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De Beer B, Villacis-Perez E, Khalighi M, Saalwaechter C, Vandenhole M, Jonckheere W, Ismaeil I, Geibel S, Van Leeuwen T, Dermauw W. QTL mapping suggests that both cytochrome P450-mediated detoxification and target-site resistance are involved in fenbutatin oxide resistance in Tetranychus urticae. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 145:103757. [PMID: 35301092 DOI: 10.1016/j.ibmb.2022.103757] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/17/2022] [Accepted: 03/05/2022] [Indexed: 06/14/2023]
Abstract
The organotin acaricide fenbutatin oxide (FBO) - an inhibitor of mitochondrial ATP-synthase - has been one of the most extensively used acaricides for the control of spider mites, and is still in use today. Resistance against FBO has evolved in many regions around the world but only few studies have investigated the molecular and genetic mechanisms of resistance to organotin acaricides. Here, we found that FBO resistance is polygenic in two genetically distant, highly resistant strains of the spider mite Tetranychus urticae, MAR-AB and MR-VL. To identify the loci underlying FBO resistance, two independent bulked segregant analysis (BSA) based QTL mapping experiments, BSA MAR-AB and BSA MR-VL, were performed. Two QTLs on chromosome 1 were associated with FBO resistance in each mapping experiment. At the second QTL of BSA MAR-AB, several cytochrome P450 monooxygenase (CYP) genes were located, including CYP392E4, CYP392E6 and CYP392E11, the latter being overexpressed in MAR-AB. Synergism tests further implied a role for CYPs in FBO resistance. Subunit c of mitochondrial ATP-synthase was located near the first QTL of both mapping experiments and harbored a unique V89A mutation enriched in the resistant parents and selected BSA populations. Marker-assisted introgression into a susceptible strain demonstrated a moderate but significant effect of the V89A mutation on toxicity of organotin acaricides. The impact of the mutation on organotin inhibition of ATP synthase was also functionally confirmed by ATPase assays on mitochondrial preparations. To conclude, our findings suggest that FBO resistance in the spider mite T. urticae is a complex interplay between CYP-mediated detoxification and target-site resistance.
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Affiliation(s)
- Berdien De Beer
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Ernesto Villacis-Perez
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium; Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam (UvA), Science Park 904, 1908, XH, Amsterdam, the Netherlands
| | - Mousaalreza Khalighi
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | | | - Marilou Vandenhole
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Wim Jonckheere
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Ibrahim Ismaeil
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Sven Geibel
- Bayer AG, CropScience Division, 40789, Monheim, Germany
| | - Thomas Van Leeuwen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
| | - Wannes Dermauw
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium; Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Plant Sciences Unit, Burgemeester Van Gansberghelaan 96, 9820, Merelbeke, Belgium.
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2
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The therapeutic potential of mitochondrial toxins. J Antibiot (Tokyo) 2021; 74:696-705. [PMID: 34163026 DOI: 10.1038/s41429-021-00436-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/11/2021] [Accepted: 05/11/2021] [Indexed: 02/06/2023]
Abstract
When screening active compounds by phenotypic assays, we often encounter mitochondrial toxins, which are compounds that can affect mitochondrial functions. In normal cells, these toxins may have relatively low toxicity but can nonetheless show measurable effects even at low concentrations. On the other hand, in animals, mitochondrial toxins can exert severe toxicity. Mitochondrial toxins that act as inhibitors of respiratory chain complexes in oxidative phosphorylation (OXPHOS) are typically avoided during drug discovery efforts, as such compounds can directly promote lethal inhibition of pulmonary respiration. However, mitochondrial toxins could in fact have beneficial therapeutic effects. Anti-cancer strategies that target mitochondrial functions, particularly OXPHOS, have received increasing attention in recent years. In this review article we examine the significance of OXPHOS inhibitors as anti-cancer drug candidates and discuss compounds having microbial origins.
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Adeyemi JO, Onwudiwe DC. Organotin(IV) Dithiocarbamate Complexes: Chemistry and Biological Activity. Molecules 2018; 23:E2571. [PMID: 30304779 PMCID: PMC6222534 DOI: 10.3390/molecules23102571] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 10/04/2018] [Accepted: 10/04/2018] [Indexed: 11/16/2022] Open
Abstract
Significant attention has been given to organotin(IV) dithiocabamate compounds in recent times. This is due to their ability to stabilize specific stereochemistry in their complexes, and their diverse application in agriculture, biology, catalysis and as single source precursors for tin sulfide nanoparticles. These complexes have good coordination chemistry, stability and diverse molecular structures which, thus, prompt their wide range of biological activities. Their unique stereo-electronic properties underline their relevance in the area of medicinal chemistry. Organotin(IV) dithiocabamate compounds owe their functionalities and usefulness to the individual properties of the organotin(IV) and the dithiocarbamate moieties present within the molecule. These individual properties create a synergy of action in the hybrid complex, prompting an enhanced biological activity. In this review, we discuss the chemistry of organotin(IV) dithiocarbamate complexes that accounts for their relevance in biology and medicine.
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Affiliation(s)
- Jerry O Adeyemi
- Material Science Innovation and Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Science, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa.
- Department of Chemistry, Faculty of Natural and Agricultural Science, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa.
| | - Damian C Onwudiwe
- Material Science Innovation and Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Science, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa.
- Department of Chemistry, Faculty of Natural and Agricultural Science, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa.
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4
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Orlandi I, Stamerra G, Strippoli M, Vai M. During yeast chronological aging resveratrol supplementation results in a short-lived phenotype Sir2-dependent. Redox Biol 2017; 12:745-754. [PMID: 28412652 PMCID: PMC5397018 DOI: 10.1016/j.redox.2017.04.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 04/05/2017] [Accepted: 04/08/2017] [Indexed: 01/13/2023] Open
Abstract
Resveratrol (RSV) is a naturally occurring polyphenolic compound endowed with interesting biological properties/functions amongst which are its activity as an antioxidant and as Sirtuin activating compound towards SIRT1 in mammals. Sirtuins comprise a family of NAD+-dependent protein deacetylases that are involved in many physiological and pathological processes including aging and age-related diseases. These enzymes are conserved across species and SIRT1 is the closest mammalian orthologue of Sir2 of Saccharomyces cerevisiae. In the field of aging researches, it is well known that Sir2 is a positive regulator of replicative lifespan and, in this context, the RSV effects have been already examined. Here, we analyzed RSV effects during chronological aging, in which Sir2 acts as a negative regulator of chronological lifespan (CLS). Chronological aging refers to quiescent cells in stationary phase; these cells display a survival-based metabolism characterized by an increase in oxidative stress. We found that RSV supplementation at the onset of chronological aging, namely at the diauxic shift, increases oxidative stress and significantly reduces CLS. CLS reduction is dependent on Sir2 presence both in expired medium and in extreme Calorie Restriction. In addition, all data point to an enhancement of Sir2 activity, in particular Sir2-mediated deacetylation of the key gluconeogenic enzyme phosphoenolpyruvate carboxykinase (Pck1). This leads to a reduction in the amount of the acetylated active form of Pck1, whose enzymatic activity is essential for gluconeogenesis and CLS extension.
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Affiliation(s)
- Ivan Orlandi
- SYSBIO Centre for Systems Biology Milano, Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy.
| | - Giulia Stamerra
- SYSBIO Centre for Systems Biology Milano, Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy.
| | - Maurizio Strippoli
- SYSBIO Centre for Systems Biology Milano, Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy.
| | - Marina Vai
- SYSBIO Centre for Systems Biology Milano, Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy.
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5
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Niu L, Li Y, Li Q. Medicinal properties of organotin compounds and their limitations caused by toxicity. Inorganica Chim Acta 2014. [DOI: 10.1016/j.ica.2014.05.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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García-Carrillo S, Aranda FJ, Ortiz A, Teruel JA. Interaction of trialkyltin(IV) chlorides with sarcoplasmic reticulum calcium ATPase. Appl Organomet Chem 2012. [DOI: 10.1002/aoc.2903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Scheherezade García-Carrillo
- Departamento de Bioquímica y Biología Molecular A, Facultad de Veterinaria; Universidad de Murcia; 30100 Espinardo Murcia Spain
| | - Francisco J. Aranda
- Departamento de Bioquímica y Biología Molecular A, Facultad de Veterinaria; Universidad de Murcia; 30100 Espinardo Murcia Spain
| | - Antonio Ortiz
- Departamento de Bioquímica y Biología Molecular A, Facultad de Veterinaria; Universidad de Murcia; 30100 Espinardo Murcia Spain
| | - José A. Teruel
- Departamento de Bioquímica y Biología Molecular A, Facultad de Veterinaria; Universidad de Murcia; 30100 Espinardo Murcia Spain
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Yoboue ED, Augier E, Galinier A, Blancard C, Pinson B, Casteilla L, Rigoulet M, Devin A. cAMP-induced mitochondrial compartment biogenesis: role of glutathione redox state. J Biol Chem 2012; 287:14569-78. [PMID: 22396541 DOI: 10.1074/jbc.m111.302786] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Cell fate and proliferation are tightly linked to the regulation of the mitochondrial energy metabolism. Hence, mitochondrial biogenesis regulation, a complex process that requires a tight coordination in the expression of the nuclear and mitochondrial genomes, has a major impact on cell fate and is of high importance. Here, we studied the molecular mechanisms involved in the regulation of mitochondrial biogenesis through a nutrient-sensing pathway, the Ras-cAMP pathway. Activation of this pathway induces a decrease in the cellular phosphate potential that alleviates the redox pressure on the mitochondrial respiratory chain. One of the cellular consequences of this modulation of cellular phosphate potential is an increase in the cellular glutathione redox state. The redox state of the glutathione disulfide-glutathione couple is a well known important indicator of the cellular redox environment, which is itself tightly linked to mitochondrial activity, mitochondria being the main cellular producer of reactive oxygen species. The master regulator of mitochondrial biogenesis in yeast (i.e. the transcriptional co-activator Hap4p) is positively regulated by the cellular glutathione redox state. Using a strain that is unable to modulate its glutathione redox state (Δglr1), we pinpoint a positive feedback loop between this redox state and the control of mitochondrial biogenesis. This is the first time that control of mitochondrial biogenesis through glutathione redox state has been shown.
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Affiliation(s)
- Edgar D Yoboue
- CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095, F-33000 Bordeaux, France
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Kotiadis VN, Leadsham JE, Bastow EL, Gheeraert A, Whybrew JM, Bard M, Lappalainen P, Gourlay CW. Identification of new surfaces of cofilin that link mitochondrial function to the control of multi-drug resistance. J Cell Sci 2012; 125:2288-99. [PMID: 22344251 DOI: 10.1242/jcs.099390] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ADF/cofilin family proteins are essential regulators of actin cytoskeletal dynamics. Recent evidence also implicates cofilin in the regulation of mitochondrial function. Here, we identify new functional surfaces of cofilin that are linked with mitochondrial function and stress responses in the budding yeast Saccharomyces cerevisiae. Our data link surfaces of cofilin that are involved in separable activities of actin filament disassembly or stabilisation, to the regulation of mitochondrial morphology and the activation status of Ras, respectively. Importantly, charge alterations to conserved surfaces of cofilin that do not interfere with its actin regulatory activity lead to a dramatic increase in respiratory function that triggers a retrograde signal to upregulate a battery of ABC transporters and concurrent metabolic changes that support multi-drug resistance. We hypothesise that cofilin functions within a bio-sensing system that connects the cytoskeleton and mitochondrial function to environmental challenge.
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Affiliation(s)
- Vassilios N Kotiadis
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, Kent, UK
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Nesci S, Ventrella V, Trombetti F, Pirini M, Pagliarani A. Tributyltin (TBT) and mitochondrial respiration in mussel digestive gland. Toxicol In Vitro 2011; 25:951-9. [DOI: 10.1016/j.tiv.2011.03.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 03/01/2011] [Accepted: 03/03/2011] [Indexed: 10/18/2022]
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10
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Deletion or overexpression of mitochondrial NAD+ carriers in Saccharomyces cerevisiae alters cellular NAD and ATP contents and affects mitochondrial metabolism and the rate of glycolysis. Appl Environ Microbiol 2011; 77:2239-46. [PMID: 21335394 DOI: 10.1128/aem.01703-10] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The modification of enzyme cofactor concentrations can be used as a method for both studying and engineering metabolism. We varied Saccharomyces cerevisiae mitochondrial NAD levels by altering expression of its specific mitochondrial carriers. Changes in mitochondrial NAD levels affected the overall cellular concentration of this coenzyme and the cellular metabolism. In batch culture, a strain with a severe NAD depletion in mitochondria succeeded in growing, albeit at a low rate, on fully respiratory media. Although the strain increased the efficiency of its oxidative phosphorylation, the ATP concentration was low. Under the same growth conditions, a strain with a mitochondrial NAD concentration higher than that of the wild type similarly displayed a low cellular ATP level, but its growth rate was not affected. In chemostat cultures, when cellular metabolism was fully respiratory, both mutants showed low biomass yields, indicative of impaired energetic efficiency. The two mutants increased their glycolytic fluxes, and as a consequence, the Crabtree effect was triggered at lower dilution rates. Strikingly, the mutants switched from a fully respiratory metabolism to a respirofermentative one at the same specific glucose flux as that of the wild type. This result seems to indicate that the specific glucose uptake rate and/or glycolytic flux should be considered one of the most important independent variables for establishing the long-term Crabtree effect. In cells growing under oxidative conditions, bioenergetic efficiency was affected by both low and high mitochondrial NAD availability, which suggests the existence of a critical mitochondrial NAD concentration in order to achieve optimal mitochondrial functionality.
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11
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Ventrella V, Nesci S, Trombetti F, Bandiera P, Pirini M, Borgatti AR, Pagliarani A. Tributyltin inhibits the oligomycin-sensitive Mg-ATPase activity in Mytilus galloprovincialis digestive gland mitochondria. Comp Biochem Physiol C Toxicol Pharmacol 2011; 153:75-81. [PMID: 20826230 DOI: 10.1016/j.cbpc.2010.08.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 08/19/2010] [Accepted: 08/30/2010] [Indexed: 11/19/2022]
Abstract
Tributyltin (TBT), widely employed in the past in antifouling paints, is one of the most toxic organic pollutants. Although recently banned, it still threatens coastal water ecosystems and accumulates in filter-feeding molluscs. TBT is known to act as a membrane-active toxicant; however data on mussels are scanty and exposure effects on mitochondrial ATPase activities remain hitherto unexplored. TBT effects on the mitochondrial Mg-ATPase activities in the digestive gland of Mytilus galloprovincialis were investigated both in vitro and in TBT-exposed mussels. Both an oligomycin-sensitive Mg-ATPase (OS Mg-ATPase) (70% of total Mg-ATPase activity) and an oligomycin-insensitive ATPase (OI Mg-ATPase) (30%) were found. The OS-Mg-ATPase was as much as 70% in vitro inhibited by 0.7 μM (203 μg/L) TBT, while higher concentrations promoted a partial inhibition release up to 5.0 μM TBT; higher than 10.0 μM TBT concentrations yielded nearly complete enzyme inhibition. Concentrations higher than 1 μM TBT enhanced the OI Mg-ATPase. Mussels exposed to 0.5 and 1.0 μg/L TBT in aquaria showed a 30% depressed OS Mg-ATPase activity, irrespective of TBT dose and exposure time (24 and 120 h). The OI Mg-ATPase activity was apparently refractory to TBT exposure and halved both in control and TBT-exposed mussels after 120 h exposure.
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Affiliation(s)
- Vittoria Ventrella
- Department of Biochemistry "G. Moruzzi", Section of Veterinary Biochemistry, University of Bologna, Via Tolara di sopra, 50-40064 Ozzano Emilia (BO), Italy.
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12
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Leadsham JE, Gourlay CW. cAMP/PKA signaling balances respiratory activity with mitochondria dependent apoptosis via transcriptional regulation. BMC Cell Biol 2010; 11:92. [PMID: 21108829 PMCID: PMC3001716 DOI: 10.1186/1471-2121-11-92] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 11/25/2010] [Indexed: 12/31/2022] Open
Abstract
Background Appropriate control of mitochondrial function, morphology and biogenesis are crucial determinants of the general health of eukaryotic cells. It is therefore imperative that we understand the mechanisms that co-ordinate mitochondrial function with environmental signaling systems. The regulation of yeast mitochondrial function in response to nutritional change can be modulated by PKA activity. Unregulated PKA activity can lead to the production of mitochondria that are prone to the production of ROS, and an apoptotic form of cell death. Results We present evidence that mitochondria are sensitive to the level of cAMP/PKA signaling and can respond by modulating levels of respiratory activity or committing to self execution. The inappropriate activation of one of the yeast PKA catalytic subunits, Tpk3p, is sufficient to commit cells to an apoptotic death through transcriptional changes that promote the production of dysfunctional, ROS producing mitochondria. Our data implies that cAMP/PKA regulation of mitochondrial function that promotes apoptosis engages the function of multiple transcription factors, including HAP4, SOK2 and SCO1. Conclusions We propose that in yeast, as is the case in mammalian cells, mitochondrial function and biogenesis are controlled in response to environmental change by the concerted regulation of multiple transcription factors. The visualization of cAMP/TPK3 induced cell death within yeast colonies supports a model that PKA regulation plays a physiological role in coordinating respiratory function and cell death with nutritional status in budding yeast.
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Affiliation(s)
- Jane E Leadsham
- Department of Biosciences, University of Kent, Canterbury Kent, England, UK
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ARTIKA IMADE. Bioenergetic Consequences of FLAG Tag Addition to the C-Terminus of Subunit 8 of Yeast Saccharomyces cerevisiae Mitochondrial ATP Synthase. HAYATI JOURNAL OF BIOSCIENCES 2010. [DOI: 10.4308/hjb.17.3.151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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14
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Pagliarani A, Bandiera P, Ventrella V, Trombetti F, Pirini M, Nesci S, Borgatti AR. Tributyltin (TBT) inhibition of oligomycin-sensitive Mg-ATPase activity in mussel mitochondria. Toxicol In Vitro 2008; 22:827-36. [DOI: 10.1016/j.tiv.2007.12.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 12/07/2007] [Accepted: 12/21/2007] [Indexed: 11/30/2022]
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Buck-Koehntop BA, Porcelli F, Lewin JL, Cramer CJ, Veglia G. Biological chemistry of organotin compounds: Interactions and dealkylation by dithiols. J Organomet Chem 2006. [DOI: 10.1016/j.jorganchem.2005.12.047] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Ueno H, Suzuki T, Kinosita K, Yoshida M. ATP-driven stepwise rotation of FoF1-ATP synthase. Proc Natl Acad Sci U S A 2005; 102:1333-8. [PMID: 15668386 PMCID: PMC545493 DOI: 10.1073/pnas.0407857102] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
FoF1-ATP synthase (FoF1) is a motor enzyme that couples ATP synthesis/hydrolysis with a transmembrane proton translocation. F1, a water-soluble ATPase portion of FoF1, rotates by repeating ATP-waiting dwell, 80 degrees substep rotation, catalytic dwell, and 40 degrees -substep rotation. Compared with F1, rotation of FoF1 has yet been poorly understood, and, here, we analyzed ATP-driven rotations of FoF1. Rotation was probed with an 80-nm bead attached to the ring of c subunits in the immobilized FoF1 and recorded with a submillisecond fast camera. The rotation rates at various ATP concentrations obeyed the curve defined by a Km of approximately 30 microM and a Vmax of approximately 350 revolutions per second (at 37 degrees C). At low ATP, ATP-waiting dwell was seen and the kon-ATP was estimated to be 3.6 x 10(7) M(-1) x s(-1). At high ATP, fast, poorly defined stepwise motions were observed that probably reflect the catalytic dwells. When a slowly hydrolyzable substrate, adenosine 5'-[gamma-thio]triphosphate, was used, the catalytic dwells consisting of two events were seen more clearly at the angular position of approximately 80 degrees . The rotational behavior of FoF1 resembles that of F1. This finding indicates that "friction" in Fo motor is negligible during the ATP-driven rotation. Tributyltin chloride, a specific inhibitor of proton translocation, slowed the rotation rate by 96%. However, dwells at clearly defined angular positions were not observed under these conditions, indicating that inhibition by tributyltin chloride is complex.
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Affiliation(s)
- Hiroshi Ueno
- Chemical Resources Laboratory, Tokyo Institute of Technology, Nagatsuta 4259, Yokohama 226-8503, Japan
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von Ballmoos C, Brunner J, Dimroth P. The ion channel of F-ATP synthase is the target of toxic organotin compounds. Proc Natl Acad Sci U S A 2004; 101:11239-44. [PMID: 15277681 PMCID: PMC509188 DOI: 10.1073/pnas.0402869101] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
ATP is the universal energy currency of living cells, and the majority of it is synthesized by the F1F0 ATP synthase. Inhibitors of this enzyme are therefore potentially detrimental for all life forms. Tributyltin chloride (TBT-Cl) inhibits ATP hydrolysis by the Na(+)-translocating ATP synthase of Ilyobacter tartaricus or the H(+)-translocating counterpart of Escherichia coli with apparent Ki of 200 nM. To target the site of this inhibition, we synthesized a tritium-labeled derivative of TBT-Cl in which one of the butyl groups was replaced by a photoactivatable aryldiazirine residue. Upon illumination, subunit a of the ATP synthase becomes specifically modified, and this labeling is suppressed in the presence of the original inhibitor. In case of the Na+ ATP synthase, labeling is also suppressed in the presence of Na+ ions, suggesting an interference in Na+ or TBT-Cl binding to subunit a. This interference is corroborated by the protection of ATP hydrolysis from TBT-Cl inhibition by 105 mM Na+. TBT-Cl strongly inhibits Na+ exchange by the reconstituted I. tartaricus ATP synthase. Taken together these results indicate that the subunit a ion channel is the target site for ATPase inhibition by toxic organotin compounds. An inhibitor interacting specifically with this site has not been reported previously.
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Affiliation(s)
- Christoph von Ballmoos
- Institut für Mikrobiologie der Eidgenössischen Technischen Hochschule, ETH Zentrum, CH-8092 Zürich, Switzerland
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Hlavatá L, Aguilaniu H, Pichová A, Nyström T. The oncogenic RAS2(val19) mutation locks respiration, independently of PKA, in a mode prone to generate ROS. EMBO J 2003; 22:3337-45. [PMID: 12839995 PMCID: PMC165639 DOI: 10.1093/emboj/cdg314] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The RAS2(val19) allele, which renders the cAMP-PKA pathway constitutively active and decreases the replicative life-span of yeast cells, is demonstrated to increase production of reactive oxygen species (ROS) and to elevate oxidative protein damage. Mitochondrial respiration in the mutant is locked in a non-phosphorylating mode prone to generate ROS but this phenotype is not linked to a constitutively active PKA pathway. In contrast, providing RAS2(val19) cells with the mammalian uncoupling protein UCP1 restores phosphorylating respiration and reduces ROS levels, but does not correct for PKA-dependent defects. Thus, the RAS2(val19) allele acts like a double-edged sword with respect to oxidation management: (i). it diminishes expression of STRE element genes required for oxidative stress defenses in a PKA-dependent fashion, and (ii). it affects endogenous ROS production and the respiratory state in a PKA-independent way. The effect of the oncogenic RAS allele on the replicative life-span is primarily asserted via the PKA-dependent pathway since Pde2p, but not UCP1, overproduction suppressed premature aging of the RAS2(val19) mutant.
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Affiliation(s)
- Lydie Hlavatá
- Institute of Microbiology, Czech Academy of Sciences, CZ-142 20 Prague, Czech Republic
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19
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Skarning CRF, Varhaug LN, Fonnum F, Osmundsen H. Effects of in vivo treatment of rats with trimethyltin chloride on respiratory properties of rat liver mitochondria. Biochem Pharmacol 2002; 64:657-67. [PMID: 12167485 DOI: 10.1016/s0006-2952(02)01182-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Liver mitochondria isolated from rats treated in vivo with trimethyltin chloride show stimulation of respiration using glutamate/malate as substrate, and a transient inhibition on rates of respiration using palmitoyl-L-carnitine as substrate. This phenomenon was observed with both ADP- and FCCP-stimulated respiration. In contrast, rates of respiration by liver mitochondria isolated from rats treated in vivo with trimethyltin chloride, following prior treatment with clofibrate, were inhibited when glutamate/malate was respiratory substrates. With palmitoyl-L-carnitine no effect of trimethyltin chloride was observed. In vitro treatment of rat liver mitochondria, or of rat liver homogenates, led to the expected, powerful inhibition of respiration. The synthesis of ATP by liver mitochondria isolated from rats treated in vivo with trimethyltin chloride was not inhibited compared to mitochondria isolated from control rats. Similarly, ATP synthesis by mitochondria isolated from rats treated with clofibrate, before treatment with trimethyltin chloride, was not inhibited. We, therefore, conclude that the powerful inhibitory effects of trimethyltin found in vitro, is not expressed in vivo during the first 36 hr following administration. In vivo treatment of rats with trimethyltin chloride caused a marked increase in hepatic levels of taurine and glycine, while levels of glutathione and glutamine were diminished. This is consistent with an enhanced oxidative stress in the liver. Our findings lead to the conclusion that increased oxidative stress, rather than inhibition of the mitochondrial ATPase, is a likely major cause of the in vivo toxic effects due to trimethyltin chloride.
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Dejean L, Beauvoit B, Alonso AP, Bunoust O, Guérin B, Rigoulet M. cAMP-induced modulation of the growth yield of Saccharomyces cerevisiae during respiratory and respiro-fermentative metabolism. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1554:159-69. [PMID: 12160989 DOI: 10.1016/s0005-2728(02)00240-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The aim of this study was to investigate the effects of an overactivation of the cAMP/protein kinase A signaling pathway on the energetic metabolism of growing yeast. By using a cAMP-permeant mutant strain, we show that the rise in intracellular cAMP activates both anabolic and catabolic pathways. Indeed, different physiological patterns were observed with respect to the growth condition: (i) When cells were grown with a limiting amount of lactate, cAMP addition markedly increased the growth rate, whereas it only slightly increased the mitochondrial and cellular protein content. In parallel, the respiratory rate increased and the growth yield, as assessed by direct microcalorimetry, was not significantly modified by cAMP. (ii) Under conditions where the growth rate was already optimal (high lactate concentration), exogenous cAMP led to a proliferation of well-coupled mitochondria within cells and to an accumulation of cellular and mitochondrial proteins. This phenomenon was associated with a rise in the respiratory activity, thus leading to a drop in the growth yield. (iii) Under conditions of catabolic repression (high glucose concentration), cAMP addition markedly increased the fermentation rate and decreased the growth yield. It is concluded that overactivation of the cAMP/PKA pathway leads to uncoupling between biomass synthesis and catabolism, under conditions where an optimal growth rate is sustained by either a fermentative or a respiratory metabolism.
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Affiliation(s)
- Laurent Dejean
- Institut de Biochimie et Génétique Cellulaires du CNRS, Université Victor Ségalen-Bordeaux 2, 1 rue Camille Saint Saëns, 33077 cedex, Bordeaux, France
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21
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Aguilaniu H, Gustafsson L, Rigoulet M, Nyström T. Protein oxidation in G0 cells of Saccharomyces cerevisiae depends on the state rather than rate of respiration and is enhanced in pos9 but not yap1 mutants. J Biol Chem 2001; 276:35396-404. [PMID: 11431467 DOI: 10.1074/jbc.m101796200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Immunodetection of protein carbonyl groups demonstrates that growth arrest elicited by carbon or nitrogen starvation causes an increased oxidation of proteins in Saccharomyces cerevisiae. Mutant analysis suggests that the response regulator Pos9p is involved in mitigating self-inflicted oxidative damages in G(0) cells, whereas Yap1p is primarily required in growing cells. The data also suggest that oxidation of target proteins is not a priori an effect of arrest of cell division or nutrient depletion and cannot be explained by the respiratory activity alone nor a high ratio of catabolic/anabolic activity in G(0) cells. Instead, we observed that starvation elicits a transition in the respiratory state (from phosphorylating to nonphosphorylating respiration) and that this transition is associated with a stepwise increase in protein oxidation. During carbon starvation, this transition and increase in oxidation occurs immediately as the carbon source is depleted, growth is arrested, and the respiratory rate falls drastically. In contrast, during nitrogen starvation and excess carbon the respiratory state transition and stepwise increase in protein oxidation are markedly delayed and occur long after the nitrogen source has been depleted and division and growth-arrested. Oxidation in G(0) cells could be enhanced by treating cells with low concentrations of antimycin A and attenuated with myxothiazol, indicating that protein oxidation is intimately linked to reactive oxygen species generated by semiquinones of the Q-cycle. Thus, the work presented suggests that the degree of coupling in the mitochondrial respiratory apparatus rather then the overall rate of respiration affects the degree of protein oxidation in nondividing yeast cells.
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Affiliation(s)
- H Aguilaniu
- Department of Molecular Biotechnology, Chalmers University of Technology, Box 462, SE-405 30 Göteborg, Sweden
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22
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Nishikimi A, Kira Y, Kasahara E, Sato EF, Kanno T, Utsumi K, Inoue M. Tributyltin interacts with mitochondria and induces cytochrome c release. Biochem J 2001; 356:621-6. [PMID: 11368793 PMCID: PMC1221877 DOI: 10.1042/0264-6021:3560621] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Although triorganotins are potent inducers of apoptosis in various cell types, the critical targets of these compounds and the mechanisms by which they lead to cell death remain to be elucidated. There are two major pathways by which apoptotic cell death occurs: one is triggered by a cytokine mediator and the other is by a mitochondrion-dependent mechanism. To elucidate the mechanism of triorganotin-induced apoptosis, we studied the effect of tributyltin on mitochondrial function. We found that moderately low doses of tributyltin decrease mitochondrial membrane potential and induce cytochrome c release by a mechanism inhibited by cyclosporine A and bongkrekic acid. Tributyltin-induced cytochrome c release is also prevented by dithiols such as dithiothreitol and 2,3-dimercaptopropanol but not by monothiols such as GSH, N-acetyl-L-cysteine, L-cysteine and 2-mercaptoethanol. Further studies with phenylarsine oxide agarose revealed that tributyltin interacts with the adenine nucleotide translocator, a functional constituent of the mitochondrial permeability transition pore, which is selectively inhibited by dithiothreitol. These results suggest that, at low doses, tributyltin interacts selectively with critical thiol residues in the adenine nucleotide translocator and opens the permeability transition pore, thereby decreasing membrane potential and releasing cytochrome c from mitochondria, a series of events consistent with established mechanistic models of apoptosis.
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Affiliation(s)
- A Nishikimi
- Department of Biochemistry and Molecular Pathology, Osaka City University Medical School, Osaka 545-8585, Japan
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Dejean L, Beauvoit B, Bunoust O, Fleury C, Guérin B, Rigoulet M. The calorimetric-respirometric ratio is an on-line marker of enthalpy efficiency of yeast cells growing on a non-fermentable carbon source. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1503:329-40. [PMID: 11115644 DOI: 10.1016/s0005-2728(00)00210-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Although on-line calorimetry has been widely used to detect transitions in global metabolic activity during the growth of microorganisms, the relationships between oxygen consumption flux and heat production are poorly documented. In this work, we developed a respirometric and calorimetric approach to determine the enthalpy efficiency of respiration-linked energy transformation of isolated yeast mitochondria and yeast cells under growing and resting conditions. On isolated mitochondria, the analysis of different phosphorylating and non-phosphorylating steady states clearly showed that the simultaneous measurements of heat production and oxygen consumption rates can lead to the determination of both the enthalpy efficiency and the ATP/O yield of oxidative phosphorylation. However, these determinations were made possible only when the net enthalpy change associated with the phosphorylating system was different from zero. On whole yeast cells, it is shown that the simultaneous steady state measurements of the heat production and oxygen consumption rates allow the enthalpy growth efficiency (i.e. the amount of energy conserved as biomass compared to the energy utilised for complete catabolism plus anabolism) to be assessed. This method is based on the comparison between the calorimetric-respirometric ratio (CR ratio) determined under growth versus resting conditions during a purely aerobic metabolism. Therefore, in contrast to the enthalpy balance approach, this method does not rely on the exhaustive and tedious determinations of the metabolites and elemental composition of biomass. Thus, experiments can be performed in the presence of non-limiting amounts of carbon substrate, an approach which has been successfully applied to slow growing cells such as yeast cells expressing wild-type or a mutant rat uncoupling protein-1.
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Affiliation(s)
- L Dejean
- Institut de Biochimie et Génétique Cellulaires du CNRS, Université Bordeaux 2, France
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Matsuya H, Okamoto M, Ochi T, Nishikawa A, Shimizu S, Kataoka T, Nagai K, Wasserman HH, Ohkuma S. Reversible and potent uncoupling of hog gastric (H(+)+K(+))-ATPase by prodigiosins. Biochem Pharmacol 2000; 60:1855-63. [PMID: 11108801 DOI: 10.1016/s0006-2952(00)00509-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Prodigiosin, prodigiosin 25-C, and metacycloprodigiosin all strongly inhibited the acidification activity of (H(+)+K(+))-ATPase on membrane vesicles from hog gastric mucosa (IC(50) = 32 to 103 pmol/mg protein). But, the prodigiosins, unlike omeprazole, showed little inhibitory effect on K(+)-dependent ATPase (K(+)-ATPase) activity, although at higher concentrations they inhibited K(+)-ATPase activity with an IC(50) of 1.5 to 3.0 microM. Furthermore, the inhibitory effect of the prodigiosins was rapid and completely reversible unlike that of omeprazole, and the mode of inhibition was non-competitive with respect to ATP. Hog gastric (H(+)+K(+))-ATPase itself showed an absolute requirement of halide (effectively, chloride) for acidification activity. Prodigiosins also showed a chloride requirement for inhibition of vesicular acidification, and quickly reversed the acidification of vesicular pH to neutrality even in the presence of N, N'-dicyclohexylcarbodiimide (DCCD), showing their ionophoric nature of acidification inhibitory activity. In fact, tributyltin chloride (TBT, an OH(-)/Cl(-) exchange ionophore) also inhibited vesicular acidification, but it inhibited K(+)-ATPase activity too. Finally, the prodigiosins inhibited the acid secretion from parietal cells isolated from rabbit gastric mucosa. These results suggest that prodigiosins are potent reversible uncouplers of (H(+)+K(+))-ATPase that inhibit gastric acid secretion.
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Affiliation(s)
- H Matsuya
- Laboratory of Biochemistry, Department of Molecular and Cellular Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, 920-0934, Ishikawa, Japan
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26
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Dejean L, Beauvoit B, Guérin B, Rigoulet M. Growth of the yeast Saccharomyces cerevisiae on a non-fermentable substrate: control of energetic yield by the amount of mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1457:45-56. [PMID: 10692549 DOI: 10.1016/s0005-2728(00)00053-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The purpose of this study was to investigate the long-term control of ATP synthesis during the course of Saccharomyces cerevisiae batch grown on lactate, a purely respiratory substrate. For this, we used a respirometric and on-line calorimetric approach to analyse the energetic balances and the control of energetic metabolism during growth. Enthalpic growth yields assessed by enthalpy balance (taking account of substrate consumption, by-product accumulation, biomass formation and heat dissipation) remained constant during the entire exponential growth. Moreover, at the same time, a parallel decrease in basal respiratory rate and enthalpy flux occurred. It is shown that the decrease in respiration corresponds to a decrease in the amount of mitochondria per cell but not to a change of steady state of oxidative phosphorylation. Taking into account the part of energy used for maintenance, it can be concluded that mitochondria by themselves are the major heat dissipative system in a fully aerobic metabolism, and that the decrease in the amount of mitochondria when growth rate decreases leads to an enthalpic growth yield constant.
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Affiliation(s)
- L Dejean
- Institut de Biochimie et Génétique Cellulaires du CNRS, Université Victor Segalen, Bordeaux II, 1 rue Camille Saint Saëns, 33077, Bordeaux, France
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27
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Golin J, Barkatt A, Cronin S, Eng G, May L. Chemical specificity of the PDR5 multidrug resistance gene product of Saccharomyces cerevisiae based on studies with tri-n-alkyltin chlorides. Antimicrob Agents Chemother 2000; 44:134-8. [PMID: 10602734 PMCID: PMC89639 DOI: 10.1128/aac.44.1.134-138.2000] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To understand the chemical basis of action for the PDR5-encoded multidrug resistance transporter of Saccharomyces cerevisiae, we compared the relative hypersensitivities of the wild-type (RW2802) and null mutant strains toward a series of tri-n-alkyltin compounds. These compounds differ from each other in a systematic fashion-either by hydrocarbon chain length or by anion composition. Using zone-of-inhibition and fixed-concentration assays, we found that the ethyl, propyl, and butyl compounds are strong PDR5 substrates, whereas the methyl and pentyl compounds are weak. We conclude that hydrophobicity and anion makeup are relatively unimportant factors in determining whether a tri-n-alkyltin compound is a good PDR5 substrate but that the dissociation of the compound and the molecular size are significant.
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Affiliation(s)
- J Golin
- Departments of Biology, The Catholic University of America, Washington, D.C. 20064, USA.
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28
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Stridh H, Fava E, Single B, Nicotera P, Orrenius S, Leist M. Tributyltin-induced apoptosis requires glycolytic adenosine trisphosphate production. Chem Res Toxicol 1999; 12:874-82. [PMID: 10525261 DOI: 10.1021/tx990041c] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The toxicity of tributyltin chloride (TBT) involves Ca(2+) overload, cytoskeletal damage, and mitochondrial failure leading to cell death by apoptosis or necrosis. Here, we examined whether the intracellular ATP level modulates the mode of cell death after exposure to TBT. When Jurkat cells were energized by the mitochondrial substrate, pyruvate, low concentrations of TBT (1-2 microM) triggered an immediate depletion of intracellular ATP followed by necrotic death. When ATP levels were maintained by the addition of glucose, the mode of cell death was typically apoptotic. Glycolytic ATP production was required for apoptosis at two distinct steps. First, maintenance of adequate ATP levels accelerated the decrease of mitochondrial membrane potential, and the release of the intermembrane proteins adenylate kinase and cytochrome c from mitochondria. A possible role of the adenine nucleotide exchanger in this first ATP-dependent step is suggested by experiments performed with the specific inhibitor, bongkrekic acid. This substance delayed cytochrome c release in a manner similar to that caused by ATP depletion. Second, caspase activation following cytochrome c release was only observed in ATP-containing cells. Bcl-2 had only a minor effect on TBT-triggered caspase activation or cell death. We conclude that intracellular ATP concentrations control the mode of cell death in TBT-treated Jurkat cells at both the mitochondrial and caspase activation levels.
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Affiliation(s)
- H Stridh
- Institute of Environmental Medicine, Division of Toxicology, Karolinska Institutet, Box 210, S-171 77 Stockholm, Sweden
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29
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Hinz W, Faller B, Grüninger S, Gazzotti P, Chiesi M. Recombinant human uncoupling protein-3 increases thermogenesis in yeast cells. FEBS Lett 1999; 448:57-61. [PMID: 10217410 DOI: 10.1016/s0014-5793(99)00331-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The long form of human uncoupling protein-3 (hUCP3L) is highly homologous to thermogenin (UCPI), the uncoupling protein of brown fat mitochondria, but is expressed predominantly in skeletal muscle. Its putative role is to regulate the coupling efficiency of oxidative phosphorylation and thus thermogenesis in skeletal muscle, a major thermogenic tissue in higher mammals. To study the functional relevance of hUCP3L, the protein was expressed in yeast cells under the control of the galactose promoter. Expression of hUCP3L induced a series of phenotype changes in the yeast cells. The cellular growth and the mitochondrial membrane potential were both diminished. The portion of cellular respiration coupled to oxidative phosphorylation decreased from 57% to 11% (P<0.001) and the cellular heat production, as measured by direct microcalorimetry, was increased by 33.3 +/- 3.2% (P<0.001) after induction of UCP3L. These observations demonstrate for the first time the intrinsic thermogenic properties of hUCP3L in intact cells.
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Affiliation(s)
- W Hinz
- Department of Metabolic and Cardiovascular Disease, Novartis Pharma AG, Basel, Switzerland
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30
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Sato T, Konno H, Tanaka Y, Kataoka T, Nagai K, Wasserman HH, Ohkuma S. Prodigiosins as a new group of H+/Cl- symporters that uncouple proton translocators. J Biol Chem 1998; 273:21455-62. [PMID: 9705273 DOI: 10.1074/jbc.273.34.21455] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We reported previously (Kataoka, T., Muroi, M., Ohkuma, S., Waritani, T., Magae, J., Takatsuki, A., Kondo, S., Yamasaki, M., and Nagai, K. (1995) FEBS Lett. 359, 53-59) that prodigiosin 25-C uncoupled vacuolar H+-ATPase, inhibited vacuolar acidification, and affected glycoprotein processing. In the present study we show that prodigiosins (prodigiosin, metacycloprodigiosin, and prodigiosin 25-C) inhibit the acidification activity of H+-ATPase chloride dependently, but not membrane potential formation or ATP hydrolysis activity, and suggest that they promote H+/Cl- symport (or OH-/Cl- exchange, in its equivalence) across vesicular membranes. In fact, prodigiosins displayed H+/Cl- symport activity on liposomal membranes. First of all, they decreased the internal pH of liposomes depending on the external chloride, and raised it depending on the internal chloride when external buffer was free from chloride. Second, their effect was electroneutral and not seriously affected by the application of an inside positive membrane potential generated by K+ and valinomycin. Finally, they promoted the uptake of [36Cl] from external buffers with concomitant intraliposomal acidification when external pH was acidic relative to liposome interior. As prodigiosins hardly inhibit the catalytic activity (ATP hydrolysis) unlike well known OH-/Cl- exchangers (for example, tributyltin chloride), they should provide powerful tools for the study of molecular machinery and cellular activities involving transport of protons and/or chloride.
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Affiliation(s)
- T Sato
- Laboratory of Biochemistry, Department of Molecular and Cell Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, Takara-machi 13-1, Kanazawa, Ishikawa 920-0934, Japan
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Avéret N, Fitton V, Bunoust O, Rigoulet M, Guérin B. Yeast mitochondrial metabolism: from in vitro to in situ quantitative study. Mol Cell Biochem 1998; 184:67-79. [PMID: 9746313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In this work, we first compared yeast mitochondrial oxidative metabolism at different levels of organization: whole cells (C), spheroplasts (S), permeabilized spheroplasts (PS) or isolated mitochondria (M). At present, S are more suitable for use than C for biochemical techniques such as fast extraction of metabolites and permeabilization. We show here that respiratory rates of S with various substrates are similar to C, which demonstrate that they are adapted to yeast bioenergetic studies. It appeared from ethanol metabolism +/- NAD+ or NADH respiratory rates on PS that ethanol metabolism was largely cytosolic; moreover, the activity of NADH dehydrogenase was lesser in the case of PS than in S. By comparing PS and M, the biggest difference concerned the respiratory rates of pyruvate and pyruvate-malate, which were much lower for M. Thus mitochondria preparation caused an unidentified loss involved directly in pyruvate metabolism. When the respiratory rate was lowered as a consequence of a high kinetic control of oxidative activity upstream from the respiratory chain, a similar correlation between the increase in ATP/O and decrease in respiratory rate was observed. So, the intrinsic uncoupling of proton pumps is not a particularity of M. Secondly, we demonstrate the existence of a mechanism of retarded diffusion in yeast similar to that already observed in permeabilized mammalian cells for ADP. Such a mechanism also occurs in yeast for several respiratory substrates: the K0.5 for each substrate toward the respiration rate in PS always exceeds that for M. It is proposed that such a discrepancy is due to a restriction of metabolite movement across the outer mitochondrial membrane in permeabilized cells, i.e. regulation of the substrate permeability through porin channels. In the porin-deficient yeast mutant, the K0.5 for NADH is not significantly different in either M or PS and is comparable to that of the parent strain PS. This result confirms that this retarded diffusion is essentially due to the opening-closing of the porin channel.
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Affiliation(s)
- N Avéret
- Institut de Biochimie et Génétique Cellulaires du CNRS, Université Victor Ségalen Bordeaux 2, France
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Pélissier P, Camougrand N, Velours G, Guérin M. NCA3, a nuclear gene involved in the mitochondrial expression of subunits 6 and 8 of the Fo-F1 ATP synthase of S. cerevisiae. Curr Genet 1995; 27:409-16. [PMID: 7586026 DOI: 10.1007/bf00311209] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Respiratory-competent nuclear mutants have been isolated which presented a cryosensitive phenotype on a non-fermentative carbon source, due to a dysfunctioning of the mitochondrial F1-Fo ATP synthase which results from a relative defect in subunits 6 and 8 of the Fo sector. Both proteins are mtDNA-encoded, but the defect is due to the simultaneous presence of a mutation in two unlinked nuclear genes (NCA2 and NCA3, for Nuclear Control of ATPase) promoting a modification of the expression of the ATP8-ATP6 co-transcript (formerly denoted AAP1-OLI2). This co-transcript matures at a unique site to give two cotranscripts of 5.2 and 4.6 kb in length: in the mutant, the 5.2-kb co-transcript was greatly lowered. NCA3 was isolated from a wild-type yeast genomic library by genetic complementation. The level of the 5.2-kb transcript, like the synthesis of subunits 6 and 8, was partly restored in the transformed strain. A 1011-nucleotide ORF was identified that encodes an hydrophilic protein of 35417 Da. Disruption of chromosomal DNA within the reading frame promoted a dramatic decrease of the 5.2-kb mRNA but did not abolish the respiratory competence of a wild-type strain. NCA3 is located on chromosome IV and produces a single 1780-b transcript.
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Affiliation(s)
- P Pélissier
- Institut de Biochimie et Génétique Cellulaires, Université de Bordeaux II, France
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33
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Camougrand N, Pélissier P, Velours G, Guérin M. NCA2, a second nuclear gene required for the control of mitochondrial synthesis of subunits 6 and 8 of ATP synthase in Saccharomyces cerevisiae. J Mol Biol 1995. [DOI: 10.1016/s0022-2836(05)80140-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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34
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Affiliation(s)
- R H Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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35
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[37] Whole-organism methods for inorganic sulfur oxidation by chemolithotrophs and photolithotrophs. Methods Enzymol 1994. [DOI: 10.1016/0076-6879(94)43039-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Beauvoit B, Rigoulet M, Bunoust O, Raffard G, Canioni P, Guérin B. Interactions between glucose metabolism and oxidative phosphorylations on respiratory-competent Saccharomyces cerevisiae cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 214:163-72. [PMID: 8508788 DOI: 10.1111/j.1432-1033.1993.tb17909.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The purpose of this work was to analyze the interactions between oxidative phosphorylations and glucose metabolism on yeast cells aerobically grown on lactate as carbon source and incubated in a resting cell medium. On such respiratory-competent yeast cells, four different metabolic steady states have particularly been studied: (a) glucose feeding under anaerobiosis, (b) ethanol supply under aerobiosis, (c) glucose supply under aerobiosis and (d) glucose plus ethanol under aerobiosis. For each condition, we measured: (a) the cellular ATP/ADP ratio and NADH content sustained under these conditions, (b) the glucose consumption rate (glucose conditions) and the respiratory rate (aerobic conditions). Under aerobic conditions, when ethanol is used as substrate, the ATP/ADP ratio and NADH level are very high as compared with glucose feeding. However, the rate of oxygen consumption is similar under both conditions. The main observation is a large increase in the respiratory rate when both glucose and ethanol are added. This increase corresponds to an ATP/ADP ratio and a NADH level lower than those observed with ethanol but higher than those with glucose. Therefore the response of the respiratory rate to the ATP/ADP ratio depends on the redox potential. We studied the way in which the ATP-consuming activity was increased under glucose+ethanol conditions. By NMR experiments, it appears that neither the futile cycle at the level of the phosphofructo-1-kinase/fructo-1,6-bisphosphatase couple nor the synthesis of carbohydrate stores could account for the increase in oxidative phosphorylation. However, it is shown that, in the presence of glucose+ethanol, ATP consumption is strongly stimulated. It is hypothesized that this consumption is essentially due to the combination of the well-known plasma membrane proton-ATPase activation by glucose and the high phosphate potential due to oxidative ethanol metabolism. While it is well documented that oxidative phosphorylations inhibit the glycolytic flux, i.e. the Pasteur effect, we clearly show in this work that the glycolytic pathway limits the ability of mitochondria to maintain a cellular phosphate potential.
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Affiliation(s)
- B Beauvoit
- Institut de Biochimie Cellulaire du CNRS, Université de Bordeaux II, France
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37
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Usta J, Griffiths DE. Dibutyltin-3-hydroxyflavone bromide: A fluorescent inhibitor of F1F0-ATPase. Appl Organomet Chem 1993. [DOI: 10.1002/aoc.590070306] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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38
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Guélin E, Chevallier J, Rigoulet M, Guérin B, Velours J. ATP synthase of yeast mitochondria. Isolation and disruption of the ATP epsilon gene. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)54128-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Usta J, Griffiths DE. Organotin-flavone complexes: a new class of fluorescent probes for F1F0ATPase. Biochem Biophys Res Commun 1992; 188:365-71. [PMID: 1417856 DOI: 10.1016/0006-291x(92)92394-d] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Fluorescent 5-coordinate organotin-flavone complexes of 3-hydroxy-flavone (Hof) and 3,5,7,2',4',-pentahydroxyflavone (morin) are good inhibitors of mitochondrial F1F0ATPase but do not inhibit F1-ATPase and they have been examined as possible fluorescent probes of F1F0ATPase. R2SnX (morin) complexes exhibit low fluorescence enhancement on binding to mitochondrial membranes with no displacement by equimolar tributyltin. In contrast R2SnX (of) complexes exhibit high fluorescence enhancement whose extent is variable and is displacable by equimolar tributyltin. Fluorescence enhancement by R2SnX (of) complexes correlates with the ATPase I50 values. Dialkyltin-3-hydroxy flavone, R2SnX(of), complexes act as a new class of fluorescent probes which titrate the F0 segment of F1F0ATPase.
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Affiliation(s)
- J Usta
- Department of Chemistry, University of Warwick, Coventry, UK
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Paul MF, Guerin B, Velours J. The C-terminal region of subunit 4 (subunit b) is essential for assembly of the F0 portion of yeast mitochondrial ATP synthase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 205:163-72. [PMID: 1532552 DOI: 10.1111/j.1432-1033.1992.tb16764.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The role of the C-terminal part of yeast ATP synthase subunit 4 (subunit b) in the assembly of the whole enzyme was studied by using nonsense mutants generated by site-directed mutagenesis. The removal of at least the last 10 amino-acid residues promoted mutants which were unable to grow with glycerol or lactate as carbon source. These mutants were devoid of subunit 4 and of another F0 subunit, the mitochondrially encoded subunit 6. The removal of the last eight amino-acid residues promoted a temperature-sensitive mutant (PVY161). At 37 degrees C this strain showed the same phenotype as above. When grown at permissive temperature (30 degrees C) with lactate as carbon source, PVY161 and the wild-type strain both displayed the same generation time and growth yield. Furthermore, the two strains showed identical cellular respiration rates at 30 degrees C and 37 degrees C. However, in vitro the ATP hydrolysis of PVY161 mitochondria exhibited a low sensitivity to F0 inhibitors, while ATP synthesis displayed the same oligomycin sensitivity as wild-type mitochondria. It is concluded that, in this mutant, the assembly of the truncated subunit 4 in PVY161 ATP synthase is thermosensitive and that, once a functional F0 is formed, it is stable. On the other hand, the removal of the last eight amino-acid residues promoted in vitro a proton leak between the site of action of oligomycin and F1.
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Affiliation(s)
- M F Paul
- Institut de Biochimie Cellulaire du Centre National de la Recherche Scientifique, Université de Bordeaux II, France
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Interaction of tributylin acetate and tributyltin chloride with dipalmitoyl phosphatidylcholine model membrane. Chem Phys Lipids 1991. [DOI: 10.1016/0009-3084(91)90113-p] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kodavanti PR, Cameron JA, Yallapragada PR, Vig PJ, Desaiah D. Inhibition of Ca2+ transport associated with cAMP-dependent protein phosphorylation in rat cardiac sarcoplasmic reticulum by triorganotins. Arch Toxicol 1991; 65:311-7. [PMID: 1659351 DOI: 10.1007/bf01968965] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Organotin compounds have been shown to interfere with cardiovascular system. We have studied the in vitro and in vivo effects of tributyltin bromide (TBT), triethyltin bromide (TET) and trimethyltin chloride (TMT) on the cardiac SR Ca2+ pump, as well as on protein phosphorylation of SR proteins, in order to understand the relative potency of these tin compounds. All the three tin compounds inhibited cardiac SR 45Ca uptake and Ca(2+)-ATPase in vitro in a concentration-dependent manner. The order of potency for Ca(2+)-ATPase as determined by IC50, is TBT (2 microM) greater than TET (63 microM) greater than TMT (280 microM). For 45Ca uptake, it followed the same order i.e., TBT (0.35 microM) greater than TET (10 microM) greater than TMT (440 microM). In agreement with the in vitro results, both SR Ca(2+)-ATPase and 45Ca uptake were significantly inhibited in rats treated with these tin compounds, indicating that these tin compounds inhibit cardiac SR Ca2+ transport. cAMP significantly elevated (70-80%) the 32P-binding to SR proteins in vitro in the absence of any organotin. In the presence of organotins, cAMP-stimulated 32P-binding to proteins was significantly reduced, but the decrease was concentration dependent only at lower concentrations. The order of potency is TBT greater than TET greater than TMT. In agreement with in vitro studies, cAMP-dependent 32P bound to proteins was significantly reduced in rats treated with TBT, TET and TMT. SDS-polyacrylamide gel electrophoresis of the cardiac SR revealed at least 30 Coomassie blue stainable bands ranging from 9 to 120 kDa.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P R Kodavanti
- Department of Neurology, University of Mississippi Medical Center, Jackson 39216
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Dupont CH, Rigoulet M, Beauvoit B, Guérin B. Mitochondrial modifications in a single nuclear mutant of Saccharomyces cerevisiae affected in cAMP-dependent protein phosphorylation. Curr Genet 1990; 17:507-13. [PMID: 2167772 DOI: 10.1007/bf00313079] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This paper reports studies of bioenergetic modifications in a TTR1 single-nuclear mutant, isolated as resistant to triethyltin, an inhibitor of mitochondrial ATPase, and effective in cAMP-dependent protein phosphorylation. This mutant appears to have lost the wild-type cell ability to respond to a decrease of oxygen concentration in the growth medium by a decrease of cytochrome concentration in the cell. ATP synthesis rate in mutant cells in both the prestationary and stationary phase of growth appeared increased in comparison to wild-type cells, as too was respiration rate. A comparative study of mitochondria extracted from wild-type and from TTR1 mutant cells showed an increase in respiration rate, an increase in ATP synthesis rate, and an increase in TPP+ uptake in mutant mitochondria. The specific ATPase activity, as well as its sensitivity to TET, appears to be similar for mitochondria extracted from both strains. It was proposed that the modification of mitochondrial biogenesis in the TTR1 mutant may be due to a response of the cell to an increase in ATP hydrolysis caused by the mutation. It is also possible that the modification in cAMP-dependent protein kinase regulation which appeared to occur in this mutant affects protein(s) involved in mitochondrial biogenesis.
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Affiliation(s)
- C H Dupont
- Institut de Biochimie Cellulaire et Neurochimie, CNRS, Bordeaux, France
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Dupont CH, Rigoulet M, Aigle M, Guérin B. Isolation and genetic study of triethyltin-resistant mutants of Saccharomyces cerevisiae. Curr Genet 1990; 17:465-72. [PMID: 2202522 DOI: 10.1007/bf00313073] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Three mutants of Saccharomyces cerevisiae resistant to triethyltin (an inhibitor of mitochondrial ATPase) on non-fermentative media, and non-resistant to this drug on fermentative media, were isolated and named TTR1, TTR2 and TTR3. Apart from triethyltin resistance, these mutants show the following common characteristics: (1) Increased intracellular cytochrome c concentration. (2) Increased respiration rate. (3) Decreased growth yield. (4) Increased growth sensitivity to several drugs inhibiting oxidative phosphorylation: namely, CCCP (permeabilizing inner mitochondrial membrane to protons), valinomycin (permeabilizing inner mitochondrial membrane to potassium) and oligomycin (inhibitor of mitochondrial ATPase). (5) Increased sensitivity to carbon source starvation. For each mutant, these characteristics appeared to be due to a single pleiotropic nuclear mutation. Mutation TTR1 causes additional phenotypic characteristics which do not appear in mutants TTR2 and TTR3: (1) Pinkish coloration of colonies which is more pronounced after a long growth period. (2) Inability of the cells to store glycogen. (3) Growth defect of the cells on a galactose-containing medium. (4) Inability of a diploid homozygote mutant strain to sporulate. All these phenotypic characteristics have already been described in yeast mutants deregulated in cAMP-dependent protein phosphorylation. Crossing of a strain bearing the TTR1 mutation with a strain mutated in the adenylate cyclase structural gene suggested that the TTR1 phenotype is due to a modification in regulation of cAPK by cAMP, making cell multiplication possible without intracellular cAMP.
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Affiliation(s)
- C H Dupont
- Institut de Biochimie Cellulaire et Neurochimie, CNRS, Bordeaux, France
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Harrison PG, Sharpe NW. Model studies of trialkyltin-protein interactions:13C NMR analysis of solution equilibria of the complex between trimethyltin and methylN-benzoyl-l-leucyl-l-histidinate. Appl Organomet Chem 1989. [DOI: 10.1002/aoc.590030205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Connerton IF, Griffiths DE. Organotin compounds as energy-potentiated uncouplers of rat liver mitochondria. Appl Organomet Chem 1989. [DOI: 10.1002/aoc.590030611] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Manon S, Rakotomanana F, Guérin M. In vivo and in vitro evidence for a proton leakage through the inner mitochondrial membrane in a mutant of Saccharomyces cerevisiae. EUROPEAN JOURNAL OF BIOCHEMISTRY 1988; 174:399-404. [PMID: 2838277 DOI: 10.1111/j.1432-1033.1988.tb14111.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Mutants of Saccharomyces cerevisiae were isolated which supported three mutations: two unlinked chromosomic mutations conferring thermosensitivity and cold sensitivity respectively, and a mitochondrial mutation conferring paromomycin sensitivity. When studied on isolated mitochondria, these mutants exhibited low phosphorylation efficiency and great proton permeability of their inner mitochondrial membrane. Experiments were carried out on whole cells: determination of growth rates, cellular yields and cellular respiration, either in the presence of triethyltin, an ATP synthase inhibitor, or in the presence of uncoupler, demonstrating that the proton leakage is actually a physiological phenomenon linked to the cold-sensitive phenotype. Experiments performed on isolated mitochondria confirmed the existence of such a proton leakage.
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Affiliation(s)
- S Manon
- Institut de Biochimie Cellulaire et Neurochimie du CNRS, Bordeaux, France
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50
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Griffiths DE, Connerton I. Effects of trialkyllead compounds on mitochondrial energy conservation. Appl Organomet Chem 1988. [DOI: 10.1002/aoc.590020212] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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