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Porcelli V, Barile S, Capobianco L, Barile SN, Gorgoglione R, Fiermonte G, Monti B, Lasorsa FM, Palmieri L. The mitochondrial aspartate/glutamate carrier does not transport GABA. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149487. [PMID: 38945283 DOI: 10.1016/j.bbabio.2024.149487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 06/27/2024] [Indexed: 07/02/2024]
Abstract
ɣ-aminobutyric acid (GABA) is a four‑carbon amino acid acting as the main inhibitory transmitter in the invertebrate and vertebrate nervous systems. The metabolism of GABA is well compartmentalized in the cell and the uptake of cytosolic GABA into the mitochondrial matrix is required for its degradation. A previous study carried out in the fruit fly Drosophila melanogaster indicated that the mitochondrial aspartate/glutamate carrier (AGC) is responsible for mitochondrial GABA accumulation. Here, we investigated the transport of GABA catalysed by the human and D. melanogaster AGC proteins through a well-established method for the study of the substrate specificity and the kinetic parameters of the mitochondrial carriers. In this experimental system, the D. melanogaster spliced AGC isoforms (Aralar1-PA and Aralar1-PE) and the human AGC isoforms (AGC1/aralar1 and AGC2/citrin) are unable to transport GABA both in homo- and in hetero-exchange with either glutamate or aspartate, i.e. the canonical substrates of AGC. Moreover, GABA has no inhibitory effect on the exchange activities catalysed by the investigated AGCs. Our data demonstrate that AGC does not transport GABA and the molecular identity of the GABA transporter in human and D. melanogaster mitochondria remains unknown.
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Affiliation(s)
- Vito Porcelli
- Department of Biosciences Biotechnologies and Environment, University of Bari "A. Moro", 70125, Bari, Italy
| | - Serena Barile
- Department of Biosciences Biotechnologies and Environment, University of Bari "A. Moro", 70125, Bari, Italy
| | - Loredana Capobianco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Simona Nicole Barile
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
| | - Ruggiero Gorgoglione
- Department of Biosciences Biotechnologies and Environment, University of Bari "A. Moro", 70125, Bari, Italy
| | - Giuseppe Fiermonte
- Department of Biosciences Biotechnologies and Environment, University of Bari "A. Moro", 70125, Bari, Italy
| | - Barbara Monti
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy
| | - Francesco Massimo Lasorsa
- Department of Biosciences Biotechnologies and Environment, University of Bari "A. Moro", 70125, Bari, Italy; CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy.
| | - Luigi Palmieri
- Department of Biosciences Biotechnologies and Environment, University of Bari "A. Moro", 70125, Bari, Italy; CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy.
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2
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Tavoulari S, Lacabanne D, Pereira GC, Thangaratnarajah C, King MS, He J, Chowdhury R, Tilokani L, Palmer SM, Prudent J, Walker JE, Kunji ERS. Distinct roles for the domains of the mitochondrial aspartate/glutamate carrier citrin in organellar localization and substrate transport. Mol Metab 2024:102047. [PMID: 39419476 DOI: 10.1016/j.molmet.2024.102047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 10/09/2024] [Accepted: 10/10/2024] [Indexed: 10/19/2024] Open
Abstract
OBJECTIVE Citrin, the mitochondrial aspartate/glutamate carrier isoform 2, is structurally and mechanistically the most complex SLC25 family member, because it consists of three-domains and forms a homodimer. Each protomer has an N-terminal calcium-binding domain with EF-hands, followed by a substrate-transporting carrier domain and a C-terminal domain with an amphipathic helix. The absence or dysfunction of citrin leads to citrin deficiency, a highly prevalent pan-ethnic mitochondrial disease. Here, we aim to understand the role of different citrin domains and how they contribute to pathogenic mechanisms in citrin deficiency. METHODS We have employed structural modelling and functional reconstitution of purified proteins in proteoliposomes to assess the transport activity and calcium regulation of wild-type citrin and pathogenic variants associated with citrin deficiency. We have also developed a double knock-out of citrin and aralar (AGC1), the two paralogs of the mitochondrial aspartate/glutamate carrier, in HAP1 cells to perform mitochondrial imaging and to investigate mitochondrial localisation. RESULTS Using 33 pathogenic variants of citrin we clarify determinants of sub-cellular localization and transport mechanism. We identify crucial elements of the carrier domain that are required for transport, including those involved in substrate binding, network formation and dynamics. We show that the N-terminal domain is not involved in calcium regulation of transport, as previously thought, but when mutated causes a mitochondrial import defect. CONCLUSIONS Our work introduces a new role for the N-terminal domain of citrin and demonstrates that dysfunction of the different domains contributes to distinct pathogenic mechanisms in citrin deficiency.
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Affiliation(s)
- Sotiria Tavoulari
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom.
| | - Denis Lacabanne
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Gonçalo C Pereira
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Chancievan Thangaratnarajah
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Martin S King
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Jiuya He
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Roy Chowdhury
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Lisa Tilokani
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Shane M Palmer
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - John E Walker
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom
| | - Edmund R S Kunji
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY United Kingdom.
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LaMoia TE, Hubbard BT, Guerra MT, Nasiri A, Sakuma I, Kahn M, Zhang D, Goodman RP, Nathanson MH, Sancak Y, Perelis M, Mootha VK, Shulman GI. Cytosolic calcium regulates hepatic mitochondrial oxidation, intrahepatic lipolysis, and gluconeogenesis via CAMKII activation. Cell Metab 2024; 36:2329-2340.e4. [PMID: 39153480 PMCID: PMC11446666 DOI: 10.1016/j.cmet.2024.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 05/06/2024] [Accepted: 07/19/2024] [Indexed: 08/19/2024]
Abstract
To examine the roles of mitochondrial calcium Ca2+ ([Ca2+]mt) and cytosolic Ca2+ ([Ca2+]cyt) in the regulation of hepatic mitochondrial fat oxidation, we studied a liver-specific mitochondrial calcium uniporter knockout (MCU KO) mouse model with reduced [Ca2+]mt and increased [Ca2+]cyt content. Despite decreased [Ca2+]mt, deletion of hepatic MCU increased rates of isocitrate dehydrogenase flux, α-ketoglutarate dehydrogenase flux, and succinate dehydrogenase flux in vivo. Rates of [14C16]palmitate oxidation and intrahepatic lipolysis were increased in MCU KO liver slices, which led to decreased hepatic triacylglycerol content. These effects were recapitulated with activation of CAMKII and abrogated with CAMKII knockdown, demonstrating that [Ca2+]cyt activation of CAMKII may be the primary mechanism by which MCU deletion promotes increased hepatic mitochondrial oxidation. Together, these data demonstrate that hepatic mitochondrial oxidation can be dissociated from [Ca2+]mt and reveal a key role for [Ca2+]cyt in the regulation of hepatic fat mitochondrial oxidation, intrahepatic lipolysis, gluconeogenesis, and lipid accumulation.
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Affiliation(s)
- Traci E LaMoia
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Brandon T Hubbard
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Mateus T Guerra
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Ali Nasiri
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Ikki Sakuma
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Mario Kahn
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Dongyan Zhang
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Russell P Goodman
- Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Michael H Nathanson
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yasemin Sancak
- Department of Pharmacology, University of Washington School of Medicine, Seattle, WA 98195, USA
| | | | - Vamsi K Mootha
- Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Gerald I Shulman
- Departments of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
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4
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Pannier E, Sekri A, Roux N, Vasiljevic A, El Khattabi L, Chatron N, Grotto S, Menzella D, Grangé G, Thébault F, Massardier J, Fourrage C, Lohmann L, Tsatsaris V, Putoux A, Boutaud L, Attié-Bitach T. Prenatal diagnosis of SLC25A24 Fontaine progeroid syndrome: description of the fetal phenotype, genotype and detection of parental mosaicism. Birth Defects Res 2024; 116:e2380. [PMID: 38980211 DOI: 10.1002/bdr2.2380] [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: 06/22/2023] [Revised: 05/05/2024] [Accepted: 06/23/2024] [Indexed: 07/10/2024]
Abstract
BACKGROUND Fontaine progeroid syndrome (FPS, OMIM 612289) is a recently identified genetic disorder stemming from pathogenic variants in the SLC25A24 gene, encoding a mitochondrial carrier protein. It encompasses Gorlin-Chaudry-Moss syndrome and Fontaine-Farriaux syndrome, primarily manifesting as craniosynostosis with brachycephaly, distinctive dysmorphic facial features, hypertrichosis, severe prenatal and postnatal growth restriction, limb shortening, and early aging with characteristic skin changes, phalangeal anomalies, and genital malformations. CASES All known occurrences of FPS have been postnatally observed until now. Here, we present the first two prenatal cases identified during the second trimester of pregnancy. While affirming the presence of most postnatal abnormalities in prenatal cases, we note the absence of a progeroid appearance in young fetuses. Notably, our reports introduce new phenotypic features like encephalocele and nephromegaly, which were previously unseen postnatally. Moreover, paternal SLC25A24 mosaicism was detected in one case. CONCLUSIONS We present the initial two fetal instances of FPS, complemented by thorough phenotypic and genetic assessments. Our findings expand the phenotypical spectrum of FPS, unveiling new fetal phenotypic characteristics. Furthermore, one case underscores a potential novel inheritance pattern in this disorder. Lastly, our observations emphasize the efficacy of exome/genome sequencing in both prenatal and postmortem diagnosis of rare polymalformative syndromes with a normal karyotype and array-based comparative genomic hybridization (CGH).
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Affiliation(s)
- Emmanuelle Pannier
- Département d'Obstétrique et Médecine Fœtale, Maternité Port-Royal, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, FHU PREMA, Paris, France
| | - Abel Sekri
- Centre de Pathologie et Neuropathologie Est, Groupement Hospitalier Est, Bron, France
| | - Nathalie Roux
- Département de Médecine Génomique Des Maladies Rares, Hôpital Necker, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Alexandre Vasiljevic
- Centre de Pathologie et Neuropathologie Est, Groupement Hospitalier Est, Bron, France
| | - Laïla El Khattabi
- Médecine Génomique, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, Université Paris Cité, Paris, France
| | - Nicolas Chatron
- Service de Génétique, Hospices Civils de Lyon, Groupement Hospitalier Est, Bron, France
- Laboratoire Physiopathologie et Génétique du Neurone et du Muscle, U1315 UMR5261, Université Claude Bernard Lyon1, INSERM, CNRS, Institute NeuroMyoGène, Bron, France
| | - Sarah Grotto
- Génétique Clinique, Maternité Port-Royal, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Delphine Menzella
- Département d'Obstétrique, Institut Mutualiste Montsouris, Paris, France
| | - Gilles Grangé
- Département d'Obstétrique et Médecine Fœtale, Maternité Port-Royal, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, FHU PREMA, Paris, France
| | - Florent Thébault
- Département d'Obstétrique et Médecine Fœtale, Maternité Port-Royal, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, FHU PREMA, Paris, France
| | - Jérôme Massardier
- Hôpital Femme Mère Enfant, Service de Gynécologie Obstétrique et Médecine Fœtale, Bron, France
| | - Cécile Fourrage
- Plateforme Bioinformatique Imagine, Hôpital Necker, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Laurence Lohmann
- Département de Cytogénétique, Laboratoire CERBA, Saint-Ouen-l'Aumône, France
| | - Vassilis Tsatsaris
- Département d'Obstétrique et Médecine Fœtale, Maternité Port-Royal, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, FHU PREMA, Paris, France
| | - Audrey Putoux
- Service de Génétique, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Hospices Civils de Lyon, Groupement Hospitalier Est, Bron, France
- Université Claude Bernard Lyon1, INSERM, CNRS, Centre de Recherche en Neurosciences de Lyon U1028 UMR592, GENDEV, Bron, France
| | - Lucile Boutaud
- Département de Médecine Génomique Des Maladies Rares, Hôpital Necker, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Tania Attié-Bitach
- Département de Médecine Génomique Des Maladies Rares, Hôpital Necker, Assistance Publique-Hôpitaux de Paris, Paris, France
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Hansen FM, Kremer LS, Karayel O, Bludau I, Larsson NG, Kühl I, Mann M. Mitochondrial phosphoproteomes are functionally specialized across tissues. Life Sci Alliance 2024; 7:e202302147. [PMID: 37984987 PMCID: PMC10662294 DOI: 10.26508/lsa.202302147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 11/03/2023] [Accepted: 11/07/2023] [Indexed: 11/22/2023] Open
Abstract
Mitochondria are essential organelles whose dysfunction causes human pathologies that often manifest in a tissue-specific manner. Accordingly, mitochondrial fitness depends on versatile proteomes specialized to meet diverse tissue-specific requirements. Increasing evidence suggests that phosphorylation may play an important role in regulating tissue-specific mitochondrial functions and pathophysiology. Building on recent advances in mass spectrometry (MS)-based proteomics, we here quantitatively profile mitochondrial tissue proteomes along with their matching phosphoproteomes. We isolated mitochondria from mouse heart, skeletal muscle, brown adipose tissue, kidney, liver, brain, and spleen by differential centrifugation followed by separation on Percoll gradients and performed high-resolution MS analysis of the proteomes and phosphoproteomes. This in-depth map substantially quantifies known and predicted mitochondrial proteins and provides a resource of core and tissue-specific mitochondrial proteins (mitophos.de). Predicting kinase substrate associations for different mitochondrial compartments indicates tissue-specific regulation at the phosphoproteome level. Illustrating the functional value of our resource, we reproduce mitochondrial phosphorylation events on dynamin-related protein 1 responsible for its mitochondrial recruitment and fission initiation and describe phosphorylation clusters on MIGA2 linked to mitochondrial fusion.
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Affiliation(s)
- Fynn M Hansen
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Laura S Kremer
- https://ror.org/056d84691 Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Ozge Karayel
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Isabell Bludau
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Nils-Göran Larsson
- https://ror.org/056d84691 Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Inge Kühl
- Department of Cell Biology, Institute of Integrative Biology of the Cell, UMR9198, CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Matthias Mann
- https://ror.org/04py35477 Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
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6
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Mishra G, Coyne LP, Chen XJ. Adenine nucleotide carrier protein dysfunction in human disease. IUBMB Life 2023; 75:911-925. [PMID: 37449547 PMCID: PMC10592433 DOI: 10.1002/iub.2767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/23/2023] [Indexed: 07/18/2023]
Abstract
Adenine nucleotide translocase (ANT) is the prototypical member of the mitochondrial carrier protein family, primarily involved in ADP/ATP exchange across the inner mitochondrial membrane. Several carrier proteins evolutionarily related to ANT, including SLC25A24 and SLC25A25, are believed to promote the exchange of cytosolic ATP-Mg2+ with phosphate in the mitochondrial matrix. They allow a net accumulation of adenine nucleotides inside mitochondria, which is essential for mitochondrial biogenesis and cell growth. In the last two decades, mutations in the heart/muscle isoform 1 of ANT (ANT1) and the ATP-Mg2+ transporters have been found to cause a wide spectrum of human diseases by a recessive or dominant mechanism. Although loss-of-function recessive mutations cause a defect in oxidative phosphorylation and an increase in oxidative stress which drives the pathology, it is unclear how the dominant missense mutations in these proteins cause human diseases. In this review, we focus on how yeast was productively used as a model system for the understanding of these dominant diseases. We also describe the relationship between the structure and function of ANT and how this may relate to various pathologies. Particularly, mutations in Aac2, the yeast homolog of ANT, were recently found to clog the mitochondrial protein import pathway. This leads to mitochondrial precursor overaccumulation stress (mPOS), characterized by the toxic accumulation of unimported mitochondrial proteins in the cytosol. We anticipate that in coming years, yeast will continue to serve as a useful model system for the mechanistic understanding of mitochondrial protein import clogging and related pathologies in humans.
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Affiliation(s)
- Gargi Mishra
- Department of Biochemistry and Molecular Biology, Norton College of Medicine, State University of New York Upstate Medical University, Syracuse, New York, USA
| | - Liam P Coyne
- Department of Biochemistry and Molecular Biology, Norton College of Medicine, State University of New York Upstate Medical University, Syracuse, New York, USA
| | - Xin Jie Chen
- Department of Biochemistry and Molecular Biology, Norton College of Medicine, State University of New York Upstate Medical University, Syracuse, New York, USA
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7
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de Ridder I, Kerkhofs M, Lemos FO, Loncke J, Bultynck G, Parys JB. The ER-mitochondria interface, where Ca 2+ and cell death meet. Cell Calcium 2023; 112:102743. [PMID: 37126911 DOI: 10.1016/j.ceca.2023.102743] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 05/03/2023]
Abstract
Endoplasmic reticulum (ER)-mitochondria contact sites are crucial to allow Ca2+ flux between them and a plethora of proteins participate in tethering both organelles together. Inositol 1,4,5-trisphosphate receptors (IP3Rs) play a pivotal role at such contact sites, participating in both ER-mitochondria tethering and as Ca2+-transport system that delivers Ca2+ from the ER towards mitochondria. At the ER-mitochondria contact sites, the IP3Rs function as a multi-protein complex linked to the voltage-dependent anion channel 1 (VDAC1) in the outer mitochondrial membrane, via the chaperone glucose-regulated protein 75 (GRP75). This IP3R-GRP75-VDAC1 complex supports the efficient transfer of Ca2+ from the ER into the mitochondrial intermembrane space, from which the Ca2+ ions can reach the mitochondrial matrix through the mitochondrial calcium uniporter. Under physiological conditions, basal Ca2+ oscillations deliver Ca2+ to the mitochondrial matrix, thereby stimulating mitochondrial oxidative metabolism. However, when mitochondrial Ca2+ overload occurs, the increase in [Ca2+] will induce the opening of the mitochondrial permeability transition pore, thereby provoking cell death. The IP3R-GRP75-VDAC1 complex forms a hub for several other proteins that stabilize the complex and/or regulate the complex's ability to channel Ca2+ into the mitochondria. These proteins and their mechanisms of action are discussed in the present review with special attention for their role in pathological conditions and potential implication for therapeutic strategies.
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Affiliation(s)
- Ian de Ridder
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Martijn Kerkhofs
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Fernanda O Lemos
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Jens Loncke
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Geert Bultynck
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
| | - Jan B Parys
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
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8
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del Arco A, González-Moreno L, Pérez-Liébana I, Juaristi I, González-Sánchez P, Contreras L, Pardo B, Satrústegui J. Regulation of neuronal energy metabolism by calcium: Role of MCU and Aralar/malate-aspartate shuttle. BIOCHIMICA ET BIOPHYSICA ACTA (BBA) - MOLECULAR CELL RESEARCH 2023; 1870:119468. [PMID: 36997074 DOI: 10.1016/j.bbamcr.2023.119468] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/17/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023]
Abstract
Calcium is a major regulator of cellular metabolism. Calcium controls mitochondrial respiration, and calcium signaling is used to meet cellular energetic demands through energy production in the organelle. Although it has been widely assumed that Ca2+-actions require its uptake by mitochondrial calcium uniporter (MCU), alternative pathways modulated by cytosolic Ca2+ have been recently proposed. Recent findings have indicated a role for cytosolic Ca2+ signals acting on mitochondrial NADH shuttles in the control of cellular metabolism in neurons using glucose as fuel. It has been demonstrated that AGC1/Aralar, the component of the malate/aspartate shuttle (MAS) regulated by cytosolic Ca2+, participates in the maintenance of basal respiration exerted through Ca2+-fluxes between ER and mitochondria, whereas mitochondrial Ca2+-uptake by MCU does not contribute. Aralar/MAS pathway, activated by small cytosolic Ca2+ signals, provides in fact substrates, redox equivalents and pyruvate, fueling respiration. Upon activation and increases in workload, neurons upregulate OxPhos, cytosolic pyruvate production and glycolysis, together with glucose uptake, in a Ca2+-dependent way, and part of this upregulation is via Ca2+ signaling. Both MCU and Aralar/MAS contribute to OxPhos upregulation, Aralar/MAS playing a major role, especially at small and submaximal workloads. Ca2+ activation of Aralar/MAS, by increasing cytosolic NAD+/NADH provides Ca2+-dependent increases in glycolysis and cytosolic pyruvate production priming respiration as a feed-forward mechanism in response to workload. Thus, except for glucose uptake, these processes are dependent on Aralar/MAS, whereas MCU is the relevant target for Ca2+ signaling when MAS is bypassed, by using pyruvate or β-hydroxybutyrate as substrates.
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9
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Lally S, Walsh N, Kenny J, Franklin O, Cotter M, Richardson S, McEligott F, Finan A. Fontaine progeroid syndrome-A case report. Clin Case Rep 2022; 10:e6291. [PMID: 36093452 PMCID: PMC9448962 DOI: 10.1002/ccr3.6291] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 06/10/2022] [Accepted: 07/16/2022] [Indexed: 11/11/2022] Open
Abstract
Fontaine progeroid syndrome (FPS) is an autosomal dominant condition caused by pathogenic variants in the SLC25A24 gene. Eleven cases have been described in the literature, with early lethality in some. We discuss the clinical course of a patient from birth until his death at 7 months.
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Affiliation(s)
- Sinéad Lally
- Department of Paediatrics Cavan Monaghan Hospital, RCSI Hospital Group Cavan Ireland
| | - Nicola Walsh
- Department of Clinical Genetics Children's Health Ireland at Crumlin Dublin 12 Ireland
| | - Janna Kenny
- Department of Clinical Genetics Children's Health Ireland at Crumlin Dublin 12 Ireland
| | - Orla Franklin
- Department of Paediatric Cardiology, Children's Health Ireland at Crumlin Dublin 12 Ireland
- Department of Paediatric Cardiology Children's Health Ireland at Temple Street Dublin 1 Ireland
| | - Melanie Cotter
- Department of Haematology Children's Health Ireland at Crumlin Dublin 12 Ireland
- Department of Haematology Children's Health Ireland at Temple Street Dublin 1 Ireland
| | - Sarah Richardson
- Department of Paediatrics Children's Health Ireland at Temple Street Dublin 1 Ireland
| | - Fiona McEligott
- Department of Palliative Medicine Children's Health Ireland at Temple Street Dublin 1 Ireland
| | - Alan Finan
- Department of Paediatrics Cavan Monaghan Hospital, RCSI Hospital Group Cavan Ireland
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10
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Sargsyan Y, Kalinowski J, Thoms S. Calcium in peroxisomes: An essential messenger in an essential cell organelle. Front Cell Dev Biol 2022; 10:992235. [PMID: 36111338 PMCID: PMC9468670 DOI: 10.3389/fcell.2022.992235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022] Open
Abstract
Calcium is a central signal transduction element in biology. Peroxisomes are essential cellular organelles, yet calcium handling in peroxisomes has been contentious. Recent advances show that peroxisomes are part of calcium homeostasis in cardiac myocytes and therefore may contribute to or even shape their calcium-dependent functionality. However, the mechanisms of calcium movement between peroxisomes and other cellular sites and their mediators remain elusive. Here, we review calcium handling in peroxisomes in concert with other organelles and summarize the most recent knowledge on peroxisomal involvement in calcium dynamics with a focus on mammalian cells.
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Affiliation(s)
- Yelena Sargsyan
- Department for Biochemistry and Molecular Medicine, Medical School EWL, Bielefeld University, Bielefeld, Germany
- Department of Child and Adolescent Health, University Medical Center, Göttingen, Germany
| | - Julia Kalinowski
- Department for Biochemistry and Molecular Medicine, Medical School EWL, Bielefeld University, Bielefeld, Germany
| | - Sven Thoms
- Department for Biochemistry and Molecular Medicine, Medical School EWL, Bielefeld University, Bielefeld, Germany
- Department of Child and Adolescent Health, University Medical Center, Göttingen, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen, Germany
- *Correspondence: Sven Thoms,
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11
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Characterization of methylation patterns associated with lifestyle factors and vitamin D supplementation in a healthy elderly cohort from Southwest Sweden. Sci Rep 2022; 12:12670. [PMID: 35879377 PMCID: PMC9310683 DOI: 10.1038/s41598-022-15924-x] [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: 03/03/2022] [Accepted: 07/01/2022] [Indexed: 11/08/2022] Open
Abstract
Numerous studies have shown that lifestyle factors, such as regular physical activity and vitamin D intake, may remarkably improve overall health and mental wellbeing. This is especially important in older adults whose vitamin D deficiency occurs with a high prevalence. This study aimed to examine the influence of lifestyle and vitamin D on global DNA methylation patterns in an elderly cohort in Southwest of Sweden. We also sought to examine the methylation levels of specific genes involved in vitamin D's molecular and metabolic activated pathways. We performed a genome wide methylation analysis, using Illumina Infinium DNA Methylation EPIC 850kBeadChip array, on 277 healthy individuals from Southwest Sweden at the age of 70–95. The study participants also answered queries on lifestyle, vitamin intake, heart medication, and estimated health. Vitamin D intake did not in general affect methylation patterns, which is in concert with other studies. However, when comparing the group of individuals taking vitamin supplements, including vitamin D, with those not taking supplements, a difference in methylation in the solute carrier family 25 (SCL25A24) gene was found. This confirms a previous finding, where changes in expression of SLC25A24 were associated with vitamin D treatment in human monocytes. The combination of vitamin D intake and high physical activity increased methylation of genes linked to regulation of vitamin D receptor pathway, the Wnt pathway and general cancer processes. To our knowledge, this is the first study detecting epigenetic markers associated with the combined effects of vitamin D supplementation and high physical activity. These results deserve to be further investigated in an extended, interventional study cohort, where also the levels of 25(OH)D3 can be monitored.
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12
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Pengelly RJ, Bakhtiar D, Borovská I, Královičová J, Vořechovský I. Exonic splicing code and protein binding sites for calcium. Nucleic Acids Res 2022; 50:5493-5512. [PMID: 35474482 PMCID: PMC9177970 DOI: 10.1093/nar/gkac270] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/01/2022] [Accepted: 04/05/2022] [Indexed: 11/12/2022] Open
Abstract
Auxilliary splicing sequences in exons, known as enhancers (ESEs) and silencers (ESSs), have been subject to strong selection pressures at the RNA and protein level. The protein component of this splicing code is substantial, recently estimated at ∼50% of the total information within ESEs, but remains poorly understood. The ESE/ESS profiles were previously associated with the Irving-Williams (I-W) stability series for divalent metals, suggesting that the ESE/ESS evolution was shaped by metal binding sites. Here, we have examined splicing activities of exonic sequences that encode protein binding sites for Ca2+, a weak binder in the I-W affinity order. We found that predicted exon inclusion levels for the EF-hand motifs and for Ca2+-binding residues in nonEF-hand proteins were higher than for average exons. For canonical EF-hands, the increase was centred on the EF-hand chelation loop and, in particular, on Ca2+-coordinating residues, with a 1>12>3∼5>9 hierarchy in the 12-codon loop consensus and usage bias at codons 1 and 12. The same hierarchy but a lower increase was observed for noncanonical EF-hands, except for S100 proteins. EF-hand loops preferentially accumulated exon splits in two clusters, one located in their N-terminal halves and the other around codon 12. Using splicing assays and published crosslinking and immunoprecipitation data, we identify candidate trans-acting factors that preferentially bind conserved GA-rich motifs encoding negatively charged amino acids in the loops. Together, these data provide evidence for the high capacity of codons for Ca2+-coordinating residues to be retained in mature transcripts, facilitating their exon-level expansion during eukaryotic evolution.
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Affiliation(s)
- Reuben J Pengelly
- University of Southampton, Faculty of Medicine, Southampton SO16 6YD, UK
| | - Dara Bakhtiar
- University of Southampton, Faculty of Medicine, Southampton SO16 6YD, UK
| | - Ivana Borovská
- Slovak Academy of Sciences, Centre of Biosciences, 840 05 Bratislava, Slovak Republic
| | - Jana Královičová
- University of Southampton, Faculty of Medicine, Southampton SO16 6YD, UK
- Slovak Academy of Sciences, Centre of Biosciences, 840 05 Bratislava, Slovak Republic
- Slovak Academy of Sciences, Institute of Zoology, 845 06 Bratislava, Slovak Republic
| | - Igor Vořechovský
- University of Southampton, Faculty of Medicine, Southampton SO16 6YD, UK
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13
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Gao LF, Zhong Y, Long T, Wang X, Zhu JX, Wang XY, Hu ZY, Li ZG. Tumor bud-derived CCL5 recruits fibroblasts and promotes colorectal cancer progression via CCR5-SLC25A24 signaling. J Exp Clin Cancer Res 2022; 41:81. [PMID: 35241150 PMCID: PMC8892738 DOI: 10.1186/s13046-022-02300-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 02/25/2022] [Indexed: 12/17/2022] Open
Abstract
Background Tumor budding is included in the routine diagnosis of colorectal cancer (CRC) and is considered a tumor prognostic factor independent of TNM staging. This study aimed to identify the fibroblast-mediated effect of tumor bud-derived C–C chemokine ligand 5 (CCL5) on the tumor microenvironment (TME). Methods Recruitment assays and a human cytokine array were used to detect the main cytokines that CRC tumor buds secrete to recruit fibroblasts. siRNA transfection and inhibitor treatment were used to investigate the role of fibroblast CCL5 receptors in fibroblast recruitment. Subsequently, transcriptome sequencing was performed to explore the molecular changes occurring in fibroblasts upon stimulation with CCL5. Finally, clinical specimens and orthotopic xenograft mouse models were studied to explore the contribution of CCL5 to angiogenesis and collagen synthesis. Results Hematoxylin–eosin staining and immunochemistry revealed a higher number of fibroblasts at the invasive front of CRC tissue showing tumor budding than at sites without tumor budding. In vitro experiments demonstrated that CCL5 derived from tumor buds could recruit fibroblasts by acting on the CCR5 receptors on fibroblasts. Tumor bud-derived CCL5 could also positively regulate solute carrier family 25 member 24 (SLC25A24) expression in fibroblasts, potentially activating pAkt-pmTOR signaling. Moreover, CCL5 could increase the number of α-SMAhigh CD90high FAPlow fibroblasts and thus promote tumor angiogenesis by enhancing VEGFA expression and making fibroblasts transdifferentiate into vascular endothelial cells. Finally, the results also showed that CCL5 could promote collagen synthesis through fibroblasts, thus contributing to tumor progression. Conclusions At the invasive front of CRC, tumor bud-derived CCL5 can recruit fibroblasts via CCR5-SLC25A24 signaling, further promoting angiogenesis and collagen synthesis via recruited fibroblasts, and eventually create a tumor-promoting microenvironment. Therefore, CCL5 may serve as a potential diagnostic marker and therapeutic target for tumor budding in CRC. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-022-02300-w.
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Affiliation(s)
- Ling-Fang Gao
- Department of Pathology, Shenzhen Hospital, Southern Medical University, Shenzhen, 518101, Guangdong, China.,Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Yan Zhong
- Department of Pathology, Shenzhen Hospital, Southern Medical University, Shenzhen, 518101, Guangdong, China
| | - Ting Long
- Department of Pathology, Shenzhen Hospital, Southern Medical University, Shenzhen, 518101, Guangdong, China
| | - Xia Wang
- Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Jia-Xian Zhu
- Department of Pathology, Shenzhen Hospital, Southern Medical University, Shenzhen, 518101, Guangdong, China
| | - Xiao-Yan Wang
- Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China.,Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Zhi-Yan Hu
- Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China.,Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Zu-Guo Li
- Department of Pathology, Shenzhen Hospital, Southern Medical University, Shenzhen, 518101, Guangdong, China. .,Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China.
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14
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Nguyen NT, Nguyen TT, Park KS. Oxidative Stress Related to Plasmalemmal and Mitochondrial Phosphate Transporters in Vascular Calcification. Antioxidants (Basel) 2022; 11:antiox11030494. [PMID: 35326144 PMCID: PMC8944874 DOI: 10.3390/antiox11030494] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 02/26/2022] [Accepted: 02/28/2022] [Indexed: 12/04/2022] Open
Abstract
Inorganic phosphate (Pi) is essential for maintaining cellular function but excess of Pi leads to serious complications, including vascular calcification. Accumulating evidence suggests that oxidative stress contributes to the pathogenic progression of calcific changes. However, the molecular mechanism underlying Pi-induced reactive oxygen species (ROS) generation and its detrimental consequences remain unclear. Type III Na+-dependent Pi cotransporter, PiT-1/-2, play a significant role in Pi uptake of vascular smooth muscle cells. Pi influx via PiT-1/-2 increases the abundance of PiT-1/-2 and depolarization-activated Ca2+ entry due to its electrogenic properties, which may lead to Ca2+ and Pi overload and oxidative stress. At least four mitochondrial Pi transporters are suggested, among which the phosphate carrier (PiC) is known to be mainly involved in mitochondrial Pi uptake. Pi transport via PiC may induce hyperpolarization and superoxide generation, which may lead to mitochondrial dysfunction and endoplasmic reticulum stress, together with generation of cytosolic ROS. Increase in net influx of Ca2+ and Pi and their accumulation in the cytosol and mitochondrial matrix synergistically increases oxidative stress and osteogenic differentiation, which could be prevented by suppressing either Ca2+ or Pi overload. Therapeutic strategies targeting plasmalemmal and mitochondrial Pi transports can protect against Pi-induced oxidative stress and vascular calcification.
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Affiliation(s)
- Nhung Thi Nguyen
- Department of Physiology, Wonju College of Medicine, Yonsei University, Wonju 26426, Korea;
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju 26426, Korea
- Medical Doctor Program, College of Health Sciences, VinUniversity, Hanoi 12406, Vietnam
| | - Tuyet Thi Nguyen
- Department of Physiology, Wonju College of Medicine, Yonsei University, Wonju 26426, Korea;
- Internal Medicine Residency Program, College of Health Sciences, VinUniversity, Hanoi 12406, Vietnam
- Correspondence: (T.T.N.); (K.-S.P.); Tel.: +84-247-108-9779 (T.T.N.); +82-33-741-0294 (K.-S.P.)
| | - Kyu-Sang Park
- Department of Physiology, Wonju College of Medicine, Yonsei University, Wonju 26426, Korea;
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju 26426, Korea
- Correspondence: (T.T.N.); (K.-S.P.); Tel.: +84-247-108-9779 (T.T.N.); +82-33-741-0294 (K.-S.P.)
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15
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Pardo B, Herrada-Soler E, Satrústegui J, Contreras L, del Arco A. AGC1 Deficiency: Pathology and Molecular and Cellular Mechanisms of the Disease. Int J Mol Sci 2022; 23:528. [PMID: 35008954 PMCID: PMC8745132 DOI: 10.3390/ijms23010528] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/23/2021] [Accepted: 12/24/2021] [Indexed: 02/01/2023] Open
Abstract
AGC1/Aralar/Slc25a12 is the mitochondrial carrier of aspartate-glutamate, the regulatory component of the NADH malate-aspartate shuttle (MAS) that transfers cytosolic redox power to neuronal mitochondria. The deficiency in AGC1/Aralar leads to the human rare disease named "early infantile epileptic encephalopathy 39" (EIEE 39, OMIM # 612949) characterized by epilepsy, hypotonia, arrested psychomotor neurodevelopment, hypo myelination and a drastic drop in brain aspartate (Asp) and N-acetylaspartate (NAA). Current evidence suggest that neurons are the main brain cell type expressing Aralar. However, paradoxically, glial functions such as myelin and Glutamine (Gln) synthesis are markedly impaired in AGC1 deficiency. Herein, we discuss the role of the AGC1/Aralar-MAS pathway in neuronal functions such as Asp and NAA synthesis, lactate use, respiration on glucose, glutamate (Glu) oxidation and other neurometabolic aspects. The possible mechanism triggering the pathophysiological findings in AGC1 deficiency, such as epilepsy and postnatal hypomyelination observed in humans and mice, are also included. Many of these mechanisms arise from findings in the aralar-KO mice model that extensively recapitulate the human disease including the astroglial failure to synthesize Gln and the dopamine (DA) mishandling in the nigrostriatal system. Epilepsy and DA mishandling are a direct consequence of the metabolic defect in neurons due to AGC1/Aralar deficiency. However, the deficits in myelin and Gln synthesis may be a consequence of neuronal affectation or a direct effect of AGC1/Aralar deficiency in glial cells. Further research is needed to clarify this question and delineate the transcellular metabolic fluxes that control brain functions. Finally, we discuss therapeutic approaches successfully used in AGC1-deficient patients and mice.
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Affiliation(s)
- Beatriz Pardo
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Eduardo Herrada-Soler
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Laura Contreras
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Araceli del Arco
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro Regional de Investigaciones Biomédicas, Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla La Mancha, 45071 Toledo, Spain
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16
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A pair of transporters controls mitochondrial Zn 2+ levels to maintain mitochondrial homeostasis. Protein Cell 2021; 13:180-202. [PMID: 34687432 PMCID: PMC8901913 DOI: 10.1007/s13238-021-00881-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/02/2021] [Indexed: 12/15/2022] Open
Abstract
Zn2+ is required for the activity of many mitochondrial proteins, which regulate mitochondrial dynamics, apoptosis and mitophagy. However, it is not understood how the proper mitochondrial Zn2+ level is achieved to maintain mitochondrial homeostasis. Using Caenorhabditis elegans, we reveal here that a pair of mitochondrion-localized transporters controls the mitochondrial level of Zn2+. We demonstrate that SLC-30A9/ZnT9 is a mitochondrial Zn2+ exporter. Loss of SLC-30A9 leads to mitochondrial Zn2+ accumulation, which damages mitochondria, impairs animal development and shortens the life span. We further identify SLC-25A25/SCaMC-2 as an important regulator of mitochondrial Zn2+ import. Loss of SLC-25A25 suppresses the abnormal mitochondrial Zn2+ accumulation and defective mitochondrial structure and functions caused by loss of SLC-30A9. Moreover, we reveal that the endoplasmic reticulum contains the Zn2+ pool from which mitochondrial Zn2+ is imported. These findings establish the molecular basis for controlling the correct mitochondrial Zn2+ levels for normal mitochondrial structure and functions.
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17
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Jabalameli MR, Fitzpatrick FM, Colombo R, Howles SA, Leggatt G, Walker V, Wiberg A, Kunji ERS, Ennis S. Exome sequencing identifies a disease variant of the mitochondrial ATP-Mg/Pi carrier SLC25A25 in two families with kidney stones. Mol Genet Genomic Med 2021; 9:e1749. [PMID: 34346195 PMCID: PMC8683635 DOI: 10.1002/mgg3.1749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 05/13/2021] [Accepted: 07/01/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Calcium kidney stones are common and recurrences are often not preventable by available empiric remedies. Their etiology is multifactorial and polygenic, and an increasing number of genes are implicated. Their identification will enable improved management. METHODS DNA from three stone-formers in a Southampton family (UK) and two from an Italian family were analyzed independently by whole exome sequencing and selected variants were genotyped across all available members of both pedigrees. A disease variant of SLC25A25 (OMIM 608745), encoding the mitochondrial ATP-Mg/Pi carrier 3 (APC3) was identified, and analyzed structurally and functionally with respect to its calcium-regulated transport activity. RESULTS All five patients had a heterozygous dominant SLC25A25 variant (rs140777921; GRCh37.p13: chr 9 130868670 G>C; p.Gln349His; Reference Sequence NM_001006641.3). Non-stone formers also carried the variant indicating incomplete penetrance. Modeling suggests that the variant lacks a conserved polar interaction, which may cause structural instability. Calcium-regulated ATP transport was reduced to ~20% of the wild type, showing a large reduction in function. CONCLUSION The transporter is important in regulating mitochondrial ATP production. This rare variant may increase urine lithogenicity through impaired provision of ATP for solute transport processes in the kidney, and/or for purinergic signaling. Variants found in other genes may compound this abnormality.
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Affiliation(s)
- M Reza Jabalameli
- Department of Human Genetics and Genomic Medicine, University of Southampton, Southampton, UK
| | - Fiona M Fitzpatrick
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Roberto Colombo
- Faculty of Medicine 'Agostino Gemelli', Catholic University of the Sacred Heart, Rome, Italy.,Center for the Study of Rare Inherited Diseases, Niguarda Ca´Granda Metropolitan Hospital, Milan, Italy
| | - Sarah A Howles
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK.,Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Gary Leggatt
- Department of Human Genetics and Genomic Medicine, University of Southampton, Southampton, UK.,Wessex Kidney Centre, Queen Alexandra Hospital, Portsmouth, UK
| | - Valerie Walker
- Department of Clinical Biochemistry, University Hospital Southampton, Southampton, UK
| | - Akira Wiberg
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Edmund R S Kunji
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Sarah Ennis
- Department of Human Genetics and Genomic Medicine, University of Southampton, Southampton, UK
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18
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Kunji ERS, King MS, Ruprecht JJ, Thangaratnarajah C. The SLC25 Carrier Family: Important Transport Proteins in Mitochondrial Physiology and Pathology. Physiology (Bethesda) 2021; 35:302-327. [PMID: 32783608 PMCID: PMC7611780 DOI: 10.1152/physiol.00009.2020] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Members of the mitochondrial carrier family (SLC25) transport a variety of compounds across the inner membrane of mitochondria. These transport steps provide building blocks for the cell and link the pathways of the mitochondrial matrix and cytosol. An increasing number of diseases and pathologies has been associated with their dysfunction. In this review, the molecular basis of these diseases is explained based on our current understanding of their transport mechanism.
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Affiliation(s)
- Edmund R S Kunji
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Martin S King
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Jonathan J Ruprecht
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Chancievan Thangaratnarajah
- Groningen Biomolecular Sciences and Biotechnology Institute, Membrane Enzymology, University of Groningen, Groningen, The Netherlands
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19
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Ca 2+-regulated mitochondrial carriers of ATP-Mg 2+/Pi: Evolutionary insights in protozoans. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119038. [PMID: 33839167 DOI: 10.1016/j.bbamcr.2021.119038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 11/23/2022]
Abstract
In addition to its uptake across the Ca2+ uniporter, intracellular calcium signals can stimulate mitochondrial metabolism activating metabolite exchangers of the inner mitochondrial membrane belonging to the mitochondrial carrier family (SLC25). One of these Ca2+-regulated mitochondrial carriers (CaMCs) are the reversible ATP-Mg2+/Pi transporters, or SCaMCs, required for maintaining optimal adenine nucleotide (AdN) levels in the mitochondrial matrix representing an alternative transporter to the ADP/ATP translocases (AAC). This CaMC has a distinctive Calmodulin-like (CaM-like) domain fused to the carrier domain that makes its transport activity strictly dependent on cytosolic Ca2+ signals. Here we investigate about its origin analysing its distribution and features in unicellular eukaryotes. Unexpectedly, we find two types of ATP-Mg2+/Pi carriers, the canonical ones and shortened variants lacking the CaM-like domain. Phylogenetic analysis shows that both SCaMC variants have a common origin, unrelated to AACs, suggesting in turn that recurrent losses of the regulatory module have occurred in the different phyla. They are excluding variants that show a more limited distribution and less conservation than AACs. Interestingly, these truncated variants of SCaMC are found almost exclusively in parasitic protists, such as apicomplexans, kinetoplastides or animal-patogenic oomycetes, and in green algae, suggesting that its lost could be related to certain life-styles. In addition, we find an intricate structural diversity in these variants that may be associated with their pathogenicity. The consequences on SCaMC functions of these new SCaMC-b variants are discussed.
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20
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Sagar S, Kapoor H, Chaudhary N, Roy SS. Cellular and mitochondrial calcium communication in obstructive lung disorders. Mitochondrion 2021; 58:184-199. [PMID: 33766748 DOI: 10.1016/j.mito.2021.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 03/03/2021] [Accepted: 03/15/2021] [Indexed: 12/14/2022]
Abstract
Calcium (Ca2+) signalling is well known to dictate cellular functioning and fate. In recent years, the accumulation of Ca2+ in the mitochondria has emerged as an important factor in Chronic Respiratory Diseases (CRD) such as Asthma and Chronic Obstructive Pulmonary Disease (COPD). Various reports underline an aberrant increase in the intracellular Ca2+, leading to mitochondrial ROS generation, and further activation of the apoptotic pathway in these diseases. Mitochondria contribute to Ca2+ buffering which in turn regulates mitochondrial metabolism and ATP production. Disruption of this Ca2+ balance leads to impaired cellular processes like apoptosis or necrosis and thus contributes to the pathophysiology of airway diseases. This review highlights the key role of cytoplasmic and mitochondrial Ca2+ signalling in regulating CRD, such as asthma and COPD. A better understanding of the dysregulation of mitochondrial Ca2+ homeostasis in these diseases could provide cues for the development of advanced therapeutic interventions in these diseases.
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Affiliation(s)
- Shakti Sagar
- CSIR-Institute of Genomics & Integrative Biology, New Delhi, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Himanshi Kapoor
- CSIR-Institute of Genomics & Integrative Biology, New Delhi, India
| | - Nisha Chaudhary
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, New Delhi, India
| | - Soumya Sinha Roy
- CSIR-Institute of Genomics & Integrative Biology, New Delhi, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India.
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21
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Palmieri F, Scarcia P, Monné M. Diseases Caused by Mutations in Mitochondrial Carrier Genes SLC25: A Review. Biomolecules 2020; 10:biom10040655. [PMID: 32340404 PMCID: PMC7226361 DOI: 10.3390/biom10040655] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 12/13/2022] Open
Abstract
In the 1980s, after the mitochondrial DNA (mtDNA) had been sequenced, several diseases resulting from mtDNA mutations emerged. Later, numerous disorders caused by mutations in the nuclear genes encoding mitochondrial proteins were found. A group of these diseases are due to defects of mitochondrial carriers, a family of proteins named solute carrier family 25 (SLC25), that transport a variety of solutes such as the reagents of ATP synthase (ATP, ADP, and phosphate), tricarboxylic acid cycle intermediates, cofactors, amino acids, and carnitine esters of fatty acids. The disease-causing mutations disclosed in mitochondrial carriers range from point mutations, which are often localized in the substrate translocation pore of the carrier, to large deletions and insertions. The biochemical consequences of deficient transport are the compartmentalized accumulation of the substrates and dysfunctional mitochondrial and cellular metabolism, which frequently develop into various forms of myopathy, encephalopathy, or neuropathy. Examples of diseases, due to mitochondrial carrier mutations are: combined D-2- and L-2-hydroxyglutaric aciduria, carnitine-acylcarnitine carrier deficiency, hyperornithinemia-hyperammonemia-homocitrillinuria (HHH) syndrome, early infantile epileptic encephalopathy type 3, Amish microcephaly, aspartate/glutamate isoform 1 deficiency, congenital sideroblastic anemia, Fontaine progeroid syndrome, and citrullinemia type II. Here, we review all the mitochondrial carrier-related diseases known until now, focusing on the connections between the molecular basis, altered metabolism, and phenotypes of these inherited disorders.
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Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
| | - Pasquale Scarcia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Department of Sciences, University of Basilicata, via Ateneo Lucano 10, 85100 Potenza, Italy
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
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22
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Van Veldhoven PP, de Schryver E, Young SG, Zwijsen A, Fransen M, Espeel M, Baes M, Van Ael E. Slc25a17 Gene Trapped Mice: PMP34 Plays a Role in the Peroxisomal Degradation of Phytanic and Pristanic Acid. Front Cell Dev Biol 2020; 8:144. [PMID: 32266253 PMCID: PMC7106852 DOI: 10.3389/fcell.2020.00144] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/20/2020] [Indexed: 12/04/2022] Open
Abstract
Mice lacking PMP34, a peroxisomal membrane transporter encoded by Slc25a17, did not manifest any obvious phenotype on a Swiss Webster genetic background, even with various treatments designed to unmask impaired peroxisomal functioning. Peroxisomal α- and β-oxidation rates in PMP34 deficient fibroblasts or liver slices were not or only modestly affected and in bile, no abnormal bile acid intermediates were detected. Peroxisomal content of cofactors like CoA, ATP, NAD+, thiamine-pyrophosphate and pyridoxal-phosphate, based on direct or indirect data, appeared normal as were tissue plasmalogen and very long chain fatty acid levels. However, upon dietary phytol administration, the knockout mice displayed hepatomegaly, liver inflammation, and an induction of peroxisomal enzymes. This phenotype was partially mediated by PPARα. Hepatic triacylglycerols and cholesterylesters were elevated and both phytanic acid and pristanic acid accumulated in the liver lipids, in females to higher extent than in males. In addition, pristanic acid degradation products were detected, as wells as the CoA-esters of all these branched fatty acids. Hence, PMP34 is important for the degradation of phytanic/pristanic acid and/or export of their metabolites. Whether this is caused by a shortage of peroxisomal CoA affecting the intraperoxisomal formation of pristanoyl-CoA (and perhaps of phytanoyl-CoA), or the SCPx-catalyzed thiolytic cleavage during pristanic acid β-oxidation, could not be proven in this model, but the phytol-derived acyl-CoA profile is compatible with the latter possibility. On the other hand, the normal functioning of other peroxisomal pathways, and especially bile acid formation, seems to exclude severe transport problems or a shortage of CoA, and other cofactors like FAD, NAD(P)+, TPP. Based on our findings, PMP34 deficiency in humans is unlikely to be a life threatening condition but could cause elevated phytanic/pristanic acid levels in older adults.
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Affiliation(s)
| | - Evelyn de Schryver
- LIPIT, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Stephen G. Young
- Departments of Medicine and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - An Zwijsen
- Laboratory of Developmental Signaling, Department Human Genetics, VIB-KU Leuven, Leuven, Belgium
| | - Marc Fransen
- LIPIT, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Marc Espeel
- Department of Anatomy, Embryology, Histology and Medical Physics, Ghent University, Ghent, Belgium
| | - Myriam Baes
- Laboratory of Cell Metabolism, Faculty of Pharmaceutical Sciences, KU Leuven, Leuven, Belgium
| | - Elke Van Ael
- LIPIT, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
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23
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Natarajan V, Chawla R, Mah T, Vivekanandan R, Tan SY, Sato PY, Mallilankaraman K. Mitochondrial Dysfunction in Age-Related Metabolic Disorders. Proteomics 2020; 20:e1800404. [PMID: 32131138 DOI: 10.1002/pmic.201800404] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 02/07/2020] [Indexed: 12/16/2022]
Abstract
Aging is a natural biological process in living organisms characterized by receding bioenergetics. Mitochondria are crucial for cellular bioenergetics and thus an important contributor to age-related energetics deterioration. In addition, mitochondria play a major role in calcium signaling, redox homeostasis, and thermogenesis making this organelle a major cellular component that dictates the fate of a cell. To maintain its quantity and quality, mitochondria undergo multiple processes such as fission, fusion, and mitophagy to eliminate or replace damaged mitochondria. While this bioenergetics machinery is properly protected, the functional decline associated with age and age-related metabolic diseases is mostly a result of failure in such protective mechanisms. In addition, metabolic by-products like reactive oxygen species also aid in this destructive pathway. Mitochondrial dysfunction has always been thought to be associated with diseases. Moreover, studies in recent years have pointed out that aging contributes to the decay of mitochondrial health by promoting imbalances in key mitochondrial-regulated pathways. Hence, it is crucial to understand the nexus of mitochondrial dysfunction in age-related diseases. This review focuses on various aspects of basic mitochondrial biology and its status in aging and age-related metabolic diseases.
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Affiliation(s)
- Venkateswaran Natarajan
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Ritu Chawla
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Tania Mah
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Rajesh Vivekanandan
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Shu Yi Tan
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Priscila Y Sato
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, 19102-1902, USA
| | - Karthik Mallilankaraman
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore.,Center for Healthy Longevity, National University Health System, Singapore, 119228, Singapore
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24
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Calbet JAL, Martín-Rodríguez S, Martin-Rincon M, Morales-Alamo D. An integrative approach to the regulation of mitochondrial respiration during exercise: Focus on high-intensity exercise. Redox Biol 2020; 35:101478. [PMID: 32156501 PMCID: PMC7284910 DOI: 10.1016/j.redox.2020.101478] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/20/2020] [Accepted: 02/23/2020] [Indexed: 12/14/2022] Open
Abstract
During exercise, muscle ATP demand increases with intensity, and at the highest power output, ATP consumption may increase more than 100-fold above the resting level. The rate of mitochondrial ATP production during exercise depends on the availability of O2, carbon substrates, reducing equivalents, ADP, Pi, free creatine, and Ca2+. It may also be modulated by acidosis, nitric oxide and reactive oxygen and nitrogen species (RONS). During fatiguing and repeated sprint exercise, RONS production may cause oxidative stress and damage to cellular structures and may reduce mitochondrial efficiency. Human studies indicate that the relatively low mitochondrial respiratory rates observed during sprint exercise are not due to lack of O2, or insufficient provision of Ca2+, reduced equivalents or carbon substrates, being a suboptimal stimulation by ADP the most plausible explanation. Recent in vitro studies with isolated skeletal muscle mitochondria, studied in conditions mimicking different exercise intensities, indicate that ROS production during aerobic exercise amounts to 1-2 orders of magnitude lower than previously thought. In this review, we will focus on the mechanisms regulating mitochondrial respiration, particularly during high-intensity exercise. We will analyze the factors that limit mitochondrial respiration and those that determine mitochondrial efficiency during exercise. Lastly, the differences in mitochondrial respiration between men and women will be addressed.
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Affiliation(s)
- Jose A L Calbet
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017, Las Palmas de Gran Canaria, Spain; Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Paseo Blas Cabrera Felipe "Físico" (s/n), 35017, Las Palmas de Gran Canaria, Canary Islands, Spain; Department of Physical Performance, The Norwegian School of Sport Sciences, Postboks, 4014 Ulleval Stadion, 0806 Oslo, Norway.
| | - Saúl Martín-Rodríguez
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017, Las Palmas de Gran Canaria, Spain; Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Paseo Blas Cabrera Felipe "Físico" (s/n), 35017, Las Palmas de Gran Canaria, Canary Islands, Spain
| | - Marcos Martin-Rincon
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017, Las Palmas de Gran Canaria, Spain; Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Paseo Blas Cabrera Felipe "Físico" (s/n), 35017, Las Palmas de Gran Canaria, Canary Islands, Spain
| | - David Morales-Alamo
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017, Las Palmas de Gran Canaria, Spain; Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Paseo Blas Cabrera Felipe "Físico" (s/n), 35017, Las Palmas de Gran Canaria, Canary Islands, Spain
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25
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The SLC25 Mitochondrial Carrier Family: Structure and Mechanism. Trends Biochem Sci 2019; 45:244-258. [PMID: 31787485 PMCID: PMC7611774 DOI: 10.1016/j.tibs.2019.11.001] [Citation(s) in RCA: 189] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/30/2019] [Accepted: 11/01/2019] [Indexed: 12/27/2022]
Abstract
Members of the mitochondrial carrier family (SLC25) provide the transport steps for amino acids, carboxylic acids, fatty acids, cofactors, inorganic ions, and nucleotides across the mitochondrial inner membrane and are crucial for many cellular processes. Here, we use new insights into the transport mechanism of the mitochondrial ADP/ATP carrier to examine the structure and function of other mitochondrial carriers. They all have a single substrate-binding site and two gates, which are present on either side of the membrane and involve salt-bridge networks. Transport is likely to occur by a common mechanism, in which the coordinated movement of six structural elements leads to the alternating opening and closing of the matrix or cytoplasmic side of the carriers.
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26
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Villalobo A, González-Muñoz M, Berchtold MW. Proteins with calmodulin-like domains: structures and functional roles. Cell Mol Life Sci 2019; 76:2299-2328. [PMID: 30877334 PMCID: PMC11105222 DOI: 10.1007/s00018-019-03062-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 02/26/2019] [Accepted: 03/07/2019] [Indexed: 12/21/2022]
Abstract
The appearance of modular proteins is a widespread phenomenon during the evolution of proteins. The combinatorial arrangement of different functional and/or structural domains within a single polypeptide chain yields a wide variety of activities and regulatory properties to the modular proteins. In this review, we will discuss proteins, that in addition to their catalytic, transport, structure, localization or adaptor functions, also have segments resembling the helix-loop-helix EF-hand motifs found in Ca2+-binding proteins, such as calmodulin (CaM). These segments are denoted CaM-like domains (CaM-LDs) and play a regulatory role, making these CaM-like proteins sensitive to Ca2+ transients within the cell, and hence are able to transduce the Ca2+ signal leading to specific cellular responses. Importantly, this arrangement allows to this group of proteins direct regulation independent of other Ca2+-sensitive sensor/transducer proteins, such as CaM. In addition, this review also covers CaM-binding proteins, in which their CaM-binding site (CBS), in the absence of CaM, is proposed to interact with other segments of the same protein denoted CaM-like binding site (CLBS). CLBS are important regulatory motifs, acting either by keeping these CaM-binding proteins inactive in the absence of CaM, enhancing the stability of protein complexes and/or facilitating their dimerization via CBS/CLBS interaction. The existence of proteins containing CaM-LDs or CLBSs substantially adds to the enormous versatility and complexity of Ca2+/CaM signaling.
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Affiliation(s)
- Antonio Villalobo
- Department of Cancer Biology, Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Arturo Duperier 4, 28029, Madrid, Spain.
- Instituto de Investigaciones Sanitarias, Hospital Universitario La Paz, Edificio IdiPAZ, Paseo de la Castellana 261, 28046, Madrid, Spain.
| | - María González-Muñoz
- Department of Cancer Biology, Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Arturo Duperier 4, 28029, Madrid, Spain
| | - Martin W Berchtold
- Department of Biology, University of Copenhagen, 13 Universitetsparken, 2100, Copenhagen, Denmark.
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27
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Calcium Deregulation and Mitochondrial Bioenergetics in GDAP1-Related CMT Disease. Int J Mol Sci 2019; 20:ijms20020403. [PMID: 30669311 PMCID: PMC6359725 DOI: 10.3390/ijms20020403] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/11/2019] [Accepted: 01/12/2019] [Indexed: 12/17/2022] Open
Abstract
The pathology of Charcot-Marie-Tooth (CMT), a disease arising from mutations in different genes, has been associated with an impairment of mitochondrial dynamics and axonal biology of mitochondria. Mutations in ganglioside-induced differentiation-associated protein 1 (GDAP1) cause several forms of CMT neuropathy, but the pathogenic mechanisms involved remain unclear. GDAP1 is an outer mitochondrial membrane protein highly expressed in neurons. It has been proposed to play a role in different aspects of mitochondrial physiology, including mitochondrial dynamics, oxidative stress processes, and mitochondrial transport along the axons. Disruption of the mitochondrial network in a neuroblastoma model of GDAP1-related CMT has been shown to decrease Ca2+ entry through the store-operated calcium entry (SOCE), which caused a failure in stimulation of mitochondrial respiration. In this review, we summarize the different functions proposed for GDAP1 and focus on the consequences for Ca2+ homeostasis and mitochondrial energy production linked to CMT disease caused by different GDAP1 mutations.
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28
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Juaristi I, Llorente-Folch I, Satrústegui J, Del Arco A. Extracellular ATP and glutamate drive pyruvate production and energy demand to regulate mitochondrial respiration in astrocytes. Glia 2019; 67:759-774. [PMID: 30623988 DOI: 10.1002/glia.23574] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/08/2018] [Accepted: 11/13/2018] [Indexed: 12/26/2022]
Abstract
Astrocytes respond to energetic demands by upregulating glycolysis, lactate production, and respiration. This study addresses the role of respiration and calcium regulation of respiration as part of the astrocyte response to the workloads caused by extracellular ATP and glutamate. Extracellular ATP (100 μM to 1 mM) causes a Ca2+ -dependent workload and fall of the cytosolic ATP/ADP ratio which acutely increases astrocytes respiration. Part of this increase is related to a Ca2+ -dependent upregulation of cytosolic pyruvate production. Conversely, glutamate (200 μM) causes a Na+ , but not Ca2+ , dependent workload even though glutamate-induced Ca2+ signals readily reach mitochondria. The glutamate workload triggers a rapid fall in the cytosolic ATP/ADP ratio and stimulation of respiration. These effects are mimicked by D-aspartate a nonmetabolized agonist of the glutamate transporter, but not by a metabotropic glutamate receptor agonist, indicating a major role of Na+ -dependent workload in stimulated respiration. Glutamate-induced increase in respiration is linked to a rapid increase in glycolytic pyruvate production, suggesting that both glutamate and extracellular ATP cause an increase in astrocyte respiration fueled by workload-induced increase in pyruvate production. However, glutamate-induced pyruvate production is partly resistant to glycolysis blockers (iodoacetate), indicating that oxidative consumption of glutamate also contributes to stimulated respiration. As stimulation of respiration by ATP and glutamate are similar and pyruvate production smaller in the first case, the results suggest that the response to extracellular ATP is a Ca2+ -dependent upregulation of respiration added to glycolysis upregulation. The global contribution of astrocyte respiratory responses to brain oxygen consumption is an open question.
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Affiliation(s)
- Inés Juaristi
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Irene Llorente-Folch
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland.,Center for Systems Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Araceli Del Arco
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.,Facultad de Ciencias Ambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla la Mancha, Toledo, Spain
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29
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Harborne SPD, Kunji ERS. Calcium-regulated mitochondrial ATP-Mg/P i carriers evolved from a fusion of an EF-hand regulatory domain with a mitochondrial ADP/ATP carrier-like domain. IUBMB Life 2018; 70:1222-1232. [PMID: 30281880 PMCID: PMC6283063 DOI: 10.1002/iub.1931] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/19/2018] [Accepted: 07/19/2018] [Indexed: 02/02/2023]
Abstract
The mitochondrial ATP-Mg/Pi carrier is responsible for the calcium-dependent regulation of adenosine nucleotide concentrations in the mitochondrial matrix, which allows mitochondria to respond to changing energy requirements of the cell. The carrier is expressed in mitochondria of fungi, plants and animals and belongs to the family of mitochondrial carriers. The carrier is unusual as it consists of three separate domains: (i) an N-terminal regulatory domain with four calcium-binding EF-hands similar to calmodulin, (ii) a loop domain containing an amphipathic α-helix and (iii) a mitochondrial carrier domain related to the mitochondrial ADP/ATP carrier. This striking example of three domains coming together from different origins to provide new functions represents an interesting quirk of evolution. In this review, we outline how the carrier was identified and how its physiological role was established with a focus on human isoforms. We exploit the sequence and structural information of the domains to explore the similarities and differences to their closest counterparts; mitochondrial ADP/ATP carriers and proteins with four EF-hands. We discuss how their combined function has led to a mechanism for calcium-regulated transport of adenosine nucleotides. Finally, we compare the ATP-Mg/Pi carrier with the mitochondrial aspartate/glutamate carrier, the only other mitochondrial carrier regulated by calcium, and we will argue that they have arisen by convergent rather than divergent evolution. © 2018 The Authors. IUBMB Life published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology, 70(12):1222-1232, 2018.
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Affiliation(s)
- Steven P. D. Harborne
- School of Biomedical Sciences and Astbury Centre for Structural Molecular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Edmund R. S. Kunji
- Medical Research Council Mitochondrial Biology UnitUniversity of CambridgeCambridgeCB2 0XYUK
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30
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Slavotinek A. Genetics of anophthalmia and microphthalmia. Part 2: Syndromes associated with anophthalmia-microphthalmia. Hum Genet 2018; 138:831-846. [PMID: 30374660 DOI: 10.1007/s00439-018-1949-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 10/20/2018] [Indexed: 12/12/2022]
Abstract
As new genes for A/M are identified in the genomic era, the number of syndromes associated with A/M has greatly expanded. In this review, we provide a brief synopsis of the clinical presentation and molecular genetic etiology of previously characterized pathways involved in A/M, including the Sex-determining region Y-box 2 (SOX2), Orthodenticle Homeobox 2 (OTX2) and Paired box protein-6 (PAX6) genes, and the Stimulated by retinoic acid gene 6 homolog (STRA6), Aldehyde Dehydrogenase 1 Family Member A3 (ALDH1A3), and RA Receptor Beta (RARβ) genes that are involved in retinoic acid synthesis. Less common genetic causes of A/M, including genes involved in BMP signaling [Bone Morphogenetic Protein 4 (BMP4), Bone Morphogenetic Protein 7 (BMP7) and SPARC-related modular calcium-binding protein 1 (SMOC1)], genes involved in the mitochondrial respiratory chain complex [Holocytochrome c-type synthase (HCCS), Cytochrome C Oxidase Subunit 7B (COX7B), and NADH:Ubiquinone Oxidoreductase subunit B11 (NDUFB11)], the BCL-6 corepressor gene (BCOR), Yes-Associated Protein 1 (YAP1) and Transcription Factor AP-2 Alpha (TFAP2α), are more briefly discussed. We also review several recently described genes and pathways associated with A/M, including Smoothened (SMO) that is involved in Sonic hedgehog (SHH) signaling, Structural maintenance of chromosomes flexible hinge domain containing 1 (SMCHD1) and Solute carrier family 25 member 24 (SLC25A24), emphasizing phenotype-genotype correlations and shared pathways where relevant.
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Affiliation(s)
- Anne Slavotinek
- Division of Genetics, Department of Pediatrics, University of California, San Francisco Room RH384C, 1550 4th St, San Francisco, CA, 94143-2711, USA.
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31
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Rossi A, Pizzo P, Filadi R. Calcium, mitochondria and cell metabolism: A functional triangle in bioenergetics. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1866:1068-1078. [PMID: 30982525 DOI: 10.1016/j.bbamcr.2018.10.016] [Citation(s) in RCA: 251] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/19/2018] [Accepted: 10/21/2018] [Indexed: 12/18/2022]
Abstract
The versatility of mitochondrial metabolism and its fine adjustments to specific physiological or pathological conditions regulate fundamental cell pathways, ranging from proliferation to apoptosis. In particular, Ca2+ signalling has emerged as a key player exploited by mitochondria to tune their activity according with cell demand. The functional interaction between mitochondria and endoplasmic reticulum (ER) deeply impacts on the correct mitochondrial Ca2+ signal, thus modulating cell bioenergetics and functionality. Indeed, Ca2+ released by the ER is taken up by mitochondria where, both in the intermembrane space and in the matrix, it regulates the activity of transporters, enzymes and proteins involved in organelles' metabolism. In this review, we will briefly summarize Ca2+-dependent mechanisms involved in the regulation of mitochondrial activity. Moreover, we will discuss some recent reports, in which alterations in mitochondrial Ca2+ signalling have been associated with specific pathological conditions, such as neurodegeneration and cancer.
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Affiliation(s)
- Alice Rossi
- Department of Biomedical Sciences, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy; Neuroscience Institute - Italian National Research Council (CNR), 35131 Padova, Italy.
| | - Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, Via U. Bassi 58/B, 35131 Padova, Italy
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32
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Rodríguez-García ME, Cotrina-Vinagre FJ, Cruz-Rojo J, Garzón-Lorenzo L, Carnicero-Rodríguez P, Pozo JSD, Martínez-Azorín F. A rare male patient with Fontaine progeroid syndrome caused by p.R217H de novo mutation in SLC25A24. Am J Med Genet A 2018; 176:2479-2486. [DOI: 10.1002/ajmg.a.40496] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/09/2018] [Accepted: 07/14/2018] [Indexed: 01/09/2023]
Affiliation(s)
- María Elena Rodríguez-García
- Laboratorio de Enfermedades Mitocondriales; Instituto de Investigación Hospital 12 de Octubre (i+12); Madrid Spain
| | | | - Jaime Cruz-Rojo
- Unidad de Dismorfología, Departamento de Pediatría; Hospital 12 de Octubre; Madrid Spain
| | - Lucía Garzón-Lorenzo
- Unidad de Dismorfología, Departamento de Pediatría; Hospital 12 de Octubre; Madrid Spain
| | - Patricia Carnicero-Rodríguez
- Laboratorio de Enfermedades Mitocondriales; Instituto de Investigación Hospital 12 de Octubre (i+12); Madrid Spain
| | - Jaime Sánchez-Del Pozo
- Unidad de Dismorfología, Departamento de Pediatría; Hospital 12 de Octubre; Madrid Spain
| | - Francisco Martínez-Azorín
- Laboratorio de Enfermedades Mitocondriales; Instituto de Investigación Hospital 12 de Octubre (i+12); Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Madrid Spain
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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: 505] [Impact Index Per Article: 84.2] [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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34
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Filadi R, Basso E, Lefkimmiatis K, Pozzan T. Beyond Intracellular Signaling: The Ins and Outs of Second Messengers Microdomains. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 981:279-322. [PMID: 29594866 DOI: 10.1007/978-3-319-55858-5_12] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A typical characteristic of eukaryotic cells compared to prokaryotes is represented by the spatial heterogeneity of the different structural and functional components: for example, most of the genetic material is surrounded by a highly specific membrane structure (the nuclear membrane), continuous with, yet largely different from, the endoplasmic reticulum (ER); oxidative phosphorylation is carried out by organelles enclosed by a double membrane, the mitochondria; in addition, distinct domains, enriched in specific proteins, are present in the plasma membrane (PM) of most cells. Less obvious, but now generally accepted, is the notion that even the concentration of small molecules such as second messengers (Ca2+ and cAMP in particular) can be highly heterogeneous within cells. In the case of most organelles, the differences in the luminal levels of second messengers depend either on the existence on their membrane of proteins that allow the accumulation/release of the second messenger (e.g., in the case of Ca2+, pumps, exchangers or channels), or on the synthesis and degradation of the specific molecule within the lumen (the autonomous intramitochondrial cAMP system). It needs stressing that the existence of a surrounding membrane does not necessarily imply the existence of a gradient between the cytosol and the organelle lumen. For example, the nuclear membrane is highly permeable to both Ca2+ and cAMP (nuclear pores are permeable to solutes up to 50 kDa) and differences in [Ca2+] or [cAMP] between cytoplasm and nucleoplasm are not seen in steady state and only very transiently during cell activation. A similar situation has been observed, as far as Ca2+ is concerned, in peroxisomes.
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Affiliation(s)
- Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Emy Basso
- Institute of Neuroscience, Padova Section, National Research Council, Padova, Italy
| | - Konstantinos Lefkimmiatis
- Institute of Neuroscience, Padova Section, National Research Council, Padova, Italy
- Venetian Institute of Molecular Medicine, Padova, Italy
| | - Tullio Pozzan
- Department of Biomedical Sciences, University of Padova, Padova, Italy.
- Institute of Neuroscience, Padova Section, National Research Council, Padova, Italy.
- Venetian Institute of Molecular Medicine, Padova, Italy.
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35
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Hofherr A, Seger C, Fitzpatrick F, Busch T, Michel E, Luan J, Osterried L, Linden F, Kramer-Zucker A, Wakimoto B, Schütze C, Wiedemann N, Artati A, Adamski J, Walz G, Kunji ERS, Montell C, Watnick T, Köttgen M. The mitochondrial transporter SLC25A25 links ciliary TRPP2 signaling and cellular metabolism. PLoS Biol 2018; 16:e2005651. [PMID: 30080851 PMCID: PMC6095617 DOI: 10.1371/journal.pbio.2005651] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 08/16/2018] [Accepted: 07/27/2018] [Indexed: 02/02/2023] Open
Abstract
Cilia are organelles specialized in movement and signal transduction. The ciliary transient receptor potential ion channel polycystin-2 (TRPP2) controls elementary cilia-mediated physiological functions ranging from male fertility and kidney development to left-right patterning. However, the molecular components translating TRPP2 channel-mediated Ca2+ signals into respective physiological functions are unknown. Here, we show that the Ca2+-regulated mitochondrial ATP-Mg/Pi solute carrier 25 A 25 (SLC25A25) acts downstream of TRPP2 in an evolutionarily conserved metabolic signaling pathway. We identify SLC25A25 as an essential component in this cilia-dependent pathway using a genome-wide forward genetic screen in Drosophila melanogaster, followed by a targeted analysis of SLC25A25 function in zebrafish left-right patterning. Our data suggest that TRPP2 ion channels regulate mitochondrial SLC25A25 transporters via Ca2+ establishing an evolutionarily conserved molecular link between ciliary signaling and mitochondrial metabolism.
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Affiliation(s)
- Alexis Hofherr
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg im Breisgau, Germany
- Faculty of Biology, University of Freiburg, Freiburg im Breisgau, Germany
| | - Claudia Seger
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Fiona Fitzpatrick
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Tilman Busch
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Elisabeth Michel
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Jingting Luan
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Lea Osterried
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Frieder Linden
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Albrecht Kramer-Zucker
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Barbara Wakimoto
- Department of Biology, University of Washington, Seattle, Washington, United States of America
| | - Conny Schütze
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Nils Wiedemann
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg im Breisgau, Germany
| | - Anna Artati
- Institute of Experimental Genetics, Genome Analysis Center, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Jerzy Adamski
- Institute of Experimental Genetics, Genome Analysis Center, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Lehrstuhl für Experimentelle Genetik, Technische Universität München, Freising-Weihenstephan, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Gerd Walz
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg im Breisgau, Germany
| | - Edmund R. S. Kunji
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Craig Montell
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Terry Watnick
- Division of Nephrology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Michael Köttgen
- Renal Division, Department of Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
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36
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Mitochondrial dysfunction induced by leflunomide and its active metabolite. Toxicology 2018; 396-397:33-45. [PMID: 29427785 DOI: 10.1016/j.tox.2018.02.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/24/2018] [Accepted: 02/05/2018] [Indexed: 12/15/2022]
Abstract
Leflunomide, an anti-inflammatory drug used for the treatment of rheumatoid arthritis, has been marked with a black box warning regarding an increased risk of liver injury. The active metabolite of leflunomide, A771726, which also carries a boxed warning about potential hepatotoxicity, has been marketed as teriflunomide for the treatment of relapsing multiple sclerosis. Thus far, however, the mechanism of liver injury associated with the two drugs has remained elusive. In this study, cytotoxicity assays showed that ATP depletion and subsequent LDH release were induced in a time- and concentration-dependent manner by leflunomide in HepG2 cells, and to a lesser extent, by A77 1726. The decline of cellular ATP levels caused by leflunomide was dramatically exacerbated when galactose was substituted for glucose as the sugar source, indicating a potential mitochondrial liability of leflunomide. By measuring the activities of immuno-captured mitochondrial oxidative phosphorylation (OXPHOS) complexes, we found that leflunomide and A77 1726 preferentially targeted complex V (F1FO ATP synthase), with IC50 values of 35.0 and 63.7 μM, respectively. Bongkrekic acid, a mitochondrial permeability transition pore blocker that targets adenine nucleotide translocase, profoundly attenuated mitochondrial membrane depolarization, ATP depletion, and LDH leakage induced by leflunomide and A77 1726. Substantial alterations of mitochondrial function at the transcript level were observed in leflunomide-treated HepG2 cells, whereas the effects of A77 1726 on the cellular transcriptome were much less profound. Our results suggest that mitochondrial dysfunction may be implicated in the hepatotoxicity associated with leflunomide and A77 1726, with the former exhibiting higher toxicity potency.
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37
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Writzl K, Maver A, Kovačič L, Martinez-Valero P, Contreras L, Satrustegui J, Castori M, Faivre L, Lapunzina P, van Kuilenburg ABP, Radović S, Thauvin-Robinet C, Peterlin B, Del Arco A, Hennekam RC. De Novo Mutations in SLC25A24 Cause a Disorder Characterized by Early Aging, Bone Dysplasia, Characteristic Face, and Early Demise. Am J Hum Genet 2017; 101:844-855. [PMID: 29100094 PMCID: PMC5673633 DOI: 10.1016/j.ajhg.2017.09.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/19/2017] [Indexed: 12/21/2022] Open
Abstract
A series of simplex cases have been reported under various diagnoses sharing early aging, especially evident in congenitally decreased subcutaneous fat tissue and sparse hair, bone dysplasia of the skull and fingers, a distinctive facial gestalt, and prenatal and postnatal growth retardation. For historical reasons, we suggest naming the entity Fontaine syndrome. Exome sequencing of four unrelated affected individuals showed that all carried the de novo missense variant c.649C>T (p.Arg217Cys) or c.650G>A (p.Arg217His) in SLC25A24, a solute carrier 25 family member coding for calcium-binding mitochondrial carrier protein (SCaMC-1, also known as SLC25A24). SLC25A24 allows an electro-neutral and reversible exchange of ATP-Mg and phosphate between the cytosol and mitochondria, which is required for maintaining optimal adenine nucleotide levels in the mitochondrial matrix. Molecular dynamic simulation studies predict that p.Arg217Cys and p.Arg217His narrow the substrate cavity of the protein and disrupt transporter dynamics. SLC25A24-mutant fibroblasts and cells expressing p.Arg217Cys or p.Arg217His variants showed altered mitochondrial morphology, a decreased proliferation rate, increased mitochondrial membrane potential, and decreased ATP-linked mitochondrial oxygen consumption. The results suggest that the SLC25A24 mutations lead to impaired mitochondrial ATP synthesis and cause hyperpolarization and increased proton leak in association with an impaired energy metabolism. Our findings identify SLC25A24 mutations affecting codon 217 as the underlying genetic cause of human progeroid Fontaine syndrome.
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Affiliation(s)
- Karin Writzl
- Clinical Institute of Medical Genetics, University Medical Centre, 1000 Ljubljana, Slovenia.
| | - Ales Maver
- Clinical Institute of Medical Genetics, University Medical Centre, 1000 Ljubljana, Slovenia
| | - Lidija Kovačič
- Novartis Ireland Ltd., Novartis, Vista Building, Elm Business Park, D04A9N6 Dublin 4, Ireland
| | - Paula Martinez-Valero
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid and Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Diaz, 28049 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, 28049 Madrid, Spain
| | - Laura Contreras
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid and Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Diaz, 28049 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, 28049 Madrid, Spain
| | - Jorgina Satrustegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid and Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Diaz, 28049 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, 28049 Madrid, Spain
| | - Marco Castori
- Division of Medical Genetics, Casa Sollievo della Sofferenza, Istituto di Ricovero e Cura a Carattere Scientifico, 71013 San Giovanni Rotondo, Foggia, Italy
| | - Laurence Faivre
- Centre de Référence Maladies Rares "cAnomalies du Développement et Syndromes Malformatifsc," Centre de Génétique, FHU-TRANSLAD, Hôpital d'Enfants, Centre Hospitalier Universitaire Dijon Bourgogne, 21079 Dijon, France; UMR 1231, Génétique des Anomalies du Développement, INSERM, Université de Bourgogne Franche-Comté, 21079 Dijon, France
| | - Pablo Lapunzina
- Instituto de Genética Médica y Molecular-IdiPAZ, Hospital Universitario La Paz, Centro de Investigación Biomédica en Red de Enfermedades Raras, 261-28046 Madrid, Spain
| | - André B P van Kuilenburg
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | | | - Christel Thauvin-Robinet
- Centre de Référence Maladies Rares "cAnomalies du Développement et Syndromes Malformatifsc," Centre de Génétique, FHU-TRANSLAD, Hôpital d'Enfants, Centre Hospitalier Universitaire Dijon Bourgogne, 21079 Dijon, France; UMR 1231, Génétique des Anomalies du Développement, INSERM, Université de Bourgogne Franche-Comté, 21079 Dijon, France
| | - Borut Peterlin
- Clinical Institute of Medical Genetics, University Medical Centre, 1000 Ljubljana, Slovenia
| | - Araceli Del Arco
- Instituto de Investigación Sanitaria Fundación Jiménez Diaz, 28049 Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, 28049 Madrid, Spain; Facultad de Ciencias Ambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla la Mancha, 45071-Toledo, Spain
| | - Raoul C Hennekam
- Department of Pediatrics, Academic Medical Center, University of Amsterdam, 1105AZ Amsterdam, the Netherlands
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38
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Ehmke N, Graul-Neumann L, Smorag L, Koenig R, Segebrecht L, Magoulas P, Scaglia F, Kilic E, Hennig AF, Adolphs N, Saha N, Fauler B, Kalscheuer VM, Hennig F, Altmüller J, Netzer C, Thiele H, Nürnberg P, Yigit G, Jäger M, Hecht J, Krüger U, Mielke T, Krawitz PM, Horn D, Schuelke M, Mundlos S, Bacino CA, Bonnen PE, Wollnik B, Fischer-Zirnsak B, Kornak U. De Novo Mutations in SLC25A24 Cause a Craniosynostosis Syndrome with Hypertrichosis, Progeroid Appearance, and Mitochondrial Dysfunction. Am J Hum Genet 2017; 101:833-843. [PMID: 29100093 DOI: 10.1016/j.ajhg.2017.09.016] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/19/2017] [Indexed: 12/28/2022] Open
Abstract
Gorlin-Chaudhry-Moss syndrome (GCMS) is a dysmorphic syndrome characterized by coronal craniosynostosis and severe midface hypoplasia, body and facial hypertrichosis, microphthalmia, short stature, and short distal phalanges. Variable lipoatrophy and cutis laxa are the basis for a progeroid appearance. Using exome and genome sequencing, we identified the recurrent de novo mutations c.650G>A (p.Arg217His) and c.649C>T (p.Arg217Cys) in SLC25A24 in five unrelated girls diagnosed with GCMS. Two of the girls had pronounced neonatal progeroid features and were initially diagnosed with Wiedemann-Rautenstrauch syndrome. SLC25A24 encodes a mitochondrial inner membrane ATP-Mg/Pi carrier. In fibroblasts from affected individuals, the mutated SLC25A24 showed normal stability. In contrast to control cells, the probands' cells showed mitochondrial swelling, which was exacerbated upon treatment with hydrogen peroxide (H2O2). The same effect was observed after overexpression of the mutant cDNA. Under normal culture conditions, the mitochondrial membrane potential of the probands' fibroblasts was intact, whereas ATP content in the mitochondrial matrix was lower than that in control cells. However, upon H2O2 exposure, the membrane potential was significantly elevated in cells harboring the mutated SLC25A24. No reduction of mitochondrial DNA copy number was observed. These findings demonstrate that mitochondrial dysfunction with increased sensitivity to oxidative stress is due to the SLC25A24 mutations. Our results suggest that the SLC25A24 mutations induce a gain of pathological function and link mitochondrial ATP-Mg/Pi transport to the development of skeletal and connective tissue.
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39
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Morris G, Walder K, McGee SL, Dean OM, Tye SJ, Maes M, Berk M. A model of the mitochondrial basis of bipolar disorder. Neurosci Biobehav Rev 2017; 74:1-20. [DOI: 10.1016/j.neubiorev.2017.01.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 01/08/2017] [Accepted: 01/10/2017] [Indexed: 12/11/2022]
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40
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González-Sánchez P, Pla-Martín D, Martínez-Valero P, Rueda CB, Calpena E, Del Arco A, Palau F, Satrústegui J. CMT-linked loss-of-function mutations in GDAP1 impair store-operated Ca 2+ entry-stimulated respiration. Sci Rep 2017; 7:42993. [PMID: 28220846 PMCID: PMC5318958 DOI: 10.1038/srep42993] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 01/18/2017] [Indexed: 12/18/2022] Open
Abstract
GDAP1 is an outer mitochondrial membrane protein involved in Charcot-Marie-Tooth (CMT) disease. Lack of GDAP1 gives rise to altered mitochondrial networks and endoplasmic reticulum (ER)-mitochondrial interactions resulting in a decreased ER-Ca2+ levels along with a defect on store-operated calcium entry (SOCE) related to a misallocation of mitochondria to subplasmalemmal sites. The defect on SOCE is mimicked by MCU silencing or mitochondrial depolarization, which prevent mitochondrial calcium uptake. Ca2+ release from de ER and Ca2+ inflow through SOCE in neuroblastoma cells result in a Ca2+-dependent upregulation of respiration which is blunted in GDAP1 silenced cells. Reduced SOCE in cells with CMT recessive missense mutations in the α-loop of GDAP1, but not dominant mutations, was associated with smaller SOCE-stimulated respiration. These cases of GDAP1 deficiency also resulted in a decreased ER-Ca2+ levels which may have pathological implications. The results suggest that CMT neurons may be under energetic constraints upon stimulation by Ca2+ mobilization agonists and point to a potential role of perturbed mitochondria-ER interaction related to energy metabolism in forms of CMT caused by some of the recessive or null mutations of GDAP1.
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Affiliation(s)
- Paloma González-Sánchez
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz, IIS-FJD, Madrid, 28040, Spain
| | - David Pla-Martín
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, 46012, Spain
| | - Paula Martínez-Valero
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz, IIS-FJD, Madrid, 28040, Spain
| | - Carlos B Rueda
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz, IIS-FJD, Madrid, 28040, Spain
| | - Eduardo Calpena
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, 46012, Spain
| | - Araceli Del Arco
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz, IIS-FJD, Madrid, 28040, Spain.,Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla la Mancha, Toledo, 45071, Spain
| | - Francesc Palau
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Program in Rare and Genetic Diseases and IBV/CSIC Associated Unit, Centro de Investigación Príncipe Felipe, Valencia, 46012, Spain.,Institut de Recerca Sant Joan de Déu and Hospital Sant Joan de Déu, Barcelona 08950, Spain.,Pediatrics Division, University of Barcelona School of Medicine, Barcelona, Spain
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz, IIS-FJD, Madrid, 28040, Spain
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41
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Filadi R, Theurey P, Pizzo P. The endoplasmic reticulum-mitochondria coupling in health and disease: Molecules, functions and significance. Cell Calcium 2017; 62:1-15. [PMID: 28108029 DOI: 10.1016/j.ceca.2017.01.003] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/09/2017] [Accepted: 01/09/2017] [Indexed: 12/14/2022]
Abstract
The close apposition between endoplasmic reticulum (ER) and mitochondria represents a key platform, capable to regulate different fundamental cellular pathways. Among these, Ca2+ signaling and lipid homeostasis have been demonstrated over the last years to be deeply modulated by ER-mitochondria cross-talk. Given its importance in cell life/death decisions, increasing evidence suggests that alterations of the ER-mitochondria axis could be responsible for the onset and progression of several diseases, including neurodegeneration, cancer and obesity. However, the molecular identity of the proteins controlling this inter-organelle apposition is still debated. In this review, we summarize the main cellular pathways controlled by ER-mitochondria appositions, focusing on the principal molecules reported to be involved in this interplay and on those diseases for which alterations in organelles communication have been reported.
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Affiliation(s)
- Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, Italy
| | - Pierre Theurey
- Department of Biomedical Sciences, University of Padova, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, Italy; Neuroscience Institute, National Research Council (CNR), Padova, Italy.
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42
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Maldonado EN, DeHart DN, Patnaik J, Klatt SC, Gooz MB, Lemasters JJ. ATP/ADP Turnover and Import of Glycolytic ATP into Mitochondria in Cancer Cells Is Independent of the Adenine Nucleotide Translocator. J Biol Chem 2016; 291:19642-50. [PMID: 27458020 DOI: 10.1074/jbc.m116.734814] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Indexed: 11/06/2022] Open
Abstract
Non-proliferating cells oxidize respiratory substrates in mitochondria to generate a protonmotive force (Δp) that drives ATP synthesis. The mitochondrial membrane potential (ΔΨ), a component of Δp, drives release of mitochondrial ATP(4-) in exchange for cytosolic ADP(3-) via the electrogenic adenine nucleotide translocator (ANT) located in the mitochondrial inner membrane, which leads to a high cytosolic ATP/ADP ratio up to >100-fold greater than matrix ATP/ADP. In rat hepatocytes, ANT inhibitors, bongkrekic acid (BA), and carboxyatractyloside (CAT), and the F1FO-ATP synthase inhibitor, oligomycin (OLIG), inhibited ureagenesis-induced respiration. However, in several cancer cell lines, OLIG but not BA and CAT inhibited respiration. In hepatocytes, respiratory inhibition did not collapse ΔΨ until OLIG, BA, or CAT was added. Similarly, in cancer cells OLIG and 2-deoxyglucose, a glycolytic inhibitor, depolarized mitochondria after respiratory inhibition, which showed that mitochondrial hydrolysis of glycolytic ATP maintained ΔΨ in the absence of respiration in all cell types studied. However in cancer cells, BA, CAT, and knockdown of the major ANT isoforms, ANT2 and ANT3, did not collapse ΔΨ after respiratory inhibition. These findings indicated that ANT was not mediating mitochondrial ATP/ADP exchange in cancer cells [corrected]. We propose that suppression of ANT contributes to low cytosolic ATP/ADP, activation of glycolysis, and a Warburg metabolic phenotype in proliferating cells.
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Affiliation(s)
- Eduardo N Maldonado
- From the Center for Cell Death, Injury, and Regeneration, Departments of Drug Discovery and Biomedical Sciences and the Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - David N DeHart
- Departments of Drug Discovery and Biomedical Sciences and
| | - Jyoti Patnaik
- Departments of Drug Discovery and Biomedical Sciences and
| | - Sandra C Klatt
- Departments of Drug Discovery and Biomedical Sciences and
| | | | - John J Lemasters
- From the Center for Cell Death, Injury, and Regeneration, Departments of Drug Discovery and Biomedical Sciences and the Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina 29425 and Biochemistry and Molecular Biology, and the Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russian Federation 142290
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43
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Wagner S, De Bortoli S, Schwarzländer M, Szabò I. Regulation of mitochondrial calcium in plants versus animals. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3809-29. [PMID: 27001920 DOI: 10.1093/jxb/erw100] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Ca(2+) acts as an important cellular second messenger in eukaryotes. In both plants and animals, a wide variety of environmental and developmental stimuli trigger Ca(2+) transients of a specific signature that can modulate gene expression and metabolism. In animals, mitochondrial energy metabolism has long been considered a hotspot of Ca(2+) regulation, with a range of pathophysiology linked to altered Ca(2+) control. Recently, several molecular players involved in mitochondrial Ca(2+) signalling have been identified, including those of the mitochondrial Ca(2+) uniporter. Despite strong evidence for sophisticated Ca(2+) regulation in plant mitochondria, the picture has remained much less clear. This is currently changing aided by live imaging and genetic approaches which allow dissection of subcellular Ca(2+) dynamics and identification of the proteins involved. We provide an update on our current understanding in the regulation of mitochondrial Ca(2+) and signalling by comparing work in plants and animals. The significance of mitochondrial Ca(2+) control is discussed in the light of the specific metabolic and energetic needs of plant and animal cells.
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Affiliation(s)
- Stephan Wagner
- Plant Energy Biology Lab, Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Friedrich-Ebert-Allee 144, D-53113 Bonn, Germany
| | - Sara De Bortoli
- Department of Biology and CNR Institute of Neurosciences, University of Padova, Viale G. Colombo 3, 35121 Padova, Italy
| | - Markus Schwarzländer
- Plant Energy Biology Lab, Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Friedrich-Ebert-Allee 144, D-53113 Bonn, Germany
| | - Ildikò Szabò
- Department of Biology and CNR Institute of Neurosciences, University of Padova, Viale G. Colombo 3, 35121 Padova, Italy
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44
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Llorente-Folch I, Rueda CB, Pardo B, Szabadkai G, Duchen MR, Satrustegui J. The regulation of neuronal mitochondrial metabolism by calcium. J Physiol 2016; 593:3447-62. [PMID: 25809592 DOI: 10.1113/jp270254] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/18/2015] [Indexed: 12/24/2022] Open
Abstract
Calcium signalling is fundamental to the function of the nervous system, in association with changes in ionic gradients across the membrane. Although restoring ionic gradients is energetically costly, a rise in intracellular Ca(2+) acts through multiple pathways to increase ATP synthesis, matching energy supply to demand. Increasing cytosolic Ca(2+) stimulates metabolite transfer across the inner mitochondrial membrane through activation of Ca(2+) -regulated mitochondrial carriers, whereas an increase in matrix Ca(2+) stimulates the citric acid cycle and ATP synthase. The aspartate-glutamate exchanger Aralar/AGC1 (Slc25a12), a component of the malate-aspartate shuttle (MAS), is stimulated by modest increases in cytosolic Ca(2+) and upregulates respiration in cortical neurons by enhancing pyruvate supply into mitochondria. Failure to increase respiration in response to small (carbachol) and moderate (K(+) -depolarization) workloads and blunted stimulation of respiration in response to high workloads (veratridine) in Aralar/AGC1 knockout neurons reflect impaired MAS activity and limited mitochondrial pyruvate supply. In response to large workloads (veratridine), acute stimulation of respiration occurs in the absence of MAS through Ca(2+) influx through the mitochondrial calcium uniporter (MCU) and a rise in matrix [Ca(2+) ]. Although the physiological importance of the MCU complex in work-induced stimulation of respiration of CNS neurons is not yet clarified, abnormal mitochondrial Ca(2+) signalling causes pathology. Indeed, loss of function mutations in MICU1, a regulator of MCU complex, are associated with neuromuscular disease. In patient-derived MICU1 deficient fibroblasts, resting matrix Ca(2+) is increased and mitochondria fragmented. Thus, the fine tuning of Ca(2+) signals plays a key role in shaping mitochondrial bioenergetics.
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Affiliation(s)
- I Llorente-Folch
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid-(CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz IIS-FJD, Madrid, Spain
| | - C B Rueda
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid-(CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz IIS-FJD, Madrid, Spain
| | - B Pardo
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid-(CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz IIS-FJD, Madrid, Spain
| | - G Szabadkai
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research, University College London, London, UK.,Department of Biomedical Sciences, University of Padua and Consiglio Nazionale delle Ricerche Neuroscience Institute, Padua, Italy
| | - M R Duchen
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research, University College London, London, UK
| | - J Satrustegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid-(CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz IIS-FJD, Madrid, Spain
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Abstract
In the last 5 years, most of the molecules that control mitochondrial Ca(2+) homeostasis have been finally identified. Mitochondrial Ca(2+) uptake is mediated by the Mitochondrial Calcium Uniporter (MCU) complex, a macromolecular structure that guarantees Ca(2+) accumulation inside mitochondrial matrix upon increases in cytosolic Ca(2+). Conversely, Ca(2+) release is under the control of the Na(+)/Ca(2+) exchanger, encoded by the NCLX gene, and of a H(+)/Ca(2+) antiporter, whose identity is still debated. The low affinity of the MCU complex, coupled to the activity of the efflux systems, protects cells from continuous futile cycles of Ca(2+) across the inner mitochondrial membrane and consequent massive energy dissipation. In this review, we discuss the basic principles that govern mitochondrial Ca(2+) homeostasis and the methods used to investigate the dynamics of Ca(2+) concentration within the organelles. We discuss the functional and structural role of the different molecules involved in mitochondrial Ca(2+) handling and their pathophysiological role.
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Affiliation(s)
- Diego De Stefani
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy; , ,
| | - Rosario Rizzuto
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy; , , .,National Research Council (CNR) Neuroscience Institute, 35121 Padova, Italy
| | - Tullio Pozzan
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy; , , .,National Research Council (CNR) Neuroscience Institute, 35121 Padova, Italy.,Venetian Institute of Molecular Medicine, 35121 Padova, Italy
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46
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Del Arco A, Contreras L, Pardo B, Satrustegui J. Calcium regulation of mitochondrial carriers. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2413-21. [PMID: 27033520 DOI: 10.1016/j.bbamcr.2016.03.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/23/2016] [Accepted: 03/23/2016] [Indexed: 11/16/2022]
Abstract
Mitochondrial function is regulated by calcium. In addition to the long known effects of matrix Ca(2+), regulation of metabolite transport by extramitochondrial Ca(2+) represents an alternative Ca(2+)-dependent mechanism to regulate mitochondrial function. The Ca(2+) regulated mitochondrial transporters (CaMCs) are well suited for that role, as they contain long N-terminal extensions harboring EF-hand Ca(2+) binding domains facing the intermembrane space. They fall in two groups, the aspartate/glutamate exchangers, AGCs, major components of the NADH malate aspartate shuttle (MAS) and urea cycle, and the ATP-Mg(2+)/Pi exchangers or short CaMCs (APCs or SCaMCs). The AGCs are activated by relatively low Ca(2+) levels only slightly higher than resting Ca(2+), whereas all SCaMCs studied so far require strong Ca(2+) signals, above micromolar, for activation. In addition, AGCs are not strictly Ca(2+) dependent, being active even in Ca(2+)-free conditions. Thus, AGCs are well suited to respond to small Ca(2+) signals and that do not reach mitochondria. In contrast, ATP-Mg(2+)/Pi carriers are inactive in Ca(2+) free conditions and activation requires Ca(2+) signals that will also activate the calcium uniporter (MCU). By changing the net content of adenine nucleotides of the matrix upon activation, SCaMCs regulate the activity of the permeability transition pore, and the Ca(2+) retention capacity of mitochondria (CRC), two functions synergizing with those of the MCU. The different Ca(2+) activation properties of the two CaMCs are discussed in relation to their newly obtained structures. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
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Affiliation(s)
- Araceli Del Arco
- Facultad de Ciencias Ambientales y Bioquímica, Centro RegionaI de Investigaciones Biomédicas, Universidad de Castilla la Mancha, Toledo 45071, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Laura Contreras
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Beatriz Pardo
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Jorgina Satrustegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.
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47
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Martín-Maestro P, Gargini R, Perry G, Avila J, García-Escudero V. PARK2 enhancement is able to compensate mitophagy alterations found in sporadic Alzheimer's disease. Hum Mol Genet 2015; 25:792-806. [PMID: 26721933 DOI: 10.1093/hmg/ddv616] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 12/17/2015] [Indexed: 02/04/2023] Open
Abstract
Mitochondrial anomalies have been previously reported in patients' brain and peripheral tissue, suggesting their relevance in sporadic Alzheimer's disease (AD). The present work evaluates mitochondrial function and recycling in human fibroblasts and brain biopsies. Functional studies using patients' skin fibroblasts showed slower mitochondrial membrane potential recovery after a mitochondrial insult together with alterations in lysosomes and autophagy, accompanied by an increase of oxidized and ubiquitinated proteins. Impairment in mitophagy has been proven in these cells due to diminished PARK2 and insufficient vesicle induction, accumulating depolarized mitochondria and PINK1. Augmented Δ1 PINK1 fragment levels suggest an inhibitory effect over PARK2 translocation to the mitochondria, causing the accumulation of activated PINK1. Moreover, the overexpression of PARK2 diminished ubiquitinated proteins accumulation, improves its targeting to mitochondria and potentiates autophagic vesicle synthesis. This allows the reversion of mitophagy failure reflected in the recovery of membrane potential and the decrease of PINK1 and mitochondria accumulation. Sporadic AD fibroblasts exhibited alterations similar to what it could be found in patients' hippocampal samples at early stages of the disease, where there was an accumulation of PINK1 and Δ1 PINK1 together with abnormally increased mitochondrial content. Our findings indicate that mitophagy alterations can be considered a new hallmark of sporadic AD and validate the use of fibroblasts for modelling this pathology.
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Affiliation(s)
- Patricia Martín-Maestro
- Centro de Biología Molecular 'Severo Ochoa' (UAM-CSIC), Nicolás Cabrera, 1. Cantoblanco, 28049 Madrid, Spain, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Valderrebollo, 5, 28031 Madrid, Spain
| | - Ricardo Gargini
- Centro de Biología Molecular 'Severo Ochoa' (UAM-CSIC), Nicolás Cabrera, 1. Cantoblanco, 28049 Madrid, Spain, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Valderrebollo, 5, 28031 Madrid, Spain, Centro Nacional de Biotecnología (CSIC), Darwin, 3, Cantoblanco, 28049 Madrid, Spain
| | - George Perry
- University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249-0667, USA and
| | - Jesús Avila
- Centro de Biología Molecular 'Severo Ochoa' (UAM-CSIC), Nicolás Cabrera, 1. Cantoblanco, 28049 Madrid, Spain, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Valderrebollo, 5, 28031 Madrid, Spain
| | - Vega García-Escudero
- Centro de Biología Molecular 'Severo Ochoa' (UAM-CSIC), Nicolás Cabrera, 1. Cantoblanco, 28049 Madrid, Spain, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Valderrebollo, 5, 28031 Madrid, Spain, Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, UAM, Arzobispo Morcillo, 4, 28029 Madrid, Spain
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48
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Lorenz A, Lorenz M, Vothknecht UC, Niopek-Witz S, Neuhaus HE, Haferkamp I. In vitro analyses of mitochondrial ATP/phosphate carriers from Arabidopsis thaliana revealed unexpected Ca(2+)-effects. BMC PLANT BIOLOGY 2015; 15:238. [PMID: 26444389 PMCID: PMC4595200 DOI: 10.1186/s12870-015-0616-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 09/12/2015] [Indexed: 05/05/2023]
Abstract
BACKGROUND Adenine nucleotide/phosphate carriers (APCs) from mammals and yeast are commonly known to adapt the mitochondrial adenine nucleotide pool in accordance to cellular demands. They catalyze adenine nucleotide--particularly ATP-Mg--and phosphate exchange and their activity is regulated by calcium. Our current knowledge about corresponding proteins from plants is comparably limited. Recently, the three putative APCs from Arabidopsis thaliana were shown to restore the specific growth phenotype of APC yeast loss-of-function mutants and to interact with calcium via their N-terminal EF--hand motifs in vitro. In this study, we performed biochemical characterization of all three APC isoforms from A. thaliana to gain further insights into their functional properties. RESULTS Recombinant plant APCs were functionally reconstituted into liposomes and their biochemical characteristics were determined by transport measurements using radiolabeled substrates. All three plant APCs were capable of ATP, ADP and phosphate exchange, however, high preference for ATP-Mg, as shown for orthologous carriers, was not detectable. By contrast, the obtained data suggest that in the liposomal system the plant APCs rather favor ATP-Ca as substrate. Moreover, investigation of a representative mutant APC protein revealed that the observed calcium effects on ATP transport did not primarily/essentially involve Ca(2+)-binding to the EF-hand motifs in the N-terminal domain of the carrier. CONCLUSION Biochemical characteristics suggest that plant APCs can mediate net transport of adenine nucleotides and hence, like their pendants from animals and yeast, might be involved in the alteration of the mitochondrial adenine nucleotide pool. Although, ATP-Ca was identified as an apparent import substrate of plant APCs in vitro it is arguable whether ATP-Ca formation and thus the corresponding transport can take place in vivo.
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Affiliation(s)
- André Lorenz
- Cellular Physiology/Membrane Transport, University of Kaiserslautern, 67653, Kaiserslautern, Germany.
| | - Melanie Lorenz
- Cellular Physiology/Membrane Transport, University of Kaiserslautern, 67653, Kaiserslautern, Germany.
| | - Ute C Vothknecht
- Department of Biology I, Botany, LMU Munich, Großhaderner Str. 2, D-82152, Planegg-Martinsried, Germany.
| | - Sandra Niopek-Witz
- Plant Physiology, University of Kaiserslautern, 67653, Kaiserslautern, Germany.
| | - H Ekkehard Neuhaus
- Plant Physiology, University of Kaiserslautern, 67653, Kaiserslautern, Germany.
| | - Ilka Haferkamp
- Cellular Physiology/Membrane Transport, University of Kaiserslautern, 67653, Kaiserslautern, Germany.
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49
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Harborne SPD, Ruprecht JJ, Kunji ERS. Calcium-induced conformational changes in the regulatory domain of the human mitochondrial ATP-Mg/Pi carrier. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1847:1245-53. [PMID: 26164100 PMCID: PMC4562336 DOI: 10.1016/j.bbabio.2015.07.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/15/2015] [Accepted: 07/06/2015] [Indexed: 12/21/2022]
Abstract
The mitochondrial ATP-Mg/Pi carrier imports adenine nucleotides from the cytosol into the mitochondrial matrix and exports phosphate. The carrier is regulated by the concentration of cytosolic calcium, altering the size of the adenine nucleotide pool in the mitochondrial matrix in response to energetic demands. The protein consists of three domains; (i) the N-terminal regulatory domain, which is formed of two pairs of fused calcium-binding EF-hands, (ii) the C-terminal mitochondrial carrier domain, which is involved in transport, and (iii) a linker region with an amphipathic α-helix of unknown function. The mechanism by which calcium binding to the regulatory domain modulates substrate transport in the carrier domain has not been resolved. Here, we present two new crystal structures of the regulatory domain of the human isoform 1. Careful analysis by SEC confirmed that although the regulatory domain crystallised as dimers, full-length ATP-Mg/Pi carrier is monomeric. Therefore, the ATP-Mg/Pi carrier must have a different mechanism of calcium regulation than the architecturally related aspartate/glutamate carrier, which is dimeric. The structure showed that an amphipathic α-helix is bound to the regulatory domain in a hydrophobic cleft of EF-hand 3/4. Detailed bioinformatics analyses of different EF-hand states indicate that upon release of calcium, EF-hands close, meaning that the regulatory domain would release the amphipathic α-helix. We propose a mechanism for ATP-Mg/Pi carriers in which the amphipathic α-helix becomes mobile upon release of calcium and could block the transport of substrates across the mitochondrial inner membrane.
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Affiliation(s)
- Steven P D Harborne
- The Medical Research Council, Mitochondrial Biology Unit, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Jonathan J Ruprecht
- The Medical Research Council, Mitochondrial Biology Unit, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Edmund R S Kunji
- The Medical Research Council, Mitochondrial Biology Unit, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK.
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50
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Run C, Yang Q, Liu Z, OuYang B, Chou JJ. Molecular Basis of MgATP Selectivity of the Mitochondrial SCaMC Carrier. Structure 2015; 23:1394-1403. [PMID: 26165595 DOI: 10.1016/j.str.2015.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 05/28/2015] [Accepted: 06/04/2015] [Indexed: 01/21/2023]
Abstract
The mitochondrial matrix is the supplier of cellular ATP. The short Ca(2+)-binding mitochondrial carrier (SCaMC) is one of the two mitochondrial carriers responsible for transporting ATP across the mitochondrial inner membrane. While the ADP/ATP carrier (AAC) accounts for the bulk ADP/ATP recycling in the matrix, the function of SCaMC is important for mitochondrial activities that depend on adenine nucleotides, such as gluconeogenesis and mitochondrial biogenesis. A key difference between SCaMC and AAC is that SCaMC selectively transports MgATP whereas AAC only transports free nucleotides. Here, we use a combination of nuclear magnetic resonance experiments and functional mutagenesis to investigate the structural basis of the MgATP selectivity in SCaMC. Our data revealed an MgATP binding site inside the transporter cavity, while identifying an aspartic acid residue that plays an important role in the higher selectivity for MgATP over free ATP.
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Affiliation(s)
- Changqing Run
- National Center for Protein Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China; State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Qin Yang
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Zhijun Liu
- National Center for Protein Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Bo OuYang
- National Center for Protein Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China; State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China.
| | - James J Chou
- National Center for Protein Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China; State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
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