1401
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Nurbaeva MK, Schmid E, Szteyn K, Yang W, Viollet B, Shumilina E, Lang F. Enhanced Ca²⁺ entry and Na+/Ca²⁺ exchanger activity in dendritic cells from AMP-activated protein kinase-deficient mice. FASEB J 2012; 26:3049-58. [PMID: 22474243 DOI: 10.1096/fj.12-204024] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In dendritic cells (DCs), chemotactic chemokines, such as CXCL12, rapidly increase cytosolic Ca(2+)concentrations ([Ca(2+)](i)) by triggering Ca(2+) release from intracellular stores followed by store-operated Ca(2+) (SOC) entry. Increase of [Ca(2+)](i) is blunted and terminated by Ca(2+) extrusion, accomplished by K(+)-independent Na(+)/Ca(2+) exchangers (NCXs) and K(+)-dependent Na(+)/Ca(2+) exchangers (NCKXs). Increased [Ca(2+)](i) activates energy-sensing AMP-activated protein kinase (AMPK), which suppresses proinflammatory responses of DCs and macrophages. The present study explored whether AMPK participates in the regulation of DC [Ca(2+)](i) and migration. DCs were isolated from AMPKα1-deficient (ampk(-/-)) mice and, as control, from their wild-type (ampk(+/+)) littermates. AMPKα1, Orai1-2, STIM1-2, and mitochondrial calcium uniporter protein expression was determined by Western blotting, [Ca(2+)](i) by Fura-2 fluorescence, SOC entry by inhibition of endosomal Ca(2+) ATPase with thapsigargin (1 μM), Na(+)/Ca(2+) exchanger activity from increase of [Ca(2+)](i), and respective whole-cell current in patch clamp following removal of extracellular Na(+). Migration was quantified utilizing transwell chambers. AMPKα1 protein is expressed in ampk(+/+) DCs but not in ampk(-/-) DCs. CXCL12 (300 ng/ml)-induced increase of [Ca(2+)](i), SOC entry, Orai 1 protein abundance, NCX, and NCKX were all significantly higher in ampk(-/-) DCs than in ampk(+/+) DCs. NCX and NCKX currents were similarly increased in ampk(-/-) DCs. Moreover, CXCL12 (50 ng/ml)-induced DC migration was enhanced in ampk(-/-) DCs. AMPK thus inhibits SOC entry, Na(+)/Ca(2+) exchangers, and migration of DCs.
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1402
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Zampese E, Pizzo P. Intracellular organelles in the saga of Ca2+ homeostasis: different molecules for different purposes? Cell Mol Life Sci 2012; 69:1077-104. [PMID: 21968921 PMCID: PMC11114864 DOI: 10.1007/s00018-011-0845-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 09/15/2011] [Accepted: 09/19/2011] [Indexed: 11/28/2022]
Abstract
An increase in the concentration of cytosolic free Ca(2+) is a key component regulating different cellular processes ranging from egg fertilization, active secretion and movement, to cell differentiation and death. The multitude of phenomena modulated by Ca(2+), however, do not simply rely on increases/decreases in its concentration, but also on specific timing, shape and sub-cellular localization of its signals that, combined together, provide a huge versatility in Ca(2+) signaling. Intracellular organelles and their Ca(2+) handling machineries exert key roles in this complex and precise mechanism, and this review will try to depict a map of Ca(2+) routes inside cells, highlighting the uniqueness of the different Ca(2+) toolkit components and the complexity of the interactions between them.
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Affiliation(s)
- Enrico Zampese
- Department of Biomedical Sciences, University of Padova, Viale G. Colombo 3, 35121 Padova, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, Viale G. Colombo 3, 35121 Padova, Italy
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1403
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Mitochondrial Ca(2+) signals in autophagy. Cell Calcium 2012; 52:44-51. [PMID: 22459281 DOI: 10.1016/j.ceca.2012.03.001] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 02/29/2012] [Accepted: 03/01/2012] [Indexed: 01/05/2023]
Abstract
Macroautophagy (autophagy) is a lysosomal degradation pathway that is conserved from yeast to humans that plays an important role in recycling cellular constituents in all cells. A number of protein complexes and signaling pathways impinge on the regulation of autophagy, with the mammalian target of rapamycin (mTOR) as the central player in the canonical pathway. Cytoplasmic Ca(2+) signaling also regulates autophagy, with both activating and inhibitory effects, mediated by the canonical as well as non-canonical pathways. Here we review this regulation, with a focus on the role of an mTOR-independent pathway that involves the inositol trisphosphate receptor (InsP(3)R) Ca(2+) release channel and Ca(2+) signaling to mitochondria. Constitutive InsP(3)R Ca(2+) transfer to mitochondria is required for autophagy suppression in cells in nutrient-replete media. In its absence, cells become metabolically compromised due to insufficient production of reducing equivalents to support oxidative phosphorylation. Absence of this Ca(2+) transfer to mitochondria results in activation of AMPK, which activates mTOR-independent pro-survival autophagy. Constitutive InsP(3)R Ca(2+) release to mitochondria is an essential cellular process that is required for efficient mitochondrial respiration, maintenance of normal cell bioenergetics and suppression of autophagy.
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1404
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Mitochondrial Ca(2+) mobilization is a key element in olfactory signaling. Nat Neurosci 2012; 15:754-62. [PMID: 22446879 DOI: 10.1038/nn.3074] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 02/21/2012] [Indexed: 12/13/2022]
Abstract
In olfactory sensory neurons (OSNs), cytosolic Ca(2+) controls the gain and sensitivity of olfactory signaling. Important components of the molecular machinery that orchestrates OSN Ca(2+) dynamics have been described, but key details are still missing. Here, we demonstrate a critical physiological role of mitochondrial Ca(2+) mobilization in mouse OSNs. Combining a new mitochondrial Ca(2+) imaging approach with patch-clamp recordings, organelle mobility assays and ultrastructural analyses, our study identifies mitochondria as key determinants of olfactory signaling. We show that mitochondrial Ca(2+) mobilization during sensory stimulation shapes the cytosolic Ca(2+) response profile in OSNs, ensures a broad dynamic response range and maintains sensitivity of the spike generation machinery. When mitochondrial function is impaired, olfactory neurons function as simple stimulus detectors rather than as intensity encoders. Moreover, we describe activity-dependent recruitment of mitochondria to olfactory knobs, a mechanism that provides a context-dependent tool for OSNs to maintain cellular homeostasis and signaling integrity.
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1405
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Palty R, Sekler I. The mitochondrial Na(+)/Ca(2+) exchanger. Cell Calcium 2012; 52:9-15. [PMID: 22430014 DOI: 10.1016/j.ceca.2012.02.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 02/24/2012] [Accepted: 02/27/2012] [Indexed: 01/20/2023]
Abstract
Powered by the steep mitochondrial membrane potential Ca(2+) permeates into the mitochondria via the Ca(2+) uniporter and is then extruded by a mitochondrial Na(+)/Ca(2+) exchanger. This mitochondrial Ca(2+) shuttling regulates the rate of ATP production and participates in cellular Ca(2+) signaling. Despite the fact that the exchanger was functionally identified 40 years ago its molecular identity remained a mystery. Early studies on isolated mitochondria and intact cells characterized the functional properties of a mitochondrial Na(+)/Ca(2+) exchanger, and showed that it possess unique functional fingerprints such as Li(+)/Ca(2+) exchange and that it is displaying selective sensitivity to inhibitors. Purification of mitochondria proteins combined with functional reconstitution led to the isolation of a polypeptide candidate of the exchanger but failed to molecularly identify it. A turning point in the search for the exchanger molecule came with the recent cloning of the last member of the Na(+)/Ca(2+) exchanger superfamily termed NCLX (Na(+)/Ca(2+)/Li(+) exchanger). NCLX is localized in the inner mitochondria membrane and its expression is linked to mitochondria Na(+)/Ca(2+) exchange matching the functional fingerprints of the putative mitochondrial Na(+)/Ca(2+) exchanger. Thus NCLX emerges as the long sought mitochondria Na(+)/Ca(2+) exchanger and provide a critical molecular handle to study mitochondrial Ca(2+) signaling and transport. Here we summarize some of the main topics related to the molecular properties of the Na(+)/Ca(2+) exchanger, beginning with the early days of its functional identification, its kinetic properties and regulation, and culminating in its molecular identification.
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Affiliation(s)
- Raz Palty
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA.
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1406
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Quintana A, Hoth M. Mitochondrial dynamics and their impact on T cell function. Cell Calcium 2012; 52:57-63. [PMID: 22425631 DOI: 10.1016/j.ceca.2012.02.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 02/14/2012] [Accepted: 02/15/2012] [Indexed: 12/23/2022]
Abstract
Energy supply is the most prominent function of mitochondria, but in addition, mitochondria are indispensable for a multitude of other important cellular functions including calcium (Ca(2+)) signaling and buffering, the supply of metabolites and the sequestration of apoptotic factors. The efficiency of those functions highly depends on the proper positioning of mitochondria within the cytosol. In lymphocytes, mitochondria preferentially localize into the vicinity (∼200nm) of the immune synapse (IS). This localization is regulated by motor-based cytoskeleton-mediated transport, the fusion/fission dynamics of mitochondria, and probably also through tethering with the ER. IS formation also induces the accumulation of CRAC/ORAI1 Ca(2+) channels, the CRAC/ORAI channel activator STIM1, K(+) channels and plasma membrane Ca(2+) ATPase (PMCA) within the IS. Such a large agglomeration of Ca(2+) binding organelles and proteins highlights the IS as a critical cellular compartment for Ca(2+) dependent lymphocyte activation. At the IS, Ca(2+) microdomains generated beneath open CRAC/ORAI channels provide a rapid, robust and reliable mechanism for driving cellular responses in mast cells and T cells. Here, we discuss the relevance of motor-based mitochondrial transport, fusion, fission and tethering for mitochondrial localization in T cells and the importance of subplasmalemmal mitochondria to control local CRAC/ORAI1-dependent Ca(2+) microdomains at the IS for efficient T lymphocyte activation.
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Affiliation(s)
- Ariel Quintana
- La Jolla Institute for Allergy& Immunology, La Jolla, CA 92037, USA
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1407
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Bakowski D, Nelson C, Parekh AB. Endoplasmic reticulum-mitochondria coupling: local Ca²⁺ signalling with functional consequences. Pflugers Arch 2012; 464:27-32. [PMID: 22415215 DOI: 10.1007/s00424-012-1095-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 02/20/2012] [Accepted: 03/01/2012] [Indexed: 12/12/2022]
Abstract
Plasma membrane store-operated Ca²⁺ release-activated Ca²⁺ (CRAC) channels are a widespread and conserved Ca²⁺ influx pathway, driving activation of a range of spatially and temporally distinct cellular responses. Although CRAC channels are activated by the loss of Ca²⁺ from the endoplasmic reticulum, their gating is regulated by mitochondria. Through their ability to buffer cytoplasmic Ca²⁺, mitochondria take up Ca²⁺ released from the endoplasmic reticulum by InsP₃ receptors, leading to more extensive store depletion and stronger activation of CRAC channels. Mitochondria also buffer Ca²⁺ that enters through CRAC channels, reducing Ca²⁺-dependent slow inactivation of the channels. In addition, depolarised mitochondria impair movement of the CRAC channel activating protein STIM1 across the endoplasmic reticulum membrane. Because they regulate CRAC channel activity, particularly Ca²⁺-dependent slow inactivation, mitochondria influence CRAC channel-driven enzyme activation, secretion and gene expression. Mitochondrial regulation of CRAC channels therefore provides an important control element to the regulation of intracellular Ca²⁺ signalling.
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Affiliation(s)
- Daniel Bakowski
- Department of Physiology, Anatomy and Genetics Sherrington Building, South Parks Road, Oxford, OX1 3PT, UK
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1408
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Spät A, Szanda G. Special features of mitochondrial Ca²⁺ signalling in adrenal glomerulosa cells. Pflugers Arch 2012; 464:43-50. [PMID: 22395411 DOI: 10.1007/s00424-012-1086-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 02/10/2012] [Accepted: 02/14/2012] [Indexed: 11/30/2022]
Abstract
Aldosterone, secreted by adrenal glomerulosa cells, allows the adaptation of the vertebrate organism to a wide range of physiological and pathological stimuli including acute haemodynamic challenges and long-term changes in dietary sodium and potassium intake. Most of the extracellular signals are mediated by cytosolic Ca²⁺ signal deriving from Ca²⁺ release, store-operated and/or voltage-gated Ca²⁺ influx. Mitochondria in glomerulosa cells play a fundamental role in generating and modulating the final biological response. These organelles not only house several enzymes of aldosterone biosynthesis but also-in a Ca²⁺-dependent manner-provide NADPH for the function of these enzymes. Moreover, mitochondria, constituting a high portion of cytoplasmic volume and displaying a uniquely low-threshold Ca²⁺ sequestering ability, shape and thus modulate the decoding of the complex cytosolic Ca²⁺ response. The unusual features of mitochondrial Ca²⁺ signalling that permit such an integrative function in adrenal glomerulosa cells are hereby described.
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Affiliation(s)
- András Spät
- Department of Physiology, Semmelweis University, Budapest, Hungary.
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1409
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Abstract
Mitochondria are often regarded as the powerhouse of the cell by generating the ultimate energy transfer molecule, ATP, which is required for a multitude of cellular processes. However, the role of mitochondria goes beyond their capacity to create molecular fuel, to include the generation of reactive oxygen species, the regulation of calcium, and activation of cell death. Mitochondrial dysfunction is part of both normal and premature ageing, but can contribute to inflammation, cell senescence, and apoptosis. Cardiovascular disease, and in particular atherosclerosis, is characterized by DNA damage, inflammation, cell senescence, and apoptosis. Increasing evidence indicates that mitochondrial damage and dysfunction also occur in atherosclerosis and may contribute to the multiple pathological processes underlying the disease. This review summarizes the normal role of mitochondria, the causes and consequences of mitochondrial dysfunction, and the evidence for mitochondrial damage and dysfunction in vascular disease. Finally, we highlight areas of mitochondrial biology that may have therapeutic targets in vascular disease.
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Affiliation(s)
- Emma Yu
- Division of Cardiovascular Medicine, University of Cambridge, Box 110, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
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1410
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Szczepanowska J, Malinska D, Wieckowski MR, Duszynski J. Effect of mtDNA point mutations on cellular bioenergetics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:1740-6. [PMID: 22406627 DOI: 10.1016/j.bbabio.2012.02.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 02/13/2012] [Accepted: 02/14/2012] [Indexed: 10/28/2022]
Abstract
This overview discusses the results of research on the effects of most frequent mtDNA point mutations on cellular bioenergetics. Thirteen proteins coded by mtDNA are crucial for oxidative phosphorylation, 11 of them constitute key components of the respiratory chain complexes I, III and IV and 2 of mitochondrial ATP synthase. Moreover, pathogenic point mutations in mitochondrial tRNAs and rRNAs generate abnormal synthesis of the mtDNA coded proteins. Thus, pathogenic point mutations in mtDNA usually disturb the level of key parameter of the oxidative phosphorylation, i.e. the electric potential on the inner mitochondrial membrane (Δψ), and in a consequence calcium signalling and mitochondrial dynamics in the cell. Mitochondrial generation of reactive oxygen species is also modified in the mutated cells. The results obtained with cultured cells and describing biochemical consequences of mtDNA point mutations are full of contradictions. Still they help elucidate the biochemical basis of pathologies and provide a valuable tool for finding remedies in the future. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).
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Affiliation(s)
- Joanna Szczepanowska
- Department of Biochemsitry, Nencki Institute of Experimental Biology, Warsaw, Poland
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1411
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Moon SH, Jenkins CM, Liu X, Guan S, Mancuso DJ, Gross RW. Activation of mitochondrial calcium-independent phospholipase A2γ (iPLA2γ) by divalent cations mediating arachidonate release and production of downstream eicosanoids. J Biol Chem 2012; 287:14880-95. [PMID: 22389508 DOI: 10.1074/jbc.m111.336776] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Calcium-independent phospholipase A(2)γ (iPLA(2)γ) (PNPLA8) is the predominant phospholipase activity in mammalian mitochondria. However, the chemical mechanisms that regulate its activity are unknown. Here, we utilize iPLA(2)γ gain of function and loss of function genetic models to demonstrate the robust activation of iPLA(2)γ in murine myocardial mitochondria by Ca(2+) or Mg(2+) ions. Calcium ion stimulated the production of 2-arachidonoyl-lysophosphatidylcholine (2-AA-LPC) from 1-palmitoyl-2-[(14)C]arachidonoyl-sn-glycero-3-phosphocholine during incubations with wild-type heart mitochondrial homogenates. Furthermore, incubation of mitochondrial homogenates from transgenic myocardium expressing iPLA(2)γ resulted in 13- and 25-fold increases in the initial rate of radiolabeled 2-AA-LPC and arachidonic acid (AA) production, respectively, in the presence of calcium ion. Mass spectrometric analysis of the products of calcium-activated hydrolysis of endogenous mitochondrial phospholipids in transgenic iPLA(2)γ mitochondria revealed the robust production of AA, 2-AA-LPC, and 2-docosahexaenoyl-LPC that was over 10-fold greater than wild-type mitochondria. The mechanism-based inhibitor (R)-(E)-6-(bromomethylene)-3-(1-naphthalenyl)-2H-tetrahydropyran-2-one (BEL) (iPLA(2)γ selective), but not its enantiomer, (S)-BEL (iPLA(2)β selective) or pyrrolidine (cytosolic PLA(2)α selective), markedly attenuated Ca(2+)-dependent fatty acid release and polyunsaturated LPC production. Moreover, Ca(2+)-induced iPLA(2)γ activation was accompanied by the production of downstream eicosanoid metabolites that were nearly completely ablated by (R)-BEL or by genetic ablation of iPLA(2)γ. Intriguingly, Ca(2+)-induced iPLA(2)γ activation was completely inhibited by long-chain acyl-CoA (IC(50) ∼20 μm) as well as by a nonhydrolyzable acyl-CoA thioether analog. Collectively, these results demonstrate that mitochondrial iPLA(2)γ is activated by divalent cations and inhibited by acyl-CoA modulating the generation of biologically active metabolites that regulate mitochondrial bioenergetic and signaling functions.
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Affiliation(s)
- Sung Ho Moon
- Department of Medicine, Division of Bioorganic Chemistry and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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1412
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Segregation of calcium signalling mechanisms in magnocellular neurones and terminals. Cell Calcium 2012; 51:293-9. [DOI: 10.1016/j.ceca.2012.02.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 02/03/2012] [Indexed: 11/22/2022]
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1413
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Schwarzländer M, Logan DC, Johnston IG, Jones NS, Meyer AJ, Fricker MD, Sweetlove LJ. Pulsing of membrane potential in individual mitochondria: a stress-induced mechanism to regulate respiratory bioenergetics in Arabidopsis. THE PLANT CELL 2012; 24:1188-201. [PMID: 22395486 PMCID: PMC3336130 DOI: 10.1105/tpc.112.096438] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 02/02/2012] [Accepted: 02/16/2012] [Indexed: 05/19/2023]
Abstract
Mitochondrial ATP synthesis is driven by a membrane potential across the inner mitochondrial membrane; this potential is generated by the proton-pumping electron transport chain. A balance between proton pumping and dissipation of the proton gradient by ATP-synthase is critical to avoid formation of excessive reactive oxygen species due to overreduction of the electron transport chain. Here, we report a mechanism that regulates bioenergetic balance in individual mitochondria: a transient partial depolarization of the inner membrane. Single mitochondria in living Arabidopsis thaliana root cells undergo sporadic rapid cycles of partial dissipation and restoration of membrane potential, as observed by real-time monitoring of the fluorescence of the lipophilic cationic dye tetramethyl rhodamine methyl ester. Pulsing is induced in tissues challenged by high temperature, H(2)O(2), or cadmium. Pulses were coincident with a pronounced transient alkalinization of the matrix and are therefore not caused by uncoupling protein or by the opening of a nonspecific channel, which would lead to matrix acidification. Instead, a pulse is the result of Ca(2+) influx, which was observed coincident with pulsing; moreover, inhibitors of calcium transport reduced pulsing. We propose a role for pulsing as a transient uncoupling mechanism to counteract mitochondrial dysfunction and reactive oxygen species production.
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Affiliation(s)
- Markus Schwarzländer
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom.
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1414
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Spät A, Fülöp L, Szanda G. The role of mitochondrial Ca(2+) and NAD(P)H in the control of aldosterone secretion. Cell Calcium 2012; 52:64-72. [PMID: 22364774 DOI: 10.1016/j.ceca.2012.01.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 01/25/2012] [Accepted: 01/27/2012] [Indexed: 01/03/2023]
Abstract
The mineralocorticoid hormone aldosterone is synthesized in the zona glomerulosa of the adrenal cortex. Glomerulosa cells respond to the physiological stimuli, elevated extracellular [K(+)] and angiotensin II, with an intracellular Ca(2+) signal. Cytosolic Ca(2+) facilitates the transport of the steroid-precursor cholesterol to mitochondria and, after a few hours, it also induces the transcription of aldosterone synthase. Therefore, the cytosolic Ca(2+) signal is regarded as the most important short and long-term mediator of aldosterone secretion. However, cytosolic Ca(2+) is also taken up by mitochondria and, in turn, the mitochondrial Ca(2+) response activates mitochondrial dehydrogenases resulting in stimulation of respiration and increase in reduced pyridine nucleotides. Since both cholesterol side-chain cleavage and all of the hydroxylation steps of steroid synthesis require NADPH as a cofactor, the importance of cytosolic Ca(2+) - mitochondrial Ca(2+) coupling and of appropriate NADPH supply in respect to hormone production can be assumed. However, the importance of the mitochondrial factors has been neglected so far. Here, after summarizing earlier findings we provide new results obtained through modifying mitochondrial Ca(2+) uptake by knocking down p38 MAPK or OPA1 and overexpressing S100G, supporting the notion that mitochondrial Ca(2+) and reduced pyridine nucleotides are facilitating factors for both basal and stimulated steroid production.
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Affiliation(s)
- András Spät
- Department of Physiology, Faculty of Medicine, Semmelweis University, Hungary.
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1415
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Stael S, Wurzinger B, Mair A, Mehlmer N, Vothknecht UC, Teige M. Plant organellar calcium signalling: an emerging field. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:1525-42. [PMID: 22200666 PMCID: PMC3966264 DOI: 10.1093/jxb/err394] [Citation(s) in RCA: 207] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
This review provides a comprehensive overview of the established and emerging roles that organelles play in calcium signalling. The function of calcium as a secondary messenger in signal transduction networks is well documented in all eukaryotic organisms, but so far existing reviews have hardly addressed the role of organelles in calcium signalling, except for the nucleus. Therefore, a brief overview on the main calcium stores in plants-the vacuole, the endoplasmic reticulum, and the apoplast-is provided and knowledge on the regulation of calcium concentrations in different cellular compartments is summarized. The main focus of the review will be the calcium handling properties of chloroplasts, mitochondria, and peroxisomes. Recently, it became clear that these organelles not only undergo calcium regulation themselves, but are able to influence the Ca(2+) signalling pathways of the cytoplasm and the entire cell. Furthermore, the relevance of recent discoveries in the animal field for the regulation of organellar calcium signals will be discussed and conclusions will be drawn regarding potential homologous mechanisms in plant cells. Finally, a short overview on bacterial calcium signalling is included to provide some ideas on the question where this typically eukaryotic signalling mechanism could have originated from during evolution.
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Affiliation(s)
- Simon Stael
- Department of Biochemistry and Cell Biology, MFPL, University of Vienna, Dr Bohrgasse 9, A-1030 Vienna, Austria
| | - Bernhard Wurzinger
- Department of Biochemistry and Cell Biology, MFPL, University of Vienna, Dr Bohrgasse 9, A-1030 Vienna, Austria
| | - Andrea Mair
- Department of Biochemistry and Cell Biology, MFPL, University of Vienna, Dr Bohrgasse 9, A-1030 Vienna, Austria
| | - Norbert Mehlmer
- Department of Biology I, Botany, LMU Munich, Großhaderner Str. 2, D-82152 Planegg-Martinsried, Germany
| | - Ute C. Vothknecht
- Department of Biology I, Botany, LMU Munich, Großhaderner Str. 2, D-82152 Planegg-Martinsried, Germany
- Center for Integrated Protein Science (Munich) at the Department of Biology of the LMU Munich, D-81377 Munich, Germany
| | - Markus Teige
- Department of Biochemistry and Cell Biology, MFPL, University of Vienna, Dr Bohrgasse 9, A-1030 Vienna, Austria
- To whom correspondence should be addressed.
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1416
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Mitochondria and chromaffin cell function. Pflugers Arch 2012; 464:33-41. [PMID: 22278417 DOI: 10.1007/s00424-012-1074-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 01/05/2012] [Accepted: 01/09/2012] [Indexed: 10/14/2022]
Abstract
Chromaffin cells are an excellent model for stimulus-secretion coupling. Ca(2+) entry through plasma membrane voltage-operated Ca(2+) channels (VOCC) is the trigger for secretion, but the intracellular organelles contribute subtle nuances to the Ca(2+) signal. The endoplasmic reticulum amplifies the cytosolic Ca(2+) ([Ca(2+)](C)) signal by Ca(2+)-induced Ca(2+) release (CICR) and helps generation of microdomains with high [Ca(2+)](C) (HCMD) at the subplasmalemmal region. These HCMD induce exocytosis of the docked secretory vesicles. Mitochondria close to VOCC take up large amounts of Ca(2+) from HCMD and stop progression of the Ca(2+) wave towards the cell core. On the other hand, the increase of [Ca(2+)] at the mitochondrial matrix stimulates respiration and tunes energy production to the increased needs of the exocytic activity. At the end of stimulation, [Ca(2+)](C) decreases rapidly and mitochondria release the Ca(2+) accumulated in the matrix through the Na(+)/Ca(2+) exchanger. VOCC, CICR sites and nearby mitochondria form functional triads that co-localize at the subplasmalemmal area, where secretory vesicles wait ready for exocytosis. These triads optimize stimulus-secretion coupling while avoiding propagation of the Ca(2+) signal to the cell core. Perturbation of their functioning in neurons may contribute to the genesis of excitotoxicity, ageing mental retardation and/or neurodegenerative disorders.
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1417
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Saggu S, Hung HI, Quiogue G, Lemasters JJ, Nieminen AL. Lysosomal signaling enhances mitochondria-mediated photodynamic therapy in A431 cancer cells: role of iron. Photochem Photobiol 2012; 88:461-8. [PMID: 22220628 DOI: 10.1111/j.1751-1097.2012.01081.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In photodynamic therapy (PDT), light activates a photosensitizer added to a tissue, resulting in singlet oxygen formation and cell death. The photosensitizer phthalocyanine 4 (Pc 4) localizes primarily to mitochondrial membranes in cancer cells, resulting in mitochondria-mediated cell death. The aim of this study was to determine how lysosomes contribute to PDT-induced cell killing by mitochondria-targeted photosensitizers such as Pc 4. We monitored cell killing of A431 cells after Pc 4-PDT in the presence and absence of bafilomycin, an inhibitor of the vacuolar proton pump of lysosomes and endosomes. Bafilomycin was not toxic by itself, but greatly enhanced Pc 4-PDT-induced cell killing. To investigate whether iron loading of lysosomes affects bafilomycin-induced killing, cells were incubated with ammonium ferric citrate (30 μM) for 30 h prior to PDT. Ammonium ferric citrate enhanced Pc 4 plus bafilomycin-induced cell killing without having toxicity by itself. Iron chelators (desferrioxamine and starch-desferrioxamine) and the inhibitor of the mitochondrial calcium (and ferrous iron) uniporter, Ru360, protected against Pc 4 plus bafilomycin toxicity. These results support the conclusion that chelatable iron stored in the lysosomes enhances the efficacy of bafilomycin-mediated PDT and that lysosomal disruption augments PDT with Pc 4.
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Affiliation(s)
- Shalini Saggu
- Department of Pharmaceutical and Biomedical Sciences, Center for Cell Death, Injury and Regeneration, Medical University of South Carolina, Charleston, SC, USA
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1418
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Bononi A, Missiroli S, Poletti F, Suski JM, Agnoletto C, Bonora M, De Marchi E, Giorgi C, Marchi S, Patergnani S, Rimessi A, Wieckowski MR, Pinton P. Mitochondria-Associated Membranes (MAMs) as Hotspot Ca2+ Signaling Units. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 740:411-37. [DOI: 10.1007/978-94-007-2888-2_17] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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1419
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Calì T, Ottolini D, Brini M. Mitochondrial Ca(2+) as a key regulator of mitochondrial activities. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 942:53-73. [PMID: 22399418 DOI: 10.1007/978-94-007-2869-1_3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Mitochondria play a central role in cell biology, not only as producers of ATP but also as regulators of the Ca(2+) signal. The translocation by respiratory chain protein complexes of H(+) across the ion-impermeable inner membrane generates a very large H(+) electrochemical gradient that can be employed not only by the H(+) ATPase to run the endoergonic reaction of ADP phosphorylation, but also to accumulate cations into the matrix. Mitochondria can rapidly take up Ca(2+) through an electrogenic pathway, the uniporter, that acts to equilibrate Ca(2+) with its electrochemical gradient, and thus accumulates the cation into the matrix, and they can release it through two exchangers (with H(+) and Na(+), mostly expressed in non-excitable and excitable cells, respectively), that utilize the electrochemical gradient of the monovalent cations to prevent the attainment of electrical equilibrium.The uniporter, due to its low Ca(2+) affinity, demands high local Ca(2+) concentrations to work. In different cell systems these high Ca(2+) concentration microdomains are generated, upon cell stimulation, in proximity of the plasma membrane and the sarco/endoplasmic reticulum Ca(2+) channels.Recent work has revealed the central role of mitochondria in signal transduction pathways: evidence is accumulating that, by taking up Ca(2+), they not only modulate mitochondrial activities but also tune the cytosolic Ca(2+) signals and their related functions. This review analyses recent developments in the area of mitochondrial Ca(2+) signalling and attempts to summarize cell physiology aspects of the mitochondrial Ca(2+) transport machinery.
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Affiliation(s)
- Tito Calì
- Department of Comparative Biomedicine and Food Science, University of Padova, Padova, Italy
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1420
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Wallace DC. Bioenergetic origins of complexity and disease. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2011; 76:1-16. [PMID: 22194359 DOI: 10.1101/sqb.2011.76.010462] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The organizing power of energy flow is hypothesized to be the origin of biological complexity and its decline the basis of "complex" diseases and aging. Energy flow through organic systems creates nucleic acids, which store information, and the annual accumulation of information generates today's complexity. Energy flow through our bodies is mediated by the mitochondria, symbiotic bacteria whose genomes encompass the mitochondrial DNA (mtDNA) and more than 1000 nuclear genes. Inherited and/or epigenomic variation of the mitochondrial genome determines our initial energetic capacity, but the age-related accumulation of somatic cell mtDNA mutations further erodes energy flow, leading to disease. This bioenergetic perspective on disease provides a unifying pathophysiological and genetic mechanism for neuropsychiatric diseases such as Alzheimer and Parkinson Disease, metabolic diseases such as diabetes and obesity, autoimmune diseases, aging, and cancer.
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Affiliation(s)
- D C Wallace
- Center for Mitochondrial and Epigenomic Medicine, Children's Hospital of Philadelphia Research Institute and Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104-4302, USA.
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1421
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1422
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Wojtovich AP, Sherman TA, Nadtochiy SM, Urciuoli WR, Brookes PS, Nehrke K. SLO-2 is cytoprotective and contributes to mitochondrial potassium transport. PLoS One 2011; 6:e28287. [PMID: 22145034 PMCID: PMC3228735 DOI: 10.1371/journal.pone.0028287] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 11/04/2011] [Indexed: 11/19/2022] Open
Abstract
Mitochondrial potassium channels are important mediators of cell protection against stress. The mitochondrial large-conductance "big" K(+) channel (mBK) mediates the evolutionarily-conserved process of anesthetic preconditioning (APC), wherein exposure to volatile anesthetics initiates protection against ischemic injury. Despite the role of the mBK in cardioprotection, the molecular identity of the channel remains unknown. We investigated the attributes of the mBK using C. elegans and mouse genetic models coupled with measurements of mitochondrial K(+) transport and APC. The canonical Ca(2+)-activated BK (or "maxi-K") channel SLO1 was dispensable for both mitochondrial K(+) transport and APC in both organisms. Instead, we found that the related but physiologically-distinct K(+) channel SLO2 was required, and that SLO2-dependent mitochondrial K(+) transport was triggered directly by volatile anesthetics. In addition, a SLO2 channel activator mimicked the protective effects of volatile anesthetics. These findings suggest that SLO2 contributes to protection from hypoxic injury by increasing the permeability of the mitochondrial inner membrane to K(+).
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Affiliation(s)
- Andrew P. Wojtovich
- Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Teresa A. Sherman
- Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Sergiy M. Nadtochiy
- Department of Anesthesiology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - William R. Urciuoli
- Department of Anesthesiology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Paul S. Brookes
- Department of Anesthesiology, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Keith Nehrke
- Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York, United States of America
- * E-mail:
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1423
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Ong SB, Gustafsson AB. New roles for mitochondria in cell death in the reperfused myocardium. Cardiovasc Res 2011; 94:190-6. [PMID: 22108916 DOI: 10.1093/cvr/cvr312] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Mitochondria play an important role in regulating the life and death of cells. They provide the cell with energy via oxidative phosphorylation but can quickly turn into death-promoting organelles in response to stress by disrupting adenosine triphosphate synthesis, releasing pro-death proteins, and producing reactive oxygen species. Due to their high-energy requirement, cardiac myocytes are abundant in mitochondria and as a result, particularly vulnerable to mitochondrial defects. Myocardial ischaemia and reperfusion are associated with mitochondrial dysfunction and cell death. Therefore, future therapies will focus on preserving mitochondrial integrity and function in hopes of minimizing the impact of ischaemia/reperfusion (I/R) injury. It is well established that myocardial I/R activates both necrosis and apoptosis, and that blocking either process reduces the levels of injury. However, recent studies have demonstrated that alterations in mitochondrial dynamics or clearance of mitochondria via autophagy also can contribute to cell death in the myocardium. In this review, we will discuss these new developments and their impact on the role of cardiac mitochondria in cell death following reperfusion in the heart.
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Affiliation(s)
- Sang-Bing Ong
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, CA 92093-0758, USA
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1424
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Szabò I, Leanza L, Gulbins E, Zoratti M. Physiology of potassium channels in the inner membrane of mitochondria. Pflugers Arch 2011; 463:231-46. [PMID: 22089812 DOI: 10.1007/s00424-011-1058-7] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Accepted: 10/30/2011] [Indexed: 02/06/2023]
Abstract
The inner membrane of the ATP-producing organelles of endosymbiotic origin, mitochondria, has long been considered to be poorly permeable to cations and anions, since the strict control of inner mitochondrial membrane permeability is crucial for efficient ATP synthesis. Over the past 30 years, however, it has become clear that various ion channels--along with antiporters and uniporters--are present in the mitochondrial inner membrane, although at rather low abundance. These channels are important for energy supply, and some are a decisive factor in determining whether a cell lives or dies. Their electrophysiological and pharmacological characterisations have contributed importantly to the ongoing elucidation of their pathophysiological roles. This review gives an overview of recent advances in our understanding of the functions of the mitochondrial potassium channels identified so far. Open issues concerning the possible molecular entities giving rise to the observed activities and channel protein targeting to mitochondria are also discussed.
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Affiliation(s)
- Ildikò Szabò
- Department of Biology, University of Padova, Padova, Italy.
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1425
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Trypanosomes and the solution to a 50-year mitochondrial calcium mystery. Trends Parasitol 2011; 28:31-7. [PMID: 22088944 DOI: 10.1016/j.pt.2011.10.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 10/19/2011] [Accepted: 10/19/2011] [Indexed: 12/29/2022]
Abstract
The ability of mitochondria to take up Ca(2+) was discovered 50 years ago. This calcium uptake, through a mitochondrial calcium uniporter (MCU), is important not only for the regulation of cellular ATP concentration but also for more complex pathways such as shaping Ca(2+) signals and the activation of programmed cell death. The molecular nature of the uniporter remained unknown for decades. By a comparative study of mitochondrial protein profiles of organisms lacking or possessing MCU, such as yeast in the former case and vertebrates and trypanosomes in the latter, two groups recently found the protein that possesses all the characteristics of the MCU. These results add another success story to the already substantial contributions of trypanosomes to mammalian biochemistry.
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1426
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Bogeski I, Kappl R, Kummerow C, Gulaboski R, Hoth M, Niemeyer BA. Redox regulation of calcium ion channels: Chemical and physiological aspects. Cell Calcium 2011; 50:407-23. [DOI: 10.1016/j.ceca.2011.07.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 07/26/2011] [Indexed: 02/07/2023]
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1427
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Chikando AC, Kettlewell S, Williams GS, Smith G, Lederer WJ. Ca2+ dynamics in the mitochondria - state of the art. J Mol Cell Cardiol 2011; 51:627-31. [PMID: 21864537 PMCID: PMC3814218 DOI: 10.1016/j.yjmcc.2011.08.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 08/05/2011] [Accepted: 08/06/2011] [Indexed: 01/24/2023]
Abstract
The importance of [Ca2+] in the mitochondrial matrix, [Ca2+]mito, had been proposed by early work of Carafoli and others [1 ], [2 ] and [3 ]. The key suggestion in the 1970s [4 ] was that regulatory [Ca2+]mito played a role in controlling the rate of activation of tricarboxylic acid cycle dehydrogenases, important in the regulation of ATP production by the electron transport chain (ETC) during oxidative phosphorylation. This view is now established [5 ] and [6 ] and the key questions currently debated are to what extent do the mitochondria acquire and release Ca2+, and what impact do mitochondria have on the dynamic Ca2+ signal in the cardiac ventricular myocyte [7 ]. Although investigations of Ca2+ dynamics in mitochondria have been problematic, disparate and inconclusive, they have also been both provocative and exciting. A recent special issue of this journal presented contrasting perspectives on the speed, extent and mechanisms of changes in [Ca2+]mito, and how these changes may influence cellular spatio-temporal [Ca2+]i dynamics [8 ]. An audio discussion is also available online [9 ]. The uncertain nature of the signaling pathways is noted in Table 1 (see below) which shows mitochondrial proteins and processes that are of current focus and which remain contentious. Each of the “items” listed is largely unsettled, or is a “work in progress”. There may be advocates for opposing positions noted or recent discoveries that must still be tested at multiple levels by diverse laboratories. Currently, the first item, the mitochondrial sodium/calcium exchanger (NCLX) [10 ], appears the most solid with respect to the molecular identification and physiological function, whereas, the recently described candidates of the mitochondrial Ca2+ uniporter (MCU) [11 ] and [12 ] still need to be verified and broadly examined by the scientific community.
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1428
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Prole DL, Taylor CW. Identification of intracellular and plasma membrane calcium channel homologues in pathogenic parasites. PLoS One 2011; 6:e26218. [PMID: 22022573 PMCID: PMC3194816 DOI: 10.1371/journal.pone.0026218] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Accepted: 09/22/2011] [Indexed: 11/29/2022] Open
Abstract
Ca2+ channels regulate many crucial processes within cells and their abnormal activity can be damaging to cell survival, suggesting that they might represent attractive therapeutic targets in pathogenic organisms. Parasitic diseases such as malaria, leishmaniasis, trypanosomiasis and schistosomiasis are responsible for millions of deaths each year worldwide. The genomes of many pathogenic parasites have recently been sequenced, opening the way for rational design of targeted therapies. We analyzed genomes of pathogenic protozoan parasites as well as the genome of Schistosoma mansoni, and show the existence within them of genes encoding homologues of mammalian intracellular Ca2+ release channels: inositol 1,4,5-trisphosphate receptors (IP3Rs), ryanodine receptors (RyRs), two-pore Ca2+ channels (TPCs) and intracellular transient receptor potential (Trp) channels. The genomes of Trypanosoma, Leishmania and S. mansoni parasites encode IP3R/RyR and Trp channel homologues, and that of S. mansoni additionally encodes a TPC homologue. In contrast, apicomplexan parasites lack genes encoding IP3R/RyR homologues and possess only genes encoding TPC and Trp channel homologues (Toxoplasma gondii) or Trp channel homologues alone. The genomes of parasites also encode homologues of mammalian Ca2+influx channels, including voltage-gated Ca2+ channels and plasma membrane Trp channels. The genome of S. mansoni also encodes Orai Ca2+ channel and STIM Ca2+ sensor homologues, suggesting that store-operated Ca2+ entry may occur in this parasite. Many anti-parasitic agents alter parasite Ca2+ homeostasis and some are known modulators of mammalian Ca2+ channels, suggesting that parasite Ca2+ channel homologues might be the targets of some current anti-parasitic drugs. Differences between human and parasite Ca2+ channels suggest that pathogen-specific targeting of these channels may be an attractive therapeutic prospect.
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Affiliation(s)
- David L Prole
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom.
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1429
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von Stockum S, Basso E, Petronilli V, Sabatelli P, Forte MA, Bernardi P. Properties of Ca(2+) transport in mitochondria of Drosophila melanogaster. J Biol Chem 2011; 286:41163-41170. [PMID: 21984833 DOI: 10.1074/jbc.m111.268375] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have studied the pathways for Ca(2+) transport in mitochondria of the fruit fly Drosophila melanogaster. We demonstrate the presence of ruthenium red (RR)-sensitive Ca(2+) uptake, of RR-insensitive Ca(2+) release, and of Na(+)-stimulated Ca(2+) release in energized mitochondria, which match well characterized Ca(2+) transport pathways of mammalian mitochondria. Following larger matrix Ca(2+) loading Drosophila mitochondria underwent spontaneous RR-insensitive Ca(2+) release, an event that in mammals is due to opening of the permeability transition pore (PTP). Like the PTP of mammals, Drosophila Ca(2+)-induced Ca(2+) release could be triggered by uncoupler, diamide, and N-ethylmaleimide, indicating the existence of regulatory voltage- and redox-sensitive sites and was inhibited by tetracaine. Unlike PTP-mediated Ca(2+) release in mammals, however, it was (i) insensitive to cyclosporin A, ubiquinone 0, and ADP; (ii) inhibited by P(i), as is the PTP of yeast mitochondria; and (iii) not accompanied by matrix swelling and cytochrome c release even in KCl-based medium. We conclude that Drosophila mitochondria possess a selective Ca(2+) release channel with features intermediate between the PTP of yeast and mammals.
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Affiliation(s)
- Sophia von Stockum
- Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy
| | - Emy Basso
- Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy
| | - Valeria Petronilli
- Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy
| | - Patrizia Sabatelli
- Institute of Molecular Genetics at the Istituto Ortopedico Rizzoli, I-40126 Bologna, Italy
| | - Michael A Forte
- Vollum Institute, Oregon Health & Sciences University, Portland, Oregon 97239
| | - Paolo Bernardi
- Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy.
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1430
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Abstract
Mammalian skeletal muscle comprises different fiber types, whose identity is first established during embryonic development by intrinsic myogenic control mechanisms and is later modulated by neural and hormonal factors. The relative proportion of the different fiber types varies strikingly between species, and in humans shows significant variability between individuals. Myosin heavy chain isoforms, whose complete inventory and expression pattern are now available, provide a useful marker for fiber types, both for the four major forms present in trunk and limb muscles and the minor forms present in head and neck muscles. However, muscle fiber diversity involves all functional muscle cell compartments, including membrane excitation, excitation-contraction coupling, contractile machinery, cytoskeleton scaffold, and energy supply systems. Variations within each compartment are limited by the need of matching fiber type properties between different compartments. Nerve activity is a major control mechanism of the fiber type profile, and multiple signaling pathways are implicated in activity-dependent changes of muscle fibers. The characterization of these pathways is raising increasing interest in clinical medicine, given the potentially beneficial effects of muscle fiber type switching in the prevention and treatment of metabolic diseases.
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Affiliation(s)
- Stefano Schiaffino
- Venetian Institute of Molecular Medicine, Department of Biomedical Sciences, University of Padova, Consiglio Nazionale delle Ricerche Institute of Neurosciences, and Department of Human Anatomy and Physiology, University of Padova, Padova, Italy
| | - Carlo Reggiani
- Venetian Institute of Molecular Medicine, Department of Biomedical Sciences, University of Padova, Consiglio Nazionale delle Ricerche Institute of Neurosciences, and Department of Human Anatomy and Physiology, University of Padova, Padova, Italy
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1431
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Fülöp L, Szanda G, Enyedi B, Várnai P, Spät A. The effect of OPA1 on mitochondrial Ca²⁺ signaling. PLoS One 2011; 6:e25199. [PMID: 21980395 PMCID: PMC3182975 DOI: 10.1371/journal.pone.0025199] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 08/27/2011] [Indexed: 11/19/2022] Open
Abstract
The dynamin-related GTPase protein OPA1, localized in the intermembrane space and tethered to the inner membrane of mitochondria, participates in the fusion of these organelles. Its mutation is the most prevalent cause of Autosomal Dominant Optic Atrophy. OPA1 controls the diameter of the junctions between the boundary part of the inner membrane and the membrane of cristae and reduces the diffusibility of cytochrome c through these junctions. We postulated that if significant Ca²⁺ uptake into the matrix occurs from the lumen of the cristae, reduced expression of OPA1 would increase the access of Ca²⁺ to the transporters in the crista membrane and thus would enhance Ca²⁺ uptake. In intact H295R adrenocortical and HeLa cells cytosolic Ca²⁺ signals evoked with K⁺ and histamine, respectively, were transferred into the mitochondria. The rate and amplitude of mitochondrial [Ca²⁺] rise (followed with confocal laser scanning microscopy and FRET measurements with fluorescent wide-field microscopy) were increased after knockdown of OPA1, as compared with cells transfected with control RNA or mitofusin1 siRNA. Ca²⁺ uptake was enhanced despite reduced mitochondrial membrane potential. In permeabilized cells the rate of Ca²⁺ uptake by depolarized mitochondria was also increased in OPA1-silenced cells. The participation of Na⁺/Ca²⁺ and Ca²⁺/H⁺ antiporters in this transport process is indicated by pharmacological data. Altogether, our observations reveal the significance of OPA1 in the control of mitochondrial Ca²⁺ metabolism.
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Affiliation(s)
- László Fülöp
- Department of Physiology, Faculty of Medicine, Semmelweis University, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gergö Szanda
- Department of Physiology, Faculty of Medicine, Semmelweis University, Hungarian Academy of Sciences, Budapest, Hungary
| | - Balázs Enyedi
- Department of Physiology, Faculty of Medicine, Semmelweis University, Hungarian Academy of Sciences, Budapest, Hungary
| | - Péter Várnai
- Department of Physiology, Faculty of Medicine, Semmelweis University, Hungarian Academy of Sciences, Budapest, Hungary
| | - András Spät
- Department of Physiology, Faculty of Medicine, Semmelweis University, Hungarian Academy of Sciences, Budapest, Hungary
- Laboratory of Neurobiochemistry and Molecular Physiology, Hungarian Academy of Sciences, Budapest, Hungary
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1432
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Patergnani S, Suski JM, Agnoletto C, Bononi A, Bonora M, De Marchi E, Giorgi C, Marchi S, Missiroli S, Poletti F, Rimessi A, Duszynski J, Wieckowski MR, Pinton P. Calcium signaling around Mitochondria Associated Membranes (MAMs). Cell Commun Signal 2011; 9:19. [PMID: 21939514 PMCID: PMC3198985 DOI: 10.1186/1478-811x-9-19] [Citation(s) in RCA: 278] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 09/22/2011] [Indexed: 11/10/2022] Open
Abstract
Calcium (Ca2+) homeostasis is fundamental for cell metabolism, proliferation, differentiation, and cell death. Elevation in intracellular Ca2+ concentration is dependent either on Ca2+ influx from the extracellular space through the plasma membrane, or on Ca2+ release from intracellular Ca2+ stores, such as the endoplasmic/sarcoplasmic reticulum (ER/SR). Mitochondria are also major components of calcium signalling, capable of modulating both the amplitude and the spatio-temporal patterns of Ca2+ signals. Recent studies revealed zones of close contact between the ER and mitochondria called MAMs (Mitochondria Associated Membranes) crucial for a correct communication between the two organelles, including the selective transmission of physiological and pathological Ca2+ signals from the ER to mitochondria. In this review, we summarize the most up-to-date findings on the modulation of intracellular Ca2+ release and Ca2+ uptake mechanisms. We also explore the tight interplay between ER- and mitochondria-mediated Ca2+ signalling, covering the structural and molecular properties of the zones of close contact between these two networks.
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Affiliation(s)
- Simone Patergnani
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy.
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1433
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Dedkova EN, Blatter LA. Measuring mitochondrial function in intact cardiac myocytes. J Mol Cell Cardiol 2011; 52:48-61. [PMID: 21964191 DOI: 10.1016/j.yjmcc.2011.08.030] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 07/30/2011] [Accepted: 08/09/2011] [Indexed: 12/01/2022]
Abstract
Mitochondria are involved in cellular functions that go beyond the traditional role of these organelles as the power plants of the cell. Mitochondria have been implicated in several human diseases, including cardiac dysfunction, and play a role in the aging process. Many aspects of our knowledge of mitochondria stem from studies performed on the isolated organelle. Their relative inaccessibility imposes experimental difficulties to study mitochondria in their natural environment-the cytosol of intact cells-and has hampered a comprehensive understanding of the plethora of mitochondrial functions. Here we review currently available methods to study mitochondrial function in intact cardiomyocytes. These methods primarily use different flavors of fluorescent dyes and genetically encoded fluorescent proteins in conjunction with high-resolution imaging techniques. We review methods to study mitochondrial morphology, mitochondrial membrane potential, Ca(2+) and Na(+) signaling, mitochondrial pH regulation, redox state and ROS production, NO signaling, oxygen consumption, ATP generation and the activity of the mitochondrial permeability transition pore. Where appropriate we complement this review on intact myocytes with seminal studies that were performed on isolated mitochondria, permeabilized cells, and in whole hearts.
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Affiliation(s)
- Elena N Dedkova
- Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, IL 60612, USA
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1434
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After half a century mitochondrial calcium in- and efflux machineries reveal themselves. EMBO J 2011; 30:4119-25. [PMID: 21934651 DOI: 10.1038/emboj.2011.337] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 08/26/2011] [Indexed: 12/19/2022] Open
Abstract
Mitochondrial Ca(2+) uptake and release play a fundamental role in the control of different physiological processes, such as cytoplasmic Ca(2+) signalling, ATP production and hormone metabolism, while dysregulation of mitochondrial Ca(2+) handling triggers the cascade of events that lead to cell death. The basic mechanisms of mitochondrial Ca(2+) homeostasis have been firmly established for decades, but the molecular identities of the channels and transporters responsible for Ca(2+) uptake and release have remained mysterious until very recently. Here, we briefly review the main findings that have led to our present understanding of mitochondrial Ca(2+) homeostasis and its integration in cell physiology. We will then discuss the recent work that has unravelled the biochemical identity of three key molecules: NCLX, the mitochondrial Na(+)/Ca(2+) antiporter, MCU, the pore-forming subunit of the mitochondrial Ca(2+) uptake channel, and MICU1, one of its regulatory subunits.
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1435
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Mitochondrial matrix Ca2+ as an intrinsic signal regulating mitochondrial motility in axons. Proc Natl Acad Sci U S A 2011; 108:15456-61. [PMID: 21876166 DOI: 10.1073/pnas.1106862108] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The proper distribution of mitochondria is particularly vital for neurons because of their polarized structure and high energy demand. Mitochondria in axons constantly move in response to physiological needs, but signals that regulate mitochondrial movement are not well understood. Aside from producing ATP, Ca(2+) buffering is another main function of mitochondria. Activities of many enzymes in mitochondria are also Ca(2+)-dependent, suggesting that intramitochondrial Ca(2+) concentration is important for mitochondrial functions. Here, we report that mitochondrial motility in axons is actively regulated by mitochondrial matrix Ca(2+). Ca(2+) entry through the mitochondrial Ca(2+) uniporter modulates mitochondrial transport, and mitochondrial Ca(2+) content correlates inversely with the speed of mitochondrial movement. Furthermore, the miro1 protein plays a role in Ca(2+) uptake into the mitochondria, which subsequently affects mitochondrial movement.
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1436
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Korge P, Yang L, Yang JH, Wang Y, Qu Z, Weiss JN. Protective role of transient pore openings in calcium handling by cardiac mitochondria. J Biol Chem 2011; 286:34851-7. [PMID: 21859717 DOI: 10.1074/jbc.m111.239921] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Long-lasting mitochondrial permeability transition pore (mPTP) openings damage mitochondria, but transient mPTP openings protect against chronic cardiac stress. To probe the mechanism, we subjected isolated cardiac mitochondria to gradual Ca(2+) loading, which, in the absence of BSA, induced long-lasting mPTP opening, causing matrix depolarization. However, with BSA present to mimic cytoplasmic fatty acid-binding proteins, the mitochondrial population remained polarized and functional, even after matrix Ca(2+) release caused an extramitochondrial free [Ca(2+)] increase to >10 μM, unless mPTP openings were inhibited. These findings could be explained by asynchronous transient mPTP openings allowing individual mitochondria to depolarize long enough to flush accumulated matrix Ca(2+) and then to repolarize rapidly after pore closure. Because subsequent matrix Ca(2+) reuptake via the Ca(2+) uniporter is estimated to be >100-fold slower than matrix Ca(2+) release via mPTP, only a tiny fraction of mitochondria (<1%) are depolarized at any given time. Our results show that transient mPTP openings allow cardiac mitochondria to defend themselves collectively against elevated cytoplasmic Ca(2+) levels as long as respiratory chain activity is able to balance proton influx with proton pumping. We found that transient mPTP openings also stimulated reactive oxygen species production, which may engage reactive oxygen species-dependent cardioprotective signaling.
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Affiliation(s)
- Paavo Korge
- Cardiovascular Research Laboratory, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA
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1437
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García-Pérez C, Schneider TG, Hajnóczky G, Csordás G. Alignment of sarcoplasmic reticulum-mitochondrial junctions with mitochondrial contact points. Am J Physiol Heart Circ Physiol 2011; 301:H1907-15. [PMID: 21856920 DOI: 10.1152/ajpheart.00397.2011] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Propagation of ryanodine receptor (RyR2)-derived Ca(2+) signals to the mitochondrial matrix supports oxidative ATP production or facilitates mitochondrial apoptosis in cardiac muscle. Ca(2+) transfer likely occurs locally at focal associations of the sarcoplasmic reticulum (SR) and mitochondria, which are secured by tethers. The outer mitochondrial membrane and inner mitochondrial membrane (OMM and IMM, respectively) also form tight focal contacts (contact points) that are enriched in voltage-dependent anion channels, the gates of OMM for Ca(2+). Contact points could offer the shortest Ca(2+) transfer route to the matrix; however, their alignment with the SR-OMM associations remains unclear. Here, in rat heart we have studied the distribution of mitochondria-associated SR in submitochondrial membrane fractions and evaluated the colocalization of SR-OMM associations with contact points using transmission electron microscopy. In a sucrose gradient designed for OMM purification, biochemical assays revealed lighter fractions enriched in OMM only and heavier fractions containing OMM, IMM, and SR markers. Pure OMM fractions were enriched in mitofusin 2, an ~80 kDa mitochondrial fusion protein and SR-mitochondrial tether candidate, whereas in fractions of OMM + IMM + SR, a lighter (~50 kDa) band detected by antibodies raised against the NH(2) terminus of mitofusin 2 was dominating. Transmission electron microscopy revealed mandatory presence of contact points at the junctional SR-mitochondrial interface versus a random presence along matching SR-free OMM segments. For each SR-mitochondrial junction at least one tether was attached to contact points. These data establish the contact points as anchorage sites for the SR-mitochondrial physical coupling. Close coupling of the SR, OMM, and IMM is likely to provide a favorable spatial arrangement for local ryanodine receptor-mitochondrial Ca(2+) signaling.
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Affiliation(s)
- Cecília García-Pérez
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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1438
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Calcium microdomains at the immunological synapse: how ORAI channels, mitochondria and calcium pumps generate local calcium signals for efficient T-cell activation. EMBO J 2011; 30:3895-912. [PMID: 21847095 DOI: 10.1038/emboj.2011.289] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 07/19/2011] [Indexed: 12/24/2022] Open
Abstract
Cell polarization enables restriction of signalling into microdomains. Polarization of lymphocytes following formation of a mature immunological synapse (IS) is essential for calcium-dependent T-cell activation. Here, we analyse calcium microdomains at the IS with total internal reflection fluorescence microscopy. We find that the subplasmalemmal calcium signal following IS formation is sufficiently low to prevent calcium-dependent inactivation of ORAI channels. This is achieved by localizing mitochondria close to ORAI channels. Furthermore, we find that plasma membrane calcium ATPases (PMCAs) are re-distributed into areas beneath mitochondria, which prevented PMCA up-modulation and decreased calcium export locally. This nano-scale distribution-only induced following IS formation-maximizes the efficiency of calcium influx through ORAI channels while it decreases calcium clearance by PMCA, resulting in a more sustained NFAT activity and subsequent activation of T cells.
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Gouriou Y, Demaurex N, Bijlenga P, De Marchi U. Mitochondrial calcium handling during ischemia-induced cell death in neurons. Biochimie 2011; 93:2060-7. [PMID: 21846486 DOI: 10.1016/j.biochi.2011.08.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 08/03/2011] [Indexed: 12/18/2022]
Abstract
Mitochondria sense and shape cytosolic Ca(2+) signals by taking up and subsequently releasing Ca(2+) ions during physiological and pathological Ca(2+) elevations. Sustained elevations in the mitochondrial matrix Ca(2+) concentration are increasingly recognized as a defining feature of the intracellular cascade of lethal events that occur in neurons during cerebral ischemia. Here, we review the recently identified transport proteins that mediate the fluxes of Ca(2+) across mitochondria and discuss the implication of the permeability transition pore in decoding the abnormally sustained mitochondrial Ca(2+) elevations that occur during cerebral ischemia.
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Affiliation(s)
- Yves Gouriou
- Department of Cell Physiology and Metabolism, University of Geneva, rue Michel-Servet 1, Genève, Switzerland
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1440
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Pan S, Ryu SY, Sheu SS. Distinctive characteristics and functions of multiple mitochondrial Ca2+ influx mechanisms. SCIENCE CHINA-LIFE SCIENCES 2011; 54:763-9. [PMID: 21786199 DOI: 10.1007/s11427-011-4203-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Accepted: 06/27/2011] [Indexed: 01/23/2023]
Abstract
Intracellular Ca(2+) is vital for cell physiology. Disruption of Ca(2+) homeostasis contributes to human diseases such as heart failure, neuron-degeneration, and diabetes. To ensure an effective intracellular Ca(2+) dynamics, various Ca(2+) transport proteins localized in different cellular regions have to work in coordination. The central role of mitochondrial Ca(2+) transport mechanisms in responding to physiological Ca(2+) pulses in cytosol is to take up Ca(2+) for regulating energy production and shaping the amplitude and duration of Ca(2+) transients in various micro-domains. Since the discovery that isolated mitochondria can take up large quantities of Ca(2+) approximately 5 decades ago, extensive studies have been focused on the functional characterization and implication of ion channels that dictate Ca(2+) transport across the inner mitochondrial membrane. The mitochondrial Ca(2+) uptake sensitive to non-specific inhibitors ruthenium red and Ru360 has long been considered as the activity of mitochondrial Ca(2+) uniporter (MCU). The general consensus is that MCU is dominantly or exclusively responsible for the mitochondrial Ca(2+) influx. Since multiple Ca(2+) influx mechanisms (e.g. L-, T-, and N-type Ca(2+) channel) have their unique functions in the plasma membrane, it is plausible that mitochondrial inner membrane has more than just MCU to decode complex intracellular Ca(2+) signaling in various cell types. During the last decade, four molecular identities related to mitochondrial Ca(2+) influx mechanisms have been identified. These are mitochondrial ryanodine receptor, mitochondrial uncoupling proteins, LETM1 (Ca(2+)/H(+) exchanger), and MCU and its Ca(2+) sensing regulatory subunit MICU1. Here, we briefly review recent progress in these and other reported mitochondrial Ca(2+) influx pathways and their differences in kinetics, Ca(2+) dependence, and pharmacological characteristics. Their potential physiological and pathological implications are also discussed.
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Affiliation(s)
- Shi Pan
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Giorgi C, Agnoletto C, Bononi A, Bonora M, De Marchi E, Marchi S, Missiroli S, Patergnani S, Poletti F, Rimessi A, Suski JM, Wieckowski MR, Pinton P. Mitochondrial calcium homeostasis as potential target for mitochondrial medicine. Mitochondrion 2011; 12:77-85. [PMID: 21798374 PMCID: PMC3281195 DOI: 10.1016/j.mito.2011.07.004] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 06/10/2011] [Accepted: 07/11/2011] [Indexed: 11/28/2022]
Abstract
Mitochondria are crucial in different intracellular pathways of signal transduction. Mitochondria are capable of decoding a variety of extracellular stimuli into markedly different intracellular actions, ranging from energy production to cell death. The fine modulation of mitochondrial calcium (Ca2+) homeostasis plays a fundamental role in many of the processes involving this organelle. When mitochondrial Ca2+ homeostasis is compromised, different pathological conditions can occur, depending on the cell type involved. Recent data have shed light on the molecular identity of the main proteins involved in the handling of mitochondrial Ca2+ traffic, opening fascinating and ambitious new avenues for mitochondria-based pharmacological strategies.
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Affiliation(s)
- Carlotta Giorgi
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Chiara Agnoletto
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Angela Bononi
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Massimo Bonora
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Elena De Marchi
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Saverio Marchi
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Sonia Missiroli
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Simone Patergnani
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Federica Poletti
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Alessandro Rimessi
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Jan M. Suski
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
- Nencki Institute of Experimental Biology, Warsaw, Poland
| | | | - Paolo Pinton
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
- Corresponding author at: Department of Experimental and Diagnostic Medicine, Section of General Pathology, Via Borsari, 46 44100 Ferrara, Italy.
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Calcium: mitochondria channel calcium. Nat Rev Mol Cell Biol 2011; 12:463. [PMID: 21750571 DOI: 10.1038/nrm3156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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1443
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Fujimoto M, Hayashi T. New Insights into the Role of Mitochondria-Associated Endoplasmic Reticulum Membrane. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 292:73-117. [DOI: 10.1016/b978-0-12-386033-0.00002-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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