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Zarco-Zavala M, Mendoza-Hoffmann F, García-Trejo JJ. Unidirectional regulation of the F 1F O-ATP synthase nanomotor by the ζ pawl-ratchet inhibitor protein of Paracoccus denitrificans and related α-proteobacteria. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2018; 1859:762-774. [PMID: 29886048 DOI: 10.1016/j.bbabio.2018.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/28/2018] [Accepted: 06/05/2018] [Indexed: 12/20/2022]
Abstract
The ATP synthase is a reversible nanomotor that gyrates its central rotor clockwise (CW) to synthesize ATP and in counter clockwise (CCW) direction to hydrolyse it. In bacteria and mitochondria, two natural inhibitor proteins, namely the ε and IF1 subunits, prevent the wasteful CCW F1FO-ATPase activity by blocking γ rotation at the αDP/βDP/γ interface of the F1 portion. In Paracoccus denitrificans and related α-proteobacteria, we discovered a different natural F1-ATPase inhibitor named ζ. Here we revise the functional and structural data showing that this novel ζ subunit, although being different to ε and IF1, it also binds to the αDP/βDP/γ interface of the F1 of P. denitrificans. ζ shifts its N-terminal inhibitory domain from an intrinsically disordered protein region (IDPr) to an α-helix when inserted in the αDP/βDP/γ interface. We showed for the first time the key role of a natural ATP synthase inhibitor by the distinctive phenotype of a Δζ knockout mutant in P. denitrificans. ζ blocks exclusively the CCW F1FO-ATPase rotation without affecting the CW-F1FO-ATP synthase turnover, confirming that ζ is important for respiratory bacterial growth by working as a unidirectional pawl-ratchet PdF1FO-ATPase inhibitor, thus preventing the wasteful consumption of cellular ATP. In summary, ζ is a useful model that mimics mitochondrial IF1 but in α-proteobacteria. The structural, functional, and endosymbiotic evolutionary implications of this ζ inhibitor are discussed to shed light on the natural control mechanisms of the three natural inhibitor proteins (ε, ζ, and IF1) of this unique ATP synthase nanomotor, essential for life.
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Affiliation(s)
- Mariel Zarco-Zavala
- Departamento de Biología, Facultad de Química, Ciudad Universitaria, Universidad Nacional Autónoma de México (U.N.A.M.), Delegación Coyoacán, Ciudad de México (CDMX), CP 04510, Mexico; Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Francisco Mendoza-Hoffmann
- Departamento de Biología, Facultad de Química, Ciudad Universitaria, Universidad Nacional Autónoma de México (U.N.A.M.), Delegación Coyoacán, Ciudad de México (CDMX), CP 04510, Mexico
| | - José J García-Trejo
- Departamento de Biología, Facultad de Química, Ciudad Universitaria, Universidad Nacional Autónoma de México (U.N.A.M.), Delegación Coyoacán, Ciudad de México (CDMX), CP 04510, Mexico.
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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: 14] [Impact Index Per Article: 2.3] [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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New insight in a new entity: the mitochondrial permeability transition pore arises from the Ca 2+-activated F 1F O-ATPases. Sci Bull (Beijing) 2018; 63:143-145. [PMID: 36658996 DOI: 10.1016/j.scib.2017.12.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Mendoza-Hoffmann F, Pérez-Oseguera Á, Cevallos MÁ, Zarco-Zavala M, Ortega R, Peña-Segura C, Espinoza-Simón E, Uribe-Carvajal S, García-Trejo JJ. The Biological Role of the ζ Subunit as Unidirectional Inhibitor of the F 1F O-ATPase of Paracoccus denitrificans. Cell Rep 2018; 22:1067-1078. [PMID: 29386127 DOI: 10.1016/j.celrep.2017.12.106] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 09/09/2017] [Accepted: 12/28/2017] [Indexed: 11/16/2022] Open
Abstract
The biological roles of the three natural F1FO-ATPase inhibitors, ε, ζ, and IF1, on cell physiology remain controversial. The ζ subunit is a useful model for deletion studies since it mimics mitochondrial IF1, but in the F1FO-ATPase of Paracoccus denitrificans (PdF1FO), it is a monogenic and supernumerary subunit. Here, we constructed a P. denitrificans 1222 derivative (PdΔζ) with a deleted ζ gene to determine its role in cell growth and bioenergetics. The results show that the lack of ζ in vivo strongly restricts respiratory P. denitrificans growth, and this is restored by complementation in trans with an exogenous ζ gene. Removal of ζ increased the coupled PdF1FO-ATPase activity without affecting the PdF1FO-ATP synthase turnover, and the latter was not affected at all by ζ reconstitution in vitro. Therefore, ζ works as a unidirectional pawl-ratchet inhibitor of the PdF1FO-ATPase nanomotor favoring the ATP synthase turnover to improve respiratory cell growth and bioenergetics.
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Affiliation(s)
- Francisco Mendoza-Hoffmann
- Departamento de Biología, Facultad de Química, Ciudad Universitaria, Universidad Nacional Autónoma de México (U.N.A.M.), Delegación Coyoacán, Ciudad de México (CDMX) 04510, México
| | - Ángeles Pérez-Oseguera
- Programa de Genómica Evolutiva, Centro de Ciencias Genómicas, U.N.A.M., Cuernavaca, Morelos, México
| | - Miguel Ángel Cevallos
- Programa de Genómica Evolutiva, Centro de Ciencias Genómicas, U.N.A.M., Cuernavaca, Morelos, México
| | | | - Raquel Ortega
- Departamento de Biología, Facultad de Química, Ciudad Universitaria, Universidad Nacional Autónoma de México (U.N.A.M.), Delegación Coyoacán, Ciudad de México (CDMX) 04510, México
| | | | | | | | - José J García-Trejo
- Departamento de Biología, Facultad de Química, Ciudad Universitaria, Universidad Nacional Autónoma de México (U.N.A.M.), Delegación Coyoacán, Ciudad de México (CDMX) 04510, México.
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García-Trejo JJ, Zarco-Zavala M, Mendoza-Hoffmann F, Hernández-Luna E, Ortega R, Mendoza-Hernández G. The Inhibitory Mechanism of the ζ Subunit of the F1FO-ATPase Nanomotor of Paracoccus denitrificans and Related α-Proteobacteria. J Biol Chem 2016; 291:538-46. [PMID: 26546676 PMCID: PMC4705375 DOI: 10.1074/jbc.m115.688143] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 11/02/2015] [Indexed: 01/08/2023] Open
Abstract
The ζ subunit is a novel inhibitor of the F1FO-ATPase of Paracoccus denitrificans and related α-proteobacteria. It is different from the bacterial (ϵ) and mitochondrial (IF1) inhibitors. The N terminus of ζ blocks rotation of the γ subunit of the F1-ATPase of P. denitrificans (Zarco-Zavala, M., Morales-Ríos, E., Mendoza-Hernández, G., Ramírez-Silva, L., Pérez-Hernández, G., and García-Trejo, J. J. (2014) FASEB J. 24, 599-608) by a hitherto unknown quaternary structure that was first modeled here by structural homology and protein docking. The F1-ATPase and F1-ζ models of P. denitrificans were supported by cross-linking, limited proteolysis, mass spectrometry, and functional data. The final models show that ζ enters into F1-ATPase at the open catalytic αE/βE interface, and two partial γ rotations lock the N terminus of ζ in an "inhibition-general core region," blocking further γ rotation, while the ζ globular domain anchors it to the closed αDP/βDP interface. Heterologous inhibition of the F1-ATPase of P. denitrificans by the mitochondrial IF1 supported both the modeled ζ binding site at the αDP/βDP/γ interface and the endosymbiotic α-proteobacterial origin of mitochondria. In summary, the ζ subunit blocks the intrinsic rotation of the nanomotor by inserting its N-terminal inhibitory domain at the same rotor/stator interface where the mitochondrial IF1 or the bacterial ϵ binds. The proposed pawl mechanism is coupled to the rotation of the central γ subunit working as a ratchet but with structural differences that make it a unique control mechanism of the nanomotor to favor the ATP synthase activity over the ATPase turnover in the α-proteobacteria.
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Affiliation(s)
| | | | | | | | - Raquel Ortega
- From the Departamento de Biología, Facultad de Química, and
| | - Guillermo Mendoza-Hernández
- the Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Delegación Coyoacán, D.F., CP 04510, México
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Coello P, Martínez-Barajas E. SnRK1 is differentially regulated in the cotyledon and embryo axe of bean (Phaseolus vulgaris L) seeds. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 80:153-9. [PMID: 24762788 DOI: 10.1016/j.plaphy.2014.03.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 03/30/2014] [Indexed: 05/25/2023]
Abstract
SnRK1 activity is developmentally regulated in bean seeds and exhibits a transient increase with the highest value at 20 days after anthesis (DAA), which coincides with the beginning of protein and starch accumulation. The catalytic subunit of SnRK1 shows a consistent decrease throughout the seed development period. However, by 15 DAA a significant proportion of the catalytic subunit appears phosphorylated. The increase in activity and phosphorylation of the catalytic subunit coincides with a decrease in hexoses. However, SnRK1 activity is differentially regulated in the cotyledon and embryo axe, where a larger proportion of the catalytic subunit is phosphorylated. SnRK1 obtained from endosperm extract is inhibited by T6P and to a lesser extent by ADPG and UDPG, whereas the enzyme isolated from embryo is virtually insensitive to T6P but exhibits some inhibition by ADPG and UDPG. In cotyledon extracts, the effects of T6P and ADPG on SnRK1 activity are additive, whereas in embryo extract, T6P inhibits the enzyme only when ADPG is present. After fractionation on Sephacryl-S300, SnRK1 activity obtained from cotyledon extracts is detected as a single peak associated with a molecular weight of 250 kDa whereas that obtained form embryo axe extracts detected as 2 peaks associated with molecular weight of 250 and 180 kDa. In both cases, the catalytic subunit exhibits a wide distribution but is concentrated in the fractions with the highest activity. To analyse the composition of the complex, cotyledon and embryo extracts were treated with a reversible crosslinker (DSP). DSP induced the formation of complexes with molecular weights of 97 and 180 kDa in the cotyledon and embryo extracts, respectively. Since all the phosphorylated catalytic subunit is present in the complexes induced by DSP, it appears that the phosphorylation favors its interaction with other proteins.
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Affiliation(s)
- Patricia Coello
- Departamento de Bioquímica, Facultad de Química-UNAM, México 04510, D.F, Mexico
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Zarco-Zavala M, Morales-Ríos E, Mendoza-Hernández G, Ramírez-Silva L, Pérez-Hernández G, García-Trejo JJ. The ζ subunit of the F1FO-ATP synthase of α-proteobacteria controls rotation of the nanomotor with a different structure. FASEB J 2014; 28:2146-57. [PMID: 24522203 DOI: 10.1096/fj.13-241430] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The ζ subunit is a novel natural inhibitor of the α-proteobacterial F1FO-ATPase described originally in Paracoccus denitrificans. To characterize the mechanism by which this subunit inhibits the F1FO nanomotor, the ζ subunit of Paracoccus denitrificans (Pd-ζ) was analyzed by the combination of kinetic, biochemical, bioinformatic, proteomic, and structural approaches. The ζ subunit causes full inhibition of the sulfite-activated PdF1-ATPase with an apparent IC50 of 270 nM by a mechanism independent of the ε subunit. The inhibitory region of the ζ subunit resides in the first 14 N-terminal residues of the protein, which protrude from the 4-α-helix bundle structure of the isolated ζ subunit, as resolved by NMR. Cross-linking experiments show that the ζ subunit interacts with rotor (γ) and stator (α, β) subunits of the F1-ATPase, indicating that the ζ subunit hinders rotation of the central stalk. In addition, a putatively regulatory nucleotide-binding site was found in the ζ subunit by isothermal titration calorimetry. Together, the data show that the ζ subunit controls the rotation of F1FO-ATPase by a mechanism reminiscent of, but different from, those described for mitochondrial IF1 and bacterial ε subunits where the 4-α-helix bundle of ζ seems to work as an anchoring domain that orients the N-terminal inhibitory domain to hinder rotation of the central stalk.
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Affiliation(s)
- Mariel Zarco-Zavala
- 1Universidad Nacional Autónoma de México (UNAM), Facultad de Química, Departamento de Biología, Circuito Escolar, s/n, Laboratorio 206, Edificio F, Ciudad Universitaria, Coyoacán, CP 04510, México, DF.
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8
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Zarco-Zavala M, Morales-Ríos E, Serrano-Navarro P, Wüthrich K, Mendoza-Hernández G, Ramírez-Silva L, García-Trejo J. Corrigendum to “The ζ subunit of the α-proteobacterial F1FO-ATP synthase in Paracoccus denitrificans: A novel control mechanism of the central rotor” [Biochim. Biophys. Acta 1817S (2012) S27–S28]. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013. [DOI: 10.1016/j.bbabio.2012.09.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Morales-Ríos E, de la Rosa-Morales F, Mendoza-Hernández G, Rodríguez-Zavala JS, Celis H, Zarco-Zavala M, García-Trejo JJ. A novel 11-kDa inhibitory subunit in the F1FO ATP synthase of Paracoccus denitrificans and related alpha-proteobacteria. FASEB J 2009; 24:599-608. [PMID: 19783785 DOI: 10.1096/fj.09-137356] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The F(1)F(O) and F(1)-ATPase complexes of Paracoccus denitrificans were isolated for the first time by ion exchange, gel filtration, and density gradient centrifugation into functional native preparations. The liposome-reconstituted holoenzyme preserves its tight coupling between F(1) and F(O) sectors, as evidenced by its high sensitivity to the F(O) inhibitors venturicidin and diciclohexylcarbodiimide. Comparison and N-terminal sequencing of the band profile in SDS-PAGE of the F(1) and F(1)F(O) preparations showed a novel 11-kDa protein in addition to the 5 canonical alpha, beta, gamma, delta, and epsilon subunits present in all known F(1)-ATPase complexes. BN-PAGE followed by 2D-SDS-PAGE confirmed the presence of this 11-kDa protein bound to the native F(1)F(O)-ATP synthase of P. denitrificans, as it was observed after being isolated. The recombinant 11 kDa and epsilon subunits of P. denitrificans were cloned, overexpressed, isolated, and reconstituted in particulate F(1)F(O) and soluble F(1)-ATPase complexes. The 11-kDa protein, but not the epsilon subunit, inhibited the F(1)F(O) and F(1)-ATPase activities of P. denitrificans. The 11-kDa protein was also found in Rhodobacter sphaeroides associated to its native F(1)F(O)-ATPase. Taken together, the data unveil a novel inhibitory mechanism exerted by this 11-kDa protein on the F(1)F(O)-ATPase nanomotor of P. denitrificans and closely related alpha-proteobacteria.
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Affiliation(s)
- Edgar Morales-Ríos
- Biology Department, Chemistry Faculty, National Autonomous University of Mexico (UNAM), Mexico City, Mexico
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Shen L, Zhi L, Hu W, Wu MX. IEX-1 targets mitochondrial F1Fo-ATPase inhibitor for degradation. Cell Death Differ 2009; 16:603-12. [PMID: 19096392 PMCID: PMC2696391 DOI: 10.1038/cdd.2008.184] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
IEX-1 (Immediate Early response gene X-1) is a stress-inducible gene. It suppresses production of reactive oxygen species (ROS) and protects cells from apoptosis induced by a wide range of stimuli, but the underlying mechanism is not known. This study reveals that IEX-1 targets the mitochondrial F1Fo-ATPase Inhibitor (IF1) for degradation, resulting in acceleration of ATP hydrolysis, concomitant with reduction in ROS production. A prominent role for IF1 degradation in the function of IEX-1 was corroborated by siRNA-mediated gene silencing of IF1 that recapitulated the effects of IEX-1 on ATP hydrolysis and ROS production. Moreover, progressive C-terminal truncation studies demonstrated that IEX-1 interacted with the C terminus of IF1 and the interaction might render IF1 prone to degradation by an as yet unidentified mitochondrial protease. In support of a physiological importance of IEX-1 in the modulation of IF1 expression, gene-targeted deletion of IEX-1 stabilized IF1 and reduced mitochondrial F1Fo-ATPase activity in vivo. The altered activity of the F1Fo enzyme may account for a metabolic switch from oxidative phosphorylation toward glycolysis in IEX-1 deficient cells. Thus, IEX-1 deficient cells were more susceptible to glucose deprivation than wild type counterparts and displayed increased glucose uptake and lactate production in hypoxic conditions. The cells were also relatively refractory to oligomycin-mediated inhibition of ATP production. The studies offer novel insights into the primary role of IEX-1 in regulating a balance between energy provision and ROS production.
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Affiliation(s)
- L Shen
- Wellman Center of Photomedicine, Massachusetts General Hospital, and Department of Dermatology, Harvard Medical School, Boston, MA 02114, USA
| | - L Zhi
- Wellman Center of Photomedicine, Massachusetts General Hospital, and Department of Dermatology, Harvard Medical School, Boston, MA 02114, USA
| | - W Hu
- Wellman Center of Photomedicine, Massachusetts General Hospital, and Department of Dermatology, Harvard Medical School, Boston, MA 02114, USA
| | - MX Wu
- Wellman Center of Photomedicine, Massachusetts General Hospital, and Department of Dermatology, Harvard Medical School, Boston, MA 02114, USA
- Harvard-MIT Division of Health Sciences and Technology, Boston, MA 02115, USA
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Grover GJ, Malm J. Pharmacological profile of the selective mitochondrial F1F0 ATP hydrolase inhibitor BMS-199264 in myocardial ischemia. Cardiovasc Ther 2009; 26:287-96. [PMID: 19035880 DOI: 10.1111/j.1755-5922.2008.00065.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The mitochondrial F1F0 ATP synthase is responsible for the majority of ATP production in mammals and does this through a rotary catalytic mechanism. Studies show that the F1F0 ATP synthase can switch to an ATP hydrolase, and this occurs under conditions seen during myocardial ischemia. This ATP hydrolysis causes wasting of ATP that does not produce work. The degree of ATP inefficiently hydrolyzed during ischemia may be as high as 50-90% of the total. A naturally occurring, reversible inhibitor (IF-1) of the hydrolase activity is in the mitochondria, and it has a pH optimum of 6.8. Based on studies with the nonselective (inhibit both synthase and hydrolase activity) inhibitors aurovertin B and oligomycin B reduce the rate of ATP depletion during ischemia, showing that IF-1 does not completely block hydrolase activity. Oligomycin and aurovertin cannot be used for treating myocardial ischemia as they will reduce ATP production in healthy tissue. We generated a focused structure-activity relationship, and several compounds were identified that selectively inhibited the F1F0 ATP hydrolase activity while having no effect on synthase function. One compound, BMS-199264 had no effect on F1F0 ATP synthase function in submitochondrial particles while inhibiting hydrolase function, unlike oligomycin that inhibits both. BMS-199264 selectively inhibited ATP decline during ischemia while not affecting ATP production in normoxic and reperfused hearts. BMS-191264 also reduced cardiac necrosis and enhanced the recovery of contractile function following reperfusion. These data also suggest that the reversal of the synthase and hydrolase activities is not merely a chemical reaction run in reverse.
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Affiliation(s)
- Gary J Grover
- Department of Pharmacology, Eurofins-PSL, Dayton, NJ 08810, USA.
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12
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Hong S, Pedersen PL. ATP synthase and the actions of inhibitors utilized to study its roles in human health, disease, and other scientific areas. Microbiol Mol Biol Rev 2008; 72:590-641, Table of Contents. [PMID: 19052322 PMCID: PMC2593570 DOI: 10.1128/mmbr.00016-08] [Citation(s) in RCA: 236] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
ATP synthase, a double-motor enzyme, plays various roles in the cell, participating not only in ATP synthesis but in ATP hydrolysis-dependent processes and in the regulation of a proton gradient across some membrane-dependent systems. Recent studies of ATP synthase as a potential molecular target for the treatment of some human diseases have displayed promising results, and this enzyme is now emerging as an attractive molecular target for the development of new therapies for a variety of diseases. Significantly, ATP synthase, because of its complex structure, is inhibited by a number of different inhibitors and provides diverse possibilities in the development of new ATP synthase-directed agents. In this review, we classify over 250 natural and synthetic inhibitors of ATP synthase reported to date and present their inhibitory sites and their known or proposed modes of action. The rich source of ATP synthase inhibitors and their known or purported sites of action presented in this review should provide valuable insights into their applications as potential scaffolds for new therapeutics for human and animal diseases as well as for the discovery of new pesticides and herbicides to help protect the world's food supply. Finally, as ATP synthase is now known to consist of two unique nanomotors involved in making ATP from ADP and P(i), the information provided in this review may greatly assist those investigators entering the emerging field of nanotechnology.
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Affiliation(s)
- Sangjin Hong
- Department of Biological Chemistry, Johns Hopkins University, School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205-2185, USA
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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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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: 79] [Impact Index Per Article: 4.9] [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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15
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Huang LJ, Hsu C, Tsai TN, Wang SJ, Yang RC. Suppression of mitochondrial ATPase inhibitor protein (IF1) in the liver of late septic rats. BIOCHIMICA ET BIOPHYSICA ACTA 2007; 1767:888-96. [PMID: 17490602 DOI: 10.1016/j.bbabio.2007.03.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Revised: 03/21/2007] [Accepted: 03/27/2007] [Indexed: 11/19/2022]
Abstract
Sepsis and ensuing multiple organ failure continue to be the most leading cause of death in critically ill patients. Despite hepatocyte-related dysfunctions such as necrosis, apoptosis as well as mitochondrial damage are observed in the process of sepsis, the molecular mechanism of pathogenesis remains uncertain. We recently identified one of the differentially expressed genes, mitochondrial ATPase inhibitor protein (IF1) which is down-regulated in late septic liver. Hence, we further hypothesized that the variation of IF1 protein may be one of the causal events of the hepatic dysfunction during late sepsis. The results showed that the elevated mitochondrial F0F1-ATPase activity is concomitant with the decline of intramitochondrial ATP concentration in late septic liver. In addition, the key finding of this study showed that the mRNA and the mitochondrial content of IF1 were decreased in late sepsis while no detectable IF1 was found in cytoplasm. When analyzed by immunoprecipitation, it seems reasonable to imply that the association capability of IF1 with F1-ATPase beta-subunit is not affected. These results confirm the first evidence showing that the suppression of IF1 expression and subsequent elevated mitochondrial F0F1-ATPase activity might contribute to the bioenergetic failure in the liver during late sepsis.
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Affiliation(s)
- Li-Ju Huang
- Department of Physiology, Graduate Institute of Medicine, Kaohsiung Medical University, and Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
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16
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García JJ, Morales-Ríos E, Cortés-Hernandez P, Rodríguez-Zavala JS. The inhibitor protein (IF1) promotes dimerization of the mitochondrial F1F0-ATP synthase. Biochemistry 2006; 45:12695-703. [PMID: 17042487 DOI: 10.1021/bi060339j] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The effect of increased expression or reconstitution of the mitochondrial inhibitor protein (IF1) on the dimer/monomer ratio (D/M) of the rat liver and bovine heart F1F0-ATP synthase was studied. The 2-fold increased expression of IF1 in AS-30D hepatoma mitochondria correlated with a 1.4-fold increase in the D/M ratio of the ATP synthase extracted with digitonin as determined by blue native electrophoresis and averaged densitometry analyses. Removal of IF1 from rat liver or bovine heart submitochondrial particles increased the F1F0-ATPase activity and decreased the D/M ratio of the ATP synthase. Reconstitution of recombinant IF1 into submitochondrial particles devoid of IF1 inhibited the F1F0-ATPase activity by 90% and restored partially the D/M ratio of the whole F1F0 complex as revealed by blue native electrophoresis and subsequent SDS-PAGE or glycerol density gradient centrifugation. Thus, the inhibitor protein promotes or stabilizes the dimeric form of the intact F1F0-ATP synthase. A possible location of the IF1 protein in the dimeric structure of the rat liver F1F0 complex is proposed. According to crystallographic and electron microscopy analyses, dimeric IF1 could bridge the F1-F1 part of the dimeric F1F0-ATP synthase in the inner mitochondrial membrane.
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Affiliation(s)
- José J García
- Departamento de Bioquímica and Cardiovascular Disease's Genomic and Proteomic Study Group, Instituto Nacional de Cardiología Ignacio Chavez, Juan Badiano 1, Col. Sección XVI, México, DF, Mexico 14080.
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17
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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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18
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de Gómez-Puyou MT, Domínguez-Ramírez L, Pérez-Hernández G, Gómez-Puyou A. Effect of denaturants on multisite and unisite ATP hydrolysis by bovine heart submitochondrial particles with and without inhibitor protein. Arch Biochem Biophys 2005; 439:129-37. [PMID: 15950171 DOI: 10.1016/j.abb.2005.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Revised: 05/03/2005] [Accepted: 05/05/2005] [Indexed: 11/26/2022]
Abstract
The effect of guanidinium hydrochloride (GdnHCl) on multisite and unisite ATPase activity by F0F1 of submitochondrial particles from bovine hearts was studied. In particles without control by the inhibitor protein, 50 mM GdnHCl inhibited multisite hydrolysis by about 85%; full inhibition required around 500 mM. In the range of 500-650 mM, GdnHCl enhanced the rate of unisite catalysis by promoting product release; it also increased the rate of hydrolysis of ATP bound to the catalytic site without GdnHCl. GdnHCl diminished the affinity of the enzyme for aurovertin. The effects of GdnHCl were irreversible. The results suggest that disruption of intersubunit contacts in F0F1 abolishes multisite hydrolysis and stimulates of unisite hydrolysis. Particles under control by the inhibitor protein were insensitive to concentrations of GdnHCl that induce the aforementioned alterations of F0F1 free of inhibitor protein, indicating that the protein stabilizes the global structure of particulate F1.
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Affiliation(s)
- Marietta Tuena de Gómez-Puyou
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70243, 04510 México, D. F., Mexico.
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19
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Cortés-Hernández P, Domínguez-Ramírez L, Estrada-Bernal A, Montes-Sánchez DG, Zentella-Dehesa A, de Gómez-Puyou MT, Gómez-Puyou A, García JJ. The inhibitor protein of the F1F0-ATP synthase is associated to the external surface of endothelial cells. Biochem Biophys Res Commun 2005; 330:844-9. [PMID: 15809073 DOI: 10.1016/j.bbrc.2005.03.064] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2005] [Indexed: 11/22/2022]
Abstract
The ATPase inhibitor protein (IP) of mitochondria was detected in the plasma membrane of living endothelial cells by flow cytometry, competition assays, and confocal microscopy of cells exposed to IP antibodies. The plasma membranes of endothelial cells also possess beta-subunits of the mitochondrial ATPase. Plasma membranes have the capacity to bind exogenous IP. TNF-alpha decreases the level of beta-subunits and increases the amount of IP, indicating that the ratio of IP to beta-subunit exhibits significant variations. Therefore, it is probable that the function of IP in the plasma membrane of endothelial cells is not limited to regulation of catalysis.
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20
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Kidd T, Abu-Shumays R, Katzen A, Sisson JC, Jiménez G, Pinchin S, Sullivan W, Ish-Horowicz D. The epsilon-subunit of mitochondrial ATP synthase is required for normal spindle orientation during the Drosophila embryonic divisions. Genetics 2005; 170:697-708. [PMID: 15834145 PMCID: PMC1450411 DOI: 10.1534/genetics.104.037648] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We describe the maternal-effect and zygotic phenotypes of null mutations in the Drosophila gene for the epsilon-subunit of mitochondrial ATP synthase, stunted (sun). Loss of zygotic sun expression leads to a dramatic delay in the growth rate of first instar larvae and ultimately death. Embryos lacking maternally supplied sun (sun embryos) have a sixfold reduction in ATP synthase activity. Cellular analysis of sun embryos shows defects only after the nuclei have migrated to the cortex. During the cortical divisions the actin-based metaphase and cellularization furrows do not form properly, and the nuclei show abnormal spacing and division failures. The most striking abnormality is that nuclei and spindles form lines and clusters, instead of adopting a regular spacing. This is reflected in a failure to properly position neighboring nonsister centrosomes during the telophase-to-interphase transition of the cortical divisions. Our study is consistent with a role for Sun in mitochondrial ATP synthesis and suggests that reduced ATP levels selectively affect molecular motors. As Sun has been identified as the ligand for the Methuselah receptor that regulates aging, Sun may function both within and outside mitochondria.
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Affiliation(s)
- Thomas Kidd
- Developmental Genetics Laboratory, Cancer Research UK, London, England.
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21
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Corvest V, Sigalat C, Venard R, Falson P, Mueller DM, Haraux F. The binding mechanism of the yeast F1-ATPase inhibitory peptide: role of catalytic intermediates and enzyme turnover. J Biol Chem 2005; 280:9927-36. [PMID: 15640141 DOI: 10.1074/jbc.m414098200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mechanism of inhibition of yeast mitochondrial F(1)-ATPase by its natural regulatory peptide, IF1, was investigated by correlating the rate of inhibition by IF1 with the nucleotide occupancy of the catalytic sites. Nucleotide occupancy of the catalytic sites was probed by fluorescence quenching of a tryptophan, which was engineered in the catalytic site (beta-Y345W). Fluorescence quenching of a beta-Trp(345) indicates that the binding of MgADP to F(1) can be described as 3 binding sites with dissociation constants of K(d)(1) = 10 +/- 2 nm, K(d2) = 0.22 +/- 0.03 microm, and K(d3) = 16.3 +/- 0.2 microm. In addition, the ATPase activity of the beta-Trp(345) enzyme followed simple Michaelis-Menten kinetics with a corresponding K(m) of 55 microm. Values for the K(d) for MgATP were estimated and indicate that the K(m) (55 microm) for ATP hydrolysis corresponds to filling the third catalytic site on F(1). IF1 binds very slowly to F(1)-ATPase depleted of nucleotides and under unisite conditions. The rate of inhibition by IF1 increased with increasing concentration of MgATP to about 50 mum, but decreased thereafter. The rate of inhibition was half-maximal at 5 microm MgATP, which is 10-fold lower than the K(m) for ATPase. The variations of the rate of IF1 binding are related to changes in the conformation of the IF1 binding site during the catalytic reaction cycle of ATP hydrolysis. A model is proposed that suggests that IF1 binds rapidly, but loosely to F(1) with two or three catalytic sites filled, and is then locked in the enzyme during catalytic hydrolysis of ATP.
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Affiliation(s)
- Vincent Corvest
- Service de Bioénergétique, Département de Biologie Joliot-Curie and CNRS-URA 2096, CEA Saclay, F 91191 Gif-sur-Yvette, France
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22
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Bravo C, Minauro-Sanmiguel F, Morales-Ríos E, Rodríguez-Zavala JS, García JJ. Overexpression of the inhibitor protein IF(1) in AS-30D hepatoma produces a higher association with mitochondrial F(1)F(0) ATP synthase compared to normal rat liver: functional and cross-linking studies. J Bioenerg Biomembr 2005; 36:257-64. [PMID: 15337856 DOI: 10.1023/b:jobb.0000031977.99479.ea] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
According to functional studies, the higher IF(1) content reported in mitochondria of cancerous cells is supposed to induce a higher association with the F(1)F(0) complex than in normal cells and therefore a better inhibition of its ATPase activity. The first structural evidence supporting this prediction is here presented. Densitometric analyses of Western blotting experiments indicated a 2-fold increase in IF(1) content of AS-30D submitochondrial particles compared to normal rat liver controls. The ratio of IF(1)/F(1) alpha subunit increased similarly as judged by Westernblot analyses. This IF(1) overexpression correlated with a slower rate of IF(1) release (F(1)F(0)-ATPase activation) from the F(1)F(0) complex in AS-30D than in normal rat liver submitochondrial particles. The IF(1)-IF(1), gamma-IF(1), and alpha-IF(1) cross-linkages previously formed with dithiobis(succinimidylpropionate) in bovine F(1)F(0)I and IF(1) complexes were reproduced in the F(1)F(0)I-ATP synthase of hepatoma AS-30D cells. However, a much lower yield of IF(1) cross-linkages was found in normal rat liver particles which made them almost undetectable in SMP as well as in the immunoprecipitated F(1)F(0)I complex. Modeling in vivo IF(1) overexpression of cancerous cells by in vitro reconstitution of excess recombinant IF(1) with rat liver submitochondrial particles devoid of IF(1) reproduced the same IF(1) cross-linkages observed in AS-30D particles.
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Affiliation(s)
- Concepción Bravo
- Departamento de Bioquímica, Instituto Nacional de Cardiología, "Ignacio Chávez," México, México
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23
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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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24
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Galkin M, Venard R, Vaillier J, Velours J, Haraux F. Functional transitions of F0F1-ATPase mediated by the inhibitory peptide IF1 in yeast coupled submitochondrial particles. EUROPEAN JOURNAL OF BIOCHEMISTRY 2004; 271:1963-70. [PMID: 15128305 DOI: 10.1111/j.1432-1033.2004.04108.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mechanism of inhibition of yeast F(0)F(1)-ATPase by its naturally occurring protein inhibitor (IF1) was investigated in submitochondrial particles by studying the IF1-mediated ATPase inhibition in the presence and absence of a protonmotive force. In the presence of protonmotive force, IF1 added during net NTP hydrolysis almost completely inhibited NTPase activity. At moderate IF1 concentration, subsequent uncoupler addition unexpectedly caused a burst of NTP hydrolysis. We propose that the protonmotive force induces the conversion of IF1-inhibited F(0)F(1)-ATPase into a new form having a lower affinity for IF1. This form remains inactive for ATP hydrolysis after IF1 release. Uncoupling simultaneously releases ATP hydrolysis and converts the latent form of IF1-free F(0)F(1)-ATPase back to the active form. The relationship between the different steps of the catalytic cycle, the mechanism of inhibition by IF1 and the interconversion process is discussed.
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Affiliation(s)
- Mikhail Galkin
- Service de Bioénergétique & CNRS-URA 2096, Gif-sur-Yvette, France
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