Toyonaka, 560-0043, Osaka, Japan
| | - Yasushi Tamura
- Department of Material and Biological Chemistry, Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata, 990-8560, Japan
| | - Haruka Sakaue
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
- Research Center for Protein Dynamics, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
| | - Shin Kawano
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
- Research Center for Protein Dynamics, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
| | - Chika Kakuta
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
| | - Shunsuke Matsumoto
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
- Research Center for Protein Dynamics, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan
| | - Toshiya Endo
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan.
- Research Center for Protein Dynamics, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto, 603-8555, Japan.
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131
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Abstract
Cell-to-cell heterogeneity drives a range of (patho)physiologically important phenomena, such as cell fate and chemotherapeutic resistance. The role of metabolism, and particularly of mitochondria, is increasingly being recognized as an important explanatory factor in cell-to-cell heterogeneity. Most eukaryotic cells possess a population of mitochondria, in the sense that mitochondrial DNA (mtDNA) is held in multiple copies per cell, where the sequence of each molecule can vary. Hence, intra-cellular mitochondrial heterogeneity is possible, which can induce inter-cellular mitochondrial heterogeneity, and may drive aspects of cellular noise. In this review, we discuss sources of mitochondrial heterogeneity (variations between mitochondria in the same cell, and mitochondrial variations between supposedly identical cells) from both genetic and non-genetic perspectives, and mitochondrial genotype-phenotype links. We discuss the apparent homeostasis of mtDNA copy number, the observation of pervasive intra-cellular mtDNA mutation (which is termed "microheteroplasmy"), and developments in the understanding of inter-cellular mtDNA mutation ("macroheteroplasmy"). We point to the relationship between mitochondrial supercomplexes, cristal structure, pH, and cardiolipin as a potential amplifier of the mitochondrial genotype-phenotype link. We also discuss mitochondrial membrane potential and networks as sources of mitochondrial heterogeneity, and their influence upon the mitochondrial genome. Finally, we revisit the idea of mitochondrial complementation as a means of dampening mitochondrial genotype-phenotype links in light of recent experimental developments. The diverse sources of mitochondrial heterogeneity, as well as their increasingly recognized role in contributing to cellular heterogeneity, highlights the need for future single-cell mitochondrial measurements in the context of cellular noise studies.
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Affiliation(s)
- Juvid Aryaman
- Department of Mathematics, Imperial College London, London, United Kingdom
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Iain G. Johnston
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
- EPSRC Centre for the Mathematics of Precision Healthcare, Imperial College London, London, United Kingdom
| | - Nick S. Jones
- Department of Mathematics, Imperial College London, London, United Kingdom
- EPSRC Centre for the Mathematics of Precision Healthcare, Imperial College London, London, United Kingdom
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132
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Expression of OPA1 and Mic60 genes and their association with mitochondrial cristae morphology in Tibetan sheep. Cell Tissue Res 2019; 376:273-279. [DOI: 10.1007/s00441-018-2975-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 11/29/2018] [Indexed: 10/27/2022]
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133
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Wang L, Yan Z, Vihinen H, Eriksson O, Wang W, Soliymani R, Lu Y, Xue Y, Jokitalo E, Li J, Zhao H. FAM92A1 is a BAR domain protein required for mitochondrial ultrastructure and function. J Cell Biol 2018; 218:97-111. [PMID: 30404948 PMCID: PMC6314547 DOI: 10.1083/jcb.201806191] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/31/2018] [Accepted: 10/17/2018] [Indexed: 01/14/2023] Open
Abstract
Mitochondrial function is closely linked to its dynamic membrane ultrastructure. The mitochondrial inner membrane (MIM) can form extensive membrane invaginations known as cristae, which contain the respiratory chain and ATP synthase for oxidative phosphorylation. The molecular mechanisms regulating mitochondrial ultrastructure remain poorly understood. The Bin-Amphiphysin-Rvs (BAR) domain proteins are central regulators of diverse cellular processes related to membrane remodeling and dynamics. Whether BAR domain proteins are involved in sculpting membranes in specific submitochondrial compartments is largely unknown. In this study, we report FAM92A1 as a novel BAR domain protein localizes to the matrix side of the MIM. Loss of FAM92A1 caused a severe disruption to mitochondrial morphology and ultrastructure, impairing organelle bioenergetics. Furthermore, FAM92A1 displayed a membrane-remodeling activity in vitro, inducing a high degree of membrane curvature. Collectively, our findings uncover a role for a BAR domain protein as a critical organizer of the mitochondrial ultrastructure that is indispensable for mitochondrial function.
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Affiliation(s)
- Liang Wang
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Ziyi Yan
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Helena Vihinen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Ove Eriksson
- Biochemistry/Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Weihuan Wang
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland.,College of Life Sciences, Northwest A&F University, Yangling, China
| | - Rabah Soliymani
- Meilahti Clinical Proteomics Core Facility, HiLIFE, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Yao Lu
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Yaxin Xue
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Eija Jokitalo
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Jing Li
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Hongxia Zhao
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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134
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Kaurov I, Vancová M, Schimanski B, Cadena LR, Heller J, Bílý T, Potěšil D, Eichenberger C, Bruce H, Oeljeklaus S, Warscheid B, Zdráhal Z, Schneider A, Lukeš J, Hashimi H. The Diverged Trypanosome MICOS Complex as a Hub for Mitochondrial Cristae Shaping and Protein Import. Curr Biol 2018; 28:3393-3407.e5. [PMID: 30415698 DOI: 10.1016/j.cub.2018.09.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/02/2018] [Accepted: 09/04/2018] [Indexed: 12/20/2022]
Abstract
The mitochondrial contact site and cristae organization system (MICOS) is a multiprotein complex responsible for cristae formation. Even though cristae are found in all mitochondria capable of oxidative phosphorylation, only Mic10 and Mic60 appear to be conserved throughout eukaryotes. The remaining 4 or 5 known MICOS subunits are specific to the supergroup Opisthokonta, which includes yeast and mammals that are the only organisms in which this complex has been analyzed experimentally. We have isolated the MICOS from Trypanosoma brucei, a member of the supergroup Excavata that is profoundly diverged from opisthokonts. We show that it is required for the maintenance of the unique discoidal cristae that typify excavates, such as euglenids and kinetoplastids, the latter of which include trypanosomes. The trypanosome MICOS consists of 9 subunits, most of which are essential for normal growth. Unlike in opisthokonts, it contains two distinct Mic10 orthologs and an unconventional putative Mic60 that lacks a mitofilin domain. Interestingly, one of the essential trypanosomatid-specific MICOS subunits called TbMic20 is a thioredoxin-like protein that appears to be involved in import of intermembrane space proteins, including respiratory chain complex assembly factors. This result points to trypanosome MICOS coordinating cristae shaping and population of its membrane with proteins involved in respiration, the latter via the catalytic activity of TbMic20. Thus, trypanosome MICOS allows us to define which of its features are conserved in all eukaryotes and decipher those that represent lineage-specific adaptations.
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Affiliation(s)
- Iosif Kaurov
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Marie Vancová
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Bernd Schimanski
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Lawrence Rudy Cadena
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Jiří Heller
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Tomáš Bílý
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - David Potěšil
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic
| | - Claudia Eichenberger
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Hannah Bruce
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Silke Oeljeklaus
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, 79104 Freiburg, Germany
| | - Bettina Warscheid
- Faculty of Biology, Biochemistry and Functional Proteomics, Institute of Biology II, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic
| | - André Schneider
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Julius Lukeš
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Hassan Hashimi
- Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic.
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135
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Abstract
Mitochondria contain their own genome that encodes for a small number of proteins, while the vast majority of mitochondrial proteins is produced on cytosolic ribosomes. The formation of respiratory chain complexes depends on the coordinated biogenesis of mitochondrially encoded and nuclear-encoded subunits. In this review, we describe pathways that adjust mitochondrial protein synthesis and import of nuclear-encoded subunits to the assembly of respiratory chain complexes. Furthermore, we outline how defects in protein import into mitochondria affect nuclear gene expression to maintain protein homeostasis under physiological and stress conditions.
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Affiliation(s)
- Chantal Priesnitz
- Institute of Biochemistry and Molecular Biology, Center for Biochemistry and Molecular Cell Research (ZBMZ), Faculty of Medicine, University of Freiburg, D-79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, D-79104 Freiburg, Germany
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, Center for Biochemistry and Molecular Cell Research (ZBMZ), Faculty of Medicine, University of Freiburg, D-79104 Freiburg, Germany
- BIOSS Centre for Biological Signaling Studies, University of Freiburg, D-79104 Freiburg, Germany
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136
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Habich M, Salscheider SL, Riemer J. Cysteine residues in mitochondrial intermembrane space proteins: more than just import. Br J Pharmacol 2018; 176:514-531. [PMID: 30129023 DOI: 10.1111/bph.14480] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 06/20/2018] [Accepted: 06/26/2018] [Indexed: 12/13/2022] Open
Abstract
The intermembrane space (IMS) is a very small mitochondrial sub-compartment with critical relevance for many cellular processes. IMS proteins fulfil important functions in transport of proteins, lipids, metabolites and metal ions, in signalling, in metabolism and in defining the mitochondrial ultrastructure. Our understanding of the IMS proteome has become increasingly refined although we still lack information on the identity and function of many of its proteins. One characteristic of many IMS proteins are conserved cysteines. Different post-translational modifications of these cysteine residues can have critical roles in protein function, localization and/or stability. The close localization to different ROS-producing enzyme systems, a dedicated machinery for oxidative protein folding, and a unique equipment with antioxidative systems, render the careful balancing of the redox and modification states of the cysteine residues, a major challenge in the IMS. In this review, we discuss different functions of human IMS proteins, the involvement of cysteine residues in these functions, the consequences of cysteine modifications and the consequences of cysteine mutations or defects in the machinery for disulfide bond formation in terms of human health. LINKED ARTICLES: This article is part of a themed section on Chemical Biology of Reactive Sulfur Species. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.4/issuetoc.
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Affiliation(s)
- Markus Habich
- Department of Chemistry, Institute of Biochemistry, Redox Biochemistry, University of Cologne, Cologne, Germany
| | - Silja Lucia Salscheider
- Department of Chemistry, Institute of Biochemistry, Redox Biochemistry, University of Cologne, Cologne, Germany
| | - Jan Riemer
- Department of Chemistry, Institute of Biochemistry, Redox Biochemistry, University of Cologne, Cologne, Germany
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137
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Novel Approaches To Kill Toxoplasma gondii by Exploiting the Uncontrolled Uptake of Unsaturated Fatty Acids and Vulnerability to Lipid Storage Inhibition of the Parasite. Antimicrob Agents Chemother 2018; 62:AAC.00347-18. [PMID: 30061287 DOI: 10.1128/aac.00347-18] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/21/2018] [Indexed: 12/17/2022] Open
Abstract
Toxoplasma gondii, an obligate intracellular parasite replicating in mammalian cells within a parasitophorous vacuole (PV), is an avid scavenger of lipids retrieved from the host cell. Following lipid uptake, this parasite stores excess lipids in lipid droplets (LD). Here, we examined the lipid storage capacities of Toxoplasma upon supplementation of the culture medium with various fatty acids at physiological concentrations. Supplemental unsaturated fatty acids (oleate [OA], palmitoleate, linoleate) accumulate in large LD and impair parasite replication, whereas saturated fatty acids (palmitate, stearate) neither stimulate LD formation nor impact growth. Examination of parasite growth defects with 0.4 mM OA revealed massive lipid deposits outside LD, indicating enzymatic inadequacies for storing neutral lipids in LD in response to the copious salvage of OA. Toxoplasma exposure to 0.5 mM OA led to irreversible growth arrest and lipid-induced damage, confirming a major disconnect between fatty acid uptake and the parasite's cellular lipid requirements. The importance of neutral lipid synthesis and storage to avoid lipotoxicity was further highlighted by the selective vulnerability of Toxoplasma, both the proliferative and the encysted forms, to subtoxic concentrations of the acyl coenzyme A:diacylglycerol acyltransferase 1 (DGAT1) pharmacological inhibitor T863. T863-treated parasites did not form LD but instead built up large membranous structures within the cytoplasm, which suggests improper channeling and management of the excess lipid. Dual addition of OA and T863 to infected cells intensified the deterioration of the parasite. Overall, our data pinpoint Toxoplasma DGAT as a promising drug target for the treatment of toxoplasmosis that would not incur the risk of toxicity for mammalian cells.
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138
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Nicholls TJ, Gustafsson CM. Separating and Segregating the Human Mitochondrial Genome. Trends Biochem Sci 2018; 43:869-881. [PMID: 30224181 DOI: 10.1016/j.tibs.2018.08.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 12/17/2022]
Abstract
Cells contain thousands of copies of the mitochondrial genome. These genomes are distributed within the tubular mitochondrial network, which is itself spread across the cytosol of the cell. Mitochondrial DNA (mtDNA) replication occurs throughout the cell cycle and ensures that cells maintain a sufficient number of mtDNA copies. At replication termination the genomes must be resolved and segregated within the mitochondrial network. Defects in mtDNA replication and segregation are a cause of human mitochondrial disease associated with failure of cellular energy production. This review focuses upon recent developments on how mitochondrial genomes are physically separated at the end of DNA replication, and how these genomes are subsequently segregated and distributed around the mitochondrial network.
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Affiliation(s)
- Thomas J Nicholls
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, SE-405 30 Gothenburg, Sweden.
| | - Claes M Gustafsson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, SE-405 30 Gothenburg, Sweden
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139
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Könnel A, Bugaeva W, Gügel IL, Philippar K. BANFF: bending of bilayer membranes by amphiphilic α-helices is necessary for form and function of organelles 1. Biochem Cell Biol 2018; 97:243-256. [PMID: 30208283 DOI: 10.1139/bcb-2018-0150] [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: 12/26/2022] Open
Abstract
By binding to and inserting into the lipid bilayer, amphiphilic α-helices of proteins are involved in the curvature of biological membranes in all organisms. In particular, they are involved in establishing the complex membrane architecture of intracellular organelles like the endoplasmatic reticulum, Golgi apparatus, mitochondria, and chloroplasts. Thus, amphiphilic α-helices are essential for maintenance of cellular metabolism and fitness of organisms. Here we focus on the structure and function of membrane-intrinsic proteins, which are involved in membrane curvature by amphiphilic α-helices, in mitochondria and chloroplasts of the eukaryotic model organisms yeast and Arabidopsis thaliana. Further, we propose a model for transport of fatty acids and lipid compounds across the envelope of chloroplasts in which amphiphilic α-helices might play a role.
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Affiliation(s)
- Anne Könnel
- a Center for Human- and Molecular Biology (ZHMB) - Plant Biology, Saarland University, Campus A 2.4, 66123 Saarbrücken, Germany
| | - Wassilina Bugaeva
- a Center for Human- and Molecular Biology (ZHMB) - Plant Biology, Saarland University, Campus A 2.4, 66123 Saarbrücken, Germany
| | - Irene L Gügel
- b Department of Biology I - Botany, Ludwig-Maximilians University München, Großhaderner-Str. 2, 82152 Planegg-Martinsried, Germany
| | - Katrin Philippar
- a Center for Human- and Molecular Biology (ZHMB) - Plant Biology, Saarland University, Campus A 2.4, 66123 Saarbrücken, Germany
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140
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Herwaldt EJ, Rivett ED, White AJ, Hegg EL. Cox15 interacts with the cytochrome bc 1 dimer within respiratory supercomplexes as well as in the absence of cytochrome c oxidase. J Biol Chem 2018; 293:16426-16439. [PMID: 30181213 DOI: 10.1074/jbc.ra118.002496] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 08/15/2018] [Indexed: 11/06/2022] Open
Abstract
The heme a molecule is an obligatory cofactor in the terminal enzyme complex of the electron transport chain, cytochrome c oxidase. Heme a is synthesized from heme o by a multi-spanning inner membrane protein, heme a synthase (Cox15 in the yeast Saccharomyces cerevisiae). The insertion of heme a is critical for cytochrome c oxidase function and assembly, but this process has not been fully elucidated. To improve our understanding of heme a insertion into cytochrome c oxidase, here we investigated the protein-protein interactions that involve Cox15 in S. cerevisiae In addition to observing Cox15 in homooligomeric complexes, we found that a portion of Cox15 also associates with the mitochondrial respiratory supercomplexes. When supercomplex formation was abolished, as in the case of stalled cytochrome bc 1 or cytochrome c oxidase assembly, Cox15 maintained an interaction with select proteins from both respiratory complexes. In the case of stalled cytochrome bc 1 assembly, Cox15 interacted with the late-assembling cytochrome c oxidase subunit, Cox13. When cytochrome c oxidase assembly was stalled, Cox15 unexpectedly maintained its interaction with the cytochrome bc 1 protein, Cor1. Our results indicate that Cox15 and Cor1 continue to interact in the cytochrome bc 1 dimer even in the absence of supercomplexes or when the supercomplexes are destabilized. These findings reveal that Cox15 not only associates with respiratory supercomplexes, but also interacts with the cytochrome bc 1 dimer even in the absence of cytochrome c oxidase.
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Affiliation(s)
- Emily J Herwaldt
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Elise D Rivett
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Antoineen J White
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Eric L Hegg
- From the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
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141
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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: 101] [Impact Index Per Article: 16.8] [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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142
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Plant mitochondrial protein import: the ins and outs. Biochem J 2018; 475:2191-2208. [PMID: 30018142 DOI: 10.1042/bcj20170521] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 06/19/2018] [Accepted: 06/21/2018] [Indexed: 01/29/2023]
Abstract
The majority of the mitochondrial proteome, required to fulfil its diverse range of functions, is cytosolically synthesised and translocated via specialised machinery. The dedicated translocases, receptors, and associated proteins have been characterised in great detail in yeast over the last several decades, yet many of the mechanisms that regulate these processes in higher eukaryotes are still unknown. In this review, we highlight the current knowledge of mitochondrial protein import in plants. Despite the fact that the mechanisms of mitochondrial protein import have remained conserved across species, many unique features have arisen in plants to encompass the developmental, tissue-specific, and stress-responsive regulation in planta. An understanding of unique features and mechanisms in plants provides us with a unique insight into the regulation of mitochondrial biogenesis in higher eukaryotes.
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143
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Peralta S, Goffart S, Williams SL, Diaz F, Garcia S, Nissanka N, Area-Gomez E, Pohjoismäki J, Moraes CT. ATAD3 controls mitochondrial cristae structure in mouse muscle, influencing mtDNA replication and cholesterol levels. J Cell Sci 2018; 131:jcs217075. [PMID: 29898916 PMCID: PMC6051345 DOI: 10.1242/jcs.217075] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/30/2018] [Indexed: 01/01/2023] Open
Abstract
Mutations in the mitochondrial inner membrane ATPase ATAD3A result in neurological syndromes in humans. In mice, the ubiquitous disruption of Atad3 (also known as Atad3a) was embryonic lethal, but a skeletal muscle-specific conditional knockout (KO) was viable. At birth, ATAD3 muscle KO mice had normal weight, but from 2 months onwards they showed progressive motor-impaired coordination and weakness. Loss of ATAD3 caused early and severe mitochondrial structural abnormalities, mitochondrial proliferation and muscle atrophy. There was dramatic reduction in mitochondrial cristae junctions and overall cristae morphology. The lack of mitochondrial cristae was accompanied by a reduction in high molecular weight mitochondrial contact site and cristae organizing system (MICOS) complexes, and to a lesser extent in OPA1. Moreover, muscles lacking ATAD3 showed altered cholesterol metabolism, accumulation of mitochondrial DNA (mtDNA) replication intermediates, progressive mtDNA depletion and deletions. Unexpectedly, decreases in the levels of some OXPHOS components occurred after cristae destabilization, indicating that ATAD3 is not crucial for mitochondrial translation, as previously suggested. Our results show a critical early role of ATAD3 in regulating mitochondrial inner membrane structure, leading to secondary defects in mtDNA replication and complex V and cholesterol levels in postmitotic tissue.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Susana Peralta
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Steffi Goffart
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu 80101, Finland
| | - Sion L Williams
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Francisca Diaz
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Sofia Garcia
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Nadee Nissanka
- Neuroscience Graduate Program, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Estela Area-Gomez
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
| | - Jaakko Pohjoismäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu 80101, Finland
| | - Carlos T Moraes
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- Neuroscience Graduate Program, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- Department of Cell Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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144
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Rampelt H, Wollweber F, Gerke C, de Boer R, van der Klei IJ, Bohnert M, Pfanner N, van der Laan M. Assembly of the Mitochondrial Cristae Organizer Mic10 Is Regulated by Mic26–Mic27 Antagonism and Cardiolipin. J Mol Biol 2018; 430:1883-1890. [DOI: 10.1016/j.jmb.2018.04.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/20/2018] [Accepted: 04/27/2018] [Indexed: 01/05/2023]
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145
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Stoldt S, Wenzel D, Kehrein K, Riedel D, Ott M, Jakobs S. Spatial orchestration of mitochondrial translation and OXPHOS complex assembly. Nat Cell Biol 2018; 20:528-534. [PMID: 29662179 DOI: 10.1038/s41556-018-0090-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 03/20/2018] [Indexed: 12/11/2022]
Abstract
Oxidative phosphorylation (OXPHOS) is vital for the regeneration of the vast majority of ATP in eukaryotic cells 1 . OXPHOS is carried out by large multi-subunit protein complexes in the cristae membranes, which are invaginations of the mitochondrial inner membrane. The OXPHOS complexes are a mix of subunits encoded in the nuclear and mitochondrial genomes. Thus, the assembly of these dual-origin complexes is an enormous logistical challenge for the cell. Using super-resolution microscopy (nanoscopy) and quantitative cryo-immunogold electron microscopy, we determined where specific transcripts are translated and where distinct assembly steps of the dual-origin complexes in the yeast Saccharomyces cerevisiae occur. Our data indicate that the mitochondrially encoded proteins of complex III and complex IV are preferentially inserted in different sites of the inner membrane than those of complex V. We further demonstrate that the early, but not the late, assembly steps of complex III and complex IV occur preferentially in the inner boundary membrane. By contrast, all steps of complex V assembly occur mainly in the cristae membranes. Thus, OXPHOS complex assembly is spatially well orchestrated, probably representing an unappreciated regulatory layer in mitochondrial biogenesis.
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Affiliation(s)
- Stefan Stoldt
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Dirk Wenzel
- Laboratory of Electron Microscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Kirsten Kehrein
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Dietmar Riedel
- Laboratory of Electron Microscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Martin Ott
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Stefan Jakobs
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany. .,Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.
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146
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Kudryavtseva AV, Krasnov GS, Dmitriev AA, Alekseev BY, Kardymon OL, Sadritdinova AF, Fedorova MS, Pokrovsky AV, Melnikova NV, Kaprin AD, Moskalev AA, Snezhkina AV. Mitochondrial dysfunction and oxidative stress in aging and cancer. Oncotarget 2018; 7:44879-44905. [PMID: 27270647 PMCID: PMC5216692 DOI: 10.18632/oncotarget.9821] [Citation(s) in RCA: 345] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/28/2016] [Indexed: 12/16/2022] Open
Abstract
Aging and cancer are the most important issues to research. The population in the world is growing older, and the incidence of cancer increases with age. There is no doubt about the linkage between aging and cancer. However, the molecular mechanisms underlying this association are still unknown. Several lines of evidence suggest that the oxidative stress as a cause and/or consequence of the mitochondrial dysfunction is one of the main drivers of these processes. Increasing ROS levels and products of the oxidative stress, which occur in aging and age-related disorders, were also found in cancer. This review focuses on the similarities between ageing-associated and cancer-associated oxidative stress and mitochondrial dysfunction as their common phenotype.
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Affiliation(s)
- Anna V Kudryavtseva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.,National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow, Russia
| | - George S Krasnov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Alexey A Dmitriev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Boris Y Alekseev
- National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Olga L Kardymon
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Asiya F Sadritdinova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.,National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Maria S Fedorova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Nataliya V Melnikova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Andrey D Kaprin
- National Medical Research Radiological Center, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Alexey A Moskalev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny, Russia
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147
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Casella S, Huang F, Mason D, Zhao GY, Johnson GN, Mullineaux CW, Liu LN. Dissecting the Native Architecture and Dynamics of Cyanobacterial Photosynthetic Machinery. MOLECULAR PLANT 2017; 10:1434-1448. [PMID: 29017828 PMCID: PMC5683893 DOI: 10.1016/j.molp.2017.09.019] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 09/25/2017] [Accepted: 09/29/2017] [Indexed: 05/18/2023]
Abstract
The structural dynamics and flexibility of cell membranes play fundamental roles in the functions of the cells, i.e., signaling, energy transduction, and physiological adaptation. The cyanobacterial thylakoid membrane represents a model membrane that can conduct both oxygenic photosynthesis and respiration simultaneously. In this study, we conducted direct visualization of the global organization and mobility of photosynthetic complexes in thylakoid membranes from a model cyanobacterium, Synechococcus elongatus PCC 7942, using high-resolution atomic force, confocal, and total internal reflection fluorescence microscopy. We visualized the native arrangement and dense packing of photosystem I (PSI), photosystem II (PSII), and cytochrome (Cyt) b6f within thylakoid membranes at the molecular level. Furthermore, we functionally tagged PSI, PSII, Cyt b6f, and ATP synthase individually with fluorescent proteins, and revealed the heterogeneous distribution of these four photosynthetic complexes and determined their dynamic features within the crowding membrane environment using live-cell fluorescence imaging. We characterized red light-induced clustering localization and adjustable diffusion of photosynthetic complexes in thylakoid membranes, representative of the reorganization of photosynthetic apparatus in response to environmental changes. Understanding the organization and dynamics of photosynthetic membranes is essential for rational design and construction of artificial photosynthetic systems to underpin bioenergy development. Knowledge of cyanobacterial thylakoid membranes could also be extended to other cell membranes, such as chloroplast and mitochondrial membranes.
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Affiliation(s)
- Selene Casella
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK
| | - Fang Huang
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK
| | - David Mason
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK; Centre for Cell Imaging, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK
| | - Guo-Yan Zhao
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK; College of Life Science, Shandong Normal University, Jinan 250014, P. R. China
| | - Giles N Johnson
- School of Earth and Environmental Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Conrad W Mullineaux
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Lu-Ning Liu
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK.
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148
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Schorr S, van der Laan M. Integrative functions of the mitochondrial contact site and cristae organizing system. Semin Cell Dev Biol 2017; 76:191-200. [PMID: 28923515 DOI: 10.1016/j.semcdb.2017.09.021] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 09/13/2017] [Accepted: 09/14/2017] [Indexed: 12/23/2022]
Abstract
Mitochondria are complex double-membrane-bound organelles of eukaryotic cells that function as energy-converting powerhouses, metabolic factories and signaling centers. The outer membrane controls the exchange of material and information with other cellular compartments. The inner membrane provides an extended, highly folded surface for selective transport and energy-coupling reactions. It can be divided into an inner boundary membrane and tubular or lamellar cristae membranes that accommodate the oxidative phosphorylation units. Outer membrane, inner boundary membrane and cristae come together at crista junctions, where the mitochondrial contact site and cristae organizing system (MICOS) acts as a membrane-shaping and -connecting scaffold. This peculiar architecture is of pivotal importance for multiple mitochondrial functions. Many elaborate studies in the past years have shed light on the subunit composition and organization of MICOS. In this review article, we summarize these insights and then move on to discuss exciting recent discoveries on the integrative functions of MICOS. Multi-faceted connections to other major players of mitochondrial biogenesis and physiology, like the protein import machineries, the oxidative phosphorylation system, carrier proteins and phospholipid biosynthesis enzymes, are currently emerging. Therefore, we propose that MICOS acts as a central hub in mitochondrial membrane architecture and functionality.
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Affiliation(s)
- Stefan Schorr
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Saarland University, School of Medicine, 66421, Homburg, Germany
| | - Martin van der Laan
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Saarland University, School of Medicine, 66421, Homburg, Germany.
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149
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Mun JY, Jung MK, Kim SH, Eom S, Han SS, Lee YM. Ultrastructural Changes in Skeletal Muscle of Infants with Mitochondrial Respiratory Chain Complex I Defects. J Clin Neurol 2017; 13:359-365. [PMID: 28884981 PMCID: PMC5653623 DOI: 10.3988/jcn.2017.13.4.359] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 06/07/2017] [Accepted: 06/07/2017] [Indexed: 12/26/2022] Open
Abstract
Background and Purpose The pathogenesis of mitochondrial disease (MD) involves the disruption of cellular energy metabolism, which results from defects in the mitochondrial respiratory chain complex (MRC). We investigated whether infants with MRC I defects showed ultrastructural changes in skeletal muscle. Methods Twelve infants were enrolled in this study. They were initially evaluated for unexplained neurodegenerative symptoms, myopathies, or other progressive multiorgan involvement, and underwent muscle biopsies when MD was suspected. Muscle tissue samples were subjected to biochemical enzyme assays and observation by transmission electron microscopy. We compared and analyzed the ultrastructure of skeletal muscle tissues obtained from patients with and without MRC I defects. Results Biochemical enzyme assays confirmed the presence of MRC I defects in 7 of the 12 patients. Larger mitochondria, lipid droplets, and fused structures between the outer mitochondrial membrane and lipid droplets were observed in the skeletal muscles of patients with MRC I defects. Conclusions Mitochondrial functional defects in MRC I disrupt certain activities related to adenosine triphosphate synthesis that produce changes in the skeletal muscle. The ultrastructural changes observed in the infants in this study might serve as unique markers for the detection of MD.
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Affiliation(s)
- Ji Young Mun
- Department of Biomedical Laboratory Science, College of Health Sciences, Eulji University, Seongnam, Korea
| | - Min Kyo Jung
- School of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| | - Se Hoon Kim
- Department of Pathology, Yonsei University College of Medicine, Seoul, Korea
| | - Soyong Eom
- Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Sung Sik Han
- School of Life Sciences and Biotechnology, Korea University, Seoul, Korea
| | - Young Mock Lee
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
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150
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De Vos KJ, Hafezparast M. Neurobiology of axonal transport defects in motor neuron diseases: Opportunities for translational research? Neurobiol Dis 2017; 105:283-299. [PMID: 28235672 PMCID: PMC5536153 DOI: 10.1016/j.nbd.2017.02.004] [Citation(s) in RCA: 147] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/26/2017] [Accepted: 02/20/2017] [Indexed: 12/12/2022] Open
Abstract
Intracellular trafficking of cargoes is an essential process to maintain the structure and function of all mammalian cell types, but especially of neurons because of their extreme axon/dendrite polarisation. Axonal transport mediates the movement of cargoes such as proteins, mRNA, lipids, membrane-bound vesicles and organelles that are mostly synthesised in the cell body and in doing so is responsible for their correct spatiotemporal distribution in the axon, for example at specialised sites such as nodes of Ranvier and synaptic terminals. In addition, axonal transport maintains the essential long-distance communication between the cell body and synaptic terminals that allows neurons to react to their surroundings via trafficking of for example signalling endosomes. Axonal transport defects are a common observation in a variety of neurodegenerative diseases, and mutations in components of the axonal transport machinery have unequivocally shown that impaired axonal transport can cause neurodegeneration (reviewed in El-Kadi et al., 2007, De Vos et al., 2008; Millecamps and Julien, 2013). Here we review our current understanding of axonal transport defects and the role they play in motor neuron diseases (MNDs) with a specific focus on the most common form of MND, amyotrophic lateral sclerosis (ALS).
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Affiliation(s)
- Kurt J De Vos
- Sheffield Institute for Translational Neuroscience, Department of Neuroscience, University of Sheffield, Sheffield S10 2HQ, UK.
| | - Majid Hafezparast
- Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK.
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