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Usey MM, Ruberto AA, Huet D. The Toxoplasma gondii homolog of ATPase inhibitory factor 1 is critical for mitochondrial cristae maintenance and stress response. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.09.607411. [PMID: 39149366 PMCID: PMC11326266 DOI: 10.1101/2024.08.09.607411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
The production of energy in the form of ATP by the mitochondrial ATP synthase must be tightly controlled. One well-conserved form of regulation is mediated via ATPase inhibitory factor 1 (IF1), which governs ATP synthase activity and gene expression patterns through a cytoprotective process known as mitohormesis. In apicomplexans, the processes regulating ATP synthase activity are not fully elucidated. Using the model apicomplexan Toxoplasma gondii, we found that knockout and overexpression of TgIF1, the structural homolog of IF1, significantly affected gene expression. Additionally, TgIF1 overexpression resulted in the formation of a stable TgIF1 oligomer that increased the presence of higher order ATP synthase oligomers. We also show that parasites lacking TgIF1 exhibit reduced mitochondrial cristae density, and that while TgIF1 levels do not affect growth in conventional culture conditions, they are crucial for parasite survival under hypoxia. Interestingly, TgIF1 overexpression enhances recovery from oxidative stress, suggesting a mitohormetic function. In summary, while TgIF1 does not appear to play a role in metabolic regulation under conventional growth conditions, our work highlights its importance for adapting to stressors faced by T. gondii and other apicomplexans throughout their intricate life cycles.
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Affiliation(s)
- Madelaine M. Usey
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Anthony A. Ruberto
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
- Institute of Bioinformatics, University of Georgia, Athens, GA, USA
| | - Diego Huet
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
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2
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Nan K, Zhong Z, Yue Y, Zhou W, Sun X, Shen Y, Qu M, Chen Z, Gu J, Sun C, Sun X, Lu L, Zhang J, Miao C, Sun M. HSK3486 Inhibits Colorectal Cancer Growth by Promoting Oxidative Stress and ATPase Inhibitory Factor 1 Activation. Dig Dis Sci 2024; 69:1214-1227. [PMID: 38376789 DOI: 10.1007/s10620-023-08213-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 11/24/2023] [Indexed: 02/21/2024]
Abstract
BACKGROUND HSK3486 (ciprofol), a new candidate drug similar to propofol, exerts sedative and hypnotic effects through gamma-aminobutyric acid type A receptors; however, its potential role in colorectal cancer is currently unknown. AIMS This study aimed to evaluate the effects of HSK3486 on colorectal cancer cell proliferation. METHODS Imaging was performed to detect reactive oxygen species and mitochondrial membrane potential. Western blotting was used to determine the expression of target signals. The HSK3486 molecular mechanism was investigated through ATPase inhibitory factor 1 knockdown and xenograft model experiments to assess mitochondrial function in colorectal cancer cells. RESULTS Cell Counting Kit-8 and Annexin V/propidium iodide double staining assays showed that HSK3486 inhibited colorectal cancer cell proliferation in a concentration-dependent manner. In addition, HSK3486 treatment increased the expression of B-cell lymphoma-2-associated X, cleaved caspase 3, and cleaved poly (ADP-ribose) polymerase, whereas myeloid cell leukemia-1 and B-cell lymphoma 2 expression decreased. HSK3486 promoted mitochondrial dysfunction by inducing ATPase inhibitor factor 1 expression. Furthermore, HSK3486 promoted oxidative stress, as shown by the increase in reactive oxygen species and lactate dehydrogenase levels, along with a decrease in mitochondrial membrane potential and ATP levels. ATPase inhibitor factor 1 small interfering RNA pretreatment dramatically increased the mitochondrial membrane potential and tumor size in a xenograft model following exposure to HSK3486. CONCLUSION Collectively, our findings revealed that HSK3486 induces oxidative stress, resulting in colorectal cancer cell apoptosis, making it a potential candidate therapeutic strategy for colorectal cancer.
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Affiliation(s)
- Ke Nan
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Ziwen Zhong
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Ying Yue
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Wenchang Zhou
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Xingfeng Sun
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
- Department of Anesthesiology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, 200438, China
| | - Yang Shen
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Mengdi Qu
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Zhaoyuan Chen
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Jiahui Gu
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Caihong Sun
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Xun Sun
- Department of Medical Oncology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Lihong Lu
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
- Department of Anesthesiology, Department of Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Jie Zhang
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Changhong Miao
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China
| | - Minli Sun
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, No.180 Feng-Lin Road, Shanghai, 200032, China.
- Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
- Shanghai Key Laboratory of Perioperative Stress and Protection, Shanghai, China.
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3
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Gore E, Duparc T, Genoux A, Perret B, Najib S, Martinez LO. The Multifaceted ATPase Inhibitory Factor 1 (IF1) in Energy Metabolism Reprogramming and Mitochondrial Dysfunction: A New Player in Age-Associated Disorders? Antioxid Redox Signal 2022; 37:370-393. [PMID: 34605675 PMCID: PMC9398489 DOI: 10.1089/ars.2021.0137] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Significance: The mitochondrial oxidative phosphorylation (OXPHOS) system, comprising the electron transport chain and ATP synthase, generates membrane potential, drives ATP synthesis, governs energy metabolism, and maintains redox balance. OXPHOS dysfunction is associated with a plethora of diseases ranging from rare inherited disorders to common conditions, including diabetes, cancer, neurodegenerative diseases, as well as aging. There has been great interest in studying regulators of OXPHOS. Among these, ATPase inhibitory factor 1 (IF1) is an endogenous inhibitor of ATP synthase that has long been thought to avoid the consumption of cellular ATP when ATP synthase acts as an ATP hydrolysis enzyme. Recent Advances: Recent data indicate that IF1 inhibits ATP synthesis and is involved in a multitude of mitochondrial-related functions, such as mitochondrial quality control, energy metabolism, redox balance, and cell fate. IF1 also inhibits the ATPase activity of cell-surface ATP synthase, and it is used as a cardiovascular disease biomarker. Critical Issues: Although recent data have led to a paradigm shift regarding IF1 functions, these have been poorly studied in entire organisms and in different organs. The understanding of the cellular biology of IF1 is, therefore, still limited. The aim of this review was to provide an overview of the current understanding of the role of IF1 in mitochondrial functions, health, and diseases. Future Directions: Further investigations of IF1 functions at the cell, organ, and whole-organism levels and in different pathophysiological conditions will help decipher the controversies surrounding its involvement in mitochondrial function and could unveil therapeutic strategies in human pathology. Antioxid. Redox Signal. 37, 370-393.
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Affiliation(s)
- Emilia Gore
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | - Thibaut Duparc
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | - Annelise Genoux
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France.,Service de Biochimie, Pôle de biologie, Hôpital de Purpan, CHU de Toulouse, Toulouse, France
| | - Bertrand Perret
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France.,Service de Biochimie, Pôle de biologie, Hôpital de Purpan, CHU de Toulouse, Toulouse, France
| | - Souad Najib
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
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Ukolova IV, Kondakova MA, Kondratov IG, Sidorov AV, Borovskii GB, Voinikov VK. New insights into the organisation of the oxidative phosphorylation system in the example of pea shoot mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2020; 1861:148264. [PMID: 32663476 DOI: 10.1016/j.bbabio.2020.148264] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/20/2020] [Accepted: 07/06/2020] [Indexed: 12/17/2022]
Abstract
The physical and functional organisation of the OXPHOS system in mitochondria in vivo remains elusive. At present, different models of OXPHOS arrangement, representing either highly ordered respiratory strings or, vice versa, a set of randomly dispersed supercomplexes and respiratory complexes, have been suggested. In the present study, we examined a supramolecular arrangement of the OXPHOS system in pea shoot mitochondria using digitonin solubilisation of its constituents, which were further analysed by classical BN-related techniques and a multidimensional gel electrophoresis system when required. As a result, in addition to supercomplexes I1III2, I1III2IVn and III2IV1-2, dimer V2, and individual complexes I-V previously detected in plant mitochondria, new OXPHOS structures were also revealed. Of them, (1) a megacomplex (IIxIIIyIVz)n including complex II, (2) respirasomes I2III4IVn with two copies of complex I and dimeric complex III2, (3) a minor new supercomplex IV1Va2 comigrating with I1III2, and (4) a second minor form of ATP synthase, Va, were found. The activity of singular complexes I, IV, and V was higher than the activity of the associated forms. The detection of new supercomplex IV1Va2, along with assemblies I1III2 and I1-2III2-4IVn, prompted us to suggest the occurrence of in vivo oxphosomes comprising complexes I, III2, IV, and V. The putative oxphosome's stoichiometry, historical background, assumed functional significance, and subcompartmental location are discussed herein.
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Affiliation(s)
- Irina V Ukolova
- Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov St., Irkutsk 664033, Russia.
| | - Marina A Kondakova
- Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov St., Irkutsk 664033, Russia
| | - Ilya G Kondratov
- Limnological Institute SB RAS, 3, Ulan-Batorskaya St., Irkutsk 664033, Russia
| | - Alexander V Sidorov
- Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov St., Irkutsk 664033, Russia; Irkutsk State Medical University, 1, Krasnogo Vosstaniya St., Irkutsk 664003, Russia
| | - Gennadii B Borovskii
- Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov St., Irkutsk 664033, Russia
| | - Victor K Voinikov
- Siberian Institute of Plant Physiology and Biochemistry SB RAS, 132, Lermontov St., Irkutsk 664033, Russia
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5
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The relevance of the supramolecular arrangements of the respiratory chain complexes in human diseases and aging. Mitochondrion 2019; 47:266-272. [PMID: 30664953 DOI: 10.1016/j.mito.2019.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 07/16/2018] [Accepted: 01/03/2019] [Indexed: 01/12/2023]
Abstract
Mitochondrial dysfunction, a common factor in several diseases is accompanied with reactive oxygen species (ROS) production. These molecules react with proteins and lipids at their site of generation, establishing a vicious cycle which might result in further mitochondrial injury. It is well established that mitochondrial respiratory complexes can be organized into supramolecular structures called supercomplexes (SCs) or respirasomes; yet, the physiological/pathological relevance of these structures remains unresolved. Changes in their stabilization and content have been documented in Barth's syndrome, degenerative diseases such as Parkinson's and Alzheimer, cardiovascular diseases including heart failure and ischemia-reperfusion damage, as well as in aging. Under pathological conditions, SCs stability could have relevant biomedical implications or might be used as a reliable marker of mitochondrial damage. The purpose of this review is to recapitulate the current state of the significance on mitochondrial bioenergetics of these structures and their possible role in pathophysiologies related with ROS increase.
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6
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Nesci S, Trombetti F, Ventrella V, Pagliarani A. From the Ca 2+-activated F 1F O-ATPase to the mitochondrial permeability transition pore: an overview. Biochimie 2018; 152:85-93. [PMID: 29964086 DOI: 10.1016/j.biochi.2018.06.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/26/2018] [Indexed: 01/02/2023]
Abstract
Based on recent advances on the Ca2+-activated F1FO-ATPase features, a novel multistep mechanism involving the mitochondrial F1FO complex in the formation and opening of the still enigmatic mitochondrial permeability transition pore (MPTP), is proposed. MPTP opening makes the inner mitochondrial membrane (IMM) permeable to ions and solutes and, through cascade events, addresses cell fate to death. Since MPTP forms when matrix Ca2+ concentration rises and ATP is hydrolyzed by the F1FO-ATPase, conformational changes, triggered by Ca2+ insertion in F1, may be transmitted to FO and locally modify the IMM curvature. These events would cause F1FO-ATPase dimer dissociation and MPTP opening.
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Affiliation(s)
- Salvatore Nesci
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
| | - Fabiana Trombetti
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
| | - Vittoria Ventrella
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy
| | - Alessandra Pagliarani
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064, Ozzano Emilia, BO, Italy.
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7
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Esparza-Perusquía M, Olvera-Sánchez S, Pardo JP, Mendoza-Hernández G, Martínez F, Flores-Herrera O. Structural and kinetics characterization of the F 1F 0-ATP synthase dimer. New repercussion of monomer-monomer contact. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1858:975-981. [PMID: 28919501 DOI: 10.1016/j.bbabio.2017.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 08/24/2017] [Accepted: 09/12/2017] [Indexed: 12/20/2022]
Abstract
Ustilago maydis is an aerobic basidiomycete that fully depends on oxidative phosphorylation for its supply of ATP, pointing to mitochondria as a key player in the energy metabolism of this organism. Mitochondrial F1F0-ATP synthase occurs in supramolecular structures. In this work, we isolated the monomer (640kDa) and the dimer (1280kDa) and characterized their subunit composition and kinetics of ATP hydrolysis. Mass spectrometry revealed that dimerizing subunits e and g were present in the dimer but not in the monomer. Analysis of the ATPase activity showed that both oligomers had Michaelis-Menten kinetics, but the dimer was 7 times more active than the monomer, while affinities were similar. The dimer was more sensitive to oligomycin inhibition, with a Ki of 24nM, while the monomer had a Ki of 169nM. The results suggest that the interphase between the monomers in the dimer state affects the catalytic efficiency of the enzyme and its sensitivity to inhibitors.
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Affiliation(s)
- Mercedes Esparza-Perusquía
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México City, México
| | - Sofía Olvera-Sánchez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México City, México
| | - Juan Pablo Pardo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México City, México
| | - Guillermo Mendoza-Hernández
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México City, México
| | - Federico Martínez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México City, México
| | - Oscar Flores-Herrera
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México City, México.
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8
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Esparza-Moltó PB, Nuevo-Tapioles C, Cuezva JM. Regulation of the H +-ATP synthase by IF1: a role in mitohormesis. Cell Mol Life Sci 2017; 74:2151-2166. [PMID: 28168445 PMCID: PMC5425498 DOI: 10.1007/s00018-017-2462-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/09/2017] [Accepted: 01/10/2017] [Indexed: 01/18/2023]
Abstract
The mitochondrial H+-ATP synthase is a primary hub of cellular homeostasis by providing the energy required to sustain cellular activity and regulating the production of signaling molecules that reprogram nuclear activity needed for adaption to changing cues. Herein, we summarize findings regarding the regulation of the activity of the H+-ATP synthase by its physiological inhibitor, the ATPase inhibitory factor 1 (IF1) and their functional role in cellular homeostasis. First, we outline the structure and the main molecular mechanisms that regulate the activity of the enzyme. Next, we describe the molecular biology of IF1 and summarize the regulation of IF1 expression and activity as an inhibitor of the H+-ATP synthase emphasizing the role of IF1 as a main driver of energy rewiring and cellular signaling in cancer. Findings in transgenic mice in vivo indicate that the overexpression of IF1 is sufficient to reprogram energy metabolism to an enhanced glycolysis and activate reactive oxygen species (ROS)-dependent signaling pathways that promote cell survival. These findings are placed in the context of mitohormesis, a program in which a mild mitochondrial stress triggers adaptive cytoprotective mechanisms that improve lifespan. In this regard, we emphasize the role played by the H+-ATP synthase in modulating signaling pathways that activate the mitohormetic response, namely ATP, ROS and target of rapamycin (TOR). Overall, we aim to highlight the relevant role of the H+-ATP synthase and of IF1 in cellular physiology and the need of additional studies to decipher their contributions to aging and age-related diseases.
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Affiliation(s)
- Pau B Esparza-Moltó
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Cristina Nuevo-Tapioles
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - José M Cuezva
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
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9
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Faccenda D, Nakamura J, Gorini G, Dhoot GK, Piacentini M, Yoshida M, Campanella M. Control of Mitochondrial Remodeling by the ATPase Inhibitory Factor 1 Unveils a Pro-survival Relay via OPA1. Cell Rep 2017; 18:1869-1883. [PMID: 28228254 DOI: 10.1016/j.celrep.2017.01.070] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 12/01/2016] [Accepted: 01/23/2017] [Indexed: 12/31/2022] Open
Abstract
The ubiquitously expressed ATPase inhibitory factor 1 (IF1) is a mitochondrial protein that blocks the reversal of the F1Fo-ATPsynthase, preventing dissipation of cellular ATP and ischemic damage. IF1 suppresses programmed cell death, enhancing tumor invasion and chemoresistance, and is expressed in various types of human cancers. In this study, we examined its effect on mitochondrial redox balance and apoptotic cristae remodeling, finding that, by maintaining ATP levels, IF1 reduces glutathione (GSH) consumption and inactivation of peroxiredoxin 3 (Prx3) during apoptosis. This correlates with inhibition of metallopeptidase OMA1-mediated processing of the pro-fusion dynamin-related protein optic atrophy 1 (OPA1). Stabilization of OPA1 impedes cristae remodeling and completion of apoptosis. Taken together, these data suggest that IF1 acts on both mitochondrial bioenergetics and structure, is involved in mitochondrial signaling in tumor cells, and may underlie their proliferative capacity.
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Affiliation(s)
- Danilo Faccenda
- Department of Comparative Biomedical Sciences, The Royal Veterinary College London and UCL Consortium for Mitochondrial Research, Royal College Street, NW1 0TU London, UK; Department of Biology, University of Rome "Tor Vergata," 00133 Rome, Italy
| | - Junji Nakamura
- Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto 603-8555, Japan
| | - Giulia Gorini
- Department of Comparative Biomedical Sciences, The Royal Veterinary College London and UCL Consortium for Mitochondrial Research, Royal College Street, NW1 0TU London, UK
| | - Gurtej K Dhoot
- Department of Comparative Biomedical Sciences, The Royal Veterinary College London and UCL Consortium for Mitochondrial Research, Royal College Street, NW1 0TU London, UK
| | - Mauro Piacentini
- Department of Biology, University of Rome "Tor Vergata," 00133 Rome, Italy; National Institute for Infectious Diseases, IRCCS "Lazzaro Spallanzani," Rome, Italy
| | - Masusuke Yoshida
- Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto 603-8555, Japan
| | - Michelangelo Campanella
- Department of Comparative Biomedical Sciences, The Royal Veterinary College London and UCL Consortium for Mitochondrial Research, Royal College Street, NW1 0TU London, UK; Department of Biology, University of Rome "Tor Vergata," 00133 Rome, Italy.
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10
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Allen-Worthington K, Xie J, Brown JL, Edmunson AM, Dowling A, Navratil AM, Scavelli K, Yoon H, Kim DG, Bynoe MS, Clarke I, Roberson MS. The F0F1 ATP Synthase Complex Localizes to Membrane Rafts in Gonadotrope Cells. Mol Endocrinol 2016; 30:996-1011. [PMID: 27482602 PMCID: PMC5414608 DOI: 10.1210/me.2015-1324] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 07/29/2016] [Indexed: 12/22/2022] Open
Abstract
Fertility in mammals requires appropriate communication within the hypothalamic-pituitary-gonadal axis and the GnRH receptor (GnRHR) is a central conduit for this communication. The GnRHR resides in discrete membrane rafts and raft occupancy is required for signaling by GnRH. The present studies use immunoprecipitation and mass spectrometry to define peptides present within the raft associated with the GnRHR and flotillin-1, a key raft marker. These studies revealed peptides from the F0F1 ATP synthase complex. The catalytic subunits of the F1 domain were validated by immunoprecipitation, flow cytometry, and cell surface biotinylation studies demonstrating that this complex was present at the plasma membrane associated with the GnRHR. The F1 catalytic domain faces the extracellular space and catalyzes ATP synthesis when presented with ADP in normal mouse pituitary explants and a gonadotrope cell line. Steady-state extracellular ATP accumulation was blunted by coadministration of inhibitory factor 1, limiting inorganic phosphate in the media, and by chronic stimulation of the GnRHR. Steady-state extracellular ATP accumulation was enhanced by pharmacological inhibition of ecto-nucleoside triphosphate diphosphohydrolases. Kisspeptin administration induced coincident GnRH and ATP release from the median eminence into the hypophyseal-portal vasculature in ovariectomized sheep. Elevated levels of extracellular ATP augmented GnRH-induced secretion of LH from pituitary cells in primary culture, which was blocked in media containing low inorganic phosphate supporting the importance of extracellular ATP levels to gonadotrope cell function. These studies indicate that gonadotropes have intrinsic ability to metabolize ATP in the extracellular space and extracellular ATP may serve as a modulator of GnRH-induced LH secretion.
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Affiliation(s)
- Krystal Allen-Worthington
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Jianjun Xie
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Jessica L Brown
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Alexa M Edmunson
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Abigail Dowling
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Amy M Navratil
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Kurt Scavelli
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Hojean Yoon
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Do-Geun Kim
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Margaret S Bynoe
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Iain Clarke
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Mark S Roberson
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
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11
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García-Bermúdez J, Cuezva JM. The ATPase Inhibitory Factor 1 (IF1): A master regulator of energy metabolism and of cell survival. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1857:1167-1182. [PMID: 26876430 DOI: 10.1016/j.bbabio.2016.02.004] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 01/28/2016] [Accepted: 02/07/2016] [Indexed: 12/19/2022]
Abstract
In this contribution we summarize most of the findings reported for the molecular and cellular biology of the physiological inhibitor of the mitochondrial H(+)-ATP synthase, the engine of oxidative phosphorylation (OXPHOS) and gate of cell death. We first describe the structure and major mechanisms and molecules that regulate the activity of the ATP synthase placing the ATPase Inhibitory Factor 1 (IF1) as a major determinant in the regulation of the activity of the ATP synthase and hence of OXPHOS. Next, we summarize the post-transcriptional mechanisms that regulate the expression of IF1 and emphasize, in addition to the regulation afforded by the protonation state of histidine residues, that the activity of IF1 as an inhibitor of the ATP synthase is also regulated by phosphorylation of a serine residue. Phosphorylation of S39 in IF1 by the action of a mitochondrial cAMP-dependent protein kinase A hampers its interaction with the ATP synthase, i.e., only dephosphorylated IF1 interacts with the enzyme. Upon IF1 interaction with the ATP synthase both the synthetic and hydrolytic activities of the engine of OXPHOS are inhibited. These findings are further placed into the physiological context to stress the emerging roles played by IF1 in metabolic reprogramming in cancer, in hypoxia and in cellular differentiation. We review also the implication of IF1 in other cellular situations that involve the malfunctioning of mitochondria. Special emphasis is given to the role of IF1 as driver of the generation of a reactive oxygen species signal that, emanating from mitochondria, is able to reprogram the nucleus of the cell to confer by various signaling pathways a cell-death resistant phenotype against oxidative stress. Overall, our intention is to highlight the urgent need of further investigations in the molecular and cellular biology of IF1 and of its target, the ATP synthase, to unveil new therapeutic strategies in human pathology. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.
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Affiliation(s)
- Javier García-Bermúdez
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - José M Cuezva
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
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12
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Le Breton N, Adrianaivomananjaona T, Gerbaud G, Etienne E, Bisetto E, Dautant A, Guigliarelli B, Haraux F, Martinho M, Belle V. Dimerization interface and dynamic properties of yeast IF1 revealed by Site-Directed Spin Labeling EPR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1857:89-97. [PMID: 26518384 DOI: 10.1016/j.bbabio.2015.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/21/2015] [Accepted: 10/25/2015] [Indexed: 11/21/2022]
Abstract
The mitochondrial ATPase inhibitor, IF1, regulates the activity of the mitochondrial ATP synthase. The oligomeric state of IF1 related to pH is crucial for its inhibitory activity. Although extensive structural studies have been performed to characterize the oligomeric states of bovine IF1, only little is known concerning those of yeast IF1. While bovine IF1 can be found as an inhibitory dimer at low pH and a non-inhibitory tetramer at high pH, a monomer/dimer equilibrium has been described for yeast IF1, high pH values favoring the monomeric state. Combining different strategies involving the grafting of nitroxide spin labels combined with Electron Paramagnetic Resonance (EPR) spectroscopy, the present study brings the first structural characterization, at the residue level, of yeast IF1 in its dimeric form. The results show that the dimerization interface involves the central region of the peptide revealing that the dimer corresponds to a non-inhibitory state. Moreover, we demonstrate that the C-terminal region of the peptide is highly dynamic and that this segment is probably folded back onto the central region. Finally, the pH-dependence of the inter-label distance distribution has been observed indicating a conformational change between two structural states in the dimer.
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Affiliation(s)
- Nolwenn Le Breton
- Aix-Marseille Université, CNRS, BIP UMR 7281, 31 chemin J. Aiguier, F-13402 Marseille, France
| | - Tiona Adrianaivomananjaona
- Lifesearch, 72 rue du Fauboug St Honoré, F-75008 Paris, France; CEA, Institut de Biologie et de Technologies de Saclay IBITECS, SB2SM, F-91191 Gif sur Yvette, France; CEA, CNRS, Université Paris Sud, Institut de Biologie Intégrative de la Cellule I2BC, UMR 9198, F-91191 Gif sur Yvette, France
| | - Guillaume Gerbaud
- Aix-Marseille Université, CNRS, BIP UMR 7281, 31 chemin J. Aiguier, F-13402 Marseille, France
| | - Emilien Etienne
- Aix-Marseille Université, CNRS, BIP UMR 7281, 31 chemin J. Aiguier, F-13402 Marseille, France
| | - Elena Bisetto
- CEA, Institut de Biologie et de Technologies de Saclay IBITECS, SB2SM, F-91191 Gif sur Yvette, France; Department of Biomedical Sciences and Technologies, University of Udine, Piazzale Kolbe 4, I-33100 Udine, Italy
| | - Alain Dautant
- University Bordeaux-CNRS, IBGC, UMR 5095, 1 rue Camille Saint-Saëns, F-33000 Bordeaux, France
| | - Bruno Guigliarelli
- Aix-Marseille Université, CNRS, BIP UMR 7281, 31 chemin J. Aiguier, F-13402 Marseille, France
| | - Francis Haraux
- CEA, Institut de Biologie et de Technologies de Saclay IBITECS, SB2SM, F-91191 Gif sur Yvette, France; CEA, CNRS, Université Paris Sud, Institut de Biologie Intégrative de la Cellule I2BC, UMR 9198, F-91191 Gif sur Yvette, France.
| | - Marlène Martinho
- Aix-Marseille Université, CNRS, BIP UMR 7281, 31 chemin J. Aiguier, F-13402 Marseille, France
| | - Valérie Belle
- Aix-Marseille Université, CNRS, BIP UMR 7281, 31 chemin J. Aiguier, F-13402 Marseille, France.
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13
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Bernardi P, Rasola A, Forte M, Lippe G. The Mitochondrial Permeability Transition Pore: Channel Formation by F-ATP Synthase, Integration in Signal Transduction, and Role in Pathophysiology. Physiol Rev 2015; 95:1111-55. [PMID: 26269524 DOI: 10.1152/physrev.00001.2015] [Citation(s) in RCA: 420] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The mitochondrial permeability transition (PT) is a permeability increase of the inner mitochondrial membrane mediated by a channel, the permeability transition pore (PTP). After a brief historical introduction, we cover the key regulatory features of the PTP and provide a critical assessment of putative protein components that have been tested by genetic analysis. The discovery that under conditions of oxidative stress the F-ATP synthases of mammals, yeast, and Drosophila can be turned into Ca(2+)-dependent channels, whose electrophysiological properties match those of the corresponding PTPs, opens new perspectives to the field. We discuss structural and functional features of F-ATP synthases that may provide clues to its transition from an energy-conserving into an energy-dissipating device as well as recent advances on signal transduction to the PTP and on its role in cellular pathophysiology.
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Affiliation(s)
- Paolo Bernardi
- Department of Biomedical Sciences and Consiglio Nazionale delle Ricerche Neuroscience Institute, University of Padova, Padova, Italy; Vollum Institute, Oregon Health and Sciences University, Portland, Oregon; and Department of Food Science, University of Udine, Udine, Italy
| | - Andrea Rasola
- Department of Biomedical Sciences and Consiglio Nazionale delle Ricerche Neuroscience Institute, University of Padova, Padova, Italy; Vollum Institute, Oregon Health and Sciences University, Portland, Oregon; and Department of Food Science, University of Udine, Udine, Italy
| | - Michael Forte
- Department of Biomedical Sciences and Consiglio Nazionale delle Ricerche Neuroscience Institute, University of Padova, Padova, Italy; Vollum Institute, Oregon Health and Sciences University, Portland, Oregon; and Department of Food Science, University of Udine, Udine, Italy
| | - Giovanna Lippe
- Department of Biomedical Sciences and Consiglio Nazionale delle Ricerche Neuroscience Institute, University of Padova, Padova, Italy; Vollum Institute, Oregon Health and Sciences University, Portland, Oregon; and Department of Food Science, University of Udine, Udine, Italy
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14
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Bernardi P, Di Lisa F, Fogolari F, Lippe G. From ATP to PTP and Back: A Dual Function for the Mitochondrial ATP Synthase. Circ Res 2015; 116:1850-62. [PMID: 25999424 DOI: 10.1161/circresaha.115.306557] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mitochondria not only play a fundamental role in heart physiology but are also key effectors of dysfunction and death. This dual role assumes a new meaning after recent advances on the nature and regulation of the permeability transition pore, an inner membrane channel whose opening requires matrix Ca(2+) and is modulated by many effectors including reactive oxygen species, matrix cyclophilin D, Pi (inorganic phosphate), and matrix pH. The recent demonstration that the F-ATP synthase can reversibly undergo a Ca(2+)-dependent transition to form a channel that mediates the permeability transition opens new perspectives to the field. These findings demand a reassessment of the modifications of F-ATP synthase that take place in the heart under pathological conditions and of their potential role in determining the transition of F-ATP synthase from and energy-conserving into an energy-dissipating device.
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Affiliation(s)
- Paolo Bernardi
- From the Department of Biomedical Sciences, University of Padova, Italy (P.B., F.D.L.); and Department of Medical and Biological Sciences (F.F) and Department of Food Science (G.L.), University of Udine, Udine, Italy.
| | - Fabio Di Lisa
- From the Department of Biomedical Sciences, University of Padova, Italy (P.B., F.D.L.); and Department of Medical and Biological Sciences (F.F) and Department of Food Science (G.L.), University of Udine, Udine, Italy
| | - Federico Fogolari
- From the Department of Biomedical Sciences, University of Padova, Italy (P.B., F.D.L.); and Department of Medical and Biological Sciences (F.F) and Department of Food Science (G.L.), University of Udine, Udine, Italy
| | - Giovanna Lippe
- From the Department of Biomedical Sciences, University of Padova, Italy (P.B., F.D.L.); and Department of Medical and Biological Sciences (F.F) and Department of Food Science (G.L.), University of Udine, Udine, Italy
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15
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Barbato S, Sgarbi G, Gorini G, Baracca A, Solaini G. The inhibitor protein (IF1) of the F1F0-ATPase modulates human osteosarcoma cell bioenergetics. J Biol Chem 2015; 290:6338-48. [PMID: 25605724 PMCID: PMC4358270 DOI: 10.1074/jbc.m114.631788] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/20/2015] [Indexed: 01/20/2023] Open
Abstract
The bioenergetics of IF1 transiently silenced cancer cells has been extensively investigated, but the role of IF1 (the natural inhibitor protein of F1F0-ATPase) in cancer cell metabolism is still uncertain. To shed light on this issue, we established a method to prepare stably IF1-silenced human osteosarcoma clones and explored the bioenergetics of IF1 null cancer cells. We showed that IF1-silenced cells proliferate normally, consume glucose, and release lactate as controls do, and contain a normal steady-state ATP level. However, IF1-silenced cells displayed an enhanced steady-state mitochondrial membrane potential and consistently showed a reduced ADP-stimulated respiration rate. In the parental cells (i.e. control cells containing IF1) the inhibitor protein was found to be associated with the dimeric form of the ATP synthase complex, therefore we propose that the interaction of IF1 with the complex either directly, by increasing the catalytic activity of the enzyme, or indirectly, by improving the structure of mitochondrial cristae, can increase the oxidative phosphorylation rate in osteosarcoma cells grown under normoxic conditions.
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Affiliation(s)
- Simona Barbato
- From the Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Gianluca Sgarbi
- From the Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Giulia Gorini
- From the Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Alessandra Baracca
- From the Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Giancarlo Solaini
- From the Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
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16
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Martínez-Reyes I, Cuezva JM. The H+-ATP synthase: A gate to ROS-mediated cell death or cell survival. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1099-112. [DOI: 10.1016/j.bbabio.2014.03.010] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 03/03/2014] [Accepted: 03/19/2014] [Indexed: 12/13/2022]
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17
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Antoniel M, Giorgio V, Fogolari F, Glick GD, Bernardi P, Lippe G. The oligomycin-sensitivity conferring protein of mitochondrial ATP synthase: emerging new roles in mitochondrial pathophysiology. Int J Mol Sci 2014; 15:7513-36. [PMID: 24786291 PMCID: PMC4057687 DOI: 10.3390/ijms15057513] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 04/18/2014] [Accepted: 04/21/2014] [Indexed: 01/08/2023] Open
Abstract
The oligomycin-sensitivity conferring protein (OSCP) of the mitochondrial F(O)F1 ATP synthase has long been recognized to be essential for the coupling of proton transport to ATP synthesis. Located on top of the catalytic F1 sector, it makes stable contacts with both F1 and the peripheral stalk, ensuring the structural and functional coupling between F(O) and F1, which is disrupted by the antibiotic, oligomycin. Recent data have established that OSCP is the binding target of cyclophilin (CyP) D, a well-characterized inducer of the mitochondrial permeability transition pore (PTP), whose opening can precipitate cell death. CyPD binding affects ATP synthase activity, and most importantly, it decreases the threshold matrix Ca²⁺ required for PTP opening, in striking analogy with benzodiazepine 423, an apoptosis-inducing agent that also binds OSCP. These findings are consistent with the demonstration that dimers of ATP synthase generate Ca²⁺-dependent currents with features indistinguishable from those of the PTP and suggest that ATP synthase is directly involved in PTP formation, although the underlying mechanism remains to be established. In this scenario, OSCP appears to play a fundamental role, sensing the signal(s) that switches the enzyme of life in a channel able to precipitate cell death.
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Affiliation(s)
- Manuela Antoniel
- Department of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B, 35121 Padua, Italy.
| | - Valentina Giorgio
- Department of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B, 35121 Padua, Italy.
| | - Federico Fogolari
- Department of Biomedical Sciences, University of Udine, p.le Kolbe, 33100 Udine, Italy.
| | - Gary D Glick
- Department of Chemistry, Graduate Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Paolo Bernardi
- Department of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B, 35121 Padua, Italy.
| | - Giovanna Lippe
- Department of Food Science, University of Udine, via Sondrio 2/A, 33100 Udine, Italy.
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18
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Formentini L, Pereira MP, Sánchez-Cenizo L, Santacatterina F, Lucas JJ, Navarro C, Martínez-Serrano A, Cuezva JM. In vivo inhibition of the mitochondrial H+-ATP synthase in neurons promotes metabolic preconditioning. EMBO J 2014; 33:762-78. [PMID: 24521670 PMCID: PMC4000092 DOI: 10.1002/embj.201386392] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 01/08/2014] [Accepted: 01/13/2014] [Indexed: 12/25/2022] Open
Abstract
A key transducer in energy conservation and signaling cell death is the mitochondrial H(+)-ATP synthase. The expression of the ATPase inhibitory factor 1 (IF1) is a strategy used by cancer cells to inhibit the activity of the H(+)-ATP synthase to generate a ROS signal that switches on cellular programs of survival. We have generated a mouse model expressing a mutant of human IF1 in brain neurons to assess the role of the H(+)-ATP synthase in cell death in vivo. The expression of hIF1 inhibits the activity of oxidative phosphorylation and mediates the shift of neurons to an enhanced aerobic glycolysis. Metabolic reprogramming induces brain preconditioning affording protection against quinolinic acid-induced excitotoxicity. Mechanistically, preconditioning involves the activation of the Akt/p70S6K and PARP repair pathways and Bcl-xL protection from cell death. Overall, our findings provide the first in vivo evidence highlighting the H(+)-ATP synthase as a target to prevent neuronal cell death.
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Affiliation(s)
- Laura Formentini
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIIIMadrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de MadridMadrid, Spain
| | - Marta P Pereira
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
| | - Laura Sánchez-Cenizo
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIIIMadrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de MadridMadrid, Spain
| | - Fulvio Santacatterina
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIIIMadrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de MadridMadrid, Spain
| | - José J Lucas
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), ISCIIIMadrid, Spain
| | - Carmen Navarro
- Departamento de Patología y Neuropatología, Instituto de Investigación Biomédica de Vigo (IBIV)Vigo, Spain
| | - Alberto Martínez-Serrano
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
| | - José M Cuezva
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM)Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIIIMadrid, Spain
- Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de MadridMadrid, Spain
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19
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Habersetzer J, Larrieu I, Priault M, Salin B, Rossignol R, Brèthes D, Paumard P. Human F1F0 ATP synthase, mitochondrial ultrastructure and OXPHOS impairment: a (super-)complex matter? PLoS One 2013; 8:e75429. [PMID: 24098383 PMCID: PMC3788808 DOI: 10.1371/journal.pone.0075429] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 08/14/2013] [Indexed: 01/18/2023] Open
Abstract
Mitochondrial morphogenesis is a key process of cell physiology. It is essential for the proper function of this double membrane-delimited organelle, as it ensures the packing of the inner membrane in a very ordered pattern called cristae. In yeast, the mitochondrial ATP synthase is able to form dimers that can assemble into oligomers. Two subunits (e and g) are involved in this supramolecular organization. Deletion of the genes encoding these subunits has no effect on the ATP synthase monomer assembly or activity and only affects its dimerization and oligomerization. Concomitantly, the absence of subunits e and g and thus, of ATP synthase supercomplexes, promotes the modification of mitochondrial ultrastructure suggesting that ATP synthase oligomerization is involved in cristae morphogenesis. We report here that in mammalian cells in culture, the shRNA-mediated down-regulation of subunits e and g affects the stability of ATP synthase and results in a 50% decrease of the available functional enzyme. Comparable to what was shown in yeast, when subunits e and g expression are repressed, ATP synthase dimers and oligomers are less abundant when assayed by native electrophoresis. Unexpectedly, mammalian ATP synthase dimerization/oligomerization impairment has functional consequences on the respiratory chain leading to a decrease in OXPHOS activity. Finally these structural and functional alterations of the ATP synthase have a strong impact on the organelle itself leading to the fission of the mitochondrial network and the disorganization of mitochondrial ultrastructure. Unlike what was shown in yeast, the impairment of the ATP synthase oligomerization process drastically affects mitochondrial ATP production. Thus we propose that mutations or deletions of genes encoding subunits e and g may have physiopathological implications.
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Affiliation(s)
- Johann Habersetzer
- Laboratoire des Systèmes Transducteurs d'Energie et Morphologie Mitochondriale, Université Bordeaux Segalen, IBGC, UMR 5095, Bordeaux, France ; CNRS, IBGC, UMR 5095, Bordeaux, France
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20
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Nakamura J, Fujikawa M, Yoshida M. IF1, a natural inhibitor of mitochondrial ATP synthase, is not essential for the normal growth and breeding of mice. Biosci Rep 2013; 33:e00067. [PMID: 23889209 PMCID: PMC3775512 DOI: 10.1042/bsr20130078] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 07/24/2013] [Indexed: 11/17/2022] Open
Abstract
IF1 is an endogenous inhibitor protein of mitochondrial ATP synthase. It is evolutionarily conserved throughout all eukaryotes and it has been proposed to play crucial roles in prevention of the wasteful reverse reaction of ATP synthase, in the metabolic shift from oxidative phosphorylation to glycolysis, in the suppression of ROS (reactive oxygen species) generation, in mitochondria morphology and in haem biosynthesis in mitochondria, which leads to anaemia. Here, we report the phenotype of a mouse strain in which IF1 gene was destroyed. Unexpectedly, individuals of this IF1-KO (knockout) mouse strain grew and bred without defect. The general behaviours, blood test results and responses to starvation of the IF1-KO mice were apparently normal. There were no abnormalities in the tissue anatomy or the autophagy. Mitochondria of the IF1-KO mice were normal in morphology, in the content of ATP synthase molecules and in ATP synthesis activity. Thus, IF1 is not an essential protein for mice despite its ubiquitous presence in eukaryotes.
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Affiliation(s)
- Junji Nakamura
- *Department of Molecular Bioscience, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto 603-8555, Japan
- †International Cooperative Research Project (ICORP) ATP-Synthesis Regulation Project, Japan Science and Technology Agency (JST), 2-3-6 Aomi, Tokyo 135-0064, Japan
| | - Makoto Fujikawa
- †International Cooperative Research Project (ICORP) ATP-Synthesis Regulation Project, Japan Science and Technology Agency (JST), 2-3-6 Aomi, Tokyo 135-0064, Japan
- ‡Department of Biochemistry, Tokyo University of Science, 2641 Yamazaki, Noda 278-8510, Japan
| | - Masasuke Yoshida
- *Department of Molecular Bioscience, Kyoto Sangyo University, Kamigamo-Motoyama, Kyoto 603-8555, Japan
- †International Cooperative Research Project (ICORP) ATP-Synthesis Regulation Project, Japan Science and Technology Agency (JST), 2-3-6 Aomi, Tokyo 135-0064, Japan
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21
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Bernardi P. The mitochondrial permeability transition pore: a mystery solved? Front Physiol 2013; 4:95. [PMID: 23675351 PMCID: PMC3650560 DOI: 10.3389/fphys.2013.00095] [Citation(s) in RCA: 255] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 04/19/2013] [Indexed: 01/04/2023] Open
Abstract
The permeability transition (PT) denotes an increase of the mitochondrial inner membrane permeability to solutes with molecular masses up to about 1500 Da. It is presumed to be mediated by opening of a channel, the permeability transition pore (PTP), whose molecular nature remains a mystery. Here I briefly review the history of the PTP, discuss existing models, and present our new results indicating that reconstituted dimers of the FOF1 ATP synthase form a channel with properties identical to those of the mitochondrial megachannel (MMC), the electrophysiological equivalent of the PTP. Open questions remain, but there is now promise that the PTP can be studied by genetic methods to solve the large number of outstanding problems.
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Affiliation(s)
- Paolo Bernardi
- Department of Biomedical Sciences, University of Padova Padova, Italy
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22
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Bisetto E, Comelli M, Salzano AM, Picotti P, Scaloni A, Lippe G, Mavelli I. Proteomic analysis of F1F0-ATP synthase super-assembly in mitochondria of cardiomyoblasts undergoing differentiation to the cardiac lineage. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:807-16. [PMID: 23587863 DOI: 10.1016/j.bbabio.2013.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/28/2013] [Accepted: 04/05/2013] [Indexed: 02/06/2023]
Abstract
Mitochondria are essential organelles with multiple functions, especially in energy metabolism. An increasing number of data highlighted their role for cellular differentiation processes. We investigated differences in ATP synthase supra-molecular organization occurring in H9c2 cardiomyoblasts in the course of cardiac-like differentiation, along with ATP synthase biogenesis and maturation of mitochondrial cristae morphology. Using BN-PAGE analysis combined with one-step mild detergent extraction from mitochondria, a significant increase in dimer/monomer ratio was observed, indicating a distinct rise in the stability of the enzyme super-assembly. Remarkably, sub-stoichiometric mean values for ATP synthase subunit e were determined in both parental and cardiac-like H9c2 by an MS-based quantitative proteomics approach. This indicates a similar high proportion of complex molecules lacking subunit e in both cell types, and suggests a minor contribution of this component in the observed changes. 2D BN-PAGE/immunoblotting analysis and MS/MS analysis on single BN-PAGE band showed that the amount of inhibitor protein IF1 bound within the ATP synthase complexes increased in cardiac-like H9c2 and appeared greater in the dimer. In concomitance, a consistent improvement of enzyme activity, measured as both ATP synthesis and ATP hydrolysis rate, was observed, despite the increase of bound IF1 evocative of a greater inhibitory effect on the enzyme ATPase activity. The results suggest i) a role for IF1 in promoting dimer stabilization and super-assembly in H9c2 with physiological IF1 expression levels, likely unveiled by the fact that the contacts through accessory subunit e appear to be partially destabilized, ii) a link between dimer stabilization and enzyme activation.
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Affiliation(s)
- Elena Bisetto
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
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23
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Dimers of mitochondrial ATP synthase form the permeability transition pore. Proc Natl Acad Sci U S A 2013; 110:5887-92. [PMID: 23530243 DOI: 10.1073/pnas.1217823110] [Citation(s) in RCA: 706] [Impact Index Per Article: 64.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Here we define the molecular nature of the mitochondrial permeability transition pore (PTP), a key effector of cell death. The PTP is regulated by matrix cyclophilin D (CyPD), which also binds the lateral stalk of the FOF1 ATP synthase. We show that CyPD binds the oligomycin sensitivity-conferring protein subunit of the enzyme at the same site as the ATP synthase inhibitor benzodiazepine 423 (Bz-423), that Bz-423 sensitizes the PTP to Ca(2+) like CyPD itself, and that decreasing oligomycin sensitivity-conferring protein expression by RNAi increases the sensitivity of the PTP to Ca(2+). Purified dimers of the ATP synthase, which did not contain voltage-dependent anion channel or adenine nucleotide translocator, were reconstituted into lipid bilayers. In the presence of Ca(2+), addition of Bz-423 triggered opening of a channel with currents that were typical of the mitochondrial megachannel, which is the PTP electrophysiological equivalent. Channel openings were inhibited by the ATP synthase inhibitor AMP-PNP (γ-imino ATP, a nonhydrolyzable ATP analog) and Mg(2+)/ADP. These results indicate that the PTP forms from dimers of the ATP synthase.
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24
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Tasseva G, Bai HD, Davidescu M, Haromy A, Michelakis E, Vance JE. Phosphatidylethanolamine deficiency in Mammalian mitochondria impairs oxidative phosphorylation and alters mitochondrial morphology. J Biol Chem 2012; 288:4158-73. [PMID: 23250747 DOI: 10.1074/jbc.m112.434183] [Citation(s) in RCA: 250] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mitochondrial dysfunction is implicated in neurodegenerative, cardiovascular, and metabolic disorders, but the role of phospholipids, particularly the nonbilayer-forming lipid phosphatidylethanolamine (PE), in mitochondrial function is poorly understood. Elimination of mitochondrial PE (mtPE) synthesis via phosphatidylserine decarboxylase in mice profoundly alters mitochondrial morphology and is embryonic lethal (Steenbergen, R., Nanowski, T. S., Beigneux, A., Kulinski, A., Young, S. G., and Vance, J. E. (2005) J. Biol. Chem. 280, 40032-40040). We now report that moderate <30% depletion of mtPE alters mitochondrial morphology and function and impairs cell growth. Acute reduction of mtPE by RNAi silencing of phosphatidylserine decarboxylase and chronic reduction of mtPE in PSB-2 cells that have only 5% of normal phosphatidylserine synthesis decreased respiratory capacity, ATP production, and activities of electron transport chain complexes (C) I and CIV but not CV. Blue native-PAGE analysis revealed defects in the organization of CI and CIV into supercomplexes in PE-deficient mitochondria, correlated with reduced amounts of CI and CIV proteins. Thus, mtPE deficiency impairs formation and/or membrane integration of respiratory supercomplexes. Despite normal or increased levels of mitochondrial fusion proteins in mtPE-deficient cells, and no reduction in mitochondrial membrane potential, mitochondria were extensively fragmented, and mitochondrial ultrastructure was grossly aberrant. In general, chronic reduction of mtPE caused more pronounced mitochondrial defects than did acute mtPE depletion. The functional and morphological changes in PSB-2 cells were largely reversed by normalization of mtPE content by supplementation with lyso-PE, a mtPE precursor. These studies demonstrate that even a modest reduction of mtPE in mammalian cells profoundly alters mitochondrial functions.
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Affiliation(s)
- Guergana Tasseva
- Group on the Molecular and Cell Biology of Lipids, University of Alberta, Edmonton, Alberta T6G 2S2, Canada
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25
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Cumero S, Fogolari F, Domenis R, Zucchi R, Mavelli I, Contessi S. Mitochondrial F(0) F(1) -ATP synthase is a molecular target of 3-iodothyronamine, an endogenous metabolite of thyroid hormone. Br J Pharmacol 2012; 166:2331-47. [PMID: 22452346 DOI: 10.1111/j.1476-5381.2012.01958.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND AND PURPOSE 3-iodothyronamine (T1AM) is a metabolite of thyroid hormone acting as a signalling molecule via non-genomic effectors and can reach intracellular targets. Because of the importance of mitochondrial F(0) F(1) -ATP synthase as a drug target, here we evaluated interactions of T1AM with this enzyme. EXPERIMENTAL APPROACH Kinetic analyses were performed on F(0) F(1) -ATP synthase in sub-mitochondrial particles and soluble F(1) -ATPase. Activity assays and immunodetection of the inhibitor protein IF(1) were used and combined with molecular docking analyses. Effects of T1AM on H9c2 cardiomyocytes were measured by in situ respirometric analysis. KEY RESULTS T1AM was a non-competitive inhibitor of F(0) F(1) -ATP synthase whose binding was mutually exclusive with that of the inhibitors IF(1) and aurovertin B. Both kinetic and docking analyses were consistent with two different binding sites for T1AM. At low nanomolar concentrations, T1AM bound to a high-affinity region most likely located within the IF(1) binding site, causing IF(1) release. At higher concentrations, T1AM bound to a low affinity-region probably located within the aurovertin binding cavity and inhibited enzyme activity. Low nanomolar concentrations of T1AM increased ADP-stimulated mitochondrial respiration in cardiomyocytes, indicating activation of F(0) F(1) -ATP synthase consistent with displacement of endogenous IF(1,) , reinforcing the in vitro results. CONCLUSIONS AND IMPLICATIONS Effects of T1AM on F(0) F(1) -ATP synthase were twofold: IF(1) displacement and enzyme inhibition. By targeting F(0) F(1) -ATP synthase within mitochondria, T1AM might affect cell bioenergetics with a positive effect on mitochondrial energy production at low, endogenous, concentrations. T1AM putative binding locations overlapping with IF(1) and aurovertin binding sites are described.
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Affiliation(s)
- S Cumero
- Department of Medical and Biological Sciences, MATI Centre of Excellence, University of Udine, Udine, Italy
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26
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Fujikawa M, Imamura H, Nakamura J, Yoshida M. Assessing actual contribution of IF1, inhibitor of mitochondrial FoF1, to ATP homeostasis, cell growth, mitochondrial morphology, and cell viability. J Biol Chem 2012; 287:18781-7. [PMID: 22493494 DOI: 10.1074/jbc.m112.345793] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
F(o)F(1)-ATP synthase (F(o)F(1)) synthesizes ATP in mitochondria coupled with proton flow driven by the proton motive force (pmf) across membranes. It has been known that isolated IF1, an evolutionarily well conserved mitochondrial protein, can inhibit the ATP hydrolysis activity of F(o)F(1). Here, we generated HeLa cells with permanent IF1 knockdown (IF1-KD cells) and compared their energy metabolism with control cells. Under optimum growth conditions, IF1-KD cells have lower cellular ATP levels and generate a higher pmf and more reactive oxygen species. Nonetheless, IF1-KD cells and control cells show the same rates of cell growth, glucose consumption, and mitochondrial ATP synthesis. Furthermore, contrary to previous reports, the morphology of mitochondria in IF1-KD cells appears to be normal. When cells encounter sudden dissipation of pmf, the cytoplasmic ATP level in IF1-KD cells drops immediately (~1 min), whereas it remains unchanged in the control cells, indicating occurrence of futile ATP hydrolysis by F(o)F(1) in the absence of IF1. The lowered ATP level in IF1-KD cells then recovers gradually (~10 min) to the original level by consuming more glucose than control cells. The viability of IF1-KD cells and control cells is the same in the absence of pmf. Thus, IF1 contributes to ATP homeostasis, but its deficiency does not affect the growth and survival of HeLa cells. Only when cells are exposed to chemical ischemia (no glycolysis and no respiration) or high concentrations of reactive oxygen species does IF1 exhibit its ability to alleviate cell injury.
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Affiliation(s)
- Makoto Fujikawa
- International Cooperative Research Project (ICORP), ATP Synthesis Regulation Project, Japan Science and Technology Agency, Tokyo, Japan
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27
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Domenis R, Bisetto E, Rossi D, Comelli M, Mavelli I. Glucose-modulated mitochondria adaptation in tumor cells: a focus on ATP synthase and inhibitor Factor 1. Int J Mol Sci 2012; 13:1933-1950. [PMID: 22408432 PMCID: PMC3292001 DOI: 10.3390/ijms13021933] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 01/06/2012] [Accepted: 01/30/2012] [Indexed: 11/16/2022] Open
Abstract
Warburg's hypothesis has been challenged by a number of studies showing that oxidative phosphorylation is repressed in some tumors, rather than being inactive per se. Thus, treatments able to shift energy metabolism by activating mitochondrial pathways have been suggested as an intriguing basis for the optimization of antitumor strategies. In this study, HepG2 hepatocarcinoma cells were cultivated with different metabolic substrates under conditions mimicking "positive" (activation/biogenesis) or "negative" (silencing) mitochondrial adaptation. In addition to the expected up-regulation of mitochondrial biogenesis, glucose deprivation caused an increase in phosphorylating respiration and a rise in the expression levels of the ATP synthase β subunit and Inhibitor Factor 1 (IF1). Hyperglycemia, on the other hand, led to a markedly decreased level of the transcriptional coactivator PGC-α suggesting down-regulation of mitochondrial biogenesis, although no change in mitochondrial mass and no impairment of phosphorylating respiration were observed. Moreover, a reduction in mitochondrial networking and in ATP synthase dimer stability was produced. No effect on β-ATP synthase expression was elicited. Notably, hyperglycemia caused an increase in IF1 expression levels, but it did not alter the amount of IF1 associated with ATP synthase. These results point to a new role of IF1 in relation to high glucose utilization by tumor cells, in addition to its well known effect upon mitochondrial ATP synthase regulation.
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Affiliation(s)
- Rossana Domenis
- Department of Medical and Biological Sciences, University of Udine, p.le Kolbe 4, 33100 Udine, Italy; E-Mails: (R.D.); (E.B.); (D.R.); (M.C.)
- M.A.T.I. Centre of Excellence, University of Udine, p.le Kolbe 4, 33100 Udine, Italy
| | - Elena Bisetto
- Department of Medical and Biological Sciences, University of Udine, p.le Kolbe 4, 33100 Udine, Italy; E-Mails: (R.D.); (E.B.); (D.R.); (M.C.)
- M.A.T.I. Centre of Excellence, University of Udine, p.le Kolbe 4, 33100 Udine, Italy
| | - Davide Rossi
- Department of Medical and Biological Sciences, University of Udine, p.le Kolbe 4, 33100 Udine, Italy; E-Mails: (R.D.); (E.B.); (D.R.); (M.C.)
- M.A.T.I. Centre of Excellence, University of Udine, p.le Kolbe 4, 33100 Udine, Italy
| | - Marina Comelli
- Department of Medical and Biological Sciences, University of Udine, p.le Kolbe 4, 33100 Udine, Italy; E-Mails: (R.D.); (E.B.); (D.R.); (M.C.)
- M.A.T.I. Centre of Excellence, University of Udine, p.le Kolbe 4, 33100 Udine, Italy
| | - Irene Mavelli
- Department of Medical and Biological Sciences, University of Udine, p.le Kolbe 4, 33100 Udine, Italy; E-Mails: (R.D.); (E.B.); (D.R.); (M.C.)
- M.A.T.I. Centre of Excellence, University of Udine, p.le Kolbe 4, 33100 Udine, Italy
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28
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ATP synthase superassemblies in animals and plants: Two or more are better. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:1185-97. [PMID: 21679683 DOI: 10.1016/j.bbabio.2011.05.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 05/30/2011] [Accepted: 05/31/2011] [Indexed: 12/11/2022]
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29
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Comelli M, Domenis R, Bisetto E, Contin M, Marchini M, Ortolani F, Tomasetig L, Mavelli I. Cardiac differentiation promotes mitochondria development and ameliorates oxidative capacity in H9c2 cardiomyoblasts. Mitochondrion 2011; 11:315-26. [DOI: 10.1016/j.mito.2010.12.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 10/20/2010] [Accepted: 12/03/2010] [Indexed: 12/14/2022]
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30
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Giorgio V, Bisetto E, Soriano ME, Dabbeni-Sala F, Basso E, Petronilli V, Forte MA, Bernardi P, Lippe G. Cyclophilin D modulates mitochondrial F0F1-ATP synthase by interacting with the lateral stalk of the complex. J Biol Chem 2009; 284:33982-8. [PMID: 19801635 PMCID: PMC2797168 DOI: 10.1074/jbc.m109.020115] [Citation(s) in RCA: 235] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 09/02/2009] [Indexed: 01/02/2023] Open
Abstract
Blue native gel electrophoresis purification and immunoprecipitation of F(0)F(1)-ATP synthase from bovine heart mitochondria revealed that cyclophilin (CyP) D associates to the complex. Treatment of intact mitochondria with the membrane-permeable bifunctional reagent dimethyl 3,3-dithiobis-propionimidate (DTBP) cross-linked CyPD with the lateral stalk of ATP synthase, whereas no interactions with F(1) sector subunits, the ATP synthase natural inhibitor protein IF1, and the ATP/ADP carrier were observed. The ATP synthase-CyPD interactions have functional consequences on enzyme catalysis and are modulated by phosphate (increased CyPD binding and decreased enzyme activity) and cyclosporin (Cs) A (decreased CyPD binding and increased enzyme activity). Treatment of MgATP submitochondrial particles or intact mitochondria with CsA displaced CyPD from membranes and activated both hydrolysis and synthesis of ATP sustained by the enzyme. No effect of CsA was detected in CyPD-null mitochondria, which displayed a higher specific activity of the ATP synthase than wild-type mitochondria. Modulation by CyPD binding appears to be independent of IF1, whose association to ATP synthase was not affected by CsA treatment. These findings demonstrate that CyPD association to the lateral stalk of ATP synthase modulates the activity of the complex.
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Affiliation(s)
- Valentina Giorgio
- From the Department of Biomedical Sciences and the Consiglio Nazionale delle Ricerche Institute of Neuroscience and
| | - Elena Bisetto
- the Department of Biomedical Sciences, University of Udine, I-33100 Udine, Italy, and
| | - Maria Eugenia Soriano
- From the Department of Biomedical Sciences and the Consiglio Nazionale delle Ricerche Institute of Neuroscience and
| | - Federica Dabbeni-Sala
- the Department of Pharmacology and Anesthesiology, University of Padova, I-35121 Padova, Italy
| | - Emy Basso
- From the Department of Biomedical Sciences and the Consiglio Nazionale delle Ricerche Institute of Neuroscience and
| | - Valeria Petronilli
- From the Department of Biomedical Sciences and the Consiglio Nazionale delle Ricerche Institute of Neuroscience and
| | - Michael A. Forte
- the Vollum Institute, Oregon Health and Sciences University, Portland, Oregon 97239
| | - Paolo Bernardi
- From the Department of Biomedical Sciences and the Consiglio Nazionale delle Ricerche Institute of Neuroscience and
| | - Giovanna Lippe
- the Department of Biomedical Sciences, University of Udine, I-33100 Udine, Italy, and
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31
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Campanella M, Parker N, Tan CH, Hall AM, Duchen MR. IF(1): setting the pace of the F(1)F(o)-ATP synthase. Trends Biochem Sci 2009; 34:343-50. [PMID: 19559621 DOI: 10.1016/j.tibs.2009.03.006] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2009] [Revised: 03/26/2009] [Accepted: 03/26/2009] [Indexed: 12/15/2022]
Abstract
When mitochondrial function is compromised and the mitochondrial membrane potential (Deltapsi(m)) falls below a threshold, the F(1)F(o)-ATP synthase can reverse, hydrolysing ATP to pump protons out of the mitochondrial matrix. Although this activity can deplete ATP and precipitate cell death, it is limited by the mitochondrial protein IF(1), an endogenous F(1)F(o)-ATPase inhibitor. IF(1), therefore, preserves ATP at the expense of Deltapsi(m). Despite a wealth of detailed knowledge on the biochemistry of the interaction of IF(1) and the F(1)F(o)-ATPase, little is known about its physiological activity. Emerging research suggests that IF(1) has a wider ranging impact on mitochondrial structure and function than previously thought.
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32
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Lippe G, Bisetto E, Comelli M, Contessi S, Di Pancrazio F, Mavelli I. Mitochondrial and cell-surface F0F1ATPsynthase in innate and acquired cardioprotection. J Bioenerg Biomembr 2009; 41:151-7. [PMID: 19387805 DOI: 10.1007/s10863-009-9208-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mitochondria are central to heart function and dysfunction, and the pathways activated by different cardioprotective interventions mostly converge on mitochondria. In a context of perspectives in innate and acquired cardioprotection, we review some recent advances in F(0)F(1)ATPsynthase structure/function and regulation in cardiac cells. We focus on three topics regarding the mitochondrial F(0)F(1)ATPsynthase and the plasma membrane enzyme, i.e.: i) the crucial role of cardiac mitochondrial F(0)F(1)ATPsynthase regulation by the inhibitory protein IF(1) in heart preconditioning strategies; ii) the structure and function of mitochondrial F(0)F(1)ATPsynthase oligomers in mammalian myocardium as possible endogenous factors of mitochondria resistance to ischemic insult; iii) the external location and characterization of plasma membrane F(0)F(1) ATP synthase in search for possible actors of its regulation, such as IF(1) and calmodulin, at cell surface.
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Affiliation(s)
- Giovanna Lippe
- Department of Biomedical Sciences and Technologies and M.A.T.I. Centre of Excellence, University of Udine, P.le Kolbe 4, 33100, Udine, Italy
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33
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Bisetto E, Picotti P, Giorgio V, Alverdi V, Mavelli I, Lippe G. Functional and stoichiometric analysis of subunit e in bovine heart mitochondrial F(0)F(1)ATP synthase. J Bioenerg Biomembr 2008; 40:257-67. [PMID: 18958608 DOI: 10.1007/s10863-008-9183-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Accepted: 09/16/2008] [Indexed: 12/21/2022]
Abstract
The role of the integral inner membrane subunit e in self-association of F(0)F(1)ATP synthase from bovine heart mitochondria was analyzed by in situ limited proteolysis, blue native PAGE/iterative SDS-PAGE, and LC-MS/MS. Selective degradation of subunit e, without disrupting membrane integrity or ATPase capacity, altered the oligomeric distribution of F(0)F(1)ATP synthase, by eliminating oligomers and reducing dimers in favor of monomers. The stoichiometry of subunit e was determined by a quantitative MS-based proteomics approach, using synthetic isotope-labelled reference peptides IAQL*EEVK, VYGVGSL*ALYEK, and ELAEAQEDTIL*K to quantify the b, gamma and e subunits, respectively. Accuracy of the method was demonstrated by confirming the 1:1 stoichiometry of subunits gamma and b. Altogether, the results indicate that the integrity of a unique copy of subunit e is essential for self-association of mammalian F(0)F(1)ATP synthase.
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Affiliation(s)
- Elena Bisetto
- Department of Biomedical Sciences and Technologies and M.A.T.I. Centre of Excellence, University of Udine, Udine, Italy
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34
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García-Trejo JJ, Morales-Ríos E. Regulation of the F1F0-ATP synthase rotary nanomotor in its monomeric-bacterial and dimeric-mitochondrial forms. J Biol Phys 2008; 34:197-212. [PMID: 19669503 DOI: 10.1007/s10867-008-9114-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Accepted: 09/08/2008] [Indexed: 12/21/2022] Open
Abstract
The F(1)F(0)-adenosine triphosphate (ATP) synthase rotational motor synthesizes most of the ATP required for living from adenosine diphosphate, Pi, and a proton electrochemical gradient across energy-transducing membranes of bacteria, chloroplasts, and mitochondria. However, as a reversible nanomotor, it also hydrolyzes ATP during de-energized conditions in all energy-transducing systems. Thus, different subunits and mechanisms have emerged in nature to control the intrinsic rotation of the enzyme to favor the ATP synthase activity over its opposite and commonly wasteful ATPase turnover. Recent advances in the structural analysis of the bacterial and mitochondrial ATP synthases are summarized to review the distribution and mechanism of the subunits that are part of the central rotor and regulate its gyration. In eubacteria, the epsilon subunit works as a ratchet to favor the rotation of the central stalk in the ATP synthase direction by extending and contracting two alpha-helixes of its C-terminal side and also by binding ATP with low affinity in thermophilic bacteria. On the other hand, in bovine heart mitochondria, the so-called inhibitor protein (IF(1)) interferes with the intrinsic rotational mechanism of the central gamma subunit and with the opening and closing of the catalytic beta-subunits to inhibit its ATPase activity. Besides its inhibitory role, the IF(1) protein also promotes the dimerization of the bovine and rat mitochondrial enzymes, albeit it is not essential for dimerization of the yeast F(1)F(0) mitochondrial complex. High-resolution electron microscopy of the dimeric enzyme in its bovine and yeast forms shows a conical shape that is compatible with the role of the ATP synthase dimer in the formation of tubular the cristae membrane of mitochondria after further oligomerization. Dimerization of the mitochondrial ATP synthase diminishes the rotational drag of the central rotor that would decrease the coupling efficiency between rotation of the central stalk and ATP synthesis taking place at the F(1) portion. In addition, F(1)F(0) dimerization and its further oligomerization also increase the stability of the enzyme to natural or experimentally induced destabilizing conditions.
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Affiliation(s)
- José J García-Trejo
- Facultad de Química, Departamento de Biología, Lab. F-117, Universidad Nacional Autónoma de México, México, D.F., 04510, México.
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Campanella M, Casswell E, Chong S, Farah Z, Wieckowski MR, Abramov AY, Tinker A, Duchen MR. Regulation of mitochondrial structure and function by the F1Fo-ATPase inhibitor protein, IF1. Cell Metab 2008; 8:13-25. [PMID: 18590689 DOI: 10.1016/j.cmet.2008.06.001] [Citation(s) in RCA: 208] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Revised: 04/16/2008] [Accepted: 06/02/2008] [Indexed: 11/18/2022]
Abstract
When mitochondrial respiration is compromised, the F(1)F(o)-ATP synthase reverses and consumes ATP, serving to maintain the mitochondrial membrane potential (Delta psi(m)). This process is mitigated by IF(1). As little is known of the cell biology of IF(1), we have investigated the functional consequences of varying IF(1) expression. We report that, (1) during inhibition of respiration, IF(1) conserves ATP at the expense of Delta psi(m); (2) overexpression of IF(1) is protective against ischemic injury; (3) relative IF(1) expression level varies between tissues and cell types and dictates the response to inhibition of mitochondrial respiration; (4) the density of mitochondrial cristae is increased by IF(1) overexpression and decreased by IF(1) suppression; and (5) IF(1) overexpression increases the formation of dimeric ATP synthase complexes and increases F(1)F(o)-ATP synthase activity. Thus, IF(1) regulates mitochondrial function and structure under both physiological and pathological conditions.
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Vonck J, Schäfer E. Supramolecular organization of protein complexes in the mitochondrial inner membrane. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1793:117-24. [PMID: 18573282 DOI: 10.1016/j.bbamcr.2008.05.019] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Revised: 05/21/2008] [Accepted: 05/23/2008] [Indexed: 12/29/2022]
Abstract
The liquid state model that envisions respiratory chain complexes diffusing freely in the membrane is increasingly challenged by reports of supramolecular organization of the complexes in the mitochondrial inner membrane. Supercomplexes of complex III with complex I and/or IV can be isolated after solubilisation with mild detergents like digitonin. Electron microscopic studies have shown that these have a distinct architecture and are not random aggregates. A 3D reconstruction of a I1III2IV1 supercomplex shows that the ubiquinone and cytochrome c binding sites of the individual complexes are facing each other, suggesting a role in substrate channelling. Formation of supercomplexes plays a role in the assembly and stability of the complexes, suggesting that the supercomplexes are the functional state of the respiratory chain. Furthermore, a supramolecular organisation of ATP synthases has been observed in mitochondria, where ATP synthase is organised in dimer rows. Dimers can be isolated by mild detergent extraction and recent electron microscopic studies have shown that the membrane domains of the two partners in the dimer are at an angle to each other, indicating that in vivo the dimers would cause the membrane to bend. The suggested role in crista formation is supported by the observation of rows of ATP synthase dimers in the most curved parts of the cristae. Together these observations show that the mitochondrial inner membrane is highly organised and that the molecular events leading to ATP synthesis are carefully coordinated.
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Affiliation(s)
- Janet Vonck
- Department of Structural Biology, Max-Planck-Institute of Biophysics, Max-von-Laue-Strasse 3, D-60438 Frankfurt am Main, Germany.
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Devenish RJ, Prescott M, Rodgers AJW. The structure and function of mitochondrial F1F0-ATP synthases. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 267:1-58. [PMID: 18544496 DOI: 10.1016/s1937-6448(08)00601-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We review recent advances in understanding of the structure of the F(1)F(0)-ATP synthase of the mitochondrial inner membrane (mtATPase). A significant achievement has been the determination of the structure of the principal peripheral or stator stalk components bringing us closer to achieving the Holy Grail of a complete 3D structure for the complex. A major focus of the field in recent years has been to understand the physiological significance of dimers or other oligomer forms of mtATPase recoverable from membranes and their relationship to the structure of the cristae of the inner mitochondrial membrane. In addition, the association of mtATPase with other membrane proteins has been described and suggests that further levels of functional organization need to be considered. Many reports in recent years have concerned the location and function of ATP synthase complexes or its component subunits on the external surface of the plasma membrane. We consider whether the evidence supports complete complexes being located on the cell surface, the biogenesis of such complexes, and aspects of function especially related to the structure of mtATPase.
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Affiliation(s)
- Rodney J Devenish
- Department of Biochemistry and Molecular Biology, and ARC Centre of Excellence in Microbial Structural and Functional Genomics, Monash University, Clayton Campus, Victoria, 3800, Australia
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Bisetto E, Di Pancrazio F, Simula MP, Mavelli I, Lippe G. Mammalian ATPsynthase monomerversus dimer profiled by blue native PAGE and activity stain. Electrophoresis 2007; 28:3178-85. [PMID: 17703470 DOI: 10.1002/elps.200700066] [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: 12/22/2022]
Abstract
Studies into the effects of oligomerization on F(0)F(1)ATPsynthase function are contradictory. We optimized the in-gel ATPase assay to investigate the functional differences of monomers versus dimers. In Triton X-100 extracts of heavy bovine heart mitochondria (HBHM) and mitoplasts, but not submitochondrial particles (MgATP-SMP), dimers had greater specific activity than monomers: at 30 degrees C, the dimer/monomer activity ratios were 2.3, 1.4, and 1.0, respectively. These differences in HBHM and mitoplasts extracts were enhanced at 37 degrees C but lost at 20 degrees C. In mitoplasts but not in MgATP-SMP, dimers were selectively shielded from limited chymotrypsin degradation of F(1) alpha subunit, possibly due to interactions with other proteins or ligands in the native inner membrane. Despite these differences, all three preparations had similar percentages of dimers and similar contents of the native inhibitor IF(1) in Vm (monomer) and (dimer) Vd. These results suggest that, in native membrane, monomers and dimers are functionally distinct.
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Affiliation(s)
- Elena Bisetto
- Department of Biomedical Sciences and Technologies, University of Udine, Udine, Italy
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Belogrudov GI, Schirf V, Demeler B. Reversible self-association of recombinant bovine factor B. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2006; 1764:1741-9. [PMID: 17049939 PMCID: PMC1802098 DOI: 10.1016/j.bbapap.2006.09.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 09/06/2006] [Accepted: 09/07/2006] [Indexed: 11/17/2022]
Abstract
The recombinant bovine factor B, obtained by a newly developed bacterial expression system, was found to exhibit features characteristic of a reversible self-associating system. Using size-sieving chromatography, distribution of the factor B species ranged from a monomer to a trimer, but not oligomers of higher molecular weights. At high protein concentrations, factor B migrated as a single band in a native gel. Cross-linking with the amino-reactive cross-linking reagent bis (sulfosuccinimidyl) suberate (BS), at a low cross-linker to protein ratio yielded cross-linked products identified as factor B dimer and trimer. The cross-linking pattern was shown to be a function of the protein and cross-linker concentrations. The range of sedimentation coefficients in a sedimentation velocity experiment suggested that the largest particle present in the distribution was more than twice as large as the smallest. The data obtained under multiple conditions in the sedimentation equilibrium experiments are best fit to a model describing a reversible self-association of a monomer-trimer of factor B species, with a dissociation constant Kd(1,3)=2.48x10(-10) M(2).
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Affiliation(s)
- Grigory I Belogrudov
- Department of Physiology, David Geffen School of Medicine, University of California at Los Angeles, and VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA.
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Dunnick J, Blackshear P, Kissling G, Cunningham M, Parker J, Nyska A. Critical pathways in heart function: bis(2-chloroethoxy)methane-induced heart gene transcript change in F344 rats. Toxicol Pathol 2006; 34:348-56. [PMID: 16844662 DOI: 10.1080/01926230600798583] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Gene transcript changes after exposure to the heart toxin, bis(2-chloroethoxy)methane (CEM), were analyzed to elucidate mechanisms in cardiotoxicity and recovery. CEM was administered to 5-week-old male F344/N rats at 0, 200, 400, or 600 mg/kg by dermal exposure, 5 days per week, for a total of 12 doses by study day 16. Heart toxicity occurred after 2 days of dosing in all 3 regions of the heart (atrium, ventricle, interventricular septum) and was characterized by myofiber vacuolation, necrosis, mononuclear-cell infiltration, and atrial thrombosis. Ultrastructural analysis revealed that the primary site of damage was the mitochondrion. By day 5, even though dosing was continued, the toxic lesions in the heart began to resolve, and by study day 16, the heart appeared histologically normal. RNA was extracted from whole hearts after 2 or 5 days of CEM dosing. After a screen for transcript change by microarray analysis, dose-response trends for selected transcripts were analyzed by qRT-PCR. The selected transcripts code for proteins involved in energy production, control of calcium levels, and maintenance of heart function. The down-regulation of ATP subunit transcripts (Atp5j, ATP5k), which reside in the mitochondrial membranes, indicated a decrease in energy supply at day 2 and day 5. This was accompanied by down-regulation of transcripts involved in high-energy consumption processes such as membrane transport and ion channel transcripts (e.g., abc1a, kcnj12). The up-regulation of transcripts encoding for temperature regulation and calcium binding proteins (ucp1 and calb3) only at the 2 low exposure levels, suggest that these adaptive processes cannot occur in association with severe cardiotoxicity as seen in hearts at the high exposure level. Transcript expression changes occurred within 2 days of CEM exposure, and were dose-and time-dependent. The heart transcript changes suggest that CEM cardiotoxicity activates protective processes associated energy conservation and maintenance of heart function.
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Affiliation(s)
- J Dunnick
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
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41
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Wittig I, Carrozzo R, Santorelli FM, Schägger H. Supercomplexes and subcomplexes of mitochondrial oxidative phosphorylation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1757:1066-72. [PMID: 16782043 DOI: 10.1016/j.bbabio.2006.05.006] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 04/07/2006] [Accepted: 05/03/2006] [Indexed: 10/24/2022]
Abstract
Dimerization or oligomerization of ATP synthase has been proposed to play an important role for mitochondrial cristae formation and to be involved in regulating ATP synthase activity. We found comparable oligomycin-sensitive ATPase activity for monomeric and oligomeric ATP synthase suggesting that oligomerization/monomerization dynamics are not directly involved in regulating ATP synthase activity. Binding of the natural IF1 inhibitor protein has been shown to induce dimerization of F1-subcomplexes. This suggested that binding of IF1 might also dimerize holo ATP synthase, and possibly link dimerization and inhibition. Analyzing mitochondria of human rho zero cells that contain mitochondria but lack mitochondrial DNA, we identified three subcomplexes of ATP synthase: (i) F1 catalytic domain, (ii) F1-domain with bound IF1, and (iii) F1-c subcomplex with bound IF1 and a ring of subunits c. Since both IF1 containing subcomplexes were present in monomeric state and exhibited considerably reduced ATPase activity as compared to the third subcomplex lacking IF1, we postulate that inhibition and induction of dimerization of F1-subcomplexes by IF1 are independent events. F1-subcomplexes were also found in mitochondria of patients with specific mitochondrial disorders, and turned out to be useful for the clinical differentiation between various types of mitochondrial biosynthesis disorders. Supramolecular associations of respiratory complexes, the "respirasomes", seem not to be the largest assemblies in the structural organization of the respiratory chain, as suggested by differential solubilization of mitochondria and electron microscopic analyses of whole mitochondria. We present a model for a higher supramolecular association of respirasomes into a "respiratory string".
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Affiliation(s)
- Ilka Wittig
- Molekulare Bioenergetik, Zentrum der Biologischen Chemie, Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7, Haus 26, D-60590 Frankfurt, Germany.
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Krause F. Detection and analysis of protein–protein interactions in organellar and prokaryotic proteomes by native gel electrophoresis: (Membrane) protein complexes and supercomplexes. Electrophoresis 2006; 27:2759-81. [PMID: 16817166 DOI: 10.1002/elps.200600049] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
It is an essential and challenging task to unravel protein-protein interactions in their actual in vivo context. Native gel systems provide a separation platform allowing the analysis of protein complexes on a rather proteome-wide scale in a single experiment. This review focus on blue-native (BN)-PAGE as the most versatile and successful gel-based approach to separate soluble and membrane protein complexes of intricate protein mixtures derived from all biological sources. BN-PAGE is a charge-shift method with a running pH of 7.5 relying on the gentle binding of anionic CBB dye to all membrane and many soluble protein complexes, leading to separation of protein species essentially according to their size and superior resolution than other fractionation techniques can offer. The closely related colorless-native (CN)-PAGE, whose applicability is restricted to protein species with intrinsic negative net charge, proved to provide an especially mild separation capable of preserving weak protein-protein interactions better than BN-PAGE. The essential conditions determining the success of detecting protein-protein interactions are the sample preparations, e.g. the efficiency/mildness of the detergent solubilization of membrane protein complexes. A broad overview about the achievements of BN- and CN-PAGE studies to elucidate protein-protein interactions in organelles and prokaryotes is presented, e.g. the mitochondrial protein import machinery and oxidative phosphorylation supercomplexes. In many cases, solubilization with digitonin was demonstrated to facilitate an efficient and particularly gentle extraction of membrane protein complexes prone to dissociation by treatment with other detergents. In general, analyses of protein interactomes should be carried out by both BN- and CN-PAGE.
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Affiliation(s)
- Frank Krause
- Department of Chemistry, Physical Biochemistry, Darmstadt University of Technology, Germany.
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Di Pancrazio F, Bisetto E, Alverdi V, Mavelli I, Esposito G, Lippe G. Differential steady-state tyrosine phosphorylation of two oligomeric forms of mitochondrial F0F1ATPsynthase: a structural proteomic analysis. Proteomics 2006; 6:921-6. [PMID: 16400683 DOI: 10.1002/pmic.200500077] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We investigated tyrosine phosphorylation of F(0)F(1)ATPsynthase using 3-D blue native (BN)-SDS-PAGE, a refinement of the electrophoretic analysis of mitochondrial complexes. Bovine heart mitochondria were detergent-solubilized and subjected to BN-PAGE. Bands of ATPsynthase monomer (Vmon) and dimer (Vdim) were excised and submitted to SDS-PAGE and immunoblotting. One protein corresponding to F(1)gamma subunit was detected by anti-phosphotyrosine antibody in monomer but not in dimer. This was confirmed by MS peptide mapping. LC-ESI/MS analysis after 3-D SDS-PAGE demonstrated phosphotyrosine in fragment 43-54. NetPhos scores predicted the phosphorylated residue to be Tyr52, in a solvent-accessible loop at the foot of the F(1) central stalk.
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Affiliation(s)
- Francesca Di Pancrazio
- Department of Biomedical Sciences and Technologies, University of Udine, MATI Center of Excellence, Udine, Italy
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Abstract
Clear-native PAGE (CN-PAGE) separates acidic water-soluble and membrane proteins (pI < 7) in an acrylamide gradient gel, and usually has lower resolution than blue-native PAGE (BN-PAGE). The migration distance depends on the protein intrinsic charge, and on the pore size of the gradient gel. This complicates estimation of native masses and oligomerization states when compared to BN-PAGE, which uses negatively charged protein-bound Coomassie-dye to impose a charge shift on the proteins. Therefore, BN-PAGE rather than CN-PAGE is commonly used for standard analyses. However, CN-PAGE offers advantages whenever Coomassie-dye interferes with techniques required to further analyze the native complexes, e.g., determination of catalytic activities, as shown here for mitochondrial ATP synthase, or efficient microscale separation of membrane protein complexes for fluorescence resonance energy transfer (FRET) analyses. CN-PAGE is milder than BN-PAGE. Especially the combination of digitonin and CN-PAGE can retain labile supramolecular assemblies of membrane protein complexes that are dissociated under the conditions of BN-PAGE. Enzymatically active oligomeric states of mitochondrial ATP synthase previously not detected using BN-PAGE were identified by CN-PAGE.
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Affiliation(s)
- Ilka Wittig
- Zentrum der Biologischen Chemie, Fachbereich Medizin, Universität Frankfurt, Germany
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Minauro-Sanmiguel F, Wilkens S, García JJ. Structure of dimeric mitochondrial ATP synthase: novel F0 bridging features and the structural basis of mitochondrial cristae biogenesis. Proc Natl Acad Sci U S A 2005; 102:12356-8. [PMID: 16105947 PMCID: PMC1194923 DOI: 10.1073/pnas.0503893102] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Indexed: 11/18/2022] Open
Abstract
The F1F0-ATP synthase exists as a dimer in mitochondria, where it is essential for the biogenesis of the inner membrane cristae. How two ATP synthase complexes dimerize to promote cristae formation is unknown. Here we resolved the structure of the dimeric F1F0 ATP synthase complex isolated from bovine heart mitochondria by transmission electron microscopy. The structure of the ATP synthase dimer has an overall conic appearance that is consistent with the proposed role of the dimeric enzyme in mitochondrial cristae biogenesis. The ATP synthase dimer interface is formed by contacts on both the F0 and F1 domains. A cross-bridging protein density was resolved which connects the two F0 domains on the intermembrane space side of the membrane. On the matrix side of the complex, the two F1 moieties are connected by a protein bridge, which is attributable to the IF1 inhibitor protein.
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Affiliation(s)
- Fernando Minauro-Sanmiguel
- Departamento de Bioquímica, Instituto Nacional de Cardiología Ignacio Chávez, Tlalpan 14080 Mexico D.F., México
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Krause F, Reifschneider NH, Goto S, Dencher NA. Active oligomeric ATP synthases in mammalian mitochondria. Biochem Biophys Res Commun 2005; 329:583-90. [PMID: 15737625 DOI: 10.1016/j.bbrc.2005.02.010] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2005] [Indexed: 11/22/2022]
Abstract
Recently, by analysis of mildly solubilized mitochondrial membranes new biochemical evidences were obtained for the occurrence of ATP synthase dimers in mitochondria of different eukaryotes from yeast to mammals. In the case of yeast even higher ATP synthase oligomers could be found. Here, we analysed by BN- and CN-PAGE mammalian (bovine and rat) mitochondria from five different tissues, which were efficiently but very mildly solubilized with digitonin. In mitochondria from all investigated tissues besides ATP synthase monomers (V(1)) not only dimeric ATP synthase (V(2)) but for the first time also higher oligomers, at least trimers (V(3)) and tetramers (V(4)), were separated. Compared with BN-PAGE, by CN-PAGE analysis the yields of preserved respiratory supercomplexes as well as of oligomeric ATP synthases (V(2-4)) were significantly increased. The latter represent the majority of total ATP synthases in all cases. Importantly, all different ATP synthase species from the five tissues displayed in-gel ATP hydrolase activity, suggesting that homooligomeric ATP synthases are the constitutive, enzymatically competent organization of mammalian ATP synthases in the inner mitochondrial membrane.
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Affiliation(s)
- Frank Krause
- Physical Biochemistry, Department of Chemistry, Darmstadt University of Technology, Petersenstrasse 22, D-64287 Darmstadt, Germany.
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Domínguez-Ramírez L, Garza-Ramos G, Najera H, Mendoza-Hernández G, Gómez-Puyou A, de Gómez-Puyou MT. Interconversion between dimers and monomers of endogenous mitochondrial F1-inhibitor protein complexes and the release of the inhibitor protein. Spectroscopic characteristics of the complexes. J Bioenerg Biomembr 2004; 36:503-13. [PMID: 15692729 DOI: 10.1007/s10863-004-8997-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The F1-inhibitor protein complex (F1-IP) was purified from heart submitochondrial particles. Size exclusion chromatography of the endogenous complex showed that it contains dimers (D) and monomers (M) of F1-IP. Further chromatographic analysis showed that D and M interconvert. At high protein concentrations, the interconversion reaction is shifted toward the D species. The release of the inhibiting action of IP is faster at low than at high protein concentrations. During activation of F1, the M species accumulates through a process that is faster than the release of IP from F1. These findings indicate that the activation of F1-IP involves the transformation of D into M, which subsequently loses IP. The spectroscopic characteristics of D, M, and free F1 show that the binding of IP and dimerization modifies the fluorescence intensity of tyrosine residues and that of the single tryptophan of F1 which is far from the IP binding site.
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Rexroth S, Meyer Zu Tittingdorf JMW, Schwassmann HJ, Krause F, Seelert H, Dencher NA. Dimeric H+-ATP synthase in the chloroplast of Chlamydomonas reinhardtii. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2004; 1658:202-11. [PMID: 15450958 DOI: 10.1016/j.bbabio.2004.05.014] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Revised: 05/28/2004] [Accepted: 05/28/2004] [Indexed: 11/18/2022]
Abstract
H+-ATP synthase is the dominant ATP production site in mitochondria and chloroplasts. So far, dimerization of ATP synthase has been observed only in mitochondria by biochemical and electron microscopic investigations. Although the physiological relevance remains still enigmatic, dimerization was proposed to be a unique feature of the mitochondrion [Biochim. Biophys. Acta 1555 (2002) 154]. It is hard to imagine, however, that closely related protein complexes of mitochondria and chloroplast should show such severe differences in structural organization. We present the first evidences for dimerization of chloroplast ATP synthases within the thylakoid membrane. By investigation of the thylakoid membrane of Chlamydomonas reinhardtii by blue-native polyacrylamide gel electrophoresis, dimerization of the chloroplast ATP synthase was detected. Chloroplast ATP synthase dimer dissociates into monomers upon incubation with vanadate or phosphate but not by incubation with molybdate, while the mitochondrial dimer is not affected by the incubation. This suggests a distinct dimerization mechanism for mitochondrial and chloroplast ATP synthase. Since vanadate and phosphate bind to the active sites, contact sites located on the hydrophilic CF1 part are suggested for the chloroplast ATP synthase dimer. As the degree of dimerization varies with phosphate concentration, dimerization might be a response to low phosphate concentrations.
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Affiliation(s)
- Sascha Rexroth
- Physical Biochemistry, Department of Chemistry, Darmstadt University of Technology, Petersenstrasse 22, Darmstadt D-64287, Germany.
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Di Pancrazio F, Mavelli I, Isola M, Losano G, Pagliaro P, Harris DA, Lippe G. In vitro and in vivo studies of F(0)F(1)ATP synthase regulation by inhibitor protein IF(1) in goat heart. BIOCHIMICA ET BIOPHYSICA ACTA 2004; 1659:52-62. [PMID: 15511527 DOI: 10.1016/j.bbabio.2004.07.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Accepted: 07/30/2004] [Indexed: 11/28/2022]
Abstract
A method has been developed to allow the level of F(0)F(1)ATP synthase capacity and the quantity of IF(1) bound to this enzyme be measured in single biopsy samples of goat heart. ATP synthase capacity was determined from the maximal mitochondrial ATP hydrolysis rate and IF(1) content was determined by detergent extraction followed by blue native gel electrophoresis, two-dimensional SDS-PAGE and immunoblotting with anti-IF(1) antibodies. Anaesthetized open-chest goats were subjected to ischemic preconditioning and/or sudden increases of coronary blood flow (CBF) (reactive hyperemia). When hyperemia was induced before ischemic preconditioning, a steep increase in synthase capacity, followed by a deep decrease, was observed. In contrast, hyperemia did not affect synthase capacity when applied after ischemic preconditioning. Similar effects could be produced in vitro by treatment of heart biopsy samples with anoxia (down-regulation of the ATP synthase) or high-salt or high-pH buffers (up-regulation). We show that both in vitro and in vivo the same close inverse correlation exists between enzyme activity and IF(1) content, demonstrating that under all conditions tested the only significant modulator of the enzyme activity was IF(1). In addition, both in vivo and in vitro, 1.3-1.4 mol of IF(1) was predicted to fully inactivate 1 mol of synthase, thus excluding the existence of significant numbers of non-inhibitory binding sites for IF(1) in the F(0) sector.
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Affiliation(s)
- Francesca Di Pancrazio
- Department of Biomedical Sciences and Technologies and M.A.T.I. Center of Excellence, University of Udine, p.le Kolbe 4, 33100 Udine, Italy
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Zancani M, Peresson C, Biroccio A, Federici G, Urbani A, Murgia I, Soave C, Micali F, Vianello A, Macrì F. Evidence for the presence of ferritin in plant mitochondria. EUROPEAN JOURNAL OF BIOCHEMISTRY 2004; 271:3657-64. [PMID: 15355342 DOI: 10.1111/j.1432-1033.2004.04300.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, evidence for the presence of ferritins in plant mitochondria is supplied. Mitochondria were isolated from etiolated pea stems and Arabidopsis thaliana cell cultures. The proteins were separated by SDS/PAGE. A protein, with an apparent molecular mass of approximately 25-26 kDa (corresponding to that of ferritin), was cross-reacted with an antibody raised against pea seed ferritin. The mitochondrial ferritin from pea stems was also purified by immunoprecipitation. The purified protein was analyzed by MALDI-TOF mass spectrometry and the results of both mass finger print and peptide fragmentation by post source decay assign the polypeptide sequence to the pea ferritin (P < 0.05). The mitochondrial localization of ferritin was also confirmed by immunocytochemistry experiments on isolated mitochondria and cross-sections of pea stem cells. The possible role of ferritin in oxidative stress of plant mitochondria is discussed.
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Affiliation(s)
- Marco Zancani
- Dipartimento di Biologia ed Economia Agro-Industriale, Sezione di Biologia Vegetale, Università di Udine, Italy
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