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Guo J, Wang Y, Shi C, Zhang D, Zhang Q, Wang L, Gong Z. Mitochondrial calcium uniporter complex: Unveiling the interplay between its regulators and calcium homeostasis. Cell Signal 2024; 121:111284. [PMID: 38964444 DOI: 10.1016/j.cellsig.2024.111284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/28/2024] [Accepted: 07/01/2024] [Indexed: 07/06/2024]
Abstract
The mitochondrial calcium uniporter complex (MCUc), serving as the specific channel for calcium influx into the mitochondrial matrix, is integral to calcium homeostasis and cellular integrity. Given its importance, ongoing research spans various disease models to understand the properties of the MCUc in pathophysiological contexts, but reported a different conclusion. Therefore, this review delves into the profound connection between MCUc-mediated calcium transients and cellular signaling pathways, mitochondrial dynamics, metabolism, and cell death. Additionally, we shed light on the recent advancements concerning the structural intricacies and auxiliary components of the MCUc in both resting and activated states. Furthermore, emphasis is placed on novel extrinsic and intrinsic regulators of the MCUc and their therapeutic implications across a spectrum of diseases. Meanwhile, we employed molecular docking simulations and identified candidate traditional Chinese medicine components with potential binding sites to the MCUc, potentially offering insights for further research on MCUc modulation.
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Affiliation(s)
- Jin Guo
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yukun Wang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Chunxia Shi
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Danmei Zhang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Qingqi Zhang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Luwen Wang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zuojiong Gong
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China.
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2
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Colussi DM, Stathopulos PB. The mitochondrial calcium uniporter: Balancing tumourigenic and anti-tumourigenic responses. J Physiol 2024; 602:3315-3339. [PMID: 38857425 DOI: 10.1113/jp285515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 05/20/2024] [Indexed: 06/12/2024] Open
Abstract
Increased malignancy and poor treatability associated with solid tumour cancers have commonly been attributed to mitochondrial calcium (Ca2+) dysregulation. The mitochondrial Ca2+ uniporter complex (mtCU) is the predominant mode of Ca2+ uptake into the mitochondrial matrix. The main components of mtCU are the pore-forming mitochondrial Ca2+ uniporter (MCU) subunit, MCU dominant-negative beta (MCUb) subunit, essential MCU regulator (EMRE) and the gatekeeping mitochondrial Ca2+ uptake 1 and 2 (MICU1 and MICU2) proteins. In this review, we describe mtCU-mediated mitochondrial Ca2+ dysregulation in solid tumour cancer types, finding enhanced mtCU activity observed in colorectal cancer, breast cancer, oral squamous cell carcinoma, pancreatic cancer, hepatocellular carcinoma and embryonal rhabdomyosarcoma. By contrast, decreased mtCU activity is associated with melanoma, whereas the nature of mtCU dysregulation remains unclear in glioblastoma. Furthermore, we show that numerous polymorphisms associated with cancer may alter phosphorylation sites on the pore forming MCU and MCUb subunits, which cluster at interfaces with EMRE. We highlight downstream/upstream biomolecular modulators of MCU and MCUb that alter mtCU-mediated mitochondrial Ca2+ uptake and may be used as biomarkers or to aid in the development of novel cancer therapeutics. Additionally, we provide an overview of the current small molecule inhibitors of mtCU that interact with the Asp residue of the critical Asp-Ile-Met-Glu motif or through other allosteric regulatory mechanisms to block Ca2+ permeation. Finally, we describe the relationship between MCU- and MCUb-mediating microRNAs and mitochondrial Ca2+ uptake that should be considered in the discovery of new treatment approaches for cancer.
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Affiliation(s)
- Danielle M Colussi
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
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3
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Noble M, Colussi DM, Junop M, Stathopulos PB. The MCU and MCUb amino-terminal domains tightly interact: mechanisms for low conductance assembly of the mitochondrial calcium uniporter complex. iScience 2024; 27:109699. [PMID: 38706857 PMCID: PMC11068563 DOI: 10.1016/j.isci.2024.109699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 02/12/2024] [Accepted: 04/05/2024] [Indexed: 05/07/2024] Open
Abstract
The mitochondrial calcium (Ca2+) uniporter (MCU) complex is regulated via integration of the MCU dominant negative beta subunit (MCUb), a low conductance paralog of the main MCU pore forming protein. The MCU amino (N)-terminal domain (NTD) also modulates channel function through cation binding to the MCU regulating acidic patch (MRAP). MCU and MCUb have high sequence similarities, yet the structural and functional roles of MCUb-NTD remain unknown. Here, we report that MCUb-NTD exhibits α-helix/β-sheet structure with a high thermal stability, dependent on protein concentration. Remarkably, MCU- and MCUb-NTDs heteromerically interact with ∼nM affinity, increasing secondary structure and stability and structurally perturbing MRAP. Further, we demonstrate MCU and MCUb co-localization is suppressed upon NTD deletion concomitant with increased mitochondrial Ca2+ uptake. Collectively, our data show that MCU:MCUb NTD tight interactions are promoted by enhanced regular structure and stability, augmenting MCU:MCUb co-localization, lowering mitochondrial Ca2+ uptake and implicating an MRAP-sensing mechanism.
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Affiliation(s)
- Megan Noble
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
| | - Danielle M. Colussi
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
| | - Murray Junop
- Department of Biochemistry, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
| | - Peter B. Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
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4
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Wang J, Jiang J, Hu H, Chen L. MCU complex: Exploring emerging targets and mechanisms of mitochondrial physiology and pathology. J Adv Res 2024:S2090-1232(24)00075-4. [PMID: 38417574 DOI: 10.1016/j.jare.2024.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/16/2024] [Accepted: 02/17/2024] [Indexed: 03/01/2024] Open
Abstract
BACKGROUND Globally, the onset and progression of multiple human diseases are associated with mitochondrial dysfunction and dysregulation of Ca2+ uptake dynamics mediated by the mitochondrial calcium uniporter (MCU) complex, which plays a key role in mitochondrial dysfunction. Despite relevant studies, the underlying pathophysiological mechanisms have not yet been fully elucidated. AIM OF REVIEW This article provides an in-depth analysis of the current research status of the MCU complex, focusing on its molecular composition, regulatory mechanisms, and association with diseases. In addition, we conducted an in-depth analysis of the regulatory effects of agonists, inhibitors, and traditional Chinese medicine (TCM) monomers on the MCU complex and their application prospects in disease treatment. From the perspective of medicinal chemistry, we conducted an in-depth analysis of the structure-activity relationship between these small molecules and MCU and deduced potential pharmacophores and binding pockets. Simultaneously, key structural domains of the MCU complex in Homo sapiens were identified. We also studied the functional expression of the MCU complex in Drosophila, Zebrafish, and Caenorhabditis elegans. These analyses provide a basis for exploring potential treatment strategies targeting the MCU complex and provide strong support for the development of future precision medicine and treatments. KEY SCIENTIFIC CONCEPTS OF REVIEW The MCU complex exhibits varying behavior across different tissues and plays various roles in metabolic functions. It consists of six MCU subunits, an essential MCU regulator (EMRE), and solute carrier 25A23 (SLC25A23). They regulate processes, such as mitochondrial Ca2+ (mCa2+) uptake, mitochondrial adenosine triphosphate (ATP) production, calcium dynamics, oxidative stress (OS), and cell death. Regulation makes it a potential target for treating diseases, especially cardiovascular diseases, neurodegenerative diseases, inflammatory diseases, metabolic diseases, and tumors.
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Affiliation(s)
- Jin Wang
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical College, University of South China, Hengyang 421001, China
| | - Jinyong Jiang
- Department of Pharmacy, The First Affiliated Hospital of Jishou University, Jishou 416000, China
| | - Haoliang Hu
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical College, University of South China, Hengyang 421001, China; College of Medicine, Hunan University of Arts and Science, Changde 415000, China.
| | - Linxi Chen
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical College, University of South China, Hengyang 421001, China.
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5
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Li C, Sun J, Zhang X, Zhou M, Gan X. Implications of MCU complex in metabolic diseases. FASEB J 2023; 37:e23046. [PMID: 37389546 DOI: 10.1096/fj.202300218r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 05/17/2023] [Accepted: 06/07/2023] [Indexed: 07/01/2023]
Abstract
Metabolic diseases are considered the primary culprit for physical and mental health of individuals. Although the diagnosis of these diseases is relatively easy, more effective and convenient potent drugs are still being explored. Ca2+ across the inner mitochondrial membrane is a vital intracellular messenger that regulates energy metabolism and cellular Ca2+ homeostasis and is involved in cell death. Mitochondria rely on a selective mitochondrial Ca2+ unidirectional transport complex (MCU complex) in their inner membrane for Ca2+ uptake. We found that the channel contains several subunits and undergoes dramatic transformations in various pathological processes, especially in metabolic diseases. In this way, we believe that the MCU complex becomes a target with significant potential for these diseases. However, there is no review linking the two factors, thus hindering the possibility of new drug production. Here, we highlight the connection between MCU complex-related Ca2+ transport and the pathophysiology of metabolic diseases, adding understanding and insight at the molecular level to provide new insights for targeting MCU to reverse metabolism-related diseases.
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Affiliation(s)
- Chen Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Jiyu Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xidan Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Min Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xueqi Gan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
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6
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De Mario A, D'Angelo D, Zanotti G, Raffaello A, Mammucari C. The mitochondrial calcium uniporter complex–A play in five acts. Cell Calcium 2023; 112:102720. [PMID: 37001308 DOI: 10.1016/j.ceca.2023.102720] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 03/30/2023]
Abstract
Mitochondrial Ca2+ (mitCa2+) uptake controls both intraorganellar and cytosolic functions. Within the organelle, [Ca2+] increases regulate the activity of tricarboxylic acid (TCA) cycle enzymes, thus sustaining oxidative metabolism and ATP production. Reactive oxygen species (ROS) are also generated as side products of oxygen consumption. At the same time, mitochondria act as buffers of cytosolic Ca2+ (cytCa2+) increases, thus regulating Ca2+-dependent cellular processes. In pathological conditions, mitCa2+ overload triggers the opening of the mitochondrial permeability transition pore (mPTP) and the release of apoptotic cofactors. MitCa2+ uptake occurs in response of local [Ca2+] increases in sites of proximity between the endoplasmic reticulum (ER) and the mitochondria and is mediated by the mitochondrial Ca2+ uniporter (MCU), a highly selective channel of the inner mitochondrial membrane (IMM). Both channel and regulatory subunits form the MCU complex (MCUC). Cryogenic electron microscopy (Cryo-EM) and crystal structures revealed the correct assembly of MCUC and the function of critical residues for the regulation of Ca2+ conductance.
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7
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MacEwen MJ, Sancak Y. Beyond the matrix: structural and physiological advancements in mitochondrial calcium signaling. Biochem Soc Trans 2023; 51:665-673. [PMID: 36960768 PMCID: PMC10212541 DOI: 10.1042/bst20220317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/25/2023]
Abstract
Mitochondrial calcium (Ca2+) signaling has long been known to regulate diverse cellular functions, ranging from ATP production via oxidative phosphorylation, to cytoplasmic Ca2+ signaling to apoptosis. Central to mitochondrial Ca2+ signaling is the mitochondrial Ca2+ uniporter complex (MCUC) which enables Ca2+ flux from the cytosol into the mitochondrial matrix. Several pivotal discoveries over the past 15 years have clarified the identity of the proteins comprising MCUC. Here, we provide an overview of the literature on mitochondrial Ca2+ biology and highlight recent findings on the high-resolution structure, dynamic regulation, and new functions of MCUC, with an emphasis on publications from the last five years. We discuss the importance of these findings for human health and the therapeutic potential of targeting mitochondrial Ca2+ signaling.
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Affiliation(s)
| | - Yasemin Sancak
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
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8
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Villot C, Lao KU. Electronic structure theory on modeling short-range noncovalent interactions between amino acids. J Chem Phys 2023; 158:094301. [PMID: 36889981 DOI: 10.1063/5.0138032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
While short-range noncovalent interactions (NCIs) are proving to be of importance in many chemical and biological systems, these atypical bindings happen within the so-called van der Waals envelope and pose an enormous challenge for current computational methods. We introduce SNCIAA, a database of 723 benchmark interaction energies of short-range noncovalent interactions between neutral/charged amino acids originated from protein x-ray crystal structures at the "gold standard" coupled-cluster with singles, doubles, and perturbative triples/complete basis set [CCSD(T)/CBS] level of theory with a mean absolute binding uncertainty less than 0.1 kcal/mol. Subsequently, a systematic assessment of commonly used computational methods, such as the second-order Møller-Plesset theory (MP2), density functional theory (DFT), symmetry-adapted perturbation theory (SAPT), composite electronic-structure methods, semiempirical approaches, and the physical-based potentials with machine learning (IPML) on SNCIAA is carried out. It is shown that the inclusion of dispersion corrections is essential even though these dimers are dominated by electrostatics, such as hydrogen bondings and salt bridges. Overall, MP2, ωB97M-V, and B3LYP+D4 turned out to be the most reliable methods for the description of short-range NCIs even in strongly attractive/repulsive complexes. SAPT is also recommended in describing short-range NCIs only if the δMP2 correction has been included. The good performance of IPML for dimers at close-equilibrium and long-range conditions is not transferable to the short-range. We expect that SNCIAA will assist the development/improvement/validation of computational methods, such as DFT, force-fields, and ML models, in describing NCIs across entire potential energy surfaces (short-, intermediate-, and long-range NCIs) on the same footing.
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Affiliation(s)
- Corentin Villot
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
| | - Ka Un Lao
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
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9
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Delgado BD, Long SB. Mechanisms of ion selectivity and throughput in the mitochondrial calcium uniporter. SCIENCE ADVANCES 2022; 8:eade1516. [PMID: 36525497 PMCID: PMC9757755 DOI: 10.1126/sciadv.ade1516] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
The mitochondrial calcium uniporter, which regulates aerobic metabolism by catalyzing mitochondrial Ca2+ influx, is arguably the most selective ion channel known. The mechanisms for this exquisite Ca2+ selectivity have not been defined. Here, using a reconstituted system, we study the electrical properties of the channel's minimal Ca2+-conducting complex, MCU-EMRE, from Tribolium castaneum to probe ion selectivity mechanisms. The wild-type TcMCU-EMRE complex recapitulates hallmark electrophysiological properties of endogenous Uniporter channels. Through interrogation of pore-lining mutants, we find that a ring of glutamate residues, the "E-locus," serves as the channel's selectivity filter. Unexpectedly, a nearby "D-locus" at the mouth of the pore has diminutive influence on selectivity. Anomalous mole fraction effects indicate that multiple Ca2+ ions are accommodated within the E-locus. By facilitating ion-ion interactions, the E-locus engenders both exquisite Ca2+ selectivity and high ion throughput. Direct comparison with structural information yields the basis for selective Ca2+ conduction by the channel.
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Affiliation(s)
- Bryce D. Delgado
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
- Graduate Program in Biochemistry and Structural Biology, Cell and Developmental Biology, and Molecular Biology, Weill Cornell Medicine Graduate School of Medical Sciences, New York, NY 10065, USA
| | - Stephen B. Long
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
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10
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Ruberti C, Feitosa-Araujo E, Xu Z, Wagner S, Grenzi M, Darwish E, Lichtenauer S, Fuchs P, Parmagnani AS, Balcerowicz D, Schoenaers S, de la Torre C, Mekkaoui K, Nunes-Nesi A, Wirtz M, Vissenberg K, Van Aken O, Hause B, Costa A, Schwarzländer M. MCU proteins dominate in vivo mitochondrial Ca2+ uptake in Arabidopsis roots. THE PLANT CELL 2022; 34:4428-4452. [PMID: 35938694 PMCID: PMC9614509 DOI: 10.1093/plcell/koac242] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Ca2+ signaling is central to plant development and acclimation. While Ca2+-responsive proteins have been investigated intensely in plants, only a few Ca2+-permeable channels have been identified, and our understanding of how intracellular Ca2+ fluxes is facilitated remains limited. Arabidopsis thaliana homologs of the mammalian channel-forming mitochondrial calcium uniporter (MCU) protein showed Ca2+ transport activity in vitro. Yet, the evolutionary complexity of MCU proteins, as well as reports about alternative systems and unperturbed mitochondrial Ca2+ uptake in knockout lines of MCU genes, leave critical questions about the in vivo functions of the MCU protein family in plants unanswered. Here, we demonstrate that MCU proteins mediate mitochondrial Ca2+ transport in planta and that this mechanism is the major route for fast Ca2+ uptake. Guided by the subcellular localization, expression, and conservation of MCU proteins, we generated an mcu triple knockout line. Using Ca2+ imaging in living root tips and the stimulation of Ca2+ transients of different amplitudes, we demonstrated that mitochondrial Ca2+ uptake became limiting in the triple mutant. The drastic cell physiological phenotype of impaired subcellular Ca2+ transport coincided with deregulated jasmonic acid-related signaling and thigmomorphogenesis. Our findings establish MCUs as a major mitochondrial Ca2+ entry route in planta and link mitochondrial Ca2+ transport with phytohormone signaling.
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Affiliation(s)
| | - Elias Feitosa-Araujo
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, D-48143, Germany
| | - Zhaolong Xu
- Department of Biosciences, University of Milano, Milan, I-20133, Italy
- Jiangsu Provincial Key Laboratory of Agrobiology, Institute of Germplasm Resources and Biotechnology, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China
| | | | - Matteo Grenzi
- Department of Biosciences, University of Milano, Milan, I-20133, Italy
| | - Essam Darwish
- Department of Biology, Lund University, Lund, 22362, Sweden
- Agricultural Botany Department, Faculty of Agriculture, Plant Physiology Section, Cairo University, Giza, 12613, Egypt
| | - Sophie Lichtenauer
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, D-48143, Germany
| | | | | | - Daria Balcerowicz
- Integrated Molecular Plant Physiology Research, University of Antwerp, Antwerp, B-2020, Belgium
| | - Sébastjen Schoenaers
- Integrated Molecular Plant Physiology Research, University of Antwerp, Antwerp, B-2020, Belgium
| | - Carolina de la Torre
- NGS Core Facility, Medical Faculty Mannheim, University of Heidelberg, Mannheim, D-68167, Germany
| | - Khansa Mekkaoui
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), D-06120, Germany
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil
| | - Markus Wirtz
- Centre for Organismal Studies (COS) Heidelberg, University of Heidelberg, Heidelberg, D-69120, Germany
| | - Kris Vissenberg
- Integrated Molecular Plant Physiology Research, University of Antwerp, Antwerp, B-2020, Belgium
- Department of Agriculture, Plant Biochemistry and Biotechnology Lab, Hellenic Mediterranean University, Heraklion, 71410, Greece
| | | | - Bettina Hause
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry (IPB), Halle (Saale), D-06120, Germany
| | - Alex Costa
- Authors for correspondence: (A.C); (M.S.)
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11
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Mitochondrial calcium uniporter stabilization preserves energetic homeostasis during Complex I impairment. Nat Commun 2022; 13:2769. [PMID: 35589699 PMCID: PMC9120069 DOI: 10.1038/s41467-022-30236-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 04/20/2022] [Indexed: 12/15/2022] Open
Abstract
Calcium entering mitochondria potently stimulates ATP synthesis. Increases in calcium preserve energy synthesis in cardiomyopathies caused by mitochondrial dysfunction, and occur due to enhanced activity of the mitochondrial calcium uniporter channel. The signaling mechanism that mediates this compensatory increase remains unknown. Here, we find that increases in the uniporter are due to impairment in Complex I of the electron transport chain. In normal physiology, Complex I promotes uniporter degradation via an interaction with the uniporter pore-forming subunit, a process we term Complex I-induced protein turnover. When Complex I dysfunction ensues, contact with the uniporter is inhibited, preventing degradation, and leading to a build-up in functional channels. Preventing uniporter activity leads to early demise in Complex I-deficient animals. Conversely, enhancing uniporter stability rescues survival and function in Complex I deficiency. Taken together, our data identify a fundamental pathway producing compensatory increases in calcium influx during Complex I impairment.
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12
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Li J, Sun M, Liu Y, Sun X, Yin K. Genome-Wide Identification of Wild Soybean Mitochondrial Calcium Uniporter Family Genes and Their Responses to Cold and Carbonate Alkaline Stresses. FRONTIERS IN PLANT SCIENCE 2022; 13:867503. [PMID: 35592573 PMCID: PMC9111538 DOI: 10.3389/fpls.2022.867503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 04/13/2022] [Indexed: 06/15/2023]
Abstract
The mitochondrial calcium uniporter (MCU), as an important component of the Ca2+ channel uniporter complex, plays a regulatory role in intracellular Ca2+ signal transduction. However, only a few studies to date have investigated plant MCU genes. In this study, we identified the MCU family genes in wild soybean and investigated their expression under cold and carbonate alkaline stresses. Eleven Glycine soja MCU genes (GsMCUs) were identified and clustered into two subgroups (subgroups I and II), and subgroup II could be further divided into two branches (MCU5 and MCU6). A total of 21 pairs of GsMCUs were characterized as duplicated genes, and displayed a similar exon-intron architecture. All GsMCU proteins contained one conserved MCU domain, within which two transmembrane domains were found. An analysis of the conserved motifs further supported that the GsMCUs showed high conservation in protein sequence and structure. Moreover, we found that all GsMCUs were expressed ubiquitously in different tissues and organs, and GsMCUs from the same subgroup displayed varied tissue expression profiles. In addition, based on RNA-seq and qRT-PCR assays, six and nine GsMCUs were differentially expressed under cold and carbonate alkaline stress, respectively. Promoter analysis also uncovered the existence of two canonical cold-related cis-acting elements, LTR and DRE/CRT, as well as stress-related phytohormone-responsive elements. Our results provide valuable information about the MCU family in soybean responses to cold and carbonate alkaline stress, which will be helpful in further characterizing their biological roles in response to abiotic stress.
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Affiliation(s)
- Jianwei Li
- Crop Stress Molecular Biology Laboratory, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Mingzhe Sun
- Crop Stress Molecular Biology Laboratory, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China
- Key Laboratory of Soybean Biology of Chinese Education Ministry, Northeast Agricultural University, Harbin, China
| | - Yu Liu
- Crop Stress Molecular Biology Laboratory, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Xiaoli Sun
- Crop Stress Molecular Biology Laboratory, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Kuide Yin
- Crop Stress Molecular Biology Laboratory, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China
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13
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Watanabe A, Maeda K, Nara A, Hashida M, Ozono M, Nakao A, Yamada A, Shinohara Y, Yamamoto T. Quantitative analysis of mitochondrial calcium uniporter (MCU) and essential MCU regulator (EMRE) in mitochondria from mouse tissues and HeLa cells. FEBS Open Bio 2022; 12:811-826. [PMID: 35060355 PMCID: PMC8972046 DOI: 10.1002/2211-5463.13371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 11/27/2021] [Accepted: 01/19/2022] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial calcium homeostasis plays critical roles in cell survival and aerobic metabolism in eukaryotes. The calcium uniporter is a highly selective calcium ion channel consisting of several subunits. Mitochondrial calcium uniporter (MCU) and essential MCU regulator (EMRE) are core subunits of the calcium uniporter required for calcium uptake activity in the mitochondria. Recent 3D structure analysis of the MCU‐EMRE complex reconstituted in nanodiscs revealed that the human MCU exists as a tetramer forming a channel pore, with EMRE bound to each MCU at a 1 : 1 ratio. However, the stoichiometry of MCU and EMRE in the mitochondria has not yet been investigated. We here quantitatively examined the protein levels of MCU and EMRE in the mitochondria from mouse tissues by using characterized antibodies and standard proteins. Unexpectedly, the number of EMRE molecules was lower than that of MCU; moreover, the ratios between MCU and EMRE were significantly different among tissues. Statistical calculations based on our findings suggest that a MCU tetramer binding to 4 EMREs may exist, but at low levels in the mitochondrial inner membrane. In brain mitochondria, the majority of MCU tetramers bind to 2 EMREs; in mitochondria in liver, kidney, and heart, MCU tetramers bind to 1 EMRE; and in kidney and heart, almost half of MCU tetramers bound to no EMRE. We propose here a novel stoichiometric model of the MCU‐EMRE complex in mitochondria.
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Affiliation(s)
- Akira Watanabe
- Division of Molecular Target and Gene Therapy Products National Institute of Health Sciences 3‐25‐26, Tonomachi, Kawasaki‐ku, Kawasaki‐shi Kanagawa 210‐9501 Japan
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Kousuke Maeda
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Atsushi Nara
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Mei Hashida
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Mizune Ozono
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Ayaka Nakao
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Akiko Yamada
- School of Dentistry Nihon University 1‐8‐13, Kanda‐Surugadai, Chiyoda‐ku Tokyo 101‐8310 Japan
| | - Yasuo Shinohara
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
- Faculty of Pharmaceutical Sciences Tokushima University Shomachi‐1 Tokushima 770‐8505 Japan
| | - Takenori Yamamoto
- Division of Molecular Target and Gene Therapy Products National Institute of Health Sciences 3‐25‐26, Tonomachi, Kawasaki‐ku, Kawasaki‐shi Kanagawa 210‐9501 Japan
- Institute for Genome Research Tokushima University Kuramotocho‐3 Tokushima 770‐8503 Japan
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14
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Abstract
The uptake of calcium into and extrusion of calcium from the mitochondrial matrix is a fundamental biological process that has critical effects on cellular metabolism, signaling, and survival. Disruption of mitochondrial calcium (mCa2+) cycling is implicated in numerous acquired diseases such as heart failure, stroke, neurodegeneration, diabetes, and cancer, and is genetically linked to several inherited neuromuscular disorders. Understanding the mechanisms responsible for mCa2+ exchange therefore holds great promise for the treatment of these diseases. The past decade has seen the genetic identification of many of the key proteins that mediate mitochondrial calcium uptake and efflux. Here, we present an overview of the phenomenon of mCa2+ transport, and a comprehensive examination of the molecular machinery that mediates calcium flux across the inner mitochondrial membrane: the mitochondrial uniporter complex (consisting of MCU, EMRE, MICU1, MICU2, MICU3, MCUB, and MCUR1), NCLX, LETM1, the mitochondrial ryanodine receptor, and the mitochondrial permeability transition pore. We then consider the physiological implications of mCa2+ flux and evaluate how alterations in mCa2+ homeostasis contribute to human disease. This review concludes by highlighting opportunities and challenges for therapeutic intervention in pathologies characterized by aberrant mCa2+ handling and by summarizing critical unanswered questions regarding the biology of mCa2+ flux.
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Affiliation(s)
- Joanne F Garbincius
- Center for Translational Medicine, Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
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15
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Li T, Chen J, Zeng Z. Pathophysiological role of calcium channels and transporters in the multiple myeloma. Cell Commun Signal 2021; 19:99. [PMID: 34579758 PMCID: PMC8477534 DOI: 10.1186/s12964-021-00781-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 08/28/2021] [Indexed: 12/11/2022] Open
Abstract
Multiple myeloma (MM) is a common malignant tumor of plasma cells. Despite several treatment approaches in the past two decades, MM remains an aggressive and incurable disease in dire need of new treatment strategies. Approximately 70–80% of patients with MM have myeloma bone disease (MBD), often accompanied by pathological fractures and hypercalcemia, which seriously affect the prognosis of the patients. Calcium channels and transporters can mediate Ca2+ balance inside and outside of the membrane, indicating that they may be closely related to the prognosis of MM. Therefore, this review focuses on the roles of some critical calcium channels and transporters in MM prognosis, which located in the plasma membrane, endoplasmic reticulum and mitochondria. The goal of this review is to facilitate the identification of new targets for the treatment and prognosis of MM.![]() Video Abstract
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Affiliation(s)
- Tingting Li
- Department of Hematology, The First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou, Fujian, 350005, People's Republic of China.,Fujian Key Laboratory of Laboratory Medicine, Fuzhou, People's Republic of China
| | - Junmin Chen
- Department of Hematology, The First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou, Fujian, 350005, People's Republic of China. .,Fujian Key Laboratory of Laboratory Medicine, Fuzhou, People's Republic of China.
| | - Zhiyong Zeng
- Department of Hematology, The First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou, Fujian, 350005, People's Republic of China. .,Fujian Key Laboratory of Laboratory Medicine, Fuzhou, People's Republic of China.
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16
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Structural characterization of the mitochondrial Ca 2+ uniporter provides insights into Ca 2+ uptake and regulation. iScience 2021; 24:102895. [PMID: 34401674 PMCID: PMC8353469 DOI: 10.1016/j.isci.2021.102895] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The mitochondrial uniporter is a Ca2+-selective ion-conducting channel in the inner mitochondrial membrane that is involved in various cellular processes. The components of this uniporter, including the pore-forming membrane subunit MCU and the modulatory subunits MCUb, EMRE, MICU1, and MICU2, have been identified in recent years. Previously, extensive studies revealed various aspects of uniporter activities and proposed multiple regulatory models of mitochondrial Ca2+ uptake. Recently, the individual auxiliary components of the uniporter and its holocomplex have been structurally characterized, providing the first insight into the component structures and their spatial relationship within the context of the uniporter. Here, we review recent uniporter structural studies in an attempt to establish an architectural framework, elucidating the mechanism that governs mitochondrial Ca2+ uptake and regulation, and to address some apparent controversies. This information could facilitate further characterization of mitochondrial Ca2+ permeation and a better understanding of uniporter-related disease conditions. The uniporter contains multiple subunits regulating various cellular processes Significant structural progresses have been made for the holo-complex of uniporter The holo-complex structures have inspired to propose several regulatory models
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17
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Wang Y, Li X, Zhao F. MCU-Dependent mROS Generation Regulates Cell Metabolism and Cell Death Modulated by the AMPK/PGC-1α/SIRT3 Signaling Pathway. Front Med (Lausanne) 2021; 8:674986. [PMID: 34307407 PMCID: PMC8299052 DOI: 10.3389/fmed.2021.674986] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/14/2021] [Indexed: 11/13/2022] Open
Abstract
The mitochondrial calcium uniporter is an intensively investigated calcium channel, and its molecular components, structural features, and encoded genes have long been explored. Further studies have shown that the mitochondrial calcium unidirectional transporter (MCU) is a macromolecular complex related to intracellular and extracellular calcium regulation. Based on the current understanding, the MCU is crucial for maintaining cytosolic Ca2+ (cCa2+) homeostasis by modulating mitochondrial Ca2+ (mCa2+) uptake. The elevation of MCU-induced calcium levels is confirmed to be the main cause of mitochondrial reactive oxygen species (mROS) generation, which leads to disordered cellular metabolic patterns and cell death. In particular, in an I/R injury model, cancer cells, and adipocytes, MCU expression is maintained at high levels. As is well accepted, the AMPK/PGC-1α/SIRT3 pathway is believed to have an affinity for mROS formation and energy consumption. Therefore, we identified a link between MCU-related mROS formation and the AMPK/PGC-1α/SIRT3 signaling pathway in controlling cell metabolism and cell death, which may provide a new possibility of targeting the MCU to reverse relevant diseases.
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Affiliation(s)
- Yuxin Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiang Li
- Department of Orthopaedic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Fengchao Zhao
- Department of Orthopaedic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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18
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Gherardi G, De Mario A, Mammucari C. The mitochondrial calcium homeostasis orchestra plays its symphony: Skeletal muscle is the guest of honor. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 362:209-259. [PMID: 34253296 DOI: 10.1016/bs.ircmb.2021.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
Skeletal muscle mitochondria are placed in close proximity of the sarcoplasmic reticulum (SR), the main intracellular Ca2+ store. During muscle activity, excitation of sarcolemma and of T-tubule triggers the release of Ca2+ from the SR initiating myofiber contraction. The rise in cytosolic Ca2+ determines the opening of the mitochondrial calcium uniporter (MCU), the highly selective channel of the inner mitochondrial membrane (IMM), causing a robust increase in mitochondrial Ca2+ uptake. The Ca2+-dependent activation of TCA cycle enzymes increases the synthesis of ATP required for SERCA activity. Thus, Ca2+ is transported back into the SR and cytosolic [Ca2+] returns to resting levels eventually leading to muscle relaxation. In recent years, thanks to the molecular identification of MCU complex components, the role of mitochondrial Ca2+ uptake in the pathophysiology of skeletal muscle has been uncovered. In this chapter, we will introduce the reader to a general overview of mitochondrial Ca2+ accumulation. We will tackle the key molecular players and the cellular and pathophysiological consequences of mitochondrial Ca2+ dyshomeostasis. In the second part of the chapter, we will discuss novel findings on the physiological role of mitochondrial Ca2+ uptake in skeletal muscle. Finally, we will examine the involvement of mitochondrial Ca2+ signaling in muscle diseases.
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Affiliation(s)
- Gaia Gherardi
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Agnese De Mario
- Department of Biomedical Sciences, University of Padua, Padua, Italy
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19
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Zhang Y, Yang X, Li Z, Bu K, Li T, Ma Z, Wang B, Ma L, Lu H, Zhang K, Liu L, Zhao Y, Zhu Y, Qin J, Cui J, Liu L, Liu S, Fan P, Liu X. Pyk2/MCU Pathway as a New Target for Reversing Atherosclerosis. Front Cell Dev Biol 2021; 9:651579. [PMID: 34026753 PMCID: PMC8134689 DOI: 10.3389/fcell.2021.651579] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 03/16/2021] [Indexed: 01/08/2023] Open
Abstract
Objective: Multiple mechanisms including vascular endothelial cell damage have a critical role in the formation and development of atherosclerosis (AS), but the specific molecular mechanisms are not exactly clarified. This study aims to determine the possible roles of proline-rich tyrosine kinase 2 (Pyk2)/mitochondrial calcium uniporter (MCU) pathway in AS mouse model and H2O2-induced endothelial cell damage model and explore its possible mechanisms. Approach and Results: The AS mouse model was established using apolipoprotein E-knockout (ApoE–/–) mice that were fed with a high-fat diet. It was very interesting to find that Pyk2/MCU expression was significantly increased in the artery wall of atherosclerotic mice and human umbilical vein endothelial cells (HUVECs) attacked by hydrogen peroxide (H2O2). In addition, down-regulation of Pyk2 by short hairpin RNA (shRNA) protected HUVECs from H2O2 insult. Furthermore, treatment with rosuvastatin on AS mouse model and H2O2-induced HUVEC injury model showed a protective effect against AS by inhibiting the Pyk2/MCU pathway, which maintained calcium balance, prevented the mitochondrial damage and reactive oxygen species production, and eventually inhibited cell apoptosis. Conclusion: Our results provide important insight into the initiation of the Pyk2/MCU pathway involved in AS-related endothelial cell damage, which may be a new promising target for atherosclerosis intervention.
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Affiliation(s)
- Yingzhen Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China.,Department of Basic Medicine, Hebei Medical University, Shijiazhuang, China
| | - Xiaoli Yang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China.,Affiliated Hospital of Hebei University of Engineering, Handan, China
| | - Zhongzhong Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Kailin Bu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Tong Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Zhizhao Ma
- Neurosurgery Department, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Binbin Wang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Lina Ma
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Honglin Lu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Kun Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Luji Liu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Yanying Zhao
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Yipu Zhu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Jin Qin
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Junzhao Cui
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Lin Liu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Shuxia Liu
- Department of Basic Medicine, Hebei Medical University, Shijiazhuang, China
| | - Ping Fan
- Department of Basic Medicine, Hebei Medical University, Shijiazhuang, China
| | - Xiaoyun Liu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China.,Neuroscience Research Center, Medicine and Health Institute, Hebei Medical University, Shijiazhuang, China
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20
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Zhao H, Pan X. Mitochondrial Ca 2+ and cell cycle regulation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 362:171-207. [PMID: 34253295 DOI: 10.1016/bs.ircmb.2021.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It has been demonstrated for more than 40 years that intracellular calcium (Ca2+) controls a variety of cellular functions, including mitochondrial metabolism and cell proliferation. Cytosolic Ca2+ fluctuation during key stages of the cell cycle can lead to mitochondrial Ca2+ uptake and subsequent activation of mitochondrial oxidative phosphorylation and a range of signaling. However, the relationship between mitochondrial Ca2+ and cell cycle progression has long been neglected because the molecule responsible for Ca2+ uptake has been unknown. Recently, the identification of the mitochondrial Ca2+ uniporter (MCU) has led to key advances. With improved Ca2+ imaging and detection, effects of MCU-mediated mitochondrial Ca2+ have been observed at different stages of the cell cycle. Elevated Ca2+ signaling boosts ATP and ROS production, remodels cytosolic Ca2+ pathways and reprograms cell fate-determining networks. These findings suggest that manipulating mitochondrial Ca2+ signaling may serve as a potential strategy in the control of many crucial biological events, such as tumor development and cell division in hematopoietic stem cells (HSCs). In this review, we summarize the current understanding of the role of mitochondrial Ca2+ signaling during different stages of the cell cycle and highlight the potential physiological and pathological significance of mitochondrial Ca2+ signaling.
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Affiliation(s)
- Haixin Zhao
- State Key Laboratory of Experimental Haematology, Institute of Hematology, Fifth Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Xin Pan
- State Key Laboratory of Proteomics, Institute of Basic Medical Sciences, National Center of Biomedical Analysis, Beijing, China.
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21
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Alevriadou BR, Patel A, Noble M, Ghosh S, Gohil VM, Stathopulos PB, Madesh M. Molecular nature and physiological role of the mitochondrial calcium uniporter channel. Am J Physiol Cell Physiol 2021; 320:C465-C482. [PMID: 33296287 PMCID: PMC8260355 DOI: 10.1152/ajpcell.00502.2020] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/23/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023]
Abstract
Calcium (Ca2+) signaling is critical for cell function and cell survival. Mitochondria play a major role in regulating the intracellular Ca2+ concentration ([Ca2+]i). Mitochondrial Ca2+ uptake is an important determinant of cell fate and governs respiration, mitophagy/autophagy, and the mitochondrial pathway of apoptosis. Mitochondrial Ca2+ uptake occurs via the mitochondrial Ca2+ uniporter (MCU) complex. This review summarizes the present knowledge on the function of MCU complex, regulation of MCU channel, and the role of MCU in Ca2+ homeostasis and human disease pathogenesis. The channel core consists of four MCU subunits and essential MCU regulators (EMRE). Regulatory proteins that interact with them include mitochondrial Ca2+ uptake 1/2 (MICU1/2), MCU dominant-negative β-subunit (MCUb), MCU regulator 1 (MCUR1), and solute carrier 25A23 (SLC25A23). In addition to these proteins, cardiolipin, a mitochondrial membrane-specific phospholipid, has been shown to interact with the channel core. The dynamic interplay between the core and regulatory proteins modulates MCU channel activity after sensing local changes in [Ca2+]i, reactive oxygen species, and other environmental factors. Here, we highlight the structural details of the human MCU heteromeric assemblies and their known roles in regulating mitochondrial Ca2+ homeostasis. MCU dysfunction has been shown to alter mitochondrial Ca2+ dynamics, in turn eliciting cell apoptosis. Changes in mitochondrial Ca2+ uptake have been implicated in pathological conditions affecting multiple organs, including the heart, skeletal muscle, and brain. However, our structural and functional knowledge of this vital protein complex remains incomplete, and understanding the precise role for MCU-mediated mitochondrial Ca2+ signaling in disease requires further research efforts.
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Affiliation(s)
- B Rita Alevriadou
- Department of Biomedical Engineering, Jacobs School of Medicine and Biomedical Sciences and School of Engineering and Applied Sciences, University at Buffalo-State University of New York, Buffalo, New York
| | - Akshar Patel
- Department of Biomedical Engineering, Jacobs School of Medicine and Biomedical Sciences and School of Engineering and Applied Sciences, University at Buffalo-State University of New York, Buffalo, New York
| | - Megan Noble
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Sagnika Ghosh
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas
| | - Vishal M Gohil
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Muniswamy Madesh
- Department of Medicine/Cardiology Division, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, Texas
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22
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Mitochondrial Calcium Signaling in Pancreatic β-Cell. Int J Mol Sci 2021; 22:ijms22052515. [PMID: 33802289 PMCID: PMC7959128 DOI: 10.3390/ijms22052515] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/22/2021] [Accepted: 02/26/2021] [Indexed: 12/13/2022] Open
Abstract
Accumulation of calcium in energized mitochondria of pancreatic β-cells is emerging as a crucial process for pancreatic β-cell function. β-cell mitochondria sense and shape calcium signals, linking the metabolism of glucose and other secretagogues to the generation of signals that promote insulin secretion during nutrient stimulation. Here, we describe the role of mitochondrial calcium signaling in pancreatic β-cell function. We report the latest pharmacological and genetic findings, including the first mitochondrial calcium-targeted intervention strategies developed to modulate pancreatic β-cell function and their potential relevance in the context of diabetes.
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23
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Feno S, Rizzuto R, Raffaello A, Vecellio Reane D. The molecular complexity of the Mitochondrial Calcium Uniporter. Cell Calcium 2020; 93:102322. [PMID: 33264708 DOI: 10.1016/j.ceca.2020.102322] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 12/20/2022]
Abstract
The role of mitochondria in regulating cellular Ca2+ homeostasis is crucial for the understanding of different cellular functions in physiological and pathological conditions. Nevertheless, the study of this aspect was severely limited by the lack of the molecular identity of the proteins responsible for mitochondrial Ca2+ uptake. In 2011, the discovery of the gene encoding for the Mitochondrial Calcium Uniporter (MCU), the selective channel responsible for mitochondrial Ca2+ uptake, gave rise to an explosion of studies aimed to characterize the composition, the regulation of the channel and its pathophysiological roles. Here, we summarize the recent discoveries on the molecular structure and composition of the MCU complex by providing new insights into the mechanisms that regulate MCU channel activity.
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Affiliation(s)
- Simona Feno
- Department of Biomedical Science, University of Padua, via G. Colombo 3, 35100 Padua, Italy
| | - Rosario Rizzuto
- Department of Biomedical Science, University of Padua, via G. Colombo 3, 35100 Padua, Italy
| | - Anna Raffaello
- Department of Biomedical Science, University of Padua, via G. Colombo 3, 35100 Padua, Italy; Myology Center, University of Padua, via G. Colombo 3, 35100 Padova, Italy.
| | - Denis Vecellio Reane
- Department of Biomedical Science, University of Padua, via G. Colombo 3, 35100 Padua, Italy.
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24
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MacEwen MJ, Markhard AL, Bozbeyoglu M, Bradford F, Goldberger O, Mootha VK, Sancak Y. Evolutionary divergence reveals the molecular basis of EMRE dependence of the human MCU. Life Sci Alliance 2020; 3:e202000718. [PMID: 32769116 PMCID: PMC7425227 DOI: 10.26508/lsa.202000718] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 07/28/2020] [Accepted: 07/29/2020] [Indexed: 01/18/2023] Open
Abstract
The mitochondrial calcium uniporter (MCU) is a calcium-activated calcium channel critical for signaling and bioenergetics. MCU, the pore-forming subunit of the uniporter, contains two transmembrane domains and is found in all major eukaryotic taxa. In amoeba and fungi, MCU homologs are sufficient to form a functional calcium channel, whereas human MCU exhibits a strict requirement for the metazoan protein essential MCU regulator (EMRE) for conductance. Here, we exploit this evolutionary divergence to decipher the molecular basis of human MCU's dependence on EMRE. By systematically generating chimeric proteins that consist of EMRE-independent Dictyostelium discoideum MCU and Homo sapiens MCU (HsMCU), we converged on a stretch of 10 amino acids in D. discoideum MCU that can be transplanted to HsMCU to render it EMRE independent. We call this region in human MCU the EMRE dependence domain (EDD). Crosslinking experiments show that EMRE directly interacts with HsMCU at its transmembrane domains as well as the EDD. Our results suggest that EMRE stabilizes the EDD of MCU, permitting both channel opening and calcium conductance, consistent with recently published structures of MCU-EMRE.
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Affiliation(s)
| | - Andrew L Markhard
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Mert Bozbeyoglu
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Forrest Bradford
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - Olga Goldberger
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Vamsi K Mootha
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
- Broad Institute, Cambridge, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Yasemin Sancak
- Department of Pharmacology, University of Washington, Seattle, WA, USA
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25
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Wang C, Baradaran R, Long SB. Structure and Reconstitution of an MCU-EMRE Mitochondrial Ca 2+ Uniporter Complex. J Mol Biol 2020; 432:5632-5648. [PMID: 32841658 PMCID: PMC7577567 DOI: 10.1016/j.jmb.2020.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/15/2020] [Accepted: 08/18/2020] [Indexed: 10/23/2022]
Abstract
The proteins MCU and EMRE form the minimal functional unit of the mitochondrial calcium uniporter complex in metazoans, a highly selective and tightly controlled Ca2+ channel of the inner mitochondrial membrane that regulates cellular metabolism. Here we present functional reconstitution of an MCU-EMRE complex from the red flour beetle, Tribolium castaneum, and a cryo-EM structure of the complex at 3.5 Å resolution. Using a novel assay, we demonstrate robust Ca2+ uptake into proteoliposomes containing the purified complex. Uptake is dependent on EMRE and also on the mitochondrial lipid cardiolipin. The structure reveals a tetrameric channel with a single ion pore. EMRE is located at the periphery of the transmembrane domain and associates primarily with the first transmembrane helix of MCU. Coiled-coil and juxtamembrane domains within the matrix portion of the complex adopt markedly different conformations than in a structure of a human MCU-EMRE complex, suggesting that the structures represent different conformations of these functionally similar metazoan channels.
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Affiliation(s)
- Chongyuan Wang
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Rozbeh Baradaran
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Stephen Barstow Long
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
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Carvalho EJ, Stathopulos PB, Madesh M. Regulation of Ca 2+ exchanges and signaling in mitochondria. CURRENT OPINION IN PHYSIOLOGY 2020; 17:197-206. [PMID: 33103015 DOI: 10.1016/j.cophys.2020.08.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Mitochondrial calcium (mCa2+) homeostasis also plays a key role in the buffering of cytosolic calcium (cCa2+) and calcium transported into the mitochondrial matrix regulates cellular metabolism, migration and cell fate decisions. Recent work has highlighted the importance of mCa2+ homeostasis in regulating cellular function. The discovery of the mCa2+ uptake complex has shed new light on the role of mCa2+ dynamics in cytoskeletal remodeling, mitochondrial shape and motility in cellular dynamics. Here we attempt to decipher the vast landscape of calcium regulatory effects of the mitochondria, the underlying mechanisms and the dynamics that control cellular function.
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Affiliation(s)
- Edmund J Carvalho
- Department of Medicine, Centre for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX, 78228.,Department of Microbiology, Centre for Cellular Immunotherapies, University of Pennsylvania, Pennsylvania, 19104
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Western University, London, ON N6A 5C1, Canada
| | - Muniswamy Madesh
- Department of Medicine, Centre for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX, 78228
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27
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Lee Y, Park J, Lee G, Yoon S, Min CK, Kim TG, Yamamoto T, Kim DH, Lee KW, Eom SH. S92 phosphorylation induces structural changes in the N-terminus domain of human mitochondrial calcium uniporter. Sci Rep 2020; 10:9131. [PMID: 32499574 PMCID: PMC7272466 DOI: 10.1038/s41598-020-65994-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 05/08/2020] [Indexed: 01/07/2023] Open
Abstract
The mitochondrial calcium uniporter (MCU) plays essential roles in mitochondrial calcium homeostasis and regulates cellular functions, such as energy synthesis, cell growth, and development. Thus, MCU activity is tightly controlled by its regulators as well as post-translational modification, including phosphorylation by protein kinases such as proline-rich tyrosine kinase 2 (Pyk2) and AMP-activated protein kinase (AMPK). In our in vitro kinase assay, the MCU N-terminal domain (NTD) was phosphorylated by protein kinase C isoforms (PKCβII, PKCδ, and PKCε) localized in the mitochondrial matrix. In addition, we found the conserved S92 was phosphorylated by the PKC isoforms. To reveal the structural effect of MCU S92 phosphorylation (S92p), we determined crystal structures of the MCU NTD of S92E and D119A mutants and analysed the molecular dynamics simulation of WT and S92p. We observed conformational changes of the conserved loop2-loop4 (L2-L4 loops) in MCU NTDS92E, NTDD119A, and NTDS92p due to the breakage of the S92-D119 hydrogen bond. The results suggest that the phosphorylation of S92 induces conformational changes as well as enhancements of the negative charges at the L2-L4 loops, which may affect the dimerization of two MCU-EMRE tetramers.
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Affiliation(s)
- Youngjin Lee
- 0000 0001 1033 9831grid.61221.36School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0001 1033 9831grid.61221.36Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0004 0636 3099grid.249967.7Infection and Immunity Research Laboratory, Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141 Republic of Korea
| | - Jongseo Park
- 0000 0001 1033 9831grid.61221.36School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0001 1033 9831grid.61221.36Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea
| | - Gihwan Lee
- 0000 0001 0661 1492grid.256681.eDivision of Life Science, Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center (PMBBRC), Research Institute of Natural Science (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju, 52828 Republic of Korea
| | - Sanghwa Yoon
- 0000 0001 0661 1492grid.256681.eDivision of Life Science, Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center (PMBBRC), Research Institute of Natural Science (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju, 52828 Republic of Korea
| | - Choon Kee Min
- 0000 0001 1033 9831grid.61221.36School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0001 1033 9831grid.61221.36Systems Biology Research Center, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea
| | - Tae Gyun Kim
- 0000 0001 1033 9831grid.61221.36School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0001 1033 9831grid.61221.36Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0000 9805 2626grid.250464.1Present Address: Molecular Cryo-Electron Microscopy Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna, Kunigami 904-0495 Japan
| | - Takenori Yamamoto
- 0000 0001 1092 3579grid.267335.6Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima, 770-8503 Japan ,0000 0001 1092 3579grid.267335.6Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima, 770-8505 Japan
| | - Do Han Kim
- 0000 0001 1033 9831grid.61221.36School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0001 1033 9831grid.61221.36Systems Biology Research Center, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea
| | - Keun Woo Lee
- 0000 0001 0661 1492grid.256681.eDivision of Life Science, Division of Applied Life Science (BK21 Plus), Plant Molecular Biology and Biotechnology Research Center (PMBBRC), Research Institute of Natural Science (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju, 52828 Republic of Korea
| | - Soo Hyun Eom
- 0000 0001 1033 9831grid.61221.36School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea ,0000 0001 1033 9831grid.61221.36Steitz Center for Structural Biology, Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju 61005 Republic of Korea
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28
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Liu JC. Is MCU dispensable for normal heart function? J Mol Cell Cardiol 2020; 143:175-183. [DOI: 10.1016/j.yjmcc.2020.04.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/07/2020] [Accepted: 04/24/2020] [Indexed: 12/14/2022]
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Noble M, Lin QT, Sirko C, Houpt JA, Novello MJ, Stathopulos PB. Structural Mechanisms of Store-Operated and Mitochondrial Calcium Regulation: Initiation Points for Drug Discovery. Int J Mol Sci 2020; 21:E3642. [PMID: 32455637 PMCID: PMC7279490 DOI: 10.3390/ijms21103642] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/11/2020] [Accepted: 05/17/2020] [Indexed: 12/18/2022] Open
Abstract
Calcium (Ca2+) is a universal signaling ion that is essential for the life and death processes of all eukaryotes. In humans, numerous cell stimulation pathways lead to the mobilization of sarco/endoplasmic reticulum (S/ER) stored Ca2+, resulting in the propagation of Ca2+ signals through the activation of processes, such as store-operated Ca2+ entry (SOCE). SOCE provides a sustained Ca2+ entry into the cytosol; moreover, the uptake of SOCE-mediated Ca2+ by mitochondria can shape cytosolic Ca2+ signals, function as a feedback signal for the SOCE molecular machinery, and drive numerous mitochondrial processes, including adenosine triphosphate (ATP) production and distinct cell death pathways. In recent years, tremendous progress has been made in identifying the proteins mediating these signaling pathways and elucidating molecular structures, invaluable for understanding the underlying mechanisms of function. Nevertheless, there remains a disconnect between using this accumulating protein structural knowledge and the design of new research tools and therapies. In this review, we provide an overview of the Ca2+ signaling pathways that are involved in mediating S/ER stored Ca2+ release, SOCE, and mitochondrial Ca2+ uptake, as well as pinpoint multiple levels of crosstalk between these pathways. Further, we highlight the significant protein structures elucidated in recent years controlling these Ca2+ signaling pathways. Finally, we describe a simple strategy that aimed at applying the protein structural data to initiating drug design.
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Affiliation(s)
- Megan Noble
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Qi-Tong Lin
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Christian Sirko
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Jacob A. Houpt
- Department of Medicine, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada;
| | - Matthew J. Novello
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
| | - Peter B. Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON N6A5C1, Canada; (M.N.); (Q.-T.L.); (C.S.); (M.J.N.)
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30
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Barger JP, Dillon PF. Electrophoretic measurement of water charge density and ion hydration. Electrophoresis 2020; 41:1170-1177. [PMID: 32357247 DOI: 10.1002/elps.201900467] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 11/07/2022]
Abstract
Water exchange between bulk water and water-ion complexes will be at equilibrium when the charge density of the complex surface equals the charge density of bulk water, producing a constant radius water-ion complex. This complex will migrate in an electric field at a velocity proportional to the complex radius. CE velocity is the sum of the complex charge-dependent velocity and the buffer electro-osmotic flow. Simultaneous use of both a base (1.07 mM imidazole) and an acid (1.5 mM MOPS) buffer negates EOF at pH 7.4. Electric fields below 300 V/cm (potassium, calcium) and 400 V/cm (magnesium) yield migration velocities with no dehydration of the water-ion complexes. The number of waters per complex increase with the ion charge density: K+ 1.90, Ca++ 5.90, Mg++ 6.59 waters/ion. The charge densities of the complexes are similar: K+ 1.24, Ca++ 1.43, Mg++ 1.21 e/nm2 , for an average bulk water charge density of 1.29 ± 0.11 (SD) e/nm2 . The addition of 0.1% Triton increases the number of waters for Mg++ to 25.33 and lowers the charge density to 0.497 e/nm2 . High electric field dehydration shows that calcium will be fully dehydrated at 638.3 V/cm and magnesium fully dehydrated at 925.5 V/cm, which occur at 6.15 and 5.78 nm from the membrane. Dehydrated magnesium will then bind to calcium channels leading to decreased smooth muscle activation.
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Affiliation(s)
- James P Barger
- Department of Physiology, Michigan State University, East Lansing, MI
| | - Patrick F Dillon
- Department of Physiology, Michigan State University, East Lansing, MI
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31
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Woods JJ, Lovett J, Lai B, Harris HH, Wilson JJ. Redox Stability Controls the Cellular Uptake and Activity of Ruthenium‐Based Inhibitors of the Mitochondrial Calcium Uniporter (MCU). Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000247] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Joshua J. Woods
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
- Robert F. Smith School for Chemical and Biomolecular Engineering Cornell University Ithaca NY 14853 USA
| | - James Lovett
- Department of Chemistry The University of Adelaide Adelaide SA 5005 Australia
| | - Barry Lai
- Advanced Photon Source X-ray Science Division Argonne National Laboratory Argonne IL 60439 USA
| | - Hugh H. Harris
- Department of Chemistry The University of Adelaide Adelaide SA 5005 Australia
| | - Justin J. Wilson
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
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32
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Yuan Y, Cao C, Wen M, Li M, Dong Y, Wu L, Wu J, Cui T, Li D, Chou JJ, OuYang B. Structural Characterization of the N-Terminal Domain of the Dictyostelium discoideum Mitochondrial Calcium Uniporter. ACS OMEGA 2020; 5:6452-6460. [PMID: 32258880 PMCID: PMC7114133 DOI: 10.1021/acsomega.9b04045] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/20/2020] [Indexed: 06/11/2023]
Abstract
The mitochondrial calcium uniporter (MCU) plays a critical role in mitochondrial calcium uptake into the matrix. In metazoans, the uniporter is a tightly regulated multicomponent system, including the pore-forming subunit MCU and several regulators (MICU1, MICU2, and Essential MCU REgulator, EMRE). The calcium-conducting activity of metazoan MCU requires the single-transmembrane protein EMRE. Dictyostelium discoideum (Dd), however, developed a simplified uniporter for which the pore-forming MCU (DdMCU) alone is necessary and sufficient for calcium influx. Here, we report a crystal structure of the N-terminal domain (NTD) of DdMCU at 1.7 Å resolution. The DdMCU-NTD contains four helices and two strands arranged in a fold that is completely different from the known structures of other MCU-NTD homologues. Biochemical and biophysical analyses of DdMCU-NTD in solution indicated that the domain exists as high-order oligomers. Mutagenesis showed that the acidic residues Asp60, Glu72, and Glu74, which appeared to mediate the interface II, as observed in the crystal structure, participated in the self-assembly of DdMCU-NTD. Intriguingly, the oligomeric complex was disrupted in the presence of calcium. We propose that the calcium-triggered dissociation of NTD regulates the channel activity of DdMCU by a yet unknown mechanism.
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Affiliation(s)
- Yuan Yuan
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - Chan Cao
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - Maorong Wen
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - Min Li
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - Ying Dong
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - Lijie Wu
- Shanghai Institute for Advanced Immunochemical
Studies and iHuman Institute, ShanghaiTech
University, Shanghai 201210, China
| | - Jian Wu
- Ninth People’s
Hospital, Shanghai Jiao Tong University
School of Medicine, Shanghai 200125, China
| | - Tanxing Cui
- Department of Biological
Chemistry and Molecular Pharmacology, Harvard
Medical School, Boston, Massachusetts 02115, United States
| | - Dianfan Li
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - James J. Chou
- Department of Biological
Chemistry and Molecular Pharmacology, Harvard
Medical School, Boston, Massachusetts 02115, United States
| | - Bo OuYang
- State Key Laboratory
of Molecular Biology, CAS Center for Excellence in Molecular Cell
Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese
Academy of Sciences, University of Chinese
Academy of Sciences, 333 Haike Road, Shanghai 201203, China
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33
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Woods JJ, Lovett J, Lai B, Harris HH, Wilson JJ. Redox Stability Controls the Cellular Uptake and Activity of Ruthenium‐Based Inhibitors of the Mitochondrial Calcium Uniporter (MCU). Angew Chem Int Ed Engl 2020; 59:6482-6491. [DOI: 10.1002/anie.202000247] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Joshua J. Woods
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
- Robert F. Smith School for Chemical and Biomolecular Engineering Cornell University Ithaca NY 14853 USA
| | - James Lovett
- Department of Chemistry The University of Adelaide Adelaide SA 5005 Australia
| | - Barry Lai
- Advanced Photon Source X-ray Science Division Argonne National Laboratory Argonne IL 60439 USA
| | - Hugh H. Harris
- Department of Chemistry The University of Adelaide Adelaide SA 5005 Australia
| | - Justin J. Wilson
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
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Navazio L, Formentin E, Cendron L, Szabò I. Chloroplast Calcium Signaling in the Spotlight. FRONTIERS IN PLANT SCIENCE 2020; 11:186. [PMID: 32226434 PMCID: PMC7081724 DOI: 10.3389/fpls.2020.00186] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 02/07/2020] [Indexed: 05/22/2023]
Abstract
Calcium has long been known to regulate the metabolism of chloroplasts, concerning both light and carbon reactions of photosynthesis, as well as additional non photosynthesis-related processes. In addition to undergo Ca2+ regulation, chloroplasts can also influence the overall Ca2+ signaling pathways of the plant cell. Compelling evidence indicate that chloroplasts can generate specific stromal Ca2+ signals and contribute to the fine tuning of cytoplasmic Ca2+ signaling in response to different environmental stimuli. The recent set up of a toolkit of genetically encoded Ca2+ indicators, targeted to different chloroplast subcompartments (envelope, stroma, thylakoids) has helped to unravel the participation of chloroplasts in intracellular Ca2+ handling in resting conditions and during signal transduction. Intra-chloroplast Ca2+ signals have been demonstrated to occur in response to specific environmental stimuli, suggesting a role for these plant-unique organelles in transducing Ca2+-mediated stress signals. In this mini-review we present current knowledge of stimulus-specific intra-chloroplast Ca2+ transients, as well as recent advances in the identification and characterization of Ca2+-permeable channels/transporters localized at chloroplast membranes. In particular, the potential role played by cMCU, a chloroplast-localized member of the mitochondrial calcium uniporter (MCU) family, as component of plant environmental sensing is discussed in detail, taking into account some specific structural features of cMCU. In summary, the recent molecular identification of some players of chloroplast Ca2+ signaling has opened new avenues in this rapidly developing field and will hopefully allow a deeper understanding of the role of chloroplasts in shaping physiological responses in plants.
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Affiliation(s)
- Lorella Navazio
- Department of Biology, University of Padova, Padova, Italy
- Botanical Garden, University of Padova, Padova, Italy
| | - Elide Formentin
- Department of Biology, University of Padova, Padova, Italy
- Botanical Garden, University of Padova, Padova, Italy
| | - Laura Cendron
- Department of Biology, University of Padova, Padova, Italy
| | - Ildikò Szabò
- Department of Biology, University of Padova, Padova, Italy
- Botanical Garden, University of Padova, Padova, Italy
- *Correspondence: Ildikò Szabò,
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35
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Woods JJ, Wilson JJ. Inhibitors of the mitochondrial calcium uniporter for the treatment of disease. Curr Opin Chem Biol 2019; 55:9-18. [PMID: 31869674 DOI: 10.1016/j.cbpa.2019.11.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 11/12/2019] [Accepted: 11/15/2019] [Indexed: 01/04/2023]
Abstract
The mitochondrial calcium uniporter (MCU) is a protein located in the inner mitochondrial membrane that is responsible for mitochondrial Ca2+ uptake. Under certain pathological conditions, dysregulation of Ca2+ uptake through the MCU results in cellular dysfunction and apoptotic cell death. Given the role of the MCU in human disease, researchers have developed compounds capable of inhibiting mitochondrial calcium uptake as tools for understanding the role of this protein in cell death. In this article, we describe recent findings on the role of the MCU in mediating pathological conditions and the search for small-molecule inhibitors of this protein for potential therapeutic applications.
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Affiliation(s)
- Joshua J Woods
- Robert F. Smith School for Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA; Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14583, USA
| | - Justin J Wilson
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14583, USA.
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36
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Tarasova NV, Vishnyakova PA, Logashina YA, Elchaninov AV. Mitochondrial Calcium Uniporter Structure and Function in Different Types of Muscle Tissues in Health and Disease. Int J Mol Sci 2019; 20:ijms20194823. [PMID: 31569359 PMCID: PMC6801532 DOI: 10.3390/ijms20194823] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/12/2019] [Accepted: 09/26/2019] [Indexed: 02/07/2023] Open
Abstract
Calcium ions (Ca2+) influx to mitochondrial matrix is crucial for the life of a cell. Mitochondrial calcium uniporter (mtCU) is a protein complex which consists of the pore-forming subunit (MCU) and several regulatory subunits. MtCU is the main contributor to inward Ca2+ currents through the inner mitochondrial membrane. Extensive investigations of mtCU involvement into normal and pathological molecular pathways started from the moment of discovery of its molecular components. A crucial role of mtCU in the control of these pathways is now recognized in both health and disease. In particular, impairments of mtCU function have been demonstrated for cardiovascular and skeletal muscle-associated pathologies. This review summarizes the current state of knowledge on mtCU structure, regulation, and function in different types of muscle tissues in health and disease.
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Affiliation(s)
- Nadezhda V Tarasova
- Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Trubetskaya str. 8, bld. 2, Moscow 119991, Russia.
| | - Polina A Vishnyakova
- National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 4 Oparina Street, Moscow 117997, Russia.
| | - Yulia A Logashina
- Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Trubetskaya str. 8, bld. 2, Moscow 119991, Russia.
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street 16/10, Moscow 117997, Russia.
| | - Andrey V Elchaninov
- National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, 4 Oparina Street, Moscow 117997, Russia.
- Scientific Research Institute of Human Morphology, 3 Tsurupa Street, Moscow 117418, Russia.
- Peoples' Friendship University of Russia, 6 Miklukho-Maklaya Street, Moscow 117198, Russia.
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37
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Wu L, Tan JL, Chen ZY, Huang G. Cardioprotection of post-ischemic moderate ROS against ischemia/reperfusion via STAT3-induced the inhibition of MCU opening. Basic Res Cardiol 2019; 114:39. [DOI: 10.1007/s00395-019-0747-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 08/19/2019] [Indexed: 12/20/2022]
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38
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Yamamoto T, Ozono M, Watanabe A, Maeda K, Nara A, Hashida M, Ido Y, Hiroshima Y, Yamada A, Terada H, Shinohara Y. Functional analysis of coiled-coil domains of MCU in mitochondrial calcium uptake. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:148061. [PMID: 31394096 DOI: 10.1016/j.bbabio.2019.148061] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 07/20/2019] [Accepted: 08/02/2019] [Indexed: 11/30/2022]
Abstract
The mitochondrial calcium uniporter (MCU) complex is a highly-selective calcium channel. This complex consists of MCU, mitochondrial calcium uptake proteins (MICUs), MCU regulator 1 (MCUR1), essential MCU regulator element (EMRE), etc. MCU, which is the pore-forming subunit, has 2 highly conserved coiled-coil domains (CC1 and CC2); however, their functional roles are unknown. The yeast expression system of mammalian MCU and EMRE enables precise reconstitution of the properties of the mammalian MCU complex in yeast mitochondria. Using the yeast expression system, we here showed that, when MCU mutant lacking CC1 or CC2 was expressed together with EMRE in yeast, their mitochondrial Ca2+-uptake function was lost. Additionally, point mutations in CC1 or CC2, which were expected to prevent the formation of the coiled coil, also disrupted the Ca2+-uptake function. Thus, it is essential for the Ca2+ uptake function of MCU that the coiled-coil structure be formed in CC1 and CC2. The loss of function of those mutated MCUs was also observed in the mitochondria of a yeast strain lacking the yeast MCUR1 homolog. Also, in the D. discoideum MCU, which has EMRE-independent Ca2+-uptake function, the deletion of either CC1 or CC2 caused the loss of function. These results indicated that the critical functions of CC1 and CC2 were independent of other regulatory subunits such as MCUR1 and EMRE, suggesting that CC1 and CC2 might be essential for pore formation by MCUs themselves. Based on the tetrameric structure of MCU, we discussed the functional roles of the coiled-coil domains of MCU.
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Affiliation(s)
- Takenori Yamamoto
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan.
| | - Mizune Ozono
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan
| | - Akira Watanabe
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan
| | - Kosuke Maeda
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan
| | - Atsushi Nara
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan
| | - Mei Hashida
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan
| | - Yusuke Ido
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan
| | - Yuka Hiroshima
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan
| | - Akiko Yamada
- School of Dentistry, Tokushima University, Kuramotocho-3, Tokushima 770-8504, Japan
| | - Hiroshi Terada
- Niigata University of Pharmacy and Applied Life Sciences, Niigata City 956-8603, Japan
| | - Yasuo Shinohara
- Institute for Genome Research, Tokushima University, Kuramotocho-3, Tokushima 770-8503, Japan; Faculty of Pharmaceutical Sciences, Tokushima University, Shomachi-1, Tokushima 770-8505, Japan.
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39
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Wang Y, Nguyen NX, She J, Zeng W, Yang Y, Bai XC, Jiang Y. Structural Mechanism of EMRE-Dependent Gating of the Human Mitochondrial Calcium Uniporter. Cell 2019; 177:1252-1261.e13. [PMID: 31080062 DOI: 10.1016/j.cell.2019.03.050] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 02/09/2019] [Accepted: 03/27/2019] [Indexed: 01/06/2023]
Abstract
Mitochondrial calcium uptake is crucial to the regulation of eukaryotic Ca2+ homeostasis and is mediated by the mitochondrial calcium uniporter (MCU). While MCU alone can transport Ca2+ in primitive eukaryotes, metazoans require an essential single membrane-spanning auxiliary component called EMRE to form functional channels; however, the molecular mechanism of EMRE regulation remains elusive. Here, we present the cryo-EM structure of the human MCU-EMRE complex, which defines the interactions between MCU and EMRE as well as pinpoints the juxtamembrane loop of MCU and extended linker of EMRE as the crucial elements in the EMRE-dependent gating mechanism among metazoan MCUs. The structure also features the dimerization of two MCU-EMRE complexes along an interface at the N-terminal domain (NTD) of human MCU that is a hotspot for post-translational modifications. Thus, the human MCU-EMRE complex, which constitutes the minimal channel components among metazoans, provides a framework for future mechanistic studies on MCU.
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Affiliation(s)
- Yan Wang
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Nam X Nguyen
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ji She
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Weizhong Zeng
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yi Yang
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Xiao-Chen Bai
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Youxing Jiang
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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40
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Crosstalk between Calcium and ROS in Pathophysiological Conditions. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:9324018. [PMID: 31178978 PMCID: PMC6507098 DOI: 10.1155/2019/9324018] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 04/01/2019] [Indexed: 12/12/2022]
Abstract
Calcium ions are highly versatile intracellular signals that regulate many cellular processes. The key to achieving this pleiotropic role is the spatiotemporal control of calcium concentration evoked by an extensive molecular repertoire of signalling components. Among these, reactive oxygen species (ROS) signalling, together with calcium signalling, plays a crucial role in controlling several physiopathological events. Although initially considered detrimental by-products of aerobic metabolism, it is now widely accepted that ROS, in subtoxic levels, act as signalling molecules. However, dysfunctions in the mechanisms controlling the physiological ROS concentration affect cellular homeostasis, leading to the pathogenesis of various disorders.
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41
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Woods J, Nemani N, Shanmughapriya S, Kumar A, Zhang M, Nathan SR, Thomas M, Carvalho E, Ramachandran K, Srikantan S, Stathopulos PB, Wilson JJ, Madesh M. A Selective and Cell-Permeable Mitochondrial Calcium Uniporter (MCU) Inhibitor Preserves Mitochondrial Bioenergetics after Hypoxia/Reoxygenation Injury. ACS CENTRAL SCIENCE 2019; 5:153-166. [PMID: 30693334 PMCID: PMC6346394 DOI: 10.1021/acscentsci.8b00773] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Indexed: 05/10/2023]
Abstract
Mitochondrial Ca2+ (mCa2+) uptake mediated by the mitochondrial calcium uniporter (MCU) plays a critical role in signal transduction, bioenergetics, and cell death, and its dysregulation is linked to several human diseases. In this study, we report a new ruthenium complex Ru265 that is cell-permeable, minimally toxic, and highly potent with respect to MCU inhibition. Cells treated with Ru265 show inhibited MCU activity without any effect on cytosolic Ca2+ dynamics and mitochondrial membrane potential (ΔΨm). Dose-dependent studies reveal that Ru265 is more potent than the currently employed MCU inhibitor Ru360. Site-directed mutagenesis of Cys97 in the N-terminal domain of human MCU ablates the inhibitory activity of Ru265, suggesting that this matrix-residing domain is its target site. Additionally, Ru265 prevented hypoxia/reoxygenation injury and subsequent mitochondrial dysfunction, demonstrating that this new inhibitor is a valuable tool for studying the functional role of the MCU in intact biological models.
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Affiliation(s)
- Joshua
J. Woods
- Robert
F. Smith School for Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, United States
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Neeharika Nemani
- Department
of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Center
for Translational Medicine, Lewis Katz School
of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Santhanam Shanmughapriya
- Department
of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Center
for Translational Medicine, Lewis Katz School
of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Akshay Kumar
- Department
of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Center
for Translational Medicine, Lewis Katz School
of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - MengQi Zhang
- Department
of Physiology and Pharmacology, Western
University, London, Ontario N6A 5C1, Canada
| | - Sarah R. Nathan
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Manfred Thomas
- Department
of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Center
for Translational Medicine, Lewis Katz School
of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Edmund Carvalho
- Department
of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Center
for Translational Medicine, Lewis Katz School
of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Karthik Ramachandran
- Department
of Medicine/Nephrology, Institute for Precision Medicine and Health, University of Texas Health San Antonio, San Antonio, Texas 78229, United States
| | - Subramanya Srikantan
- Department
of Medicine/Nephrology, Institute for Precision Medicine and Health, University of Texas Health San Antonio, San Antonio, Texas 78229, United States
| | - Peter B. Stathopulos
- Department
of Physiology and Pharmacology, Western
University, London, Ontario N6A 5C1, Canada
| | - Justin J. Wilson
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Muniswamy Madesh
- Department
of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Center
for Translational Medicine, Lewis Katz School
of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
- Department
of Medicine/Nephrology, Institute for Precision Medicine and Health, University of Texas Health San Antonio, San Antonio, Texas 78229, United States
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42
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Characterization of MCU-Binding Proteins MCUR1 and CCDC90B - Representatives of a Protein Family Conserved in Prokaryotes and Eukaryotic Organelles. Structure 2019; 27:464-475.e6. [PMID: 30612859 DOI: 10.1016/j.str.2018.11.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 10/12/2018] [Accepted: 11/06/2018] [Indexed: 12/14/2022]
Abstract
Membrane-bound coiled-coil proteins are important mediators of signaling, fusion, and scaffolding. Here, we delineate a heterogeneous group of trimeric membrane-anchored proteins in prokaryotes and eukaryotic organelles with a characteristic head-neck-stalk-anchor architecture, in which a membrane-anchored coiled-coil stalk projects an N-terminal head domain via a β-layer neck. Based on sequence analysis, we identify different types of head domains and determine crystal structures of two representatives, the archaeal protein Kcr-0859 and the human CCDC90B, which possesses the most widespread head type. Using mitochondrial calcium uniporter regulator 1 (MCUR1), the functionally characterized paralog of CCDC90B, we study the role of individual domains, and find that the head interacts directly with the mitochondrial calcium uniporter (MCU) and is destabilized upon Ca2+ binding. Our data provide structural details of a class of membrane-bound coiled-coil proteins and identify the conserved head domain of the most widespread type as a mediator of their function.
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43
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Wang P, Fernandez-Sanz C, Wang W, Sheu SS. Why don't mice lacking the mitochondrial Ca 2+ uniporter experience an energy crisis? J Physiol 2018; 598:1307-1326. [PMID: 30218574 DOI: 10.1113/jp276636] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/28/2018] [Indexed: 01/15/2023] Open
Abstract
Current dogma holds that the heart balances energy demand and supply effectively and sustainably by sequestering enough Ca2+ into mitochondria during heartbeats to stimulate metabolic enzymes in the tricarboxylic acid (TCA) cycle and electron transport chain (ETC). This process is called excitation-contraction-bioenergetics (ECB) coupling. Recent breakthroughs in identifying the mitochondrial Ca2+ uniporter (MCU) and its associated proteins have opened up new windows for interrogating the molecular mechanisms of mitochondrial Ca2+ homeostasis regulation and its role in ECB coupling. Despite remarkable progress made in the past 7 years, it has been surprising, almost disappointing, that germline MCU deficiency in mice with certain genetic background yields viable pups, and knockout of the MCU in adult heart does not cause lethality. Moreover, MCU deficiency results in few adverse phenotypes, normal performance, and preserved bioenergetics in the heart at baseline. In this review, we briefly assess the existing literature on mitochondrial Ca2+ homeostasis regulation and then we consider possible explanations for why MCU-deficient mice are spared from energy crises under physiological conditions. We propose that MCU and/or mitochondrial Ca2+ may have limited ability to set ECB coupling, that other mitochondrial Ca2+ handling mechanisms may play a role, and that extra-mitochondrial Ca2+ may regulate ECB coupling. Since the heart needs to regenerate a significant amount of ATP to assure the perpetuation of heartbeats, multiple mechanisms are likely to work in concert to match energy supply with demand.
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Affiliation(s)
- Pei Wang
- Mitochondria and Metabolism Center, Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Celia Fernandez-Sanz
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Wang Wang
- Mitochondria and Metabolism Center, Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Shey-Shing Sheu
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
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44
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Nemani N, Shanmughapriya S, Madesh M. Molecular regulation of MCU: Implications in physiology and disease. Cell Calcium 2018; 74:86-93. [PMID: 29980025 PMCID: PMC6119482 DOI: 10.1016/j.ceca.2018.06.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/04/2018] [Accepted: 06/25/2018] [Indexed: 01/17/2023]
Abstract
Ca2+ flux across the inner mitochondrial membrane (IMM) regulates cellular bioenergetics, intra-cellular cytoplasmic Ca2+ signals, and various cell death pathways. Ca2+ entry into the mitochondria occurs due to the highly negative membrane potential (ΔΨm) through a selective inward rectifying MCU channel. In addition to being regulated by various mitochondrial matrix resident proteins such as MICUs, MCUb, MCUR1 and EMRE, the channel is transcriptionally regulated by upstream Ca2+ cascade, post transnational modification and by divalent cations. The mode of regulation either inhibits or enhances MCU channel activity and thus regulates mitochondrial metabolism and cell fate.
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Affiliation(s)
- Neeharika Nemani
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA
| | - Santhanam Shanmughapriya
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA
| | - Muniswamy Madesh
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA; Center for Precision Medicine, Department of Medicine, University of Texas Health San Antonio, San Antonio, Texas 78229.
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45
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Giorgi C, Marchi S, Pinton P. The machineries, regulation and cellular functions of mitochondrial calcium. Nat Rev Mol Cell Biol 2018; 19:713-730. [PMID: 30143745 DOI: 10.1038/s41580-018-0052-8] [Citation(s) in RCA: 481] [Impact Index Per Article: 80.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Calcium ions (Ca2+) are some of the most versatile signalling molecules, and they have many physiological functions, prominently including muscle contraction, neuronal excitability, cell migration and cell growth. By sequestering and releasing Ca2+, mitochondria serve as important regulators of cellular Ca2+. Mitochondrial Ca2+ also has other important functions, such as regulation of mitochondrial metabolism, ATP production and cell death. In recent years, identification of the molecular machinery regulating mitochondrial Ca2+ accumulation and efflux has expanded the number of (patho)physiological conditions that rely on mitochondrial Ca2+ homeostasis. Thus, expanding the understanding of the mechanisms of mitochondrial Ca2+ regulation and function in different cell types is an important task in biomedical research, which offers the possibility of targeting mitochondrial Ca2+ machinery for the treatment of several disorders.
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Affiliation(s)
- Carlotta Giorgi
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Saverio Marchi
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Paolo Pinton
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy. .,Maria Cecilia Hospital, GVM Care and Research, Cotignola, Ravenna, Italy.
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46
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Fan C, Fan M, Orlando BJ, Fastman NM, Zhang J, Xu Y, Chambers MG, Xu X, Perry K, Liao M, Feng L. X-ray and cryo-EM structures of the mitochondrial calcium uniporter. Nature 2018; 559:575-579. [PMID: 29995856 DOI: 10.1038/s41586-018-0330-9] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Accepted: 05/17/2018] [Indexed: 01/01/2023]
Abstract
Mitochondrial calcium uptake is critical for regulating ATP production, intracellular calcium signalling, and cell death. This uptake is mediated by a highly selective calcium channel called the mitochondrial calcium uniporter (MCU). Here, we determined the structures of the pore-forming MCU proteins from two fungi by X-ray crystallography and single-particle cryo-electron microscopy. The stoichiometry, overall architecture, and individual subunit structure differed markedly from those described in the recent nuclear magnetic resonance structure of Caenorhabditis elegans MCU. We observed a dimer-of-dimer architecture across species and chemical environments, which was corroborated by biochemical experiments. Structural analyses and functional characterization uncovered the roles of key residues in the pore. These results reveal a new ion channel architecture, provide insights into calcium coordination, selectivity and conduction, and establish a structural framework for understanding the mechanism of mitochondrial calcium uniporter function.
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Affiliation(s)
- Chao Fan
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Minrui Fan
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Nathan M Fastman
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.,Biophysics Program, Stanford University, Stanford, CA, USA
| | - Jinru Zhang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Yan Xu
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Xiaofang Xu
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.,Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Kay Perry
- NE-CAT and Dept. of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Argonne, IL, USA
| | - Maofu Liao
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
| | - Liang Feng
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA. .,Biophysics Program, Stanford University, Stanford, CA, USA.
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47
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Cryo-EM structures of fungal and metazoan mitochondrial calcium uniporters. Nature 2018; 559:580-584. [PMID: 29995857 DOI: 10.1038/s41586-018-0331-8] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 06/19/2018] [Indexed: 12/22/2022]
Abstract
The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel and a major route of calcium entry into mitochondria. How the channel catalyses ion permeation and achieves ion selectivity are not well understood, partly because MCU is thought to have a distinct architecture in comparison to other cellular channels. Here we report cryo-electron microscopy reconstructions of MCU channels from zebrafish and Cyphellophora europaea at 8.5 Å and 3.2 Å resolutions, respectively. In contrast to a previous report of pentameric stoichiometry for MCU, both channels are tetramers. The atomic model of C. europaea MCU shows that a conserved WDXXEP signature sequence forms the selectivity filter, in which calcium ions are arranged in single file. Coiled-coil legs connect the pore to N-terminal domains in the mitochondrial matrix. In C. europaea MCU, the N-terminal domains assemble as a dimer of dimers; in zebrafish MCU, they form an asymmetric crescent. The structures define principles that underlie ion permeation and calcium selectivity in this unusual channel.
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48
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Nguyen NX, Armache JP, Lee C, Yang Y, Zeng W, Mootha VK, Cheng Y, Bai XC, Jiang Y. Cryo-EM structure of a fungal mitochondrial calcium uniporter. Nature 2018; 559:570-574. [PMID: 29995855 PMCID: PMC6063787 DOI: 10.1038/s41586-018-0333-6] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 05/15/2018] [Indexed: 11/09/2022]
Abstract
The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel localized to the inner mitochondrial membrane. Here, we describe the structure of an MCU orthologue from the fungus Neosartorya fischeri (NfMCU) determined to 3.8 Å resolution by phase-plate cryo-electron microscopy. The channel is a homotetramer with two-fold symmetry in its amino-terminal domain (NTD) that adopts a similar structure to that of human MCU. The NTD assembles as a dimer of dimers to form a tetrameric ring that connects to the transmembrane domain through an elongated coiled-coil domain. The ion-conducting pore domain maintains four-fold symmetry, with the selectivity filter positioned at the start of the pore-forming TM2 helix. The aspartate and glutamate sidechains of the conserved DIME motif are oriented towards the central axis and separated by one helical turn. The structure of NfMCU offers insights into channel assembly, selective calcium permeation, and inhibitor binding.
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Affiliation(s)
- Nam X Nguyen
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jean-Paul Armache
- Howard Hughes Medical Institute and Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Changkeun Lee
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Amgen Discovery Research, Cambridge, MA, USA
| | - Yi Yang
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Weizhong Zeng
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Vamsi K Mootha
- Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Broad Institute, Cambridge, MA, USA
| | - Yifan Cheng
- Howard Hughes Medical Institute and Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Xiao-Chen Bai
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Youxing Jiang
- Howard Hughes Medical Institute and Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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49
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Yoo J, Wu M, Yin Y, Herzik MA, Lander GC, Lee SY. Cryo-EM structure of a mitochondrial calcium uniporter. Science 2018; 361:506-511. [PMID: 29954988 DOI: 10.1126/science.aar4056] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 06/20/2018] [Indexed: 11/02/2022]
Abstract
Calcium transport plays an important role in regulating mitochondrial physiology and pathophysiology. The mitochondrial calcium uniporter (MCU) is a calcium-selective ion channel that is the primary mediator for calcium uptake into the mitochondrial matrix. Here, we present the cryo-electron microscopy structure of the full-length MCU from Neurospora crassa to an overall resolution of ~3.7 angstroms. Our structure reveals a tetrameric architecture, with the soluble and transmembrane domains adopting different symmetric arrangements within the channel. The conserved W-D-Φ-Φ-E-P-V-T-Y sequence motif of MCU pore forms a selectivity filter comprising two acidic rings separated by one helical turn along the central axis of the channel pore. The structure combined with mutagenesis gives insight into the basis of calcium recognition.
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Affiliation(s)
- Jiho Yoo
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Mengyu Wu
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ying Yin
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Mark A Herzik
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Gabriel C Lander
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Seok-Yong Lee
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA.
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50
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Nguyen EK, Koval OM, Noble P, Broadhurst K, Allamargot C, Wu M, Strack S, Thiel WH, Grumbach IM. CaMKII (Ca 2+/Calmodulin-Dependent Kinase II) in Mitochondria of Smooth Muscle Cells Controls Mitochondrial Mobility, Migration, and Neointima Formation. Arterioscler Thromb Vasc Biol 2018; 38:1333-1345. [PMID: 29599132 DOI: 10.1161/atvbaha.118.310951] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/12/2018] [Indexed: 12/19/2022]
Abstract
OBJECTIVE The main objective of this study is to define the mechanisms by which mitochondria control vascular smooth muscle cell (VSMC) migration and impact neointimal hyperplasia. APPROACH AND RESULTS The multifunctional CaMKII (Ca2+/calmodulin-dependent kinase II) in the mitochondrial matrix of VSMC drove a feed-forward circuit with the mitochondrial Ca2+ uniporter (MCU) to promote matrix Ca2+ influx. MCU was necessary for the activation of mitochondrial CaMKII (mtCaMKII), whereas mtCaMKII phosphorylated MCU at the regulatory site S92 that promotes Ca2+ entry. mtCaMKII was necessary and sufficient for platelet-derived growth factor-induced mitochondrial Ca2+ uptake. This effect was dependent on MCU. mtCaMKII and MCU inhibition abrogated VSMC migration and mitochondrial translocation to the leading edge. Overexpression of wild-type MCU, but not MCU S92A, mutant in MCU-/- VSMC rescued migration and mitochondrial mobility. Inhibition of microtubule, but not of actin assembly, blocked mitochondrial mobility. The outer mitochondrial membrane GTPase Miro-1 promotes mitochondrial mobility via microtubule transport but arrests it in subcellular domains of high Ca2+ concentrations. In Miro-1-/- VSMC, mitochondrial mobility and VSMC migration were abolished, and overexpression of mtCaMKII or a CaMKII inhibitory peptide in mitochondria (mtCaMKIIN) had no effect. Consistently, inhibition of mtCaMKII increased and prolonged cytosolic Ca2+ transients. mtCaMKII inhibition diminished phosphorylation of focal adhesion kinase and myosin light chain, leading to reduced focal adhesion turnover and cytoskeletal remodeling. In a transgenic model of selective mitochondrial CaMKII inhibition in VSMC, neointimal hyperplasia was significantly reduced after vascular injury. CONCLUSIONS These findings identify mitochondrial CaMKII as a key regulator of mitochondrial Ca2+ uptake via MCU, thereby controlling mitochondrial translocation and VSMC migration after vascular injury.
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Affiliation(s)
- Emily K Nguyen
- From the Department of Internal Medicine, Carver College of Medicine (E.K.N., O.M.K., P.N., K.B., W.H.T., I.M.G.).,Interdisciplinary Program in Molecular and Cellular Biology (E.K.N.)
| | - Olha M Koval
- From the Department of Internal Medicine, Carver College of Medicine (E.K.N., O.M.K., P.N., K.B., W.H.T., I.M.G.)
| | - Paige Noble
- From the Department of Internal Medicine, Carver College of Medicine (E.K.N., O.M.K., P.N., K.B., W.H.T., I.M.G.)
| | - Kim Broadhurst
- From the Department of Internal Medicine, Carver College of Medicine (E.K.N., O.M.K., P.N., K.B., W.H.T., I.M.G.)
| | | | - Meng Wu
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy (M.W.).,High Throughput Screening Facility (M.W.).,Department of Biochemistry, Carver College of Medicine (M.W.)
| | - Stefan Strack
- Department of Pharmacology, Carver College of Medicine (S.S.)
| | - William H Thiel
- From the Department of Internal Medicine, Carver College of Medicine (E.K.N., O.M.K., P.N., K.B., W.H.T., I.M.G.).,François Abboud Cardiovascular Research Center (W.H.T., I.M.G.)
| | - Isabella M Grumbach
- From the Department of Internal Medicine, Carver College of Medicine (E.K.N., O.M.K., P.N., K.B., W.H.T., I.M.G.) .,François Abboud Cardiovascular Research Center (W.H.T., I.M.G.).,Iowa City Veterans Affairs Healthcare System (I.M.G.), University of Iowa, Iowa City
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