1
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Ouyang Y, Jeong MY, Cunningham CN, Berg JA, Toshniwal AG, Hughes CE, Seiler K, Van Vranken JG, Cluntun AA, Lam G, Winter JM, Akdogan E, Dove KK, Nowinski SM, West M, Odorizzi G, Gygi SP, Dunn CD, Winge DR, Rutter J. Phosphate starvation signaling increases mitochondrial membrane potential through respiration-independent mechanisms. eLife 2024; 13:e84282. [PMID: 38251707 PMCID: PMC10846858 DOI: 10.7554/elife.84282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/19/2024] [Indexed: 01/23/2024] Open
Abstract
Mitochondrial membrane potential directly powers many critical functions of mitochondria, including ATP production, mitochondrial protein import, and metabolite transport. Its loss is a cardinal feature of aging and mitochondrial diseases, and cells closely monitor membrane potential as an indicator of mitochondrial health. Given its central importance, it is logical that cells would modulate mitochondrial membrane potential in response to demand and environmental cues, but there has been little exploration of this question. We report that loss of the Sit4 protein phosphatase in yeast increases mitochondrial membrane potential, both by inducing the electron transport chain and the phosphate starvation response. Indeed, a similarly elevated mitochondrial membrane potential is also elicited simply by phosphate starvation or by abrogation of the Pho85-dependent phosphate sensing pathway. This enhanced membrane potential is primarily driven by an unexpected activity of the ADP/ATP carrier. We also demonstrate that this connection between phosphate limitation and enhancement of mitochondrial membrane potential is observed in primary and immortalized mammalian cells as well as in Drosophila. These data suggest that mitochondrial membrane potential is subject to environmental stimuli and intracellular signaling regulation and raise the possibility for therapeutic enhancement of mitochondrial function even in defective mitochondria.
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Affiliation(s)
- Yeyun Ouyang
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Mi-Young Jeong
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Corey N Cunningham
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Jordan A Berg
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Ashish G Toshniwal
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Casey E Hughes
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Kristina Seiler
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | | | - Ahmad A Cluntun
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Geanette Lam
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Jacob M Winter
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Emel Akdogan
- Department of Molecular Biology and Genetics, Koç UniversityİstanbulTurkey
| | - Katja K Dove
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Sara M Nowinski
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
| | - Matthew West
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, BoulderBoulderUnited States
| | - Greg Odorizzi
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, BoulderBoulderUnited States
| | - Steven P Gygi
- Department of Cell Biology, Harvard University School of MedicineBostonUnited States
| | - Cory D Dunn
- Department of Molecular Biology and Genetics, Koç UniversityİstanbulTurkey
- Institute of Biotechnology, University of HelsinkiHelsinkiFinland
| | - Dennis R Winge
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
- Department of Medicine, The University of UtahSalt Lake CityUnited States
| | - Jared Rutter
- Department of Biochemistry, The University of UtahSalt Lake CityUnited States
- Howard Hughes Medical Institute, University of UtahSalt Lake CityUnited States
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2
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Magistrati M, Gilea AI, Gerra MC, Baruffini E, Dallabona C. Drug Drop Test: How to Quickly Identify Potential Therapeutic Compounds for Mitochondrial Diseases Using Yeast Saccharomyces cerevisiae. Int J Mol Sci 2023; 24:10696. [PMID: 37445873 DOI: 10.3390/ijms241310696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 06/22/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
Mitochondrial diseases (MDs) refer to a group of clinically and genetically heterogeneous pathologies characterized by defective mitochondrial function and energy production. Unfortunately, there is no effective treatment for most MDs, and current therapeutic management is limited to relieving symptoms. The yeast Saccharomyces cerevisiae has been efficiently used as a model organism to study mitochondria-related disorders thanks to its easy manipulation and well-known mitochondrial biogenesis and metabolism. It has been successfully exploited both to validate alleged pathogenic variants identified in patients and to discover potential beneficial molecules for their treatment. The so-called "drug drop test", a phenotype-based high-throughput screening, especially if coupled with a drug repurposing approach, allows the identification of molecules with high translational potential in a cost-effective and time-saving manner. In addition to drug identification, S. cerevisiae can be used to point out the drug's target or pathway. To date, drug drop tests have been successfully carried out for a variety of disease models, leading to very promising results. The most relevant aspect is that studies on more complex model organisms confirmed the effectiveness of the drugs, strengthening the results obtained in yeast and demonstrating the usefulness of this screening as a novel approach to revealing new therapeutic molecules for MDs.
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Affiliation(s)
- Martina Magistrati
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Alexandru Ionut Gilea
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Maria Carla Gerra
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Enrico Baruffini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
| | - Cristina Dallabona
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy
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3
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Saini M, Julius Ngwa C, Marothia M, Verma P, Ahmad S, Kumari J, Anand S, Vandana V, Goyal B, Chakraborti S, Pandey KC, Garg S, Pati S, Ranganathan A, Pradel G, Singh S. Characterization of Plasmodium falciparum prohibitins as novel targets to block infection in humans by impairing the growth and transmission of the parasite. Biochem Pharmacol 2023; 212:115567. [PMID: 37088154 DOI: 10.1016/j.bcp.2023.115567] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/04/2023] [Accepted: 04/17/2023] [Indexed: 04/25/2023]
Abstract
Prohibitins (PHBs) are highly conserved pleiotropic proteins as they have been shown to mediate key cellular functions. Here, we characterize PHBs encoding putative genes of Plasmodium falciparum by exploiting different orthologous models. We demonstrated that PfPHB1 (PF3D7_0829200) and PfPHB2 (PF3D7_1014700) are expressed in asexual and sexual blood stages of the parasite. Immunostaining indicated these proteins as mitochondrial residents as they were found to be localized as branched structures. We further validated PfPHBs as organellar proteins residing in Plasmodium mitochondria, where they interact with each other. Functional characterization was done in Saccharomyces cerevisiae orthologous model by expressing PfPHB1 and PfPHB2 in cells harboring respective mutants. The PfPHBs functionally complemented the yeast PHB1 and PHB2 mutants, where the proteins were found to be involved in stabilizing the mitochondrial DNA, retaining mitochondrial integrity and rescuing yeast cell growth. Further, Rocaglamide (Roc-A), a known inhibitor of PHBs and anti-cancerous agent, was tested against PfPHBs and as an antimalarial. Roc-A treatment retarded the growth of PHB1, PHB2, and ethidium bromide petite yeast mutants. Moreover, Roc-A inhibited growth of yeast PHBs mutants that were functionally complemented with PfPHBs, validating P. falciparum PHBs as one of the molecular targets for Roc-A. Roc-A treatment led to growth inhibition of artemisinin-sensitive (3D7), artemisinin-resistant (R539T) and chloroquine-resistant (RKL-9) parasites in nanomolar ranges. The compound was able to retard gametocyte and oocyst growth with significant morphological aberrations. Based on our findings, we propose the presence of functional mitochondrial PfPHB1 and PfPHB2 in P. falciparum and their druggability to block parasite growth.
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Affiliation(s)
- Monika Saini
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Delhi NCR, India; Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Aachen, Germany; Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Che Julius Ngwa
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Aachen, Germany
| | - Manisha Marothia
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Pritee Verma
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Shakeel Ahmad
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Jyoti Kumari
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Delhi NCR, India; Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Sakshi Anand
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Vandana Vandana
- ICMR-National Institute of Malaria Research, New Delhi, India
| | - Bharti Goyal
- ICMR-National Institute of Malaria Research, New Delhi, India
| | | | - Kailash C Pandey
- ICMR-National Institute of Malaria Research, New Delhi, India; Academic Council of Scientific and Innovative Research, Faridabad, India
| | - Swati Garg
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Soumya Pati
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Delhi NCR, India
| | - Anand Ranganathan
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Aachen, Germany
| | - Shailja Singh
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Delhi NCR, India; Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India.
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4
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Kabala AM, Binko K, Godard F, Charles C, Dautant A, Baranowska E, Skoczen N, Gombeau K, Bouhier M, Becker HD, Ackerman SH, Steinmetz LM, Tribouillard-Tanvier D, Kucharczyk R, di Rago JP. Assembly-dependent translation of subunits 6 (Atp6) and 9 (Atp9) of ATP synthase in yeast mitochondria. Genetics 2022; 220:iyac007. [PMID: 35100419 PMCID: PMC8893259 DOI: 10.1093/genetics/iyac007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/30/2021] [Indexed: 12/04/2022] Open
Abstract
The yeast mitochondrial ATP synthase is an assembly of 28 subunits of 17 types of which 3 (subunits 6, 8, and 9) are encoded by mitochondrial genes, while the 14 others have a nuclear genetic origin. Within the membrane domain (FO) of this enzyme, the subunit 6 and a ring of 10 identical subunits 9 transport protons across the mitochondrial inner membrane coupled to ATP synthesis in the extra-membrane structure (F1) of ATP synthase. As a result of their dual genetic origin, the ATP synthase subunits are synthesized in the cytosol and inside the mitochondrion. How they are produced in the proper stoichiometry from two different cellular compartments is still poorly understood. The experiments herein reported show that the rate of translation of the subunits 9 and 6 is enhanced in strains with mutations leading to specific defects in the assembly of these proteins. These translation modifications involve assembly intermediates interacting with subunits 6 and 9 within the final enzyme and cis-regulatory sequences that control gene expression in the organelle. In addition to enabling a balanced output of the ATP synthase subunits, these assembly-dependent feedback loops are presumably important to limit the accumulation of harmful assembly intermediates that have the potential to dissipate the mitochondrial membrane electrical potential and the main source of chemical energy of the cell.
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Affiliation(s)
- Anna M Kabala
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Krystyna Binko
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - François Godard
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
| | - Camille Charles
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
| | - Alain Dautant
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
| | - Emilia Baranowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Natalia Skoczen
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Kewin Gombeau
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
| | - Marine Bouhier
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
| | - Hubert D Becker
- UPR ‘Architecture et Réactivité de l’ARN’, CNRS, Institut de Biologie Moléculaire et Cellulaire, Université de Strasbourg, F-67084 Strasbourg Cedex, France
| | - Sharon H Ackerman
- Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, Detroit, MI 48202, USA
| | - Lars M Steinmetz
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
- Stanford Genome Technology Center, Palo Alto, CA 94304, USA
| | | | - Roza Kucharczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 01-224 Warsaw, Poland
| | - Jean-Paul di Rago
- CNRS, IBGC, University of Bordeaux, UMR 5095, F-33000 Bordeaux, France
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5
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Li J, Rinnerthaler M, Hartl J, Weber M, Karl T, Breitenbach-Koller H, Mülleder M, Vowinckel J, Marx H, Sauer M, Mattanovich D, Ata Ö, De S, Greslehner GP, Geltinger F, Burhans B, Grant C, Doronina V, Ralser M, Streubel MK, Grabner C, Jarolim S, Moßhammer C, Gourlay CW, Hasek J, Cullen PJ, Liti G, Ralser M, Breitenbach M. Slow Growth and Increased Spontaneous Mutation Frequency in Respiratory Deficient afo1- Yeast Suppressed by a Dominant Mutation in ATP3. G3 (BETHESDA, MD.) 2020; 10:4637-4648. [PMID: 33093184 PMCID: PMC7718765 DOI: 10.1534/g3.120.401537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/19/2020] [Indexed: 12/26/2022]
Abstract
A yeast deletion mutation in the nuclear-encoded gene, AFO1, which codes for a mitochondrial ribosomal protein, led to slow growth on glucose, the inability to grow on glycerol or ethanol, and loss of mitochondrial DNA and respiration. We noticed that afo1- yeast readily obtains secondary mutations that suppress aspects of this phenotype, including its growth defect. We characterized and identified a dominant missense suppressor mutation in the ATP3 gene. Comparing isogenic slowly growing rho-zero and rapidly growing suppressed afo1- strains under carefully controlled fermentation conditions showed that energy charge was not significantly different between strains and was not causal for the observed growth properties. Surprisingly, in a wild-type background, the dominant suppressor allele of ATP3 still allowed respiratory growth but increased the petite frequency. Similarly, a slow-growing respiratory deficient afo1- strain displayed an about twofold increase in spontaneous frequency of point mutations (comparable to the rho-zero strain) while the suppressed strain showed mutation frequency comparable to the respiratory-competent WT strain. We conclude, that phenotypes that result from afo1- are mostly explained by rapidly emerging mutations that compensate for the slow growth that typically follows respiratory deficiency.
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Affiliation(s)
- Jing Li
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
- Universite Cote d'Azur, CNRS, Inserm, IRCAN, Nice, France
| | | | - Johannes Hartl
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Department of Biochemistry, Charité University Medicine, Berlin Germany
| | - Manuela Weber
- Department of Biosciences, University of Salzburg, Austria
| | - Thomas Karl
- Department of Biosciences, University of Salzburg, Austria
| | | | - Michael Mülleder
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Department of Biochemistry, Charité University Medicine, Berlin Germany
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, 1Midland Rd, London NW1 1AT, UK
| | - Jakob Vowinckel
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Biognosys AG, Wagistrasse 21, 8952 Schlieren, Switzerland
| | - Hans Marx
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Michael Sauer
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Diethard Mattanovich
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Muthgasse 11, A-1190 Vienna, Austria
| | - Özge Ata
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Muthgasse 11, A-1190 Vienna, Austria
| | - Sonakshi De
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Muthgasse 11, A-1190 Vienna, Austria
| | | | | | - Bill Burhans
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, New York
| | - Chris Grant
- Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK
| | | | - Meryem Ralser
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, 1Midland Rd, London NW1 1AT, UK
| | | | | | | | | | - Campbell W Gourlay
- Department of Biosciences, University of Kent, Canterbury Kent CT2 7NJ, United Kingdom
| | - Jiri Hasek
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, Prague 4 142 20, Czech Republic
| | - Paul J Cullen
- Department of Biological Sciences, University at Buffalo, NY 14260
| | - Gianni Liti
- Institute for Research on Cancer and Ageing of Nice (IRCAN), CNRS, INSERM, Université Côte d'Azur, 06107 NICE, France
| | - Markus Ralser
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Department of Biochemistry, Charité University Medicine, Berlin Germany
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, 1Midland Rd, London NW1 1AT, UK
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6
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Su X, Rak M, Tetaud E, Godard F, Sardin E, Bouhier M, Gombeau K, Caetano-Anollés D, Salin B, Chen H, di Rago JP, Tribouillard-Tanvier D. Deregulating mitochondrial metabolite and ion transport has beneficial effects in yeast and human cellular models for NARP syndrome. Hum Mol Genet 2020; 28:3792-3804. [PMID: 31276579 DOI: 10.1093/hmg/ddz160] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/02/2019] [Accepted: 07/02/2019] [Indexed: 11/14/2022] Open
Abstract
The m.8993T>G mutation of the mitochondrial MT-ATP6 gene has been associated with numerous cases of neuropathy, ataxia and retinitis pigmentosa and maternally inherited Leigh syndrome, which are diseases known to result from abnormalities affecting mitochondrial energy transduction. We previously reported that an equivalent point mutation severely compromised proton transport through the ATP synthase membrane domain (FO) in Saccharomyces cerevisiae and reduced the content of cytochrome c oxidase (Complex IV or COX) by 80%. Herein, we report that overexpression of the mitochondrial oxodicarboxylate carrier (Odc1p) considerably increases Complex IV abundance and tricarboxylic acid-mediated substrate-level phosphorylation of ADP coupled to conversion of α-ketoglutarate into succinate in m.8993T>G yeast. Consistently in m.8993T>G yeast cells, the retrograde signaling pathway was found to be strongly induced in order to preserve α-ketoglutarate production; when Odc1p was overexpressed, this stress pathway returned to an almost basal activity. Similar beneficial effects were induced by a partial uncoupling of the mitochondrial membrane with the proton ionophore, cyanide m-chlorophenyl hydrazone. This chemical considerably improved the glutamine-based, respiration-dependent growth of human cytoplasmic hybrid cells that are homoplasmic for the m.8993T>G mutation. These findings shed light on the interdependence between ATP synthase and Complex IV biogenesis, which could lay the groundwork for the creation of nutritional or metabolic interventions for attenuating the effects of mtDNA mutations.
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Affiliation(s)
- Xin Su
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Malgorzata Rak
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Emmanuel Tetaud
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - François Godard
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Elodie Sardin
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Marine Bouhier
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Kewin Gombeau
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Derek Caetano-Anollés
- Genome Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Bénédicte Salin
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Huimei Chen
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu, China
| | - Jean-Paul di Rago
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France
| | - Déborah Tribouillard-Tanvier
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, CEDEX 33077 Bordeaux, France.,INSERM, Paris, France
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7
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Kucharczyk R, Dautant A, Gombeau K, Godard F, Tribouillard-Tanvier D, di Rago JP. The pathogenic MT-ATP6 m.8851T>C mutation prevents proton movements within the n-side hydrophilic cleft of the membrane domain of ATP synthase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:562-572. [PMID: 31181185 DOI: 10.1016/j.bbabio.2019.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 04/12/2019] [Accepted: 06/02/2019] [Indexed: 12/14/2022]
Abstract
Dozens of pathogenic mutations have been localized in the mitochondrial gene (MT-ATP6) that encodes the subunit a of ATP synthase. The subunit a together with a ring of identical subunits c moves protons across the mitochondrial inner membrane coupled to rotation of the subunit c-ring and ATP synthesis. One of these mutations, m.8851T>C, has been associated with bilateral striatal lesions of childhood (BSLC), a group of rare neurological disorders characterized by symmetric degeneration of the corpus striatum. It converts a highly conserved tryptophan residue into arginine at position 109 of subunit a (aW109R). We previously showed that an equivalent thereof in Saccharomyces cerevisiae (aW126R) severely impairs by an unknown mechanism the functioning of ATP synthase without any visible assembly/stability defect. Herein we show that ATP synthase function was recovered to varying degree by replacing the mutant arginine residue 126 with methionine, lysine or glycine or by replacing with methionine an arginine residue present at position 169 of subunit a (aR169). In recently described atomic structures of yeast ATP synthase, aR169 is at the center of a hydrophilic cleft along which protons are transported from the subunit c-ring to the mitochondrial matrix, in the proximity of the two residues known from a long time to be essential to the activity of FO (aR176 and cE59). We provide evidence that the aW126R change is responsible for electrostatic and steric hindrance that enables aR169 to engage in a salt bridge with cE59. As a result, aR176 cannot interact properly with cE5 and ATP synthase fails to effectively move protons across the mitochondrial membrane. In addition to insight into the pathogenic mechanism induced by the m.8851T>C mutation, the present study brings interesting information about the role of specific residues of subunit a in the energy-transducing activity of ATP synthase.
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Affiliation(s)
- Roza Kucharczyk
- Institut de Biochimie et Génétique Cellulaires of CNRS, Bordeaux University, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France; Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
| | - Alain Dautant
- Institut de Biochimie et Génétique Cellulaires of CNRS, Bordeaux University, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - Kewin Gombeau
- Institut de Biochimie et Génétique Cellulaires of CNRS, Bordeaux University, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - François Godard
- Institut de Biochimie et Génétique Cellulaires of CNRS, Bordeaux University, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - Déborah Tribouillard-Tanvier
- Institut de Biochimie et Génétique Cellulaires of CNRS, Bordeaux University, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
| | - Jean-Paul di Rago
- Institut de Biochimie et Génétique Cellulaires of CNRS, Bordeaux University, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France.
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8
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de Taffin de Tilques M, Tribouillard-Tanvier D, Tétaud E, Testet E, di Rago JP, Lasserre JP. Overexpression of mitochondrial oxodicarboxylate carrier (ODC1) preserves oxidative phosphorylation in a yeast model of Barth syndrome. Dis Model Mech 2017; 10:439-450. [PMID: 28188263 PMCID: PMC5399564 DOI: 10.1242/dmm.027540] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 02/04/2017] [Indexed: 12/21/2022] Open
Abstract
Cardiolipin (CL) is a diglycerol phospholipid mostly found in mitochondria where it optimizes numerous processes, including oxidative phosphorylation (OXPHOS). To function properly, CL needs to be unsaturated, which requires the acyltransferase tafazzin. Loss-of-function mutations in this protein are responsible for Barth syndrome (BTHS), presumably because of a diminished OXPHOS capacity. Here, we show that overexpressing Odc1p, a conserved oxodicarboxylic acid carrier located in the mitochondrial inner membrane, fully restores oxidative phosphorylation in a yeast model (taz1Δ) of BTHS. The rescuing activity involves the recovery of normal expression of key components that sustain oxidative phosphorylation, including cytochrome c and electron transport chain complexes IV and III, which are strongly downregulated in taz1Δ yeast. Interestingly, overexpression of Odc1p was also shown previously to rescue yeast models of mitochondrial diseases caused by defects in the assembly of ATP synthase and by mutations in the MPV17 protein that result in hepatocerebral mitochondrial DNA depletion syndrome. These findings define the transport of oxodicarboxylic acids across the inner membrane as a potential therapeutic target for a large spectrum of mitochondrial diseases, including BTHS.
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Affiliation(s)
- Maxence de Taffin de Tilques
- Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, CNRS UMR 5095, 1 rue Camille Saint-Saëns, Bordeaux cedex 33077, France
| | - Déborah Tribouillard-Tanvier
- Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, CNRS UMR 5095, 1 rue Camille Saint-Saëns, Bordeaux cedex 33077, France
| | - Emmanuel Tétaud
- Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, CNRS UMR 5095, 1 rue Camille Saint-Saëns, Bordeaux cedex 33077, France
| | - Eric Testet
- Université de Bordeaux, Laboratoire de biogenèse membranaire, CNRS UMR 5200, INRA Bordeaux Aquitaine BP81, 33883 Villenave d'Ornon Cédex, France
| | - Jean-Paul di Rago
- Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, CNRS UMR 5095, 1 rue Camille Saint-Saëns, Bordeaux cedex 33077, France
| | - Jean-Paul Lasserre
- Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, CNRS UMR 5095, 1 rue Camille Saint-Saëns, Bordeaux cedex 33077, France
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9
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Mejía-Barajas JA, Martínez-Mora JA, Salgado-Garciglia R, Noriega-Cisneros R, Ortiz-Avila O, Cortés-Rojo C, Saavedra-Molina A. Electron transport chain in a thermotolerant yeast. J Bioenerg Biomembr 2017; 49:195-203. [PMID: 28181110 DOI: 10.1007/s10863-017-9696-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/25/2017] [Indexed: 10/20/2022]
Abstract
Yeasts capable of growing and surviving at high temperatures are regarded as thermotolerant. For appropriate functioning of cellular processes and cell survival, the maintenance of an optimal redox state is critical of reducing and oxidizing species. We studied mitochondrial functions of the thermotolerant Kluyveromyces marxianus SLP1 and the mesophilic OFF1 yeasts, through the evaluation of its mitochondrial membrane potential (ΔΨm), ATPase activity, electron transport chain (ETC) activities, alternative oxidase activity, lipid peroxidation. Mitochondrial membrane potential and the cytoplasmic free Ca2+ ions (Ca2+ cyt) increased in the SLP1 yeast when exposed to high temperature, compared with the mesophilic yeast OFF1. ATPase activity in the mesophilic yeast diminished 80% when exposed to 40° while the thermotolerant SLP1 showed no change, despite an increase in the mitochondrial lipid peroxidation. The SLP1 thermotolerant yeast exposed to high temperature showed a diminution of 33% of the oxygen consumption in state 4. The uncoupled state 3 of oxygen consumption did not change in the mesophilic yeast when it had an increase of temperature, whereas in the thermotolerant SLP1 yeast resulted in an increase of 2.5 times when yeast were grown at 30o, while a decrease of 51% was observed when it was exposed to high temperature. The activities of the ETC complexes were diminished in the SLP1 when exposed to high temperature, but also it was distinguished an alternative oxidase activity. Our results suggest that the mitochondria state, particularly ETC state, is an important characteristic of the thermotolerance of the SLP1 yeast strain.
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Affiliation(s)
- Jorge A Mejía-Barajas
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico
| | - José A Martínez-Mora
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico
| | - Rafael Salgado-Garciglia
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico
| | - Ruth Noriega-Cisneros
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico
| | - Omar Ortiz-Avila
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico
| | - Christian Cortés-Rojo
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico
| | - Alfredo Saavedra-Molina
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030, Morelia, Michoacán, Mexico.
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Biallelic PPA2 Mutations Cause Sudden Unexpected Cardiac Arrest in Infancy. Am J Hum Genet 2016; 99:666-673. [PMID: 27523598 DOI: 10.1016/j.ajhg.2016.06.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 06/22/2016] [Indexed: 11/21/2022] Open
Abstract
Sudden unexpected death in infancy occurs in apparently healthy infants and remains largely unexplained despite thorough investigation. The vast majority of cases are sporadic. Here we report seven individuals from three families affected by sudden and unexpected cardiac arrest between 4 and 20 months of age. Whole-exome sequencing revealed compound heterozygous missense mutations in PPA2 in affected infants of each family. PPA2 encodes the mitochondrial pyrophosphatase, which hydrolyzes inorganic pyrophosphate into two phosphates. This is an essential activity for many biosynthetic reactions and for energy metabolism of the cell. We show that deletion of the orthologous gene in yeast (ppa2Δ) compromises cell viability due to the loss of mitochondria. Expression of wild-type human PPA2, but not PPA2 containing the mutations identified in affected individuals, preserves mitochondrial function in ppa2Δ yeast. Using a regulatable (doxycycline-repressible) gene expression system, we found that the pathogenic PPA2 mutations rapidly inactivate the mitochondrial energy transducing system and prevent the maintenance of a sufficient electrical potential across the inner membrane, which explains the subsequent disappearance of mitochondria from the mutant yeast cells. Altogether these data demonstrate that PPA2 is an essential gene in yeast and that biallelic mutations in PPA2 cause a mitochondrial disease leading to sudden cardiac arrest in infants.
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11
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Padma Priya P, Grover M, Tatu US, Natarajan V. Characterization of Precursor PfHsp60 in Plasmodium falciparum Cytosol during Its Asexual Development in Human Erythrocytes. PLoS One 2015; 10:e0136401. [PMID: 26317863 PMCID: PMC4552884 DOI: 10.1371/journal.pone.0136401] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 08/03/2015] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial heat shock protein 60 (Hsp60) is a nuclear encoded gene product that gets post-translationally translocated into the mitochondria. Using multiple approaches such as immunofluorescence experiments, isoelectric point analysis with two-dimensional gel electrophoresis, and mass spectrometric identification of the signal peptide, we show that Hsp60 from Plasmodium falciparum (PfHsp60) accumulates in the parasite cytoplasm during the ring, trophozoite, and schizont stages of parasite development before being imported into the parasite mitochondria. Using co-immunoprecipitation experiments with antibodies specific to cytoplasmic PfHsp90, PfHsp70-1, and PfHsp60, we show association of precursor PfHsp60 with cytoplasmic chaperone machinery. Metabolic labeling involving pulse and chase indicates translocation of the precursor pool into the parasite mitochondrion during chase. Analysis of results obtained with Geldanamycin treatment confirmed precursor PfHsp60 to be one of the clients for PfHsp90. Cytosolic chaperones bind precursor PfHsp60 prior to its import into the mitochondrion of the parasite. Our data suggests an inefficient co-ordination in the synthesis and translocation of mitochondrial PfHsp60 during asexual growth of malaria parasite in human erythrocytes.
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Affiliation(s)
- P. Padma Priya
- Department of Physics, Indian Institute of Science, Bangalore, Karnataka, India
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Manish Grover
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Utpal S. Tatu
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Vasant Natarajan
- Department of Physics, Indian Institute of Science, Bangalore, Karnataka, India
- * E-mail:
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12
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Fukuoh A, Cannino G, Gerards M, Buckley S, Kazancioglu S, Scialo F, Lihavainen E, Ribeiro A, Dufour E, Jacobs HT. Screen for mitochondrial DNA copy number maintenance genes reveals essential role for ATP synthase. Mol Syst Biol 2014; 10:734. [PMID: 24952591 PMCID: PMC4265055 DOI: 10.15252/msb.20145117] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The machinery of mitochondrial DNA (mtDNA) maintenance is only partially characterized and is of wide interest due to its involvement in disease. To identify novel components of this machinery, plus other cellular pathways required for mtDNA viability, we implemented a genome-wide RNAi screen in Drosophila S2 cells, assaying for loss of fluorescence of mtDNA nucleoids stained with the DNA-intercalating agent PicoGreen. In addition to previously characterized components of the mtDNA replication and transcription machineries, positives included many proteins of the cytosolic proteasome and ribosome (but not the mitoribosome), three proteins involved in vesicle transport, some other factors involved in mitochondrial biogenesis or nuclear gene expression, > 30 mainly uncharacterized proteins and most subunits of ATP synthase (but no other OXPHOS complex). ATP synthase knockdown precipitated a burst of mitochondrial ROS production, followed by copy number depletion involving increased mitochondrial turnover, not dependent on the canonical autophagy machinery. Our findings will inform future studies of the apparatus and regulation of mtDNA maintenance, and the role of mitochondrial bioenergetics and signaling in modulating mtDNA copy number.
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Affiliation(s)
- Atsushi Fukuoh
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate school of Medical Sciences, Fukuoka, Japan Department of Medical Laboratory Science, Junshin Gakuen University, Fukuoka, Japan
| | - Giuseppe Cannino
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Mike Gerards
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Suzanne Buckley
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Selena Kazancioglu
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Filippo Scialo
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Eero Lihavainen
- Department of Signal Processing, Tampere University of Technology, Tampere, Finland
| | - Andre Ribeiro
- Department of Signal Processing, Tampere University of Technology, Tampere, Finland
| | - Eric Dufour
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Howard T Jacobs
- BioMediTech and Tampere University Hospital, University of Tampere, Tampere, Finland Research Program of Molecular Neurology, University of Helsinki, Helsinki, Finland
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13
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Metabolic and environmental conditions determine nuclear genomic instability in budding yeast lacking mitochondrial DNA. G3-GENES GENOMES GENETICS 2014; 4:411-23. [PMID: 24374640 PMCID: PMC3962481 DOI: 10.1534/g3.113.010108] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mitochondrial dysfunctions are an internal cause of nuclear genome instability. Because mitochondria are key regulators of cellular metabolism, we have investigated a potential link between external growth conditions and nuclear chromosome instability in cells with mitochondrial defects. Using Saccharomyces cerevisiae, we found that cells lacking mitochondrial DNA (rho0 cells) have a unique feature, with nuclear chromosome instability that occurs in nondividing cells and strongly fluctuates depending on the cellular environment. Calorie restriction, lower growth temperatures, growth at alkaline pH, antioxidants (NAC, Tiron), or presence of nearby wild-type cells all efficiently stabilize nuclear genomes of rho0 cells, whereas high glucose and ethanol boost instability. In contrast, other respiratory mutants that still possess mitochondrial DNA (RHO(+)) keep fairly constant instability rates under the same growth conditions, like wild-type or other RHO(+) controls. Our data identify mitochondrial defects as an important driver of nuclear genome instability influenced by environmental factors.
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Moriguchi K, Yamamoto S, Tanaka K, Kurata N, Suzuki K. Trans-kingdom horizontal DNA transfer from bacteria to yeast is highly plastic due to natural polymorphisms in auxiliary nonessential recipient genes. PLoS One 2013; 8:e74590. [PMID: 24058593 PMCID: PMC3772842 DOI: 10.1371/journal.pone.0074590] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 08/05/2013] [Indexed: 11/30/2022] Open
Abstract
With the rapid accumulation of genomic information from various eukaryotes in the last decade, genes proposed to have been derived from recent horizontal gene transfer (HGT) events have been reported even in non-phagotrophic unicellular and multicellular organisms, but the molecular pathways underlying HGT remain to be explained. The development of in vitro HGT detection systems, which permit the molecular and genetic analyses of donor and recipient organisms and quantify HGT, are helpful in order to gain insight into mechanisms that may contribute to contemporary HGT events or may have contributed to past HGT events. We applied a horizontal DNA transfer system model based on conjugal gene transfer called trans-kingdom conjugation (TKC) from the prokaryote Escherichia coli to the eukaryote Saccharomyces cerevisiae, and assessed whether and to what extent genetic variations in the eukaryotic recipient affect its receptivity to TKC. Strains from a collection of 4,823 knock-out mutants of S. cerevisiae MAT-α haploids were tested for their individual TKC receptivity. Two types of mutants, an ssd1 mutant and respiratory mutants, which are also found in experimental strains and in nature widely, were identified as highly receptive mutants. The TKC efficiency for spontaneously accrued petite (rho−/0) mutants of the functional allele (SSD1-V) strain showed increased receptivity. The TKC efficiency of the ssd1Δ mutant was 36% for bacterial conjugation, while that of the petite/ssd1Δ double mutants was even higher (220% in average) compared to bacterial conjugation. This increased TKC receptivity was also observed when other conjugal transfer systems were applied and the donor bacterium was changed to Agrobacterium tumefaciens. These results support the idea that the genomes of certain eukaryotes have been exposed to exogenous DNA more frequently and continuously than previously thought.
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Affiliation(s)
- Kazuki Moriguchi
- Department of Biological Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
- * E-mail:
| | - Shinji Yamamoto
- Department of Biological Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Katsuyuki Tanaka
- Department of Biological Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Nori Kurata
- Plant Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Katsunori Suzuki
- Department of Biological Science, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
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15
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Hewitt VL, Gabriel K, Traven A. The ins and outs of the intermembrane space: diverse mechanisms and evolutionary rewiring of mitochondrial protein import routes. Biochim Biophys Acta Gen Subj 2013; 1840:1246-53. [PMID: 23994494 DOI: 10.1016/j.bbagen.2013.08.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Revised: 08/09/2013] [Accepted: 08/20/2013] [Indexed: 11/24/2022]
Abstract
BACKGROUND Mitochondrial biogenesis is an essential process in all eukaryotes. Import of proteins from the cytosol into mitochondria is a key step in organelle biogenesis. Recent evidence suggests that a given mitochondrial protein does not take the same import route in all organisms, suggesting that pathways of mitochondrial protein import can be rewired through evolution. Examples of this process so far involve proteins destined to the mitochondrial intermembrane space (IMS). SCOPE OF REVIEW Here we review the components, substrates and energy sources of the known mechanisms of protein import into the IMS. We discuss evolutionary rewiring of the IMS import routes, focusing on the example of the lactate utilisation enzyme cytochrome b2 (Cyb2) in the model yeast Saccharomyces cerevisiae and the human fungal pathogen Candida albicans. MAJOR CONCLUSIONS There are multiple import pathways used for protein entry into the IMS and they form a network capable of importing a diverse range of substrates. These pathways have been rewired, possibly in response to environmental pressures, such as those found in the niches in the human body inhabited by C. albicans. GENERAL SIGNIFICANCE We propose that evolutionary rewiring of mitochondrial import pathways can adjust the metabolic fitness of a given species to their environmental niche. This article is part of a Special Issue entitled Frontiers of Mitochondrial.
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Affiliation(s)
- Victoria L Hewitt
- Department of Biochemistry and Molecular Biology, Building 77, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne 3800, Australia.
| | - Kipros Gabriel
- Department of Biochemistry and Molecular Biology, Building 77, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne 3800, Australia.
| | - Ana Traven
- Department of Biochemistry and Molecular Biology, Building 77, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne 3800, Australia.
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16
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Wang D, Wang J, Bonamy GMC, Meeusen S, Brusch RG, Turk C, Yang P, Schultz PG. A small molecule promotes mitochondrial fusion in mammalian cells. Angew Chem Int Ed Engl 2012; 51:9302-5. [PMID: 22907892 DOI: 10.1002/anie.201204589] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Indexed: 12/15/2022]
Affiliation(s)
- Danling Wang
- Department of Chemistry, the Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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17
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Wang D, Wang J, Bonamy GMC, Meeusen S, Brusch RG, Turk C, Yang P, Schultz PG. A Small Molecule Promotes Mitochondrial Fusion in Mammalian Cells. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204589] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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18
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Fedoseeva IV, Pjatricas DV, Varakina NN, Rusaleva TM, Stepanov AV, Rikhvanov EG, Borovskii GB, Voinikov VK. Effect of amiodarone on thermotolerance and Hsp104p synthesis in the yeast Saccharomyces cerevisiae. BIOCHEMISTRY (MOSCOW) 2012; 77:78-86. [DOI: 10.1134/s0006297912010099] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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19
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Godard F, Tetaud E, Duvezin-Caubet S, di Rago JP. A genetic screen targeted on the FO component of mitochondrial ATP synthase in Saccharomyces cerevisiae. J Biol Chem 2011; 286:18181-9. [PMID: 21454598 DOI: 10.1074/jbc.m110.214825] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In yeast, the two main F(O) proton-translocating subunits of the ATP synthase (subunits 6/a and 9/c) are encoded by mitochondrial DNA (mtDNA). Unfortunately, mutations that inactivate the F(O) typically result in loss of mtDNA under the form of ρ(-)/ρ(0) cells. Thus, we have designed a novel genetic strategy to circumvent this problem. It exploits previous findings that a null mutation in the nuclear ATP16 gene encoding ATP synthase subunit δ results in massive and lethal F(O)-mediated protons leaks across the inner mitochondrial membrane. Mutations that inactivate the F(O) can thus, in these conditions, be selected positively as cell viability rescuing events. A first set of seven mutants was analyzed and all showed, as expected, very severe F(O) deficiencies. Two mutants carried nuclear mutations in known genes (AEP1, AEP2) required for subunit c expression. The five other mutations were located in mtDNA. Of these, three affect synthesis or stability of subunit a transcripts and the two last consisted in a single amino acid replacement in subunit c. One of the subunit c mutations is particularly interesting. It consists in an alanine to valine change at position 60 of subunit c adjacent to the essential glutamate of subunit c (at position 59) that interacts with the essential arginine 186 of subunit a. The properties of this mutant suggest that the contact zone between subunit a and the ten subunits c-ring structure only involves critical transient interactions confined to the region where protons are exchanged between the subunit a and the c-ring.
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Affiliation(s)
- François Godard
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 CNRS, Université Victor Segalen Bordeaux 2, 33077 Bordeaux, France
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20
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Loss of mitochondrial ATP synthase subunit beta (Atp2) alters mitochondrial and chloroplastic function and morphology in Chlamydomonas. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1533-9. [PMID: 20416275 DOI: 10.1016/j.bbabio.2010.04.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 04/12/2010] [Accepted: 04/14/2010] [Indexed: 01/22/2023]
Abstract
Mitochondrial F1FO ATP synthase (Complex V) catalyses ATP synthesis from ADP and inorganic phosphate using the proton-motive force generated by the substrate-driven electron transfer chain. In this work, we investigated the impact of the loss of activity of the mitochondrial enzyme in a photosynthetic organism. In this purpose, we inactivated by RNA interference the expression of the ATP2 gene, coding for the catalytic subunit beta, in the green alga Chlamydomonas reinhardtii. We demonstrate that in the absence of beta subunit, complex V is not assembled, respiratory rate is decreased by half and ATP synthesis coupled to the respiratory activity is fully impaired. Lack of ATP synthase also affects the morphology of mitochondria which are deprived of cristae. We also show that mutants are obligate phototrophs and that rearrangements of the photosynthetic apparatus occur in the chloroplast as a response to ATP synthase deficiency in mitochondria. Altogether, our results contribute to the understanding of the yet poorly studied bioenergetic interactions between organelles in photosynthetic organisms.
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Laco J, Zeman I, Pevala V, Polcic P, Kolarov J. Adenine nucleotide transport via Sal1 carrier compensates for the essential function of the mitochondrial ADP/ATP carrier. FEMS Yeast Res 2010; 10:290-6. [PMID: 20141534 DOI: 10.1111/j.1567-1364.2010.00606.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The mitochondrial ADP/ATP carrier (Aac2p) of Saccharomyces cerevisiae links two biochemical pathways, glycolysis in the cytosol and oxidative phosphorylation in the mitochondria, by exchanging their common substrates and products across the inner mitochondrial membrane. Recently, the product of the SAL1 gene, which is essential in cells lacking Aac2p, has been implicated in a similar communication. However, the mechanism by which Sal1p rescues the growth of Deltaaac2 mutants is not clear and it was proposed that both Sal1p and Aac2p share a common vital function other than ADP/ATP exchange. Here, the impact of SAL1 deletion on mitochondrial reactions involving either synthesis or hydrolysis of ATP was investigated. We show that adenine nucleotide transport activity related to Sal1p can be demonstrated in isolated mitochondria as well as in intact cells under conditions when Aac2-mediated exchange is not functional. Our results indicate that the vital role of both Sal1p and Aac2p is to maintain the essential intramitochondrial ATP pool owing to their ability to transport adenine nucleotides.
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Affiliation(s)
- Juraj Laco
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
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Consequences of the pathogenic T9176C mutation of human mitochondrial DNA on yeast mitochondrial ATP synthase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1105-12. [PMID: 20056103 DOI: 10.1016/j.bbabio.2009.12.022] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2009] [Revised: 12/23/2009] [Accepted: 12/27/2009] [Indexed: 12/14/2022]
Abstract
Several human neurological disorders have been associated with various mutations affecting mitochondrial enzymes involved in cellular ATP production. One of these mutations, T9176C in the mitochondrial DNA (mtDNA), changes a highly conserved leucine residue into proline at position 217 of the mitochondrially encoded Atp6p (or a) subunit of the F1FO-ATP synthase. The consequences of this mutation on the mitochondrial ATP synthase are still poorly defined. To gain insight into the primary pathogenic mechanisms induced by T9176C, we have investigated the consequences of this mutation on the ATP synthase of yeast where Atp6p is also encoded by the mtDNA. In vitro, yeast atp6-T9176C mitochondria showed a 30% decrease in the rate of ATP synthesis. When forcing the F1FO complex to work in the reverse mode, i.e. F1-catalyzed hydrolysis of ATP coupled to proton transport out of the mitochondrial matrix, the mutant showed a normal proton-pumping activity and this activity was fully sensitive to oligomycin, an inhibitor of the ATP synthase proton channel. However, under conditions of maximal ATP hydrolytic activity, using non-osmotically protected mitochondria, the mutant ATPase activity was less efficiently inhibited by oligomycin (60% inhibition versus 85% for the wild type control). Blue Native Polyacrylamide Gel Electrophoresis analyses revealed that atp6-T9176C yeast accumulated rather good levels of fully assembled ATP synthase complexes. However, a number of sub-complexes (F1, Atp9p-ring, unassembled alpha-F1 subunits) could be detected as well, presumably because of a decreased stability of Atp6p within the ATP synthase. Although the oxidative phosphorylation capacity was reduced in atp6-T9176C yeast, the number of ATP molecules synthesized per electron transferred to oxygen was similar compared with wild type yeast. It can therefore be inferred that the coupling efficiency within the ATP synthase was mostly unaffected and that the T9176C mutation did not increase the proton permeability of the mitochondrial inner membrane.
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Kucharczyk R, Salin B, di Rago JP. Introducing the human Leigh syndrome mutation T9176G into Saccharomyces cerevisiae mitochondrial DNA leads to severe defects in the incorporation of Atp6p into the ATP synthase and in the mitochondrial morphology. Hum Mol Genet 2009; 18:2889-98. [DOI: 10.1093/hmg/ddp226] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Traba J, Satrústegui J, del Arco A. Transport of adenine nucleotides in the mitochondria of Saccharomyces cerevisiae: interactions between the ADP/ATP carriers and the ATP-Mg/Pi carrier. Mitochondrion 2009; 9:79-85. [PMID: 19460304 DOI: 10.1016/j.mito.2009.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 10/09/2008] [Accepted: 01/05/2009] [Indexed: 01/09/2023]
Abstract
The ADP/ATP and ATP-Mg/Pi carriers are widespread among eukaryotes and constitute two systems to transport adenine nucleotides in mitochondria. ADP/ATP carriers carry out an electrogenic exchange of ADP for ATP essential for oxidative phosphorylation, whereas ATP-Mg/Pi carriers perform an electroneutral exchange of ATP-Mg for phosphate and are able to modulate the net content of adenine nucleotides in mitochondria. The functional interplay between both carriers has been shown to modulate viability in Saccharomyces cerevisiae. The simultaneous absence of both carriers is lethal. In the light of the new evidence we suggest that, in addition to exchange of cytosolic ADP for mitochondrial ATP, the specific function of the ADP/ATP carriers required for respiration, both transporters have a second function, which is the import of cytosolic ATP in mitochondria. The participation of these carriers in the generation of mitochondrial membrane potential is discussed. Both are necessary for the function of the mitochondrial protein import and assembly systems, which are the only essential mitochondrial functions in S. cerevisiae.
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Affiliation(s)
- Javier Traba
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, UAM-CSIC, Universidad Autónoma, CIBER de Enfermedades Raras, c/Nicolas Cabrera 1, 28049 Madrid, Spain.
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Traba J, Froschauer EM, Wiesenberger G, Satrústegui J, Del Arco A. Yeast mitochondria import ATP through the calcium-dependent ATP-Mg/Pi carrier Sal1p, and are ATP consumers during aerobic growth in glucose. Mol Microbiol 2008; 69:570-85. [PMID: 18485069 DOI: 10.1111/j.1365-2958.2008.06300.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sal1p, a novel Ca2+-dependent ATP-Mg/Pi carrier, is essential in yeast lacking all adenine nucleotide translocases. By targeting luciferase to the mitochondrial matrix to monitor mitochondrial ATP levels, we show in isolated mitochondria that both ATP-Mg and free ADP are taken up by Sal1p with a K(m) of 0.20 +/- 0.03 mM and 0.28 +/- 0.06 mM respectively. Nucleotide transport along Sal1p is strictly Ca2+ dependent. Ca2+ increases the V(max) with a S(0.5) of 15 muM, and no changes in the K(m) for ATP-Mg. Glucose sensing in yeast generates Ca2+ transients involving Ca2+ influx from the external medium. We find that carbon-deprived cells respond to glucose with an immediate increase in mitochondrial ATP levels which is not observed in the presence of EGTA or in Sal1p-deficient cells. Moreover, we now report that during normal aerobic growth on glucose, yeast mitochondria import ATP from the cytosol and hydrolyse it through H+-ATP synthase. We identify two pathways for ATP uptake in mitochondria, the ADP/ATP carriers and Sal1p. Thus, during exponential growth on glucose, mitochondria are ATP consumers, as those from cells growing in anaerobic conditions or deprived of mitochondrial DNA which depend on cytosolic ATP and mitochondrial ATPase working in reverse to generate a mitochondrial membrane potential. In conclusion, the results show that growth on glucose requires ATP hydrolysis in mitochondria and recruits Sal1p as a Ca2+-dependent mechanism to import ATP-Mg from the cytosol. Whether this mechanism is used under similar settings in higher eukaryotes is an open question.
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Affiliation(s)
- Javier Traba
- Departamento de Biologia Molecular, Centro de Biología Molecular Severo Ochoa UAM-CSIC, CIBER de Enfermedades Raras (CIBERER), Universidad Autónoma, Madrid, Spain
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van Raam BJ, Sluiter W, de Wit E, Roos D, Verhoeven AJ, Kuijpers TW. Mitochondrial membrane potential in human neutrophils is maintained by complex III activity in the absence of supercomplex organisation. PLoS One 2008; 3:e2013. [PMID: 18431494 PMCID: PMC2295260 DOI: 10.1371/journal.pone.0002013] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Accepted: 03/11/2008] [Indexed: 12/13/2022] Open
Abstract
Background Neutrophils depend mainly on glycolysis for their energy provision. Their mitochondria maintain a membrane potential (Δψm), which is usually generated by the respiratory chain complexes. We investigated the source of Δψm in neutrophils, as compared to peripheral blood mononuclear leukocytes and HL-60 cells, and whether neutrophils can still utilise this Δψm for the generation of ATP. Methods and Principal Findings Individual activity of the oxidative phosphorylation complexes was significantly reduced in neutrophils, except for complex II and V, but Δψm was still decreased by inhibition of complex III, confirming the role of the respiratory chain in maintaining Δψm. Complex V did not maintain Δψm by consumption of ATP, as has previously been suggested for eosinophils. We show that complex III in neutrophil mitochondria can receive electrons from glycolysis via the glycerol-3-phosphate shuttle. Furthermore, respiratory supercomplexes, which contribute to efficient coupling of the respiratory chain to ATP synthesis, were lacking in neutrophil mitochondria. When HL-60 cells were differentiated to neutrophil-like cells, they lost mitochondrial supercomplex organisation while gaining increased aerobic glycolysis, just like neutrophils. Conclusions We show that neutrophils can maintain Δψm via the glycerol-3-phosphate shuttle, whereby their mitochondria play an important role in the regulation of aerobic glycolysis, rather than producing energy themselves. This peculiar mitochondrial phenotype is acquired during differentiation from myeloid precursors.
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Affiliation(s)
- Bram J. van Raam
- Department of Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
- Emma Children's Hospital, Academic Medical Centre, Department of Paediatric Immunology, University of Amsterdam, Amsterdam, The Netherlands
| | - Wim Sluiter
- Department of Biochemistry, Mitochondrial Research Unit, Erasmus MC, Rotterdam, The Netherlands
| | - Elly de Wit
- Department of Biochemistry, Mitochondrial Research Unit, Erasmus MC, Rotterdam, The Netherlands
| | - Dirk Roos
- Department of Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
| | - Arthur J. Verhoeven
- Department of Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
- * E-mail:
| | - Taco W. Kuijpers
- Department of Blood Cell Research, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
- Emma Children's Hospital, Academic Medical Centre, Department of Paediatric Immunology, University of Amsterdam, Amsterdam, The Netherlands
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Role of gamma-subunit N- and C-termini in assembly of the mitochondrial ATP synthase in yeast. J Mol Biol 2008; 377:1314-23. [PMID: 18328502 DOI: 10.1016/j.jmb.2008.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 01/25/2008] [Accepted: 02/01/2008] [Indexed: 11/23/2022]
Abstract
The gamma-subunit is required for the assembly of ATP synthases and plays a crucial role in their catalytic activity. We stepwise shortened the N-terminus and the C-terminus of the gamma-subunit in the mitochondrial ATP synthase of yeast and investigated the relevance of these segments in the assembly of the enzyme and in the growth of the cells. We found that a deletion of 9 residues at the N-terminus or 20 residues at the C-terminus still allowed efficient import of the subunit into mitochondria; however, the assembly of both monomeric and dimeric holoenzymes was partially impaired. gamma-Subunits lacking 13 N-terminal residues or 30 C-terminal residues were not assembled. Yeast strains expressing either of the truncated gamma-subunits did not grow on non-fermentable carbon sources, indicating that non-assembled parts of the ATP synthase accumulated and impaired essential mitochondrial functions.
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28
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Regulatory mechanisms of proton-translocating F(O)F (1)-ATP synthase. Results Probl Cell Differ 2007; 45:279-308. [PMID: 18026702 DOI: 10.1007/400_2007_043] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
H(+)-F(O)F(1)-ATP synthase catalyzes synthesis of ATP from ADP and inorganic phosphate using the energy of transmembrane electrochemical potential difference of proton (deltamu(H)(+). The enzyme can also generate this potential difference by working as an ATP-driven proton pump. Several regulatory mechanisms are known to suppress the ATPase activity of F(O)F(1): 1. Non-competitive inhibition by MgADP, a feature shared by F(O)F(1) from bacteria, chloroplasts and mitochondria 2. Inhibition by subunit epsilon in chloroplast and bacterial enzyme 3. Inhibition upon oxidation of two cysteines in subunit gamma in chloroplast F(O)F(1) 4. Inhibition by an additional regulatory protein (IF(1)) in mitochondrial enzyme In this review we summarize the information available on these regulatory mechanisms and discuss possible interplay between them.
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29
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Andersen AZ, Poulsen AK, Brasen JC, Olsen LF. On-line measurements of oscillating mitochondrial membrane potential in glucose-fermenting Saccharomyces cerevisiae. Yeast 2007; 24:731-9. [PMID: 17568453 DOI: 10.1002/yea.1508] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We employed the fluorescent cyanine dye DiOC(2)(3) to measure membrane potential in semi-anaerobic yeast cells under conditions where glycolysis was oscillating. Oscillations in glycolysis were studied by means of the naturally abundant nicotinamide adenine dinucleotide (NADH). We found that the mitochondrial membrane potential was oscillating, and that these oscillations displayed the same frequency and duration as the NADH oscillations. It was confirmed that DiOC(2)(3) localizes itself in the mitochondrial membrane and thus reports qualitative changes solely in mitochondrial membrane potential. Our studies showed that glycolytic oscillations perturb the mitochondrial membrane potential and that the mitochondria do not have any controlling effect on the dynamics of glycolysis under these conditions. Depolarization of the mitochondrial membrane by addition of FCCP quenched mitochondrial membrane potential oscillations and delocalized DiOC(2)(3), while glycolysis continued to oscillate unaffected.
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Affiliation(s)
- Ann Zahle Andersen
- University of Southern Denmark, Department of Biochemistry and Molecular Biology, CelCom, Campusvej 55, 5230 Odense M, Denmark.
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30
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Seo JG, Lai CY, Miceli MV, Jazwinski SM. A novel role of peroxin PEX6: suppression of aging defects in mitochondria. Aging Cell 2007; 6:405-13. [PMID: 17465979 DOI: 10.1111/j.1474-9726.2007.00291.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Yeast cells become older with each division, but their daughters are born young. Mutational analysis shows that maintenance of this age asymmetry requires segregation of a complement of active mitochondria to daughters and that this process breaks down in older mother cells. This decline has implications for stem cell aging in higher organisms. PEX6, a peroxisome biogenesis gene, has been isolated as a multicopy suppressor of an atp2 age asymmetry mutant. Suppression depended on the presence of particular amino acid residues in Atp2p, and required adenosine triphosphate (ATP) binding and/or ATP hydrolysis activity of Pex6p. Extra copies of PEX6 corrected the deficit in Atp2p in mitochondria in the mutant by improving its import kinetics, resulting in near normal mitochondrial inheritance by daughter cells. The novel function of Pex6p described here may provide insights into peroxisomal and mitochondrial disorders and into metabolic diseases in general.
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Affiliation(s)
- Jae-Gu Seo
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
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31
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Satrústegui J, Pardo B, Del Arco A. Mitochondrial Transporters as Novel Targets for Intracellular Calcium Signaling. Physiol Rev 2007; 87:29-67. [PMID: 17237342 DOI: 10.1152/physrev.00005.2006] [Citation(s) in RCA: 203] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ca2+signaling in mitochondria is important to tune mitochondrial function to a variety of extracellular stimuli. The main mechanism is Ca2+entry in mitochondria via the Ca2+uniporter followed by Ca2+activation of three dehydrogenases in the mitochondrial matrix. This results in increases in mitochondrial NADH/NAD ratios and ATP levels and increased substrate uptake by mitochondria. We review evidence gathered more than 20 years ago and recent work indicating that substrate uptake, mitochondrial NADH/NAD ratios, and ATP levels may be also activated in response to cytosolic Ca2+signals via a mechanism that does not require the entry of Ca2+in mitochondria, a mechanism depending on the activity of Ca2+-dependent mitochondrial carriers (CaMC). CaMCs fall into two groups, the aspartate-glutamate carriers (AGC) and the ATP-Mg/Picarriers, also named SCaMC (for short CaMC). The two mammalian AGCs, aralar and citrin, are members of the malate-aspartate NADH shuttle, and citrin, the liver AGC, is also a member of the urea cycle. Both types of CaMCs are activated by Ca2+in the intermembrane space and function together with the Ca2+uniporter in decoding the Ca2+signal into a mitochondrial response.
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Affiliation(s)
- Jorgina Satrústegui
- Departamento de Biología Molecular Centro de Biología Molecular "Severo Ochoa" UAM-CSIC, Facultad de Ciencias, Universidad Autónoma, Madrid, Spain.
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32
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Martínez-Diez M, Santamaría G, Ortega ÁD, Cuezva JM. Biogenesis and dynamics of mitochondria during the cell cycle: significance of 3'UTRs. PLoS One 2006; 1:e107. [PMID: 17205111 PMCID: PMC1762426 DOI: 10.1371/journal.pone.0000107] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Accepted: 11/24/2006] [Indexed: 11/18/2022] Open
Abstract
Nowadays, we are facing a renaissance of mitochondria in cancer biology. However, our knowledge of the basic cell biology and on the timing and mechanisms that control the biosynthesis of mitochondrial constituents during progression through the cell cycle of mammalian cells remain largely unknown. Herein, we document the in vivo changes on mitochondrial morphology and dynamics that accompany cellular mitosis, and illustrate the following key points of the biogenesis of mitochondria during progression of liver cells through the cycle: (i) the replication of nuclear and mitochondrial genomes is synchronized during cellular proliferation, (ii) the accretion of OXPHOS proteins is asynchronously regulated during proliferation being the synthesis of beta-F1-ATPase and Hsp60 carried out also at G2/M and, (iii) the biosynthesis of cardiolipin is achieved during the S phase, although full development of the mitochondrial membrane potential (DeltaPsim) is attained at G2/M. Furthermore, we demonstrate using reporter constructs that the mechanism regulating the accretion of beta-F1-ATPase during cellular proliferation is controlled at the level of mRNA translation by the 3'UTR of the transcript. The 3'UTR-driven synthesis of the protein at G2/M is essential for conferring to the daughter cells the original phenotype of the parental cell. Our findings suggest that alterations on this process may promote deregulated beta-F1-ATPase expression in human cancer.
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33
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Duvezin-Caubet S, Rak M, Lefebvre-Legendre L, Tetaud E, Bonnefoy N, di Rago JP. A “Petite Obligate” Mutant of Saccharomyces cerevisiae. J Biol Chem 2006; 281:16305-13. [PMID: 16608846 DOI: 10.1074/jbc.m513805200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Within the mitochondrial F(1)F(0)-ATP synthase, the nucleus-encoded delta-F(1) subunit plays a critical role in coupling the enzyme proton translocating and ATP synthesis activities. In Saccharomyces cerevisiae, deletion of the delta subunit gene (Deltadelta) was shown to result in a massive destabilization of the mitochondrial genome (mitochondrial DNA; mtDNA) in the form of 100% rho(-)/rho degrees petites (i.e. cells missing a large portion (>50%) of the mtDNA (rho(-)) or totally devoid of mtDNA (rho degrees )). Previous work has suggested that the absence of complete mtDNA (rho(+)) in Deltadelta yeast is a consequence of an uncoupling of the ATP synthase in the form of a passive proton transport through the enzyme (i.e. not coupled to ATP synthesis). However, it was unclear why or how this ATP synthase defect destabilized the mtDNA. We investigated this question using a nonrespiratory gene (ARG8(m)) inserted into the mtDNA. We first show that retention of functional mtDNA is lethal to Deltadelta yeast. We further show that combined with a nuclear mutation (Deltaatp4) preventing the ATP synthase proton channel assembly, a lack of delta subunit fails to destabilize the mtDNA, and rho(+) Deltadelta cells become viable. We conclude that Deltadelta yeast cannot survive when it has the ability to synthesize the ATP synthase proton channel. Accordingly, the rho(-)/rho degrees mutation can be viewed as a rescuing event, because this mutation prevents the synthesis of the two mtDNA-encoded subunits (Atp6p and Atp9p) forming the core of this channel. This is the first report of what we have called a "petite obligate" mutant of S. cerevisiae.
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Affiliation(s)
- Stéphane Duvezin-Caubet
- Institut de Biochimie et Génétique Cellulaires, Université Victor Segalen, 1 Rue Camille Saint-Saëns, Bordeaux 33077 cedex, France
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34
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Feniouk BA, Suzuki T, Yoshida M. The role of subunit epsilon in the catalysis and regulation of FOF1-ATP synthase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1757:326-38. [PMID: 16701076 DOI: 10.1016/j.bbabio.2006.03.022] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Revised: 03/13/2006] [Accepted: 03/30/2006] [Indexed: 10/24/2022]
Abstract
The regulation of ATP synthase activity is complex and involves several distinct mechanisms. In bacteria and chloroplasts, subunit epsilon plays an important role in this regulation, (i) affecting the efficiency of coupling, (ii) influencing the catalytic pathway, and (iii) selectively inhibiting ATP hydrolysis activity. Several experimental studies indicate that the regulation is achieved through large conformational transitions of the alpha-helical C-terminal domain of subunit epsilon that occur in response to membrane energization, change in ATP/ADP ratio or addition of inhibitors. This review summarizes the experimental data obtained on different organisms that clarify some basic features as well as some molecular details of this regulatory mechanism. Multiple functions of subunit epsilon, its role in the difference between the catalytic pathways of ATP synthesis and hydrolysis and its influence on the inhibition of ATP hydrolysis by ADP are also discussed.
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Affiliation(s)
- Boris A Feniouk
- ATP System Project, Exploratory Research for Advanced Technology, Japan Science and Technology Corporation (JST), 5800-3 Nagatsuta, Midori-ku, Yokohama 226-0026, Japan.
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35
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Schnaufer A, Clark-Walker GD, Steinberg AG, Stuart K. The F1-ATP synthase complex in bloodstream stage trypanosomes has an unusual and essential function. EMBO J 2005; 24:4029-40. [PMID: 16270030 PMCID: PMC1356303 DOI: 10.1038/sj.emboj.7600862] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Accepted: 10/10/2005] [Indexed: 11/09/2022] Open
Abstract
Survival of bloodstream form Trypanosoma brucei, the agent of African sleeping sickness, normally requires mitochondrial gene expression, despite the absence of oxidative phosphorylation in this stage of the parasite's life cycle. Here we report that silencing expression of the alpha subunit of the mitochondrial F(1)-ATP synthase complex is lethal for bloodstream stage T. brucei as well as for T. evansi, a closely related species that lacks mitochondrial protein coding genes (i.e. is dyskinetoplastic). Our results suggest that the lethal effect is due to collapse of the mitochondrial membrane potential, which is required for mitochondrial function and biogenesis. We also identified a mutation in the gamma subunit of F(1) that is likely to be involved in circumventing the requirement for mitochondrial gene expression in another dyskinetoplastic form. Our data reveal that the mitochondrial ATP synthase complex functions in the bloodstream stage opposite to that in the insect stage and in most other eukaryotes, namely using ATP hydrolysis to generate the mitochondrial membrane potential.
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Affiliation(s)
- Achim Schnaufer
- Seattle Biomedical Research Institute, Seattle, WA, USA
- Seattle Biomedical Research Institute, 307 Westlake Ave N, Suite 500, Seattle, WA 98109-5219, USA. Tel.: +1 206 256 7488; Fax: +1 206 256 7229; E-mail:
| | - G Desmond Clark-Walker
- Molecular Genetics and Evolution, Research School of Biological Sciences, The Australian National University, Canberra, ACT, Australia
| | | | - Ken Stuart
- Seattle Biomedical Research Institute, Seattle, WA, USA
- Department of Pathobiology, University of Washington, Seattle, WA, USA
- Seattle Biomedical Research Institute, 307 Westlake Ave N, Suite 500, Seattle, WA 98109-5219, USA. Tel.: +1 206 256 7316; Fax: +1 206 256 7229; E-mail:
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Reiner S, Micolod D, Zellnig G, Schneiter R. A genomewide screen reveals a role of mitochondria in anaerobic uptake of sterols in yeast. Mol Biol Cell 2005; 17:90-103. [PMID: 16251356 PMCID: PMC1345649 DOI: 10.1091/mbc.e05-06-0515] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The mechanisms that govern intracellular transport of sterols in eukaryotic cells are not well understood. Saccharomyces cerevisiae is a facultative anaerobic organism that becomes auxotroph for sterols and unsaturated fatty acids in the absence of oxygen. To identify pathways that are required for uptake and transport of sterols, we performed a systematic screen of the yeast deletion mutant collection for genes that are required for growth under anaerobic conditions. Of the approximately 4800 nonessential genes represented in the deletion collection, 37 were essential for growth under anaerobic conditions. These affect a wide range of cellular functions, including biosynthetic pathways for certain amino acids and cofactors, reprogramming of transcription and translation, mitochondrial function and biogenesis, and membrane trafficking. Thirty-three of these mutants failed to grow on lipid-supplemented media when combined with a mutation in HEM1, which mimics anaerobic conditions in the presence of oxygen. Uptake assays with radio- and fluorescently labeled cholesterol revealed that 17 of the 33 mutants strongly affect uptake and/or esterification of exogenously supplied cholesterol. Examination of the subcellular distribution of sterols in these uptake mutants by cell fractionation and fluorescence microscopy indicates that some of the mutants block incorporation of cholesterol into the plasma membrane, a presumably early step in sterol uptake. Unexpectedly, the largest class of uptake mutants is affected in mitochondrial functions, and many of the uptake mutants show electron-dense mitochondrial inclusions. These results indicate that a hitherto uncharacterized mitochondrial function is required for sterol uptake and/or transport under anaerobic conditions and are discussed in light of the fact that mitochondrial import of cholesterol is required for steroidogenesis in vertebrate cells.
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Affiliation(s)
- Sonja Reiner
- Institute of Biochemistry, Graz University of Technology, 8010 Graz, Austria
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37
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Stribinskis V, Heyman HC, Ellis SR, Steffen MC, Martin NC. Rpm2p, a component of yeast mitochondrial RNase P, acts as a transcriptional activator in the nucleus. Mol Cell Biol 2005; 25:6546-58. [PMID: 16024791 PMCID: PMC1190346 DOI: 10.1128/mcb.25.15.6546-6558.2005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rpm2p, a protein subunit of yeast mitochondrial RNase P, has another function that is essential in cells lacking the wild-type mitochondrial genome. This function does not require the mitochondrial leader sequence and appears to affect transcription of nuclear genes. Rpm2p expressed as a fusion protein with green fluorescent protein localizes to the nucleus and activates transcription from promoters containing lexA-binding sites when fused to a heterologous DNA binding domain, lexA. The transcriptional activation region of Rpm2p contains two leucine zippers that are required for transcriptional activation and are conserved in the distantly related yeast Candida glabrata. The presence of a mitochondrial leader sequence does not prevent a portion of Rpm2p from locating to the nucleus, and several observations suggest that the nuclear location and transcriptional activation ability of Rpm2p are physiologically significant. The ability of RPM2 alleles to suppress tom40-3, a temperature-sensitive mutant of a component of the mitochondrial import apparatus, correlates with their ability to transactivate the reporter genes with lexA-binding sites. In cells lacking mitochondrial DNA, Rpm2p influences the levels of TOM40, TOM6, TOM20, TOM22, and TOM37 mRNAs, which encode components of the mitochondrial import apparatus, but not that of TOM70 mRNA. It also affects HSP60 and HSP10 mRNAs that encode essential mitochondrial chaperones. Rpm2p also increases the level of Tom40p, as well as Hsp60p, but not Atp2p, suggesting that some, but not all, nucleus-encoded mitochondrial components are affected.
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Affiliation(s)
- Vilius Stribinskis
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Louisville, Louisville, KY 40292, USA
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38
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Rikhvanov EG, Varakina NN, Rusaleva TM, Rachenko EI, Knorre DA, Voinikov VK. Do mitochondria regulate the heat-shock response in Saccharomyces cerevisiae? Curr Genet 2005; 48:44-59. [PMID: 15983831 DOI: 10.1007/s00294-005-0587-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 04/21/2005] [Accepted: 05/04/2005] [Indexed: 11/27/2022]
Abstract
A mild heat shock induces the synthesis of heat-shock proteins (hsps), which protect cells from damage during more extreme heat exposure. The nature of the signals that induce transcription of heat shock-regulated genes remains conjectural. In this work we studied the role of mitochondria in regulating hsps synthesis in Saccharomyces cerevisiae. The results obtained clearly indicate that a mild heat shock elicits a hyperpolarization of the inner mitochondrial membrane and such an event is one of several signals triggering the chain of reactions that activates the expression of the HSP104 gene and probably the expression of other heat shock-regulated genes in S. cerevisiae. The uncouplers or mitochondrial inhibitors which are capable of dissipating the potential on the inner mitochondrial membrane under particular experimental conditions prevent the synthesis of Hsp104 induced by mild heat shock and thus inhibit the development of induced thermotolerance. It is suggested that cAMP-dependent protein kinase A is participating in the mitochondrial regulation of nuclear genes.
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Affiliation(s)
- Eugene G Rikhvanov
- Siberian Institute of Plant Physiology and Biochemistry, Siberian Division, Russian Academy of Sciences, Lermontov St. 132, Irkutsk 664033, Russia.
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39
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Schwimmer C, Lefebvre-Legendre L, Rak M, Devin A, Slonimski PP, di Rago JP, Rigoulet M. Increasing mitochondrial substrate-level phosphorylation can rescue respiratory growth of an ATP synthase-deficient yeast. J Biol Chem 2005; 280:30751-9. [PMID: 15975925 DOI: 10.1074/jbc.m501831200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In a previous study we have identified Fmc1p, a mitochondrial protein involved in the assembly/stability of the yeast F0F1-ATP synthase at elevated temperatures. The deltafmc1 mutant was shown to exhibit a severe phenotype of very slow growth on respiratory substrates at 37 degrees C. We have isolated ODC1 as a multicopy suppressor of the fmc1 deletion restoring a good respiratory growth. Odc1p expression level was estimated to be at least 10 times higher in mitochondria isolated from the deltafmc1/ODC1 transformant as compared with wild type mitochondria. Interestingly, ODC1 encodes an oxodicarboxylate carrier, which transports alpha-ketoglutarate and alpha-ketoadipate or any other transported tricarboxylic acid cycle intermediate in a counter-exchange through the inner mitochondrial membrane. We show that the suppression of the respiratory-growth-deficient fmc1 by the overexpressed Odc1p was not due to a restored stable ATP synthase. Instead, the rescuing mechanism involves an increase in the flux of tricarboxylic acid cycle intermediate from the cytosol into the mitochondria, leading to an increase in the alpha-ketoglutarate oxidative decarboxylation, resulting in an increase in mitochondrial substrate-level-dependent ATP synthesis. This mechanism of metabolic bypass of a defective ATP synthase unravels the physiological importance of intramitochondrial substrate-level phosphorylations. This unexpected result might be of interest for the development of therapeutic solutions in pathologies associated with defects in the oxidative phosphorylation system.
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Affiliation(s)
- Christine Schwimmer
- Institut de Biochimie et Génétique Cellulaires CNRS/Université Victor Ségalen Bordeaux2, 1 rue Camille St Saëns, 33077 Bordeaux Cedex, France.
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Priault M, Salin B, Schaeffer J, Vallette FM, di Rago JP, Martinou JC. Impairing the bioenergetic status and the biogenesis of mitochondria triggers mitophagy in yeast. Cell Death Differ 2005; 12:1613-21. [PMID: 15947785 DOI: 10.1038/sj.cdd.4401697] [Citation(s) in RCA: 225] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Autophagy, a highly regulated programme found in almost all eukaryotes, is mainly viewed as a catabolic process that degrades nonessential cellular components into molecular building blocks, subsequently available for biosynthesis at a lesser expense than de novo synthesis. Autophagy is largely known to be regulated by nutritional conditions. Here we show that, in yeast cells grown under nonstarving conditions, autophagy can be induced by mitochondrial dysfunction. Electron micrographs and biochemical studies show that an autophagic activity can result from impairing the mitochondrial electrochemical transmembrane potential. Furthermore, mitochondrial damage-induced autophagy results in the preferential degradation of impaired mitochondria (mitophagy), before leading to cell death. Mitophagy appears to rely on classical macroautophagy machinery while being independent of cellular ATP collapse. These results suggest that in this case, autophagy can be envisioned either as a process of mitochondrial quality control, or as an ultimate cellular response triggered when cells are overwhelmed with damaged mitochondria.
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Affiliation(s)
- M Priault
- Département de Biologie Cellulaire, Université de Genève, Suisse.
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Ackerman SH, Tzagoloff A. Function, structure, and biogenesis of mitochondrial ATP synthase. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2005; 80:95-133. [PMID: 16164973 DOI: 10.1016/s0079-6603(05)80003-0] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Sharon H Ackerman
- Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Duvezin-Caubet S, Caron M, Giraud MF, Velours J, di Rago JP. The two rotor components of yeast mitochondrial ATP synthase are mechanically coupled by subunit delta. Proc Natl Acad Sci U S A 2003; 100:13235-40. [PMID: 14581615 PMCID: PMC263764 DOI: 10.1073/pnas.2135169100] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The mitochondrial ATP synthase is made of a membrane-integrated F0 component that forms a proton-permeable pore through the inner membrane and a globular peripheral F1 domain where ATP is synthesized. The catalytic mechanism is thought to involve the rotation of a 10-12 c subunit ring in the F0 together with the gamma subunit of F1. An important and not yet resolved question is to define precisely how the gamma subunit is connected with the c-ring. In this study, using a doxycycline-regulatable expression system, we provide direct evidence that the rest of the enzyme can assemble without the delta subunit of F1, and we show that delta-less mitochondria are uncoupled because of an F0-mediated proton leak. Based on these observations, and taking into account high-resolution structural models, we propose that subunit delta plays a key role in the mechanical coupling of the c-ring to subunit gamma.
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Affiliation(s)
- Stéphane Duvezin-Caubet
- Institut de Biochimie et Génétique Cellulaires du Centre National de la Recherche Scientifique, Université Victor Segalen, 1 Rue Camille Saint-Saëns, Bordeaux 33077 Cedex, France
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43
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Current awareness on yeast. Yeast 2003; 20:837-44. [PMID: 12886942 DOI: 10.1002/yea.946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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