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Uthayabalan S, Lake T, Stathopulos PB. MRS2 missense variation at Asp216 abrogates inhibitory Mg 2+ binding, potentiating cell migration and apoptosis resistance. Protein Sci 2024; 33:e5108. [PMID: 38989547 PMCID: PMC11237551 DOI: 10.1002/pro.5108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 06/06/2024] [Accepted: 06/24/2024] [Indexed: 07/12/2024]
Abstract
Mitochondrial magnesium (Mg2+) is a crucial modulator of protein stability, enzymatic activity, ATP synthesis, and cell death. Mitochondrial RNA splicing protein 2 (MRS2) is the main Mg2+ channel in the inner mitochondrial membrane that mediates influx into the matrix. Recent cryo-electron microscopy (cryo-EM) human MRS2 structures exhibit minimal conformational changes at high and low Mg2+, yet the regulation of human MRS2 and orthologues by Mg2+ binding to analogous matrix domains has been well established. Further, a missense variation at D216 has been identified associated with malignant melanoma and MRS2 expression and activity is implicated in gastric cancer. Thus, to gain more mechanistic and functional insight into Mg2+ sensing by the human MRS2 matrix domain and the association with proliferative disease, we assessed the structural, biophysical, and functional effects of a D216Q mutant. We show that the D216Q mutation is sufficient to abrogate Mg2+-binding and associated conformational changes including increased α-helicity, stability, and monomerization. Further, we reveal that the MRS2 matrix domains interact with ~μM affinity, which is weakened by up to two orders of magnitude in the presence of Mg2+ for wild-type but unaffected for D216Q. Finally, we demonstrate the importance of Mg2+ sensing by MRS2 to prevent matrix Mg2+ overload as HeLa cells overexpressing MRS2 show enhanced Mg2+ uptake, cell migration, and resistance to apoptosis while MRS2 D216Q robustly potentiates these cancer phenotypes. Collectively, our findings further define the MRS2 matrix domain as a critical Mg2+ sensor that undergoes conformational and assembly changes upon Mg2+ interactions dependent on D216 to temper matrix Mg2+ overload.
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Affiliation(s)
- Sukanthathulse Uthayabalan
- Department of Physiology and Pharmacology, Schulich School of Medicine and DentistryUniversity of Western OntarioLondonOntarioCanada
| | - Taylor Lake
- Department of Physiology and Pharmacology, Schulich School of Medicine and DentistryUniversity of Western OntarioLondonOntarioCanada
| | - Peter B. Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and DentistryUniversity of Western OntarioLondonOntarioCanada
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2
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Touyz RM, de Baaij JHF, Hoenderop JGJ. Magnesium Disorders. N Engl J Med 2024; 390:1998-2009. [PMID: 38838313 DOI: 10.1056/nejmra1510603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Affiliation(s)
- Rhian M Touyz
- From the Research Institute of McGill University Health Centre, Departments of Medicine and Family Medicine, McGill University, Montreal (R.M.T.); and the Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, the Netherlands (J.H.F.B., J.G.J.H.)
| | - Jeroen H F de Baaij
- From the Research Institute of McGill University Health Centre, Departments of Medicine and Family Medicine, McGill University, Montreal (R.M.T.); and the Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, the Netherlands (J.H.F.B., J.G.J.H.)
| | - Joost G J Hoenderop
- From the Research Institute of McGill University Health Centre, Departments of Medicine and Family Medicine, McGill University, Montreal (R.M.T.); and the Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, the Netherlands (J.H.F.B., J.G.J.H.)
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3
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Nies DH, Schleuder G, Galea D, Herzberg M. A flow equilibrium of zinc in cells of Cupriavidus metallidurans. J Bacteriol 2024; 206:e0008024. [PMID: 38661374 PMCID: PMC11112998 DOI: 10.1128/jb.00080-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/03/2024] [Indexed: 04/26/2024] Open
Abstract
The hypothesis was tested that a kinetical flow equilibrium of uptake and efflux reactions is responsible for balancing the cellular zinc content. The experiments were done with the metal-resistant bacterium Cupriavidus metallidurans. In pulse-chase experiments, the cells were loaded with radioactive 65Zn and chased with the 100-fold concentration of non-radioactive zinc chloride. In parallel, the cells were loaded with isotope-enriched stable 67Zn and chased with non-enriched zinc to differentiate between zinc pools in the cell. The experiments demonstrated the existence of a kinetical flow equilibrium, resulting in a constant turnover of cell-bound zinc ions. The absence of the metal-binding cytoplasmic components, polyphosphate and glutathione, metal uptake, and metal efflux systems influenced the flow equilibrium. The experiments also revealed that not all zinc uptake and efflux systems are known in C. metallidurans. Cultivation of the cells under zinc-replete, zinc-, and zinc-magnesium-starvation conditions influenced zinc import and export rates. Here, magnesium starvation had a stronger influence compared to zinc starvation. Other metal cations, especially cobalt, affected the cellular zinc pools and zinc export during the chase reaction. In summary, the experiments with 65Zn and 67Zn demonstrated a constant turnover of cell-bound zinc. This indicated that simultaneously occurring import and export reactions in combination with cytoplasmic metal-binding components resulted in a kinetical flow equilibrium that was responsible for the adjustment of the cellular zinc content. IMPORTANCE Understanding the biochemical action of a single enzyme or transport protein is the pre-requisite to obtain insight into its cellular function but this is only one half of the coin. The other side concerns the question of how central metabolic functions of a cell emerge from the interplay of different proteins and other macromolecules. This paper demonstrates that a flow equilibrium of zinc uptake and efflux reactions is at the core of cellular zinc homeostasis and identifies the most important contributors to this flow equilibrium: the uptake and efflux systems and metal-binding components of the cytoplasm.
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Affiliation(s)
- Dietrich H. Nies
- Martin-Luther-University Halle-Wittenberg, Institute for Biology/Microbiology, Halle (Saale), Germany
| | - Grit Schleuder
- Martin-Luther-University Halle-Wittenberg, Institute for Biology/Microbiology, Halle (Saale), Germany
| | - Diana Galea
- Martin-Luther-University Halle-Wittenberg, Institute for Biology/Microbiology, Halle (Saale), Germany
| | - Martin Herzberg
- Martin-Luther-University Halle-Wittenberg, Institute for Biology/Microbiology, Halle (Saale), Germany
- Department of Analytical Chemistry, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany
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4
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Ponnusamy T, Velusamy P, Shanmughapriya S. Mrs2-mediated mitochondrial magnesium uptake is essential for the regulation of MCU-mediated mitochondrial Ca 2+ uptake and viability. Mitochondrion 2024; 76:101877. [PMID: 38599304 DOI: 10.1016/j.mito.2024.101877] [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: 12/27/2023] [Revised: 03/07/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
Mitochondrial Ca2+ uptake is essential in regulating bioenergetics, cell death, and cytosolic Ca2+ transients. Mitochondrial Calcium Uniporter (MCU) mediates the mitochondrial Ca2+ uptake. Though MCU regulation by MICUs is unequivocally established, there needs to be more knowledge of whether divalent cations regulate MCU. Here, we set out to understand the mitochondrial matrix Mg2+-dependent regulation of MCU activity. We showed that decreased matrix [Mg2+] is associated with increased MCU activity and significantly prompted mitochondrial permeability transition pore opening. Our findings support the critical role of mMg2+ in regulating MCU activity.
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Affiliation(s)
- Thiruvelselvan Ponnusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Prema Velusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Santhanam Shanmughapriya
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA.
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5
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Zeinert R, Zhou F, Franco P, Zöller J, Lessen HJ, Aravind L, Langer JD, Sodt AJ, Storz G, Matthies D. Magnesium Transporter MgtA revealed as a Dimeric P-type ATPase. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.28.582502. [PMID: 38464158 PMCID: PMC10925321 DOI: 10.1101/2024.02.28.582502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Magnesium (Mg2+) uptake systems are present in all domains of life given the vital role of this ion. Bacteria acquire Mg2+ via conserved Mg2+ channels and transporters. The transporters are required for growth when Mg2+ is limiting or during bacterial pathogenesis, but, despite their significance, there are no known structures for these transporters. Here we report the first structure of the Mg2+ transporter MgtA solved by single particle cryo-electron microscopy (cryo-EM). Using mild membrane extraction, we obtained high resolution structures of both a homodimeric form (2.9 Å), the first for a P-type ATPase, and a monomeric form (3.6 Å). Each monomer unit of MgtA displays a structural architecture that is similar to other P-type ATPases with a transmembrane domain and two soluble domains. The dimer interface consists of contacts between residues in adjacent soluble nucleotide binding and phosphotransfer regions of the haloacid dehalogenase (HAD) domain. We suggest oligomerization is a conserved structural feature of the diverse family of P-type ATPase transporters. The ATP binding site and conformational dynamics upon nucleotide binding to MgtA were characterized using a combination of cryo-EM, molecular dynamics simulations, hydrogen-deuterium exchange mass spectrometry, and mutagenesis. Our structure also revealed a Mg2+ ion in the transmembrane segments, which, when combined with sequence conservation and mutagenesis studies, allowed us to propose a model for Mg2+ transport across the lipid bilayer. Finally, our work revealed the N-terminal domain structure and cytoplasmic Mg2+ binding sites, which have implications for related P-type ATPases defective in human disease.
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Affiliation(s)
- Rilee Zeinert
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Fei Zhou
- Unit on Structural Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Pedro Franco
- Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Jonathan Zöller
- Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Henry J. Lessen
- Unit on Membrane Chemical Physics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - L. Aravind
- National Center for Biotechnology Information, National Institutes of Health, Bethesda MD 20892, USA
| | - Julian D. Langer
- Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Alexander J. Sodt
- Unit on Membrane Chemical Physics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Gisela Storz
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Doreen Matthies
- Unit on Structural Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
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6
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Wu Y, Zhu L, Zhang Y, Xu W. Multidimensional Applications and Challenges of Riboswitches in Biosensing and Biotherapy. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2304852. [PMID: 37658499 DOI: 10.1002/smll.202304852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/15/2023] [Indexed: 09/03/2023]
Abstract
Riboswitches have received significant attention over the last two decades for their multiple functionalities and great potential for applications in various fields. This article highlights and reviews the recent advances in biosensing and biotherapy. These fields involve a wide range of applications, such as food safety detection, environmental monitoring, metabolic engineering, live cell imaging, wearable biosensors, antibacterial drug targets, and gene therapy. The discovery, origin, and optimization of riboswitches are summarized to help readers better understand their multidimensional applications. Finally, this review discusses the multidimensional challenges and development of riboswitches in order to further expand their potential for novel applications.
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Affiliation(s)
- Yifan Wu
- Key Laboratory of Precision Nutrition and Food Quality, Beijing Laboratory for Food Quality and Safety, Department of Nutrition and Health, China Agricultural University, Beijing, 100191, China
| | - Longjiao Zhu
- Key Laboratory of Precision Nutrition and Food Quality, Beijing Laboratory for Food Quality and Safety, Department of Nutrition and Health, China Agricultural University, Beijing, 100191, China
| | - Yangzi Zhang
- Key Laboratory of Precision Nutrition and Food Quality, Beijing Laboratory for Food Quality and Safety, Department of Nutrition and Health, China Agricultural University, Beijing, 100191, China
| | - Wentao Xu
- Key Laboratory of Precision Nutrition and Food Quality, Beijing Laboratory for Food Quality and Safety, Department of Nutrition and Health, China Agricultural University, Beijing, 100191, China
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Lai LTF, Balaraman J, Zhou F, Matthies D. Cryo-EM structures of human magnesium channel MRS2 reveal gating and regulatory mechanisms. Nat Commun 2023; 14:7207. [PMID: 37938562 PMCID: PMC10632456 DOI: 10.1038/s41467-023-42599-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/16/2023] [Indexed: 11/09/2023] Open
Abstract
Magnesium ions (Mg2+) play an essential role in cellular physiology. In mitochondria, protein and ATP synthesis and various metabolic pathways are directly regulated by Mg2+. MRS2, a magnesium channel located in the inner mitochondrial membrane, mediates the influx of Mg2+ into the mitochondrial matrix and regulates Mg2+ homeostasis. Knockdown of MRS2 in human cells leads to reduced uptake of Mg2+ into mitochondria and disruption of the mitochondrial metabolism. Despite the importance of MRS2, the Mg2+ translocation and regulation mechanisms of MRS2 are still unclear. Here, using cryo-EM we report the structures of human MRS2 in the presence and absence of Mg2+ at 2.8 Å and 3.3 Å, respectively. From the homo-pentameric structures, we identify R332 and M336 as major gating residues, which are then tested using mutagenesis and two cellular divalent ion uptake assays. A network of hydrogen bonds is found connecting the gating residue R332 to the soluble domain, potentially regulating the gate. Two Mg2+-binding sites are identified in the MRS2 soluble domain, distinct from the two sites previously reported in CorA, a homolog of MRS2 in prokaryotes. Altogether, this study provides the molecular basis for understanding the Mg2+ translocation and regulatory mechanisms of MRS2.
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Affiliation(s)
- Louis Tung Faat Lai
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jayashree Balaraman
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Fei Zhou
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Doreen Matthies
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA.
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8
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Elston R, Mulligan C, Thomas GH. Flipping the switch: dynamic modulation of membrane transporter activity in bacteria. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 37948297 DOI: 10.1099/mic.0.001412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
The controlled entry and expulsion of small molecules across the bacterial cytoplasmic membrane is essential for efficient cell growth and cellular homeostasis. While much is known about the transcriptional regulation of genes encoding transporters, less is understood about how transporter activity is modulated once the protein is functional in the membrane, a potentially more rapid and dynamic level of control. In this review, we bring together literature from the bacterial transport community exemplifying the extensive and diverse mechanisms that have evolved to rapidly modulate transporter function, predominantly by switching activity off. This includes small molecule feedback, inhibition by interaction with small peptides, regulation through binding larger signal transduction proteins and, finally, the emerging area of controlled proteolysis. Many of these examples have been discovered in the context of metal transport, which has to finely balance active accumulation of elements that are essential for growth but can also quickly become toxic if intracellular homeostasis is not tightly controlled. Consistent with this, these transporters appear to be regulated at multiple levels. Finally, we find common regulatory themes, most often through the fusion of additional regulatory domains to transporters, which suggest the potential for even more widespread regulation of transporter activity in biology.
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Affiliation(s)
- Rory Elston
- Department of Biology, University of York, York, UK
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9
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Palmgren M. P-type ATPases: Many more enigmas left to solve. J Biol Chem 2023; 299:105352. [PMID: 37838176 PMCID: PMC10654040 DOI: 10.1016/j.jbc.2023.105352] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/02/2023] [Accepted: 10/05/2023] [Indexed: 10/16/2023] Open
Abstract
P-type ATPases constitute a large ancient super-family of primary active pumps that have diverse substrate specificities ranging from H+ to phospholipids. The significance of these enzymes in biology cannot be overstated. They are structurally related, and their catalytic cycles alternate between high- and low-affinity conformations that are induced by phosphorylation and dephosphorylation of a conserved aspartate residue. In the year 1988, all P-type sequences available by then were analyzed and five major families, P1 to P5, were identified. Since then, a large body of knowledge has accumulated concerning the structure, function, and physiological roles of members of these families, but only one additional family, P6 ATPases, has been identified. However, much is still left to be learned. For each family a few remaining enigmas are presented, with the intention that they will stimulate interest in continued research in the field. The review is by no way comprehensive and merely presents personal views with a focus on evolution.
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Affiliation(s)
- Michael Palmgren
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark.
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10
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Takayanagi H, Bardaud JX, Hirata K, Brenner V, Gloaguen E, Ishiuchi SI, Fujii M. Stepwise hydration of [CH 3COOMg] + studied by cold ion trap infrared spectroscopy: insights into interactions in the magnesium channel selection filters. Phys Chem Chem Phys 2023; 25:23923-23928. [PMID: 37642502 DOI: 10.1039/d3cp00992k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The magnesium channel controls Mg2+ concentration in the cell and plays an indispensable role in biological functions. The crystal structure of the Magnesium Transport E channel suggested that Mg2+ hydrated by 6 water molecules is transported through a selection filter consisting of COO- groups on two Asp residues. This Mg2+ motion implies successive pairing with -OOC-R and dissociation mediated by water molecules. For another divalent ion, however, it is known that RCOO-⋯Ca2+ cannot be separated even with 12 water molecules. From this discrepancy, we probe the structure of Mg2+(CH3COO-)(H2O)4-17 clusters by measuring the infrared spectra and monitoring the vibrational frequencies of COO- with the help of quantum chemistry calculations. The hydration by (H2O)6 is not enough to induce ion separation, and partially-separated or separated pairs are formed from 10 water molecules at least. These results suggest that the ion separation between Mg2+ and carboxylate ions in the selection-filter of the MgtE channel not only results from water molecules in their first hydration shell, but also from additional factors including water molecules and protein groups in the second solvation shell of Mg2+.
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Affiliation(s)
- Hikaru Takayanagi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Jean-Xavier Bardaud
- LIDYL, CEA, CNRS, Université Paris Saclay, CEA Saclay, Bât 522, Gif-sur-Yvette 91191, France.
| | - Keisuke Hirata
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Valérie Brenner
- LIDYL, CEA, CNRS, Université Paris Saclay, CEA Saclay, Bât 522, Gif-sur-Yvette 91191, France.
| | - Eric Gloaguen
- LIDYL, CEA, CNRS, Université Paris Saclay, CEA Saclay, Bât 522, Gif-sur-Yvette 91191, France.
| | - Shun-Ichi Ishiuchi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
- IRFI/IPWR, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan
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11
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Erramilli SK, Dominik PK, Deneka D, Tokarz P, Kim SS, Reddy BG, Skrobek BM, Dalmas O, Perozo E, Kossiakoff AA. Conformation-specific Synthetic Antibodies Discriminate Multiple Functional States of the Ion Channel CorA. J Mol Biol 2023; 435:168192. [PMID: 37394032 PMCID: PMC10529903 DOI: 10.1016/j.jmb.2023.168192] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/20/2023] [Accepted: 06/26/2023] [Indexed: 07/04/2023]
Abstract
CorA, the primary magnesium ion channel in prokaryotes and archaea, is a prototypical homopentameric ion channel that undergoes ion-dependent conformational transitions. CorA adopts five-fold symmetric non-conductive states in the presence of high concentrations of Mg2+, and highly asymmetric flexible states in its complete absence. However, the latter were of insufficient resolution to be thoroughly characterized. In order to gain additional insights into the relationship between asymmetry and channel activation, we exploited phage display selection strategies to generate conformation-specific synthetic antibodies (sABs) against CorA in the absence of Mg2+. Two sABs from these selections, C12 and C18, showed different degrees of Mg2+-sensitivity. Through structural, biochemical, and biophysical characterization, we found the sABs are both conformation-specific but probe different features of the channel under open-like conditions. C18 is highly specific to the Mg2+-depleted state of CorA and through negative-stain electron microscopy (ns-EM), we show sAB binding reflects the asymmetric arrangement of CorA protomers in Mg2+-depleted conditions. We used X-ray crystallography to determine a structure at 2.0 Å resolution of sAB C12 bound to the soluble N-terminal regulatory domain of CorA. The structure shows C12 is a competitive inhibitor of regulatory magnesium binding through its interaction with the divalent cation sensing site. We subsequently exploited this relationship to capture and visualize asymmetric CorA states in different [Mg2+] using ns-EM. We additionally utilized these sABs to provide insights into the energy landscape that governs the ion-dependent conformational transitions of CorA.
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Affiliation(s)
- Satchal K Erramilli
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Pawel K Dominik
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Dawid Deneka
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Piotr Tokarz
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Sangwoo S Kim
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Bharat G Reddy
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Blazej M Skrobek
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA; Intercollegiate Faculty of Biotechnology of University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Olivier Dalmas
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Eduardo Perozo
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA; Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, The University of Chicago, Chicago, IL, USA
| | - Anthony A Kossiakoff
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA; Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL, USA.
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12
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Dukic E, van Maldegem KA, Shaikh KM, Fukuda K, Töpel M, Solymosi K, Hellsten J, Hansen TH, Husted S, Higgins J, Sano S, Ishijima S, Spetea C. Chloroplast magnesium transporters play essential but differential roles in maintaining magnesium homeostasis. FRONTIERS IN PLANT SCIENCE 2023; 14:1221436. [PMID: 37692441 PMCID: PMC10484576 DOI: 10.3389/fpls.2023.1221436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 07/07/2023] [Indexed: 09/12/2023]
Abstract
Magnesium (Mg2+) is essential for photosynthesis in the chloroplasts of land plants and algae. Being the central ion of chlorophyll, cofactor and activator of many photosynthetic enzymes including RuBisCO, magnesium-deficient plants may suffer from leaf chlorosis symptoms and retarded growth. Therefore, the chloroplast Mg2+ concentration is tightly controlled by magnesium transport proteins. Recently, three different transporters from two distinct families have been identified in the chloroplast inner envelope of the model plant Arabidopsis thaliana: MGT10, MGR8, and MGR9. Here, we assess the individual roles of these three proteins in maintaining chloroplast Mg2+ homeostasis and regulating photosynthesis, and if their role is conserved in the model green alga Chlamydomonas reinhardtii. Phylogenetic analysis and heterologous expression revealed that the CorC-like MGR8 and MGR9 transport Mg2+ by a different mechanism than the CorA-like MGT10. MGR8 and MGT10 genes are highest expressed in leaves, indicating a function in chloroplast Mg2+ transport. MGR9 is important for chloroplast function and plant adaptation in conditions of deficiency or excess of Mg2+. Transmission electron microscopy indicated that MGT10 plays a differential role in thylakoid stacking than MGR8 and MGR9. Furthermore, we report that MGR8, MGR9, and MGT10 are involved in building up the pH gradient across the thylakoid membrane and activating photoprotection in conditions of excess light, however the mechanism has not been resolved yet. While there are no chloroplast MGR-like transporters in Chlamydomonas, we show that MRS4 is a homolog of MGT10, that is required for photosynthesis and cell growth. Taken together, our findings reveal that the studied Mg2+ transporters play essential but differential roles in maintaining chloroplast Mg2+ homeostasis.
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Affiliation(s)
- Emilija Dukic
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Kim A. van Maldegem
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Kashif Mohd Shaikh
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Kento Fukuda
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - Mats Töpel
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
- IVL Swedish Environmental Research Institute, Gothenburg, Sweden
| | - Katalin Solymosi
- Department of Plant Anatomy, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Jonna Hellsten
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Thomas Hesselhøj Hansen
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren Husted
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - John Higgins
- Department of Geosciences, Princeton University, Princeton, NJ, United States
| | - Satoshi Sano
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - Sumio Ishijima
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - Cornelia Spetea
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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13
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Lai LTF, Balaraman J, Zhou F, Matthies D. Cryo-EM structures of human magnesium channel MRS2 reveal gating and regulatory mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.22.553867. [PMID: 37662257 PMCID: PMC10473633 DOI: 10.1101/2023.08.22.553867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Magnesium ions (Mg2+) play an essential role in cellular physiology. In mitochondria, protein and ATP synthesis and various metabolic pathways are directly regulated by Mg2+. MRS2, a magnesium channel located in the inner mitochondrial membrane, mediates the influx of Mg2+ into the mitochondrial matrix and regulates Mg2+ homeostasis. Knockdown of MRS2 in human cells leads to reduced uptake of Mg2+ into mitochondria and disruption of the mitochondrial metabolism. Despite the importance of MRS2, the Mg2+ translocation and regulation mechanisms of MRS2 are still unclear. Here, using cryo-EM we determined the structure of human MRS2 in the presence and absence of Mg2+ at 2.8 Å and 3.3 Å, respectively. From the homo-pentameric structures, we identified R332 and M336 as major gating residues, which were then tested using mutagenesis and two cellular divalent ion uptake assays. A network of hydrogen bonds was found connecting the gating residue R332 to the soluble domain, potentially regulating the gate. Two Mg2+-binding sites were identified in the MRS2 soluble domain, distinct from the two sites previously reported in CorA, a homolog of MRS2 in prokaryotes. Altogether, this study provides the molecular basis for understanding the Mg2+ translocation and regulatory mechanisms of MRS2.
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Affiliation(s)
- Louis Tung Faat Lai
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Jayashree Balaraman
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Fei Zhou
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
| | - Doreen Matthies
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda MD 20892, USA
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14
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He Z, Tu YC, Tsai CW, Mount J, Zhang J, Tsai MF, Yuan P. Structure and function of the human mitochondrial MRS2 channel. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.12.553106. [PMID: 37645897 PMCID: PMC10462007 DOI: 10.1101/2023.08.12.553106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The human Mitochondrial RNA Splicing 2 protein (MRS2) has been implicated in Mg2+ transport across mitochondrial inner membranes, thus playing an important role in Mg2+ homeostasis critical for mitochondrial integrity and function. However, the molecular mechanisms underlying its fundamental channel properties such as ion selectivity and regulation remain unclear. Here, we present structural and functional investigation of MRS2. Cryo-electron microscopy structures in various ionic conditions reveal a pentameric channel architecture and the molecular basis of ion permeation and potential regulation mechanisms. Electrophysiological analyses demonstrate that MRS2 is a Ca2+-regulated, non-selective channel permeable to Mg2+, Ca2+, Na+ and K+, which contrasts with its prokaryotic ortholog, CorA, operating as a Mg2+-gated Mg2+ channel. Moreover, a conserved arginine ring within the pore of MRS2 functions to restrict cation movements, likely preventing the channel from collapsing the proton motive force that drives mitochondrial ATP synthesis. Together, our results provide a molecular framework for further understanding MRS2 in mitochondrial function and disease.
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Affiliation(s)
- Zhihui He
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA
- These authors contributed equally to this work
| | - Yung-Chi Tu
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- These authors contributed equally to this work
| | - Chen-Wei Tsai
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jonathan Mount
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jingying Zhang
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ming-Feng Tsai
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Peng Yuan
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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15
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Li M, Li Y, Lu Y, Li J, Lu X, Ren Y, Wen T, Wang Y, Chang S, Zhang X, Yang X, Shen Y. Molecular basis of Mg 2+ permeation through the human mitochondrial Mrs2 channel. Nat Commun 2023; 14:4713. [PMID: 37543649 PMCID: PMC10404273 DOI: 10.1038/s41467-023-40516-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/25/2023] [Indexed: 08/07/2023] Open
Abstract
Mitochondrial RNA splicing 2 (Mrs2), a eukaryotic CorA ortholog, enables Mg2+ to permeate the inner mitochondrial membrane and plays an important role in mitochondrial metabolic function. However, the mechanism by which Mrs2 permeates Mg2+ remains unclear. Here, we report four cryo-electron microscopy (cryo-EM) reconstructions of Homo sapiens Mrs2 (hMrs2) under various conditions. All of these hMrs2 structures form symmetrical pentamers with very similar pentamer and protomer conformations. A special structural feature of Cl--bound R-ring, which consists of five Arg332 residues, was found in the hMrs2 structure. Molecular dynamics simulations and mitochondrial Mg2+ uptake assays show that the R-ring may function as a charge repulsion barrier, and Cl- may function as a ferry to jointly gate Mg2+ permeation in hMrs2. In addition, the membrane potential is likely to be the driving force for Mg2+ permeation. Our results provide insights into the channel assembly and Mg2+ permeation of hMrs2.
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Affiliation(s)
- Ming Li
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Yang Li
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Yue Lu
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Jianhui Li
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Xuhang Lu
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Yue Ren
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Tianlei Wen
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Yaojie Wang
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China
| | - Shenghai Chang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, China
- Center of Cryo Electron Microscopy, Zhejiang University, Hangzhou, 310058, China
| | - Xing Zhang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, China
- Center of Cryo Electron Microscopy, Zhejiang University, Hangzhou, 310058, China
| | - Xue Yang
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China.
| | - Yuequan Shen
- State Key Laboratory of Medicinal Chemical Biology and Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300350, China.
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16
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Ponnusamy T, Velusamy P, Kumar A, Morris D, Zhang X, Ning G, Klinger M, Copper JE, Rajan S, Cheung JY, Natarajaseenivasan K, Mnatsakanyan N, Shanmughapriya S. Mitochondrial Magnesium is the cationic rheostat for MCU-mediated mitochondrial Ca 2+ uptake. RESEARCH SQUARE 2023:rs.3.rs-3088175. [PMID: 37502932 PMCID: PMC10371168 DOI: 10.21203/rs.3.rs-3088175/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Calcium (Ca2+) uptake by mitochondria is essential in regulating bioenergetics, cell death, and cytosolic Ca2+ transients. Mitochondrial Calcium Uniporter (MCU) mediates the mitochondrial Ca2+ uptake. MCU is a heterooligomeric complex with a pore-forming component and accessory proteins required for channel activity. Though MCU regulation by MICUs is unequivocally established, there needs to be more knowledge of whether divalent cations regulate MCU. Here we set out to understand the mitochondrial matrix Mg2+-dependent regulation of MCU activity. We showed Mrs2 as the authentic mammalian mitochondrial Mg2+ channel using the planar lipid bilayer recordings. Using a liver-specific Mrs2 KO mouse model, we showed that decreased matrix [Mg2+] is associated with increased MCU activity and matrix Ca2+ overload. The disruption of Mg2+dependent MCU regulation significantly prompted mitochondrial permeability transition pore opening-mediated cell death during tissue IR injury. Our findings support a critical role for mMg2+ in regulating MCU activity and attenuating mCa2+ overload.
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Affiliation(s)
- Thiruvelselvan Ponnusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Prema Velusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Amrendra Kumar
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Daniel Morris
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Xueqian Zhang
- Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School, Worcester, MA 01655, USA
| | - Gang Ning
- Microscopy Core Facility, Penn State Huck Institutes of the Life Sciences, University Park, PA 16802, USA
| | - Marianne Klinger
- Department of Pathology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Jean E. Copper
- Department of Pathology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Sudarsan Rajan
- Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Joseph Y Cheung
- Department of Renal Medicine, Brigham & Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Nelli Mnatsakanyan
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Santhanam Shanmughapriya
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
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17
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Liu W, Khan S, Tong M, Hu H, Yin L, Huang J. Identification and Expression of the CorA/MRS2/ALR Type Magnesium Transporters in Tomato. PLANTS (BASEL, SWITZERLAND) 2023; 12:2512. [PMID: 37447072 DOI: 10.3390/plants12132512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 06/24/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023]
Abstract
Magnesium (Mg2+) is the most abundant divalent ion in plants, participating in numerous metabolic processes in growth and development. CorA/MRS2/ALR type Mg2+ transporters are essential for maintaining Mg2+ homeostasis in plants. However, the candidate protein and its potential functions in the tomato plant have not been fully understood. In this study, we identified seven MGT genes (SlMRS2) in tomato based on sequence similarity, domain analysis, conserved motif identification, and structure prediction. Two SlMRS2 genes were analyzed in the bacterial strain MM281, and a functional complementary assay demonstrated their high-affinity transport of Mg2+. Quantitative real-time PCR analysis revealed that the expressions of these Mg2+ transporters were down-regulated in leaves under Mg2+ limitation, with a greater impact on lower and middle leaves compared to young leaves. Conversely, under Mg2+ toxicity, several genes were up-regulated in leaves with a circadian rhythm. Our findings indicate that members of the SlMRS2 family function as Mg2+ transporters and lay the groundwork for further analysis of their distinct functions in tomato.
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Affiliation(s)
- Wen Liu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, China
| | - Shahbaz Khan
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, China
| | - Mengying Tong
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, China
| | - Haiyan Hu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, China
| | - Liyan Yin
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, Haikou 570228, China
| | - Jiaquan Huang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, China
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18
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Joshua Ashaolu T, Lee CC, Opeolu Ashaolu J, Pourjafar H, Jafari SM. Metal-binding peptides and their potential to enhance the absorption and bioavailability of minerals. Food Chem 2023; 428:136678. [PMID: 37418874 DOI: 10.1016/j.foodchem.2023.136678] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 06/07/2023] [Accepted: 06/18/2023] [Indexed: 07/09/2023]
Abstract
Minerals including calcium, iron, zinc, magnesium, and copper have several human nutritional functions due to their metabolic activities. Body tissues require sufficient levels of a variety of micronutrients to maintain their health. To achieve these micronutrient needs, dietary consumption must be adequate. Dietary proteins may regulate the biological functions of the body in addition to acting as nutrients. Some peptides encoded in the native protein sequences are primarily responsible for the absorption and bioavailability of minerals in physiological functions. Metal-binding peptides (MBPs) were discovered as potential agents for mineral supplements. Nevertheless, sufficient studies on how MBPs affect the biological functions of minerals are lacking. The hypothesis is that the absorption and bioavailability of minerals are significantly influenced by peptides, and these properties are further enhanced by the configuration and attribute of the metal-peptide complex. In this review, the production of MBPs is discussed using various key parameters such as the protein sources and amino acid residues, enzymatic hydrolysis, purification, sequencing and synthesis and in silico analysis of MBPs. The mechanisms of metal-peptide complexes as functional food ingredients are elucidated, including metal-peptide ratio, precursors and ligands, complexation reaction, absorbability and bioavailability. Finally, the characteristics and application of different metal-peptide complexes are also described.
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Affiliation(s)
- Tolulope Joshua Ashaolu
- Institute for Global Health Innovations, Duy Tan University, Da Nang 550000, Viet Nam; Faculty of Medicine, Duy Tan University, Da Nang 550000, Viet Nam
| | - Chi Ching Lee
- Istanbul Sabahattin Zaim University, Faculty of Engineering and Natural Sciences, Department of Food Engineering, Istanbul, Turkey
| | - Joseph Opeolu Ashaolu
- Department of Public Health, Faculty of Basic Medical Sciences, Redeemers University, PMB 230, Ede, Osun State, Nigeria
| | - Hadi Pourjafar
- Dietary Supplements and Probiotic Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Seid Mahdi Jafari
- Department of Food Materials and Process Design Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
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19
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Aoki K, Yamamoto K, Ohkuma M, Sugita T, Tanaka N, Takashima M. Hyphal Growth in Trichosporon asahii Is Accelerated by the Addition of Magnesium. Microbiol Spectr 2023; 11:e0424222. [PMID: 37102973 PMCID: PMC10269644 DOI: 10.1128/spectrum.04242-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 04/10/2023] [Indexed: 04/28/2023] Open
Abstract
Fungal dimorphism involves two morphologies: a unicellular yeast cell and a multicellular hyphal form. Invasion of hyphae into human cells causes severe opportunistic infections. The transition between yeast and hyphal forms is associated with the virulence of fungi; however, the mechanism is poorly understood. Therefore, we aimed to identify factors that induce hyphal growth of Trichosporon asahii, a dimorphic basidiomycete that causes trichosporonosis. T. asahii showed poor growth and formed small cells containing large lipid droplets and fragmented mitochondria when cultivated for 16 h in a nutrient-deficient liquid medium. However, these phenotypes were suppressed via the addition of yeast nitrogen base. When T. asahii cells were cultivated in the presence of different compounds present in the yeast nitrogen base, we found that magnesium sulfate was a key factor for inducing cell elongation, and its addition dramatically restored hyphal growth in T. asahii. In T. asahii hyphae, vacuoles were enlarged, the size of lipid droplets was decreased, and mitochondria were distributed throughout the cell cytoplasm and adjacent to the cell walls. Additionally, hyphal growth was disrupted due to treatment with an actin inhibitor. The actin inhibitor latrunculin A disrupted the mitochondrial distribution even in hyphal cells. Furthermore, magnesium sulfate treatment accelerated hyphal growth in T. asahii for 72 h when the cells were cultivated in a nutrient-deficient liquid medium. Collectively, our results suggest that an increase in magnesium levels triggers the transition from the yeast to hyphal form in T. asahii. These findings will support studies on the pathogenesis of fungi and aid in developing treatments. IMPORTANCE Understanding the mechanism underlying fungal dimorphism is crucial to discern its invasion into human cells. Invasion is caused by the hyphal form rather than the yeast form; therefore, it is important to understand the mechanism of transition from the yeast to hyphal form. To study the transition mechanism, we utilized Trichosporon asahii, a dimorphic basidiomycete that causes severe trichosporonosis since there are fewer studies on T. asahii than on ascomycetes. This study suggests that an increase in Mg2+, the most abundant mineral in living cells, triggers growth of filamentous hyphae and increases the distribution of mitochondria throughout the cell cytoplasm and adjacent to the cell walls in T. asahii. Understanding the mechanism of hyphal growth triggered by Mg2+ increase will provide a model system to explore fungal pathogenicity in the future.
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Affiliation(s)
- Keita Aoki
- Laboratory of Yeast Systematics, Tokyo NODAI Research Institute, Tokyo University of Agriculture, Setagaya, Tokyo, Japan
| | - Kosuke Yamamoto
- Department of Molecular Microbiology, Faculty of Life Sciences, Tokyo University of Agriculture, Setagaya, Tokyo, Japan
| | - Moriya Ohkuma
- Japan Collection of Microorganisms, RIKEN BioResource Research Center, Tsukuba, Ibaraki, Japan
| | - Takashi Sugita
- Department of Microbiology, Meiji Pharmaceutical University, Kiyose, Tokyo, Japan
| | - Naoto Tanaka
- Department of Molecular Microbiology, Faculty of Life Sciences, Tokyo University of Agriculture, Setagaya, Tokyo, Japan
| | - Masako Takashima
- Laboratory of Yeast Systematics, Tokyo NODAI Research Institute, Tokyo University of Agriculture, Setagaya, Tokyo, Japan
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20
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Erramilli SK, Dominik PK, Deneka D, Tokarz P, Kim SS, Reddy BG, Skrobek BM, Dalmas O, Perozo E, Kossiakoff AA. Conformation-specific synthetic antibodies discriminate multiple functional states of the ion channel CorA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.07.539746. [PMID: 37205530 PMCID: PMC10187328 DOI: 10.1101/2023.05.07.539746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
CorA, the primary magnesium ion channel in prokaryotes and archaea, is a prototypical homopentameric ion channel that undergoes ion-dependent conformational transitions. CorA adopts five-fold symmetric non-conductive states in the presence of high concentrations of Mg 2+ , and highly asymmetric flexible states in its complete absence. However, the latter were of insufficient resolution to be thoroughly characterized. In order to gain additional insights into the relationship between asymmetry and channel activation, we exploited phage display selection strategies to generate conformation-specific synthetic antibodies (sABs) against CorA in the absence of Mg 2+ . Two sABs from these selections, C12 and C18, showed different degrees of Mg 2+ -sensitivity. Through structural, biochemical, and biophysical characterization, we found the sABs are both conformation-specific but probe different features of the channel under open-like conditions. C18 is highly specific to the Mg 2+ -depleted state of CorA and through negative-stain electron microscopy (ns-EM), we show sAB binding reflects the asymmetric arrangement of CorA protomers in Mg 2+ -depleted conditions. We used X-ray crystallography to determine a structure at 2.0 Å resolution of sAB C12 bound to the soluble N-terminal regulatory domain of CorA. The structure shows C12 is a competitive inhibitor of regulatory magnesium binding through its interaction with the divalent cation sensing site. We subsequently exploited this relationship to capture and visualize asymmetric CorA states in different [Mg 2+ ] using ns-EM. We additionally utilized these sABs to provide insights into the energy landscape that governs the ion-dependent conformational transitions of CorA.
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21
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Uthayabalan S, Vishnu N, Madesh M, Stathopulos PB. The human MRS2 magnesium-binding domain is a regulatory feedback switch for channel activity. Life Sci Alliance 2023; 6:e202201742. [PMID: 36754568 PMCID: PMC9909464 DOI: 10.26508/lsa.202201742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 02/10/2023] Open
Abstract
Mitochondrial RNA splicing 2 (MRS2) forms a magnesium (Mg2+) entry protein channel in mitochondria. Whereas MRS2 contains two transmembrane domains constituting a pore on the inner mitochondrial membrane, most of the protein resides within the matrix. Yet, the precise structural and functional role of this obtrusive amino terminal domain (NTD) in human MRS2 is unknown. Here, we show that the MRS2 NTD self-associates into a homodimer, contrasting the pentameric assembly of CorA, an orthologous bacterial channel. Mg2+ and calcium suppress lower and higher order oligomerization of MRS2 NTD, whereas cobalt has no effect on the NTD but disassembles full-length MRS2. Mutating-pinpointed residues-mediating Mg2+ binding to the NTD not only selectively decreases Mg2+-binding affinity ∼sevenfold but also abrogates Mg2+ binding-induced secondary, tertiary, and quaternary structure changes. Disruption of NTD Mg2+ binding strikingly potentiates mitochondrial Mg2+ uptake in WT and Mrs2 knockout cells. Our work exposes a mechanism for human MRS2 autoregulation by negative feedback from the NTD and identifies a novel gain of function mutant with broad applicability to future Mg2+ signaling research.
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Affiliation(s)
- Sukanthathulse Uthayabalan
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Canada
| | - Neelanjan Vishnu
- Center for Mitochondrial Medicine, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Muniswamy Madesh
- Center for Mitochondrial Medicine, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Canada
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22
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Lv X, Huang S, Wang J, Han D, Li J, Guo D, Zhu H. Genome-wide identification of Mg 2+ transporters and functional characteristics of DlMGT1 in Dimocarpus longan. FRONTIERS IN PLANT SCIENCE 2023; 14:1110005. [PMID: 36818860 PMCID: PMC9932547 DOI: 10.3389/fpls.2023.1110005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Longan (Dimocarpus Longan) is one of the most important fruit crops in Southern China. Lack of available Mg in acidic soil conditions is a limitation to further increasing longan yield. Magnesium transporter (MGT/MRS2) mediates the uptake, transport, and redistribution of Mg2+ in higher plants. To understand the role of MGTs family members in longan Mg deficiency. We identified and analyzed the protein characteristics, phylogeny, expression changes, subcellular localization, and transcriptional regulation of DlMGTs members. The results showed that, twelve DlMGTs are localized in the cell membrane, chloroplast, and nucleus. The evolutionary differences in MGTs between herbaceous and woody species in different plants. The DlMGTs promoters contained many cis-acting elements and transcription factor binding sites related to the hormone, environmental, and stress response. Subcellular localization assays showed that DlMGT1 localizes in the cell membrane of Arabidopsis protoplasts. The candidate transcription factor DlGATA16, which may regulate the expression of DlMGT1, was localized in the nucleus of tobacco leaves. Dual luciferase analysis demonstrated that DlGATA16 is a potential factor regulating the transcriptional activity of DlMGT1. In this study, we identified and analyzed DlMGTs on a genome-wide scale and the subcellular localization and interaction of DlMGT1 and DlGATA16, which has important implications for further functional analysis studies of MGTs and the use of MGT for longan genetic improvement.
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Affiliation(s)
- Xinmin Lv
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Key Laboratory of Tropical and Subtropical Fruit Tree Research of Guangdong Province, Guangzhou, China
| | - Shilian Huang
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Key Laboratory of Tropical and Subtropical Fruit Tree Research of Guangdong Province, Guangzhou, China
| | - Jing Wang
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Key Laboratory of Tropical and Subtropical Fruit Tree Research of Guangdong Province, Guangzhou, China
| | - Dongmei Han
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Key Laboratory of Tropical and Subtropical Fruit Tree Research of Guangdong Province, Guangzhou, China
| | - Jianguang Li
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Key Laboratory of Tropical and Subtropical Fruit Tree Research of Guangdong Province, Guangzhou, China
| | - Dongliang Guo
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture, Key Laboratory of Tropical and Subtropical Fruit Tree Research of Guangdong Province, Guangzhou, China
| | - Haifeng Zhu
- Key Laboratory of Crop Harvesting Equipment Technology of Zhejiang Province, Jinhua Polytechnic, Jinhua, China
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23
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Tang RJ, Yang Y, Yan YW, Mao DD, Yuan HM, Wang C, Zhao FG, Luan S. Two transporters mobilize magnesium from vacuolar stores to enable plant acclimation to magnesium deficiency. PLANT PHYSIOLOGY 2022; 190:1307-1320. [PMID: 35809075 PMCID: PMC9516776 DOI: 10.1093/plphys/kiac330] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 06/22/2022] [Indexed: 05/19/2023]
Abstract
Magnesium (Mg) is an essential metal for chlorophyll biosynthesis and other metabolic processes in plant cells. Mg is largely stored in the vacuole of various cell types and remobilized to meet cytoplasmic demand. However, the transport proteins responsible for mobilizing vacuolar Mg2+ remain unknown. Here, we identified two Arabidopsis (Arabidopsis thaliana) Mg2+ transporters (MAGNESIUM TRANSPORTER 1 and 2; MGT1 and MGT2) that facilitate Mg2+ mobilization from the vacuole, especially when external Mg supply is limited. In addition to a high degree of sequence similarity, MGT1 and MGT2 exhibited overlapping expression patterns in Arabidopsis tissues, implying functional redundancy. Indeed, the mgt1 mgt2 double mutant, but not mgt1 and mgt2 single mutants, showed exaggerated growth defects as compared to the wild type under low-Mg conditions, in accord with higher expression levels of Mg-starvation gene markers in the double mutant. However, overall Mg level was also higher in mgt1 mgt2, suggesting a defect in Mg2+ remobilization in response to Mg deficiency. Consistently, MGT1 and MGT2 localized to the tonoplast and rescued the yeast (Saccharomyces cerevisiae) mnr2Δ (manganese resistance 2) mutant strain lacking the vacuolar Mg2+ efflux transporter. In addition, disruption of MGT1 and MGT2 suppressed high-Mg sensitivity of calcineurin B-like 2 and 3 (cbl2 cbl3), a mutant defective in vacuolar Mg2+ sequestration, suggesting that vacuolar Mg2+ influx and efflux processes are antagonistic in a physiological context. We further crossed mgt1 mgt2 with mgt6, which lacks a plasma membrane MGT member involved in Mg2+ uptake, and found that the triple mutant was more sensitive to low-Mg conditions than either mgt1 mgt2 or mgt6. Hence, Mg2+ uptake (via MGT6) and vacuolar remobilization (through MGT1 and MGT2) work synergistically to achieve Mg2+ homeostasis in plants, especially under low-Mg supply in the environment.
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Affiliation(s)
- Ren-Jie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
| | - Yang Yang
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing 210093, China
| | - Yu-Wei Yan
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
- Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Maize Research Institute of Sichuan Agricultural University, Chengdu, Sichuan Province, China
| | - Dan-Dan Mao
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
- College of Life Sciences, Hunan Normal University, Changsha 410081, China
| | - Hong-Mei Yuan
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Chao Wang
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA
| | - Fu-Geng Zhao
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing 210093, China
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24
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Zhu Y, Wang Y, Zhang Y, Pu M, Miao W, Bai M, Bao R, Geng J. Ion selectivity and gating behavior of the CorA-type channel Bpss1228. Front Chem 2022; 10:998075. [PMID: 36171999 PMCID: PMC9511408 DOI: 10.3389/fchem.2022.998075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/25/2022] [Indexed: 11/24/2022] Open
Abstract
Magnesium is an essential element to sustain all forms of life. Total intracellular magnesium content is determined by the balance of magnesium influx and efflux. CorA is a divalent selective channel in the metal ion transport superfamily and is the major Mg2+ uptake pathway in prokaryotes and eukaryotic mitochondria. Previous studies have demonstrated that CorA showed distinct magnesium bound closed conformation and Mg2+-free states. In addition, CorA is regulated by cytoplasmic magnesium ions and its gating mechanism has been investigated by electron paramagnetic resonance technique and molecular dynamic simulations. Here, we report a study of the putative CorA-type channel Bpss1228 from Burkholderia pseudomallei, which has been shown to be significantly associated with pseudomallei infection. We expressed and purified the Bpss1228 in full-length. Subsequently, electrophysiological experiments further investigated the electrical characteristics of Bpss1228 and revealed that it was a strictly cation-selective channel. We also proved that Bpss1228 not only possessed magnesium-mediated regulatory property a remarkable ability to be modulated by magnesium ions. Finally, we observed the three-step gating behavior of Bpss1228 on planar lipid bilayer, and further proposed a synergistic gating mechanism by which CorA family channels control intracellular magnesium homeostasis.
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Affiliation(s)
| | | | | | | | | | | | - Rui Bao
- *Correspondence: Rui Bao, ; Jia Geng,
| | - Jia Geng
- *Correspondence: Rui Bao, ; Jia Geng,
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25
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Jin F, Huang Y, Hattori M. Recent Advances in the Structural Biology of Mg 2+ Channels and Transporters. J Mol Biol 2022; 434:167729. [PMID: 35841930 DOI: 10.1016/j.jmb.2022.167729] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 10/17/2022]
Abstract
Magnesium ions (Mg2+) are the most abundant divalent cations in living organisms and are essential for various physiological processes, including ATP utilization and the catalytic activity of numerous enzymes. Therefore, the homeostatic mechanisms associated with cellular Mg2+ are crucial for both eukaryotic and prokaryotic organisms and are thus strictly controlled by Mg2+ channels and transporters. Technological advances in structural biology, such as the expression screening of membrane proteins, in meso phase crystallization, and recent cryo-EM techniques, have enabled the structure determination of numerous Mg2+ channels and transporters. In this review article, we provide an overview of the families of Mg2+ channels and transporters (MgtE/SLC41, TRPM6/7, CorA/Mrs2, CorC/CNNM), and discuss the structural biology prospects based on the known structures of MgtE, TRPM7, CorA and CorC.
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Affiliation(s)
- Fei Jin
- State Key Laboratory of Genetic Engineering, Shanghai Key Laboratory of Bioactive Small Molecules, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Neurobiology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yichen Huang
- State Key Laboratory of Genetic Engineering, Shanghai Key Laboratory of Bioactive Small Molecules, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Neurobiology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Motoyuki Hattori
- State Key Laboratory of Genetic Engineering, Shanghai Key Laboratory of Bioactive Small Molecules, Collaborative Innovation Center of Genetics and Development, Department of Physiology and Neurobiology, School of Life Sciences, Fudan University, Shanghai 200438, China.
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26
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Franken GAC, Huynen MA, Martínez-Cruz LA, Bindels RJM, de Baaij JHF. Structural and functional comparison of magnesium transporters throughout evolution. Cell Mol Life Sci 2022; 79:418. [PMID: 35819535 PMCID: PMC9276622 DOI: 10.1007/s00018-022-04442-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/22/2022] [Accepted: 06/21/2022] [Indexed: 12/16/2022]
Abstract
Magnesium (Mg2+) is the most prevalent divalent intracellular cation. As co-factor in many enzymatic reactions, Mg2+ is essential for protein synthesis, energy production, and DNA stability. Disturbances in intracellular Mg2+ concentrations, therefore, unequivocally result in delayed cell growth and metabolic defects. To maintain physiological Mg2+ levels, all organisms rely on balanced Mg2+ influx and efflux via Mg2+ channels and transporters. This review compares the structure and the function of prokaryotic Mg2+ transporters and their eukaryotic counterparts. In prokaryotes, cellular Mg2+ homeostasis is orchestrated via the CorA, MgtA/B, MgtE, and CorB/C Mg2+ transporters. For CorA, MgtE, and CorB/C, the motifs that form the selectivity pore are conserved during evolution. These findings suggest that CNNM proteins, the vertebrate orthologues of CorB/C, also have Mg2+ transport capacity. Whereas CorA and CorB/C proteins share the gross quaternary structure and functional properties with their respective orthologues, the MgtE channel only shares the selectivity pore with SLC41 Na+/Mg2+ transporters. In eukaryotes, TRPM6 and TRPM7 Mg2+ channels provide an additional Mg2+ transport mechanism, consisting of a fusion of channel with a kinase. The unique features these TRP channels allow the integration of hormonal, cellular, and transcriptional regulatory pathways that determine their Mg2+ transport capacity. Our review demonstrates that understanding the structure and function of prokaryotic magnesiotropic proteins aids in our basic understanding of Mg2+ transport.
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Affiliation(s)
- G A C Franken
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - M A Huynen
- Center for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - L A Martínez-Cruz
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Bizkaia Science and Technology Park, Derio, 48160, Bizkaia, Spain
| | - R J M Bindels
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - J H F de Baaij
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
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27
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Ge M, Zhong R, Sadeghnezhad E, Hakeem A, Xiao X, Wang P, Fang J. Genome-wide identification and expression analysis of magnesium transporter gene family in grape (Vitis vinifera). BMC PLANT BIOLOGY 2022; 22:217. [PMID: 35477360 PMCID: PMC9047265 DOI: 10.1186/s12870-022-03599-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 04/14/2022] [Indexed: 05/27/2023]
Abstract
BACKGROUND Magnesium ion is one of the essential mineral elements for plant growth and development, which participates in a variety of physiological and biochemical processes. Since there is no report on the research of magnesium ion transporter in grape, the study of the structure and function of magnesium ion transporters (MGT) is helpful to understand the dynamic balance mechanism of intracellular magnesium ions and their inter- or intra-cellular activities. RESULT In this study, we identified the members of MGT protein family in grape and performed the phylogenetic and expression analysis. We have identified nine VvMGT genes in grape genome, which are distributed on eight different chromosomes. Phylogenetic analysis showed that MGT family members of grapes were divided into five subfamilies and had obvious homology with Arabidopsis, maize, and pear. Based on transcriptome data from the web databases, we analyzed the expression patterns of VvMGTs at different development stages and in response to abiotic stresses including waterlogging, drought, salinity, and copper. Using qRT-PCR method, we tested the expression of grape VvMGTs under magnesium and aluminum treatments and found significant changes in VvMGTs expression. In addition, four of the MGT proteins in grape were located in the nucleus. CONCLUSION Overall, in this study we investigated the structural characteristics, evolution pattern, and expression analysis of VvMGTs in depth, which laid the foundation for further revealing the function of VvMGT genes in grape.
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Affiliation(s)
- Mengqing Ge
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Rong Zhong
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ehsan Sadeghnezhad
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Abdul Hakeem
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xin Xiao
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Peipei Wang
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jinggui Fang
- College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
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28
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Ishfaq M, Wang Y, Yan M, Wang Z, Wu L, Li C, Li X. Physiological Essence of Magnesium in Plants and Its Widespread Deficiency in the Farming System of China. FRONTIERS IN PLANT SCIENCE 2022; 13:802274. [PMID: 35548291 PMCID: PMC9085447 DOI: 10.3389/fpls.2022.802274] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/14/2022] [Indexed: 05/14/2023]
Abstract
Magnesium (Mg) is an essential nutrient for a wide array of fundamental physiological and biochemical processes in plants. It largely involves chlorophyll synthesis, production, transportation, and utilization of photoassimilates, enzyme activation, and protein synthesis. As a multifaceted result of the introduction of high-yielding fertilizer-responsive cultivars, intensive cropping without replenishment of Mg, soil acidification, and exchangeable Mg (Ex-Mg) leaching, Mg has become a limiting nutrient for optimum crop production. However, little literature is available to better understand distinct responses of plants to Mg deficiency, the geographical distribution of soil Ex-Mg, and the degree of Mg deficiency. Here, we summarize the current state of knowledge of key plant responses to Mg availability and, as far as possible, highlight spatial Mg distribution and the magnitude of Mg deficiency in different cultivated regions of the world with a special focus on China. In particular, ~55% of arable lands in China are revealed Mg-deficient (< 120 mg kg-1 soil Ex-Mg), and Mg deficiency literally becomes increasingly severe from northern (227-488 mg kg-1) to southern (32-89 mg kg-1) China. Mg deficiency primarily traced back to higher depletion of soil Ex-Mg by fruits, vegetables, sugarcane, tubers, tea, and tobacco cultivated in tropical and subtropical climate zones. Further, each unit decline in soil pH from neutral reduced ~2-fold soil Ex-Mg. This article underscores the physiological importance of Mg, potential risks associated with Mg deficiency, and accordingly, to optimize fertilization strategies for higher crop productivity and better quality.
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Affiliation(s)
- Muhammad Ishfaq
- Key Laboratory of Plant-Soil Interactions, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Ministry of Education, China Agricultural University, Beijing, China
| | - Yongqi Wang
- Key Laboratory of Plant-Soil Interactions, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Ministry of Education, China Agricultural University, Beijing, China
| | - Minwen Yan
- Key Laboratory of Plant-Soil Interactions, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Ministry of Education, China Agricultural University, Beijing, China
| | | | - Liangquan Wu
- International Magnesium Institute, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Chunjian Li
- Key Laboratory of Plant-Soil Interactions, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Ministry of Education, China Agricultural University, Beijing, China
- International Magnesium Institute, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xuexian Li
- Key Laboratory of Plant-Soil Interactions, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Ministry of Education, China Agricultural University, Beijing, China
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29
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Johansen NT, Bonaccorsi M, Bengtsen T, Larsen AH, Tidemand FG, Pedersen MC, Huda P, Berndtsson J, Darwish T, Yepuri NR, Martel A, Pomorski TG, Bertarello A, Sansom MS, Rapp M, Crehuet R, Schubeis T, Lindorff-Larsen K, Pintacuda G, Arleth L. Mg 2+-dependent conformational equilibria in CorA and an integrated view on transport regulation. eLife 2022; 11:71887. [PMID: 35129435 PMCID: PMC8865849 DOI: 10.7554/elife.71887] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 02/04/2022] [Indexed: 11/13/2022] Open
Abstract
The CorA family of proteins regulates the homeostasis of divalent metal ions in many bacteria, archaea, and eukaryotic mitochondria, making it an important target in the investigation of the mechanisms of transport and its functional regulation. Although numerous structures of open and closed channels are now available for the CorA family, the mechanism of the transport regulation remains elusive. Here, we investigated the conformational distribution and associated dynamic behaviour of the pentameric Mg2+ channel CorA at room temperature using small-angle neutron scattering (SANS) in combination with molecular dynamics (MD) simulations and solid-state nuclear magnetic resonance spectroscopy (NMR). We find that neither the Mg2+-bound closed structure nor the Mg2+-free open forms are sufficient to explain the average conformation of CorA. Our data support the presence of conformational equilibria between multiple states, and we further find a variation in the behaviour of the backbone dynamics with and without Mg2+. We propose that CorA must be in a dynamic equilibrium between different non-conducting states, both symmetric and asymmetric, regardless of bound Mg2+ but that conducting states become more populated in Mg2+-free conditions. These properties are regulated by backbone dynamics and are key to understanding the functional regulation of CorA.
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Affiliation(s)
| | - Marta Bonaccorsi
- Centre de RMN à Très hauts Champs de Lyon, UMR 5280, CNRS, University of Lyon, Villeurbanne, France
| | - Tone Bengtsen
- Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Andreas Haahr Larsen
- Condensed Matter Physics, Niels Bohr Institute, University of Copenhagen, Copenhagen E, Denmark
| | | | - Martin Cramer Pedersen
- Condensed Matter Physics, Niels Bohr Institute, University of Copenhagen, Copenhagen E, Denmark
| | - Pie Huda
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane, Australia
| | - Jens Berndtsson
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Tamim Darwish
- National Deuteration Facility, Australian Nuclear Science and Technology Organization, Lucas Heights, Australia
| | - Nageshewar Rao Yepuri
- National Deuteration Facility, Australian Nuclear Science and Technology Organization, Lucas Heights, Australia
| | | | - Thomas Günther Pomorski
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Andrea Bertarello
- Centre de RMN à Très hauts Champs de Lyon, UMR 5280, CNRS, University of Lyon, Villeurbanne, France
| | - Mark Sp Sansom
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Mikaela Rapp
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Ramon Crehuet
- Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Tobias Schubeis
- Centre de RMN à Très hauts Champs de Lyon, UMR 5280, CNRS, University of Lyon, Villeurbanne, France
| | | | - Guido Pintacuda
- Centre de RMN à Très hauts Champs de Lyon, UMR 5280, CNRS, University of Lyon, Villeurbanne, France
| | - Lise Arleth
- Condensed Matter Physics, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
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30
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Tang RJ, Meng SF, Zheng XJ, Zhang B, Yang Y, Wang C, Fu AG, Zhao FG, Lan WZ, Luan S. Conserved mechanism for vacuolar magnesium sequestration in yeast and plant cells. NATURE PLANTS 2022; 8:181-190. [PMID: 35087208 DOI: 10.1038/s41477-021-01087-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Magnesium (Mg2+) is an essential nutrient for all life forms. In fungal and plant cells, the majority of Mg2+ is stored in the vacuole but mechanisms for Mg2+ transport into the vacuolar store are not fully understood. Here we demonstrate that members of ancient conserved domain proteins (ACDPs) from Saccharomyces cerevisiae and Arabidopsis thaliana function in vacuolar Mg2+ sequestration that enables plant and yeast cells to cope with high levels of external Mg2+. We show that the yeast genome (as well as other fungal genomes) harbour a single ACDP homologue, referred to as MAM3, that functions specifically in vacuolar Mg2+ accumulation and is essential for tolerance to high Mg. In parallel, vacuolar ACDP homologues were identified from Arabidopsis and shown to complement the yeast mutant mam3Δ. An Arabidopsis mutant lacking one of the vacuolar ACDP homologues displayed hypersensitivity to high-Mg conditions and accumulated less Mg in the vacuole compared with the wild type. Taken together, our results suggest that conserved transporters mediate vacuolar Mg2+ sequestration in fungal and plant cells to maintain cellular Mg2+ homeostasis in response to fluctuating Mg2+ levels in the environment.
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Affiliation(s)
- Ren-Jie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Su-Fang Meng
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Xiao-Jiang Zheng
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- College of Life Sciences, Northwest University, Xi'an, China
| | - Bin Zhang
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
- College of Life Sciences, Northwest University, Xi'an, China
| | - Yang Yang
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Chao Wang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- College of Life Sciences, Northwest University, Xi'an, China
| | - Ai-Gen Fu
- College of Life Sciences, Northwest University, Xi'an, China
| | - Fu-Geng Zhao
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Wen-Zhi Lan
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China.
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
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31
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Ramanadane K, Straub MS, Dutzler R, Manatschal C. Structural and functional properties of a magnesium transporter of the SLC11/NRAMP family. eLife 2022; 11:74589. [PMID: 35001872 PMCID: PMC8806188 DOI: 10.7554/elife.74589] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
Members of the ubiquitous SLC11/NRAMP family catalyze the uptake of divalent transition metal ions into cells. They have evolved to efficiently select these trace elements from a large pool of Ca2+ and Mg2+, which are both orders of magnitude more abundant, and to concentrate them in the cytoplasm aided by the cotransport of H+ serving as energy source. In the present study, we have characterized a member of a distant clade of the family found in prokaryotes, termed NRMTs, that were proposed to function as transporters of Mg2+. The protein transports Mg2+ and Mn2+ but not Ca2+ by a mechanism that is not coupled to H+. Structures determined by cryo-EM and X-ray crystallography revealed a generally similar protein architecture compared to classical NRAMPs, with a restructured ion binding site whose increased volume provides suitable interactions with ions that likely have retained much of their hydration shell.
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Affiliation(s)
| | - Monique S Straub
- Department of Biochemistry, University of Zurich, Zürich, Switzerland
| | - Raimund Dutzler
- Department of Biochemistry, University of Zurich, Zürich, Switzerland
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32
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Abstract
CNNM/CorB proteins are a broadly conserved family of integral membrane proteins with close to 90,000 protein sequences known. They are associated with Mg2+ transport but it is not known if they mediate transport themselves or regulate other transporters. Here, we determine the crystal structure of an archaeal CorB protein in two conformations (apo and Mg2+-ATP bound). The transmembrane DUF21 domain exists in an inward-facing conformation with a Mg2+ ion coordinated by a conserved π-helix. In the absence of Mg2+-ATP, the CBS-pair domain adopts an elongated dimeric configuration with previously unobserved domain-domain contacts. Hydrogen-deuterium exchange mass spectrometry, analytical ultracentrifugation, and molecular dynamics experiments support a role of the structural rearrangements in mediating Mg2+-ATP sensing. Lastly, we use an in vitro, liposome-based assay to demonstrate direct Mg2+ transport by CorB proteins. These structural and functional insights provide a framework for understanding function of CNNMs in Mg2+ transport and associated diseases.
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33
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Nemchinova M, Melcr J, Wassenaar TA, Marrink SJ, Guskov A. Asymmetric CorA Gating Mechanism as Observed by Molecular Dynamics Simulations. J Chem Inf Model 2021; 61:2407-2417. [PMID: 33886304 PMCID: PMC8154316 DOI: 10.1021/acs.jcim.1c00261] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
The CorA family of
proteins plays a housekeeping role in the homeostasis
of divalent metal ions in many bacteria and archaea as well as in
mitochondria of eukaryotes, rendering it an important target to study
the mechanisms of divalent transport and regulation across different
life domains. Despite numerous studies, the mechanistic details of
the channel gating and the transport of the metal ions are still not
entirely understood. Here, we use all-atom and coarse-grained molecular
dynamics simulations combined with in vitro experiments
to investigate the influence of divalent cations on the function of
CorA. Simulations reveal pronounced asymmetric movements of monomers
that enable the rotation of the α7 helix and the cytoplasmic
subdomain with the subsequent formation of new interactions and the
opening of the channel. These computational results are functionally
validated using site-directed mutagenesis of the intracellular cytoplasmic
domain residues and biochemical assays. The obtained results infer
a complex network of interactions altering the structure of CorA to
allow gating. Furthermore, we attempt to reconcile the existing gating
hypotheses for CorA to conclude the mechanism of transport of divalent
cations via these proteins.
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Affiliation(s)
- Mariia Nemchinova
- Groningen Institute for Biomolecular Sciences and Biotechnology, University of Groningen, 9747AG Groningen, The Netherlands
| | - Josef Melcr
- Groningen Institute for Biomolecular Sciences and Biotechnology, University of Groningen, 9747AG Groningen, The Netherlands
| | - Tsjerk A Wassenaar
- Groningen Institute for Biomolecular Sciences and Biotechnology, University of Groningen, 9747AG Groningen, The Netherlands
| | - Siewert J Marrink
- Groningen Institute for Biomolecular Sciences and Biotechnology, University of Groningen, 9747AG Groningen, The Netherlands
| | - Albert Guskov
- Groningen Institute for Biomolecular Sciences and Biotechnology, University of Groningen, 9747AG Groningen, The Netherlands
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Buetti-Dinh A, Ruinelli M, Czerski D, Scapozza C, Martignier A, Roman S, Caminada A, Tonolla M. Geochemical and metagenomics study of a metal-rich, green-turquoise-coloured stream in the southern Swiss Alps. PLoS One 2021; 16:e0248877. [PMID: 33784327 PMCID: PMC8009434 DOI: 10.1371/journal.pone.0248877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 03/07/2021] [Indexed: 12/02/2022] Open
Abstract
The Swiss Alpine environments are poorly described from a microbiological perspective. Near the Greina plateau in the Camadra valley in Ticino (southern Swiss Alps), a green-turquoise-coloured water spring streams off the mountain cliffs. Geochemical profiling revealed naturally elevated concentrations of heavy metals such as copper, lithium, zinc and cadmium, which are highly unusual for the geomorphology of the region. Of particular interest, was the presence of a thick biofilm, that was revealed by microscopic analysis to be mainly composed of Cyanobacteria. A metagenome was further assembled to detail the genes found in this environment. A multitude of genes for resistance/tolerance to high heavy metal concentrations were indeed found, such as, various transport systems, and genes involved in the synthesis of extracellular polymeric substances (EPS). EPS have been evoked as a central component in photosynthetic environments rich in heavy metals, for their ability to drive the sequestration of toxic, positively-charged metal ions under high regimes of cyanobacteria-driven photosynthesis. The results of this study provide a geochemical and microbiological description of this unusual environment in the southern Swiss Alps, the role of cyanobacterial photosynthesis in metal resistance, and the potential role of such microbial community in bioremediation of metal-contaminated environments.
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Affiliation(s)
- Antoine Buetti-Dinh
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
- * E-mail: (ABD); (MT)
| | - Michela Ruinelli
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
| | - Dorota Czerski
- Institute of Earth Sciences, University of Applied Sciences of Southern Switzerland (SUPSI), Trevano, Canobbio, Switzerland
| | - Cristian Scapozza
- Institute of Earth Sciences, University of Applied Sciences of Southern Switzerland (SUPSI), Trevano, Canobbio, Switzerland
| | - Agathe Martignier
- Department of Earth Sciences, University of Geneva, Geneva, Switzerland
| | - Samuele Roman
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
| | - Annapaola Caminada
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
| | - Mauro Tonolla
- Laboratory of Applied Microbiology (LMA), Department of Environment, Constructions and Design (DACD), University of Applied Sciences of Southern Switzerland (SUPSI), Bellinzona, Switzerland
- Alpine Biology Center Foundation, Bellinzona, Switzerland
- Microbiology Unit, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
- * E-mail: (ABD); (MT)
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Functional analysis of whether the glycine residue of the GMN motif of the Arabidopsis MRS2/MGT/CorA-type Mg 2+ channel protein AtMRS2-11 is critical for Mg 2+ transport activity. Arch Biochem Biophys 2020; 697:108673. [PMID: 33217378 DOI: 10.1016/j.abb.2020.108673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 10/09/2020] [Accepted: 11/08/2020] [Indexed: 11/21/2022]
Abstract
Magnesium (Mg2+) plays a critical role in many physiological processes. The AtMRS2/MGT family, which contains nine Arabidopsis genes (and two pseudogenes), belongs to a eukaryotic subset of the CorA superfamily of divalent cation transporters. AtMRS2-11/MGT10 possesses the signature GlyMetAsn sequence (the GMN motif) conserved in the CorA superfamily; however, little is known about the role of the GMN motif in AtMRS2. Direct measurement using the fluorescent dye mag-fura-2 revealed that reconstituted AtMRS2-11 mediated rapid Mg2+ uptake into proteoliposomes at extraliposomal Mg2+ concentrations of 10 and 20 mM. Mutations in the GMN motif, G417 to A, S or V, did not show a significant change in Mg2+ uptake relative to the wild-type protein. The G417W mutant exhibited a significant increase in Mg2+ uptake. The functional complementation assay in Escherichia coli strain TM2 showed that E. coli cells expressing AtMRS2-11 with mutations in G of the GMN motif did not grow in LB medium without Mg2+ supplementation, while growth was observed in LB medium supplemented with 0.5 mM Mg2+; no difference was observed between the growth of TM2 cells expressing the AtMRS2-11 G417W mutant and that of cells expressing wild-type AtMRS2-11. These results suggested that the Mg2+ transport activity of the AtMRS2-11 GMN-motif mutants was low at low physiological Mg2+ concentrations; thus, the Gly residue is critical for Mg2+ transport, and the Mg2+ transport activity of the GMN-motif mutants was increased at high Mg2+ concentrations.
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Daw CC, Ramachandran K, Enslow BT, Maity S, Bursic B, Novello MJ, Rubannelsonkumar CS, Mashal AH, Ravichandran J, Bakewell TM, Wang W, Li K, Madaris TR, Shannon CE, Norton L, Kandala S, Caplan J, Srikantan S, Stathopulos PB, Reeves WB, Madesh M. Lactate Elicits ER-Mitochondrial Mg 2+ Dynamics to Integrate Cellular Metabolism. Cell 2020; 183:474-489.e17. [PMID: 33035451 PMCID: PMC7572828 DOI: 10.1016/j.cell.2020.08.049] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/15/2020] [Accepted: 08/25/2020] [Indexed: 02/06/2023]
Abstract
Mg2+ is the most abundant divalent cation in metazoans and an essential cofactor for ATP, nucleic acids, and countless metabolic enzymes. To understand how the spatio-temporal dynamics of intracellular Mg2+ (iMg2+) are integrated into cellular signaling, we implemented a comprehensive screen to discover regulators of iMg2+ dynamics. Lactate emerged as an activator of rapid release of Mg2+ from endoplasmic reticulum (ER) stores, which facilitates mitochondrial Mg2+ (mMg2+) uptake in multiple cell types. We demonstrate that this process is remarkably temperature sensitive and mediated through intracellular but not extracellular signals. The ER-mitochondrial Mg2+ dynamics is selectively stimulated by L-lactate. Further, we show that lactate-mediated mMg2+ entry is facilitated by Mrs2, and point mutations in the intermembrane space loop limits mMg2+ uptake. Intriguingly, suppression of mMg2+ surge alleviates inflammation-induced multi-organ failure. Together, these findings reveal that lactate mobilizes iMg2+ and links the mMg2+ transport machinery with major metabolic feedback circuits and mitochondrial bioenergetics.
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Affiliation(s)
- Cassidy C Daw
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Karthik Ramachandran
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Benjamin T Enslow
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Soumya Maity
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Brian Bursic
- Department of Physiology and Pharmacology, Western University, London, ON N6A 5C1, Canada
| | - Matthew J Novello
- Department of Physiology and Pharmacology, Western University, London, ON N6A 5C1, Canada
| | - Cherubina S Rubannelsonkumar
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Ayah H Mashal
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Joel Ravichandran
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Terry M Bakewell
- Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Weiwei Wang
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Kang Li
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Travis R Madaris
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Christopher E Shannon
- Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Luke Norton
- Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Soundarya Kandala
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Jeffrey Caplan
- Department of Biological Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA
| | - Subramanya Srikantan
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Western University, London, ON N6A 5C1, Canada
| | - W Brian Reeves
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Muniswamy Madesh
- Department of Medicine, Center for Precision Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Department of Medicine/Cardiology/Diabetes/Nephrology Divisions, University of Texas Health San Antonio, San Antonio, TX 78229, USA.
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Pohland AC, Schneider D. Mg2+ homeostasis and transport in cyanobacteria - at the crossroads of bacterial and chloroplast Mg2+ import. Biol Chem 2020; 400:1289-1301. [PMID: 30913030 DOI: 10.1515/hsz-2018-0476] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 03/19/2019] [Indexed: 12/29/2022]
Abstract
Magnesium cation (Mg2+) is the most abundant divalent cation in living cells, where it is required for various intracellular functions. In chloroplasts and cyanobacteria, established photosynthetic model systems, Mg2+ is the central ion in chlorophylls, and Mg2+ flux across the thylakoid membrane is required for counterbalancing the light-induced generation of a ΔpH across the thylakoid membrane. Yet, not much is known about Mg2+ homoeostasis, transport and distribution within cyanobacteria. However, Mg2+ transport across membranes has been studied in non-photosynthetic bacteria, and first observations and findings are reported for chloroplasts. Cyanobacterial cytoplasmic membranes appear to contain the well-characterized Mg2+ channels CorA and/or MgtE, which both facilitate transmembrane Mg2+ flux down the electrochemical gradient. Both Mg2+ channels are typical for non-photosynthetic bacteria. Furthermore, Mg2+ transporters of the MgtA/B family are also present in the cytoplasmic membrane to mediate active Mg2+ import into the bacterial cell. While the cytoplasmic membrane of cyanobacteria resembles a 'classical' bacterial membrane, essentially nothing is known about Mg2+ channels and/or transporters in thylakoid membranes of cyanobacteria or chloroplasts. As discussed here, at least one Mg2+ channelling protein must be localized within thylakoid membranes. Thus, either one of the 'typical' bacterial Mg2+ channels has a dual localization in the cytoplasmic plus the thylakoid membrane, or another, yet unidentified channel is present in cyanobacterial thylakoid membranes.
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Affiliation(s)
- Anne-Christin Pohland
- Institut für Pharmazie und Biochemie, Johannes-Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 30, D-55128 Mainz, Germany
| | - Dirk Schneider
- Institut für Pharmazie und Biochemie, Johannes-Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 30, D-55128 Mainz, Germany
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Abstract
CorA proteins belong to 2-TM-GxN family of membrane proteins, and play a major role in Mg2+ transport in prokaryotes and eukaryotic mitochondria. The selection of substrate is believed to occur via the signature motif GxN, however there is no consensus how strict this selection within the family. To answer this question, we employed fluorescence-based transport assays on three different family members, namely CorA from bacterium Thermotoga maritima, CorA from the archeon Methanocaldococcus jannaschii and ZntB from bacterium Escherichia coli, reconstituted into proteoliposomes. Our results show that all three proteins readily transport Mg2+, Co2+, Ni2+ and Zn2+, but not Al3+. Despite the similarity in cation specificity, ZntB differs from the CorA proteins, as in the former transport is stimulated by a proton gradient, but in the latter by the membrane potential, confirming the hypothesis that CorA and ZntB proteins diverged to different transport mechanisms within the same protein scaffold.
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Liu X, Guo LX, Luo LJ, Liu YZ, Peng SA. Identification of the magnesium transport (MGT) family in Poncirus trifoliata and functional characterization of PtrMGT5 in magnesium deficiency stress. PLANT MOLECULAR BIOLOGY 2019; 101:551-560. [PMID: 31621003 DOI: 10.1007/s11103-019-00924-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 10/09/2019] [Indexed: 05/20/2023]
Abstract
At least eight MGT genes were identified in citrus and PtrMGT5 plays important role in maintaining Mg homeostasis in citrus by getting involved in the Mg absorption and transport. Magnesium (Mg) is an essential macronutrient for plant growth and development, and the magnesium transporter (MGT) genes participate in mediate Mg2+ uptake, translocation and sequestration into cellular storage compartments. Although several MGT genes have been characterized in various plant species, a comprehensive analysis of the MGT gene family in citrus is still uncharacterized. In this study, eight PtrMGT genes were identified through genome-wide analyses. Phylogenetic analyses revealed that PtrMGT genes were classified into five distinct subfamilies. A quantitative RT-PCR analysis showed that eight PtrMGT genes were expressed in all of the detected tissues and they mainly expressed in the vegetative organs. Expression analyses revealed the PtrMGT genes responded to various Mg deficiency stresses, including absolute Mg deficiency and antagonistic Mg deficiency which caused by low pH or Al toxicity. PtrMGT5, which localizes to the plasma membrane and was transcriptionally active, was functionally characterized. PtrMGT5 overexpression considerably enhanced absolute Mg deficiency and antagonistic Mg deficiency tolerance in transgenic Arabidopsis plants, which was accompanied by increased fresh weight and Mg content, whereas opposite changes were observed when PtrMGT5 homolog in Valencia Orange callus was knocked down. Taken together, PtrMGT5 plays important role in maintaining Mg homeostasis in citrus by getting involved in the Mg absorption and transport.
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Affiliation(s)
- Xiao Liu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
- School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, People's Republic of China
| | - Ling-Xia Guo
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Li-Juan Luo
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Yong-Zhong Liu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| | - Shu-Ang Peng
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
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Rangl M, Schmandt N, Perozo E, Scheuring S. Real time dynamics of Gating-Related conformational changes in CorA. eLife 2019; 8:47322. [PMID: 31774394 PMCID: PMC6927688 DOI: 10.7554/elife.47322] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 11/26/2019] [Indexed: 01/01/2023] Open
Abstract
CorA, a divalent-selective channel in the metal ion transport superfamily, is the major Mg2+-influx pathway in prokaryotes. CorA structures in closed (Mg2+-bound), and open (Mg2+-free) states, together with functional data showed that Mg2+-influx inhibits further Mg2+-uptake completing a regulatory feedback loop. While the closed state structure is a symmetric pentamer, the open state displayed unexpected asymmetric architectures. Using high-speed atomic force microscopy (HS-AFM), we explored the Mg2+-dependent gating transition of single CorA channels: HS-AFM movies during Mg2+-depletion experiments revealed the channel’s transition from a stable Mg2+-bound state over a highly mobile and dynamic state with fluctuating subunits to asymmetric structures with varying degree of protrusion heights from the membrane. Our data shows that at Mg2+-concentration below Kd, CorA adopts a dynamic (putatively open) state of multiple conformations that imply structural rearrangements through hinge-bending in TM1. We discuss how these structural dynamics define the functional behavior of this ligand-dependent channel.
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Affiliation(s)
- Martina Rangl
- Department of Anesthesiology, Weill Cornell Medical College, New York, United States.,Department of Physiology and Biophysics, Weill Cornell Medical College, New York, United States
| | - Nicolaus Schmandt
- Department of Biochemistry and Molecular Biophysics, The University of Chicago, Chicago, United States
| | - Eduardo Perozo
- Department of Biochemistry and Molecular Biophysics, The University of Chicago, Chicago, United States
| | - Simon Scheuring
- Department of Anesthesiology, Weill Cornell Medical College, New York, United States.,Department of Physiology and Biophysics, Weill Cornell Medical College, New York, United States
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Luchini A, Tidemand FG, Johansen NT, Campana M, Sotres J, Ploug M, Cárdenas M, Arleth L. Peptide Disc Mediated Control of Membrane Protein Orientation in Supported Lipid Bilayers for Surface-Sensitive Investigations. Anal Chem 2019; 92:1081-1088. [DOI: 10.1021/acs.analchem.9b04125] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Alessandra Luchini
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | | | | | - Mario Campana
- ISIS-STFC, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX, United Kingdom
| | - Javier Sotres
- Biofilms Research Center for Biointerfaces and Department of Biomedical Science, Faculty of Health and Society, Malmö University, Per Albin Hanssons Väg 35, 214 32 Malmö, Sweden
| | - Michael Ploug
- Biotech Research and Innovation Center, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen, Denmark
- Finsen Laboratory, Rigshospitalet, Ole Maaløes Vej 5, 2200 Copenhagen, Denmark
| | - Marité Cárdenas
- Biofilms Research Center for Biointerfaces and Department of Biomedical Science, Faculty of Health and Society, Malmö University, Per Albin Hanssons Väg 35, 214 32 Malmö, Sweden
| | - Lise Arleth
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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Live-Cell Imaging of Physiologically Relevant Metal Ions Using Genetically Encoded FRET-Based Probes. Cells 2019; 8:cells8050492. [PMID: 31121936 PMCID: PMC6562680 DOI: 10.3390/cells8050492] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/17/2019] [Accepted: 05/21/2019] [Indexed: 01/02/2023] Open
Abstract
Essential biochemical reactions and processes within living organisms are coupled to subcellular fluctuations of metal ions. Disturbances in cellular metal ion homeostasis are frequently associated with pathological alterations, including neurotoxicity causing neurodegeneration, as well as metabolic disorders or cancer. Considering these important aspects of the cellular metal ion homeostasis in health and disease, measurements of subcellular ion signals are of broad scientific interest. The investigation of the cellular ion homeostasis using classical biochemical methods is quite difficult, often even not feasible or requires large cell numbers. Here, we report of genetically encoded fluorescent probes that enable the visualization of metal ion dynamics within individual living cells and their organelles with high temporal and spatial resolution. Generally, these probes consist of specific ion binding domains fused to fluorescent protein(s), altering their fluorescent properties upon ion binding. This review focuses on the functionality and potential of these genetically encoded fluorescent tools which enable monitoring (sub)cellular concentrations of alkali metals such as K+, alkaline earth metals including Mg2+ and Ca2+, and transition metals including Cu+/Cu2+ and Zn2+. Moreover, we discuss possible approaches for the development and application of novel metal ion biosensors for Fe2+/Fe3+, Mn2+ and Na+.
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Zhang L, Wen A, Wu X, Pan X, Wu N, Chen X, Chen Y, Mao D, Chen L, Luan S. Molecular identification of the magnesium transport gene family in Brassica napus. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 136:204-214. [PMID: 30690277 DOI: 10.1016/j.plaphy.2019.01.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 01/14/2019] [Accepted: 01/14/2019] [Indexed: 05/24/2023]
Abstract
Magnesium (Mg2+) is an essential element for plant growth. Its transport and homeostasis in plants is mainly maintained by the MRS2/MGT of Mg2+ transporters. Little is known about the MRS2/MGT gene family in Brassica napus L. (B. napus), one of the most important oil grains. In our present study, we identified 36 putative MRS2/MGT genes (BnMGTs) from B. napus and investigated their phylogeny, expression pattern and function. These BnMGT genes were sorted into five distinguished groups by the phylogenetic analysis, and they were clearly homologous with the MRS2/MGT genes in Arabidopsis and rice. Complementation assays using the Salmonella typhimurium mutant MM281 demonstrated that the BnMGT genes were capable of mediating Mg2+ uptake and transport, with varied affinities to Mg2+. The expression pattern analysis showed that the expression of BnMGTs were tissue-specific and varied in different tissues. This work provides the molecular basis to discover the function of BnMGT gene family in plant growth and development.
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Affiliation(s)
- Lin Zhang
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Anning Wen
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Xiaoqi Wu
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Xiaoling Pan
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Nan Wu
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Xuan Chen
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Yan Chen
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Dandan Mao
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China.
| | - Liangbi Chen
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China.
| | - Sheng Luan
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China; Department of Plant and Microbial Biology, University of California, Berkeley, 94720, California, USA.
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Zhang L, Peng Y, Li J, Tian X, Chen Z. OsMGT1 Confers Resistance to Magnesium Deficiency By Enhancing the Import of Mg in Rice. Int J Mol Sci 2019; 20:ijms20010207. [PMID: 30626062 PMCID: PMC6337559 DOI: 10.3390/ijms20010207] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/30/2018] [Accepted: 01/03/2019] [Indexed: 02/02/2023] Open
Abstract
Magnesium (Mg) is an essential nutrient element for plant growth and plays an important role in numerous physiological and biochemical processes. Mg deficiency inhibits plant growth and has become a growing problem for crop productions in agriculture. However, the molecular mechanisms for the resistance to Mg deficiency in plants were not well understood. In this study, we identified a Mg transporter gene OsMGT1 that confers resistance to Mg deficiency in rice (Oryza sativa). The expression of OsMGT1 was highly induced by Mg deficiency in shoots. Investigation of tissue expression patterns revealed that OsMGT1 was mainly expressed in the phloem region; however, Mg deficiency remarkably enhanced its expression in xylem parenchyma and mesophyll cells in shoots. Knockout of OsMGT1 resulted in a significant reduction in Mg content and biomass when grown at Mg-limited conditions. Furthermore, the sensitivity to low-Mg in mutants was intensified by excessive calcium supply. In addition, overexpression of OsMGT1 increased Mg content and biomass under low-Mg supply. In conclusion, our results indicate that OsMGT1 plays an important role in rice Mg import and is required for the resistance to Mg deficiency, which can be utilized for molecular breeding of low-Mg tolerant plants.
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Affiliation(s)
- Ludan Zhang
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Yuyang Peng
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Jian Li
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Xinyue Tian
- College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Zhichang Chen
- Root Biology Center, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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Rangubpit W, Kitjaruwankul S, Boonamnaj P, Sompornpisut P, Pandey R. Globular bundles and entangled network of proteins (CorA) by a coarse-grained Monte Carlo simulation. AIMS BIOPHYSICS 2019. [DOI: 10.3934/biophy.2019.2.68] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Ishijima S, Manabe Y, Shinkawa Y, Hotta A, Tokumasu A, Ida M, Sagami I. The homologous Arabidopsis MRS2/MGT/CorA-type Mg2+ channels, AtMRS2-10 and AtMRS2-1 exhibit different aluminum transport activity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:2184-2191. [DOI: 10.1016/j.bbamem.2018.08.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/24/2018] [Accepted: 08/29/2018] [Indexed: 11/30/2022]
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Kowatz T, Maguire ME. Loss of cytosolic Mg 2+ binding sites in the Thermotoga maritima CorA Mg 2+ channel is not sufficient for channel opening. Biochim Biophys Acta Gen Subj 2018; 1863:25-30. [PMID: 30293964 DOI: 10.1016/j.bbagen.2018.09.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 08/29/2018] [Accepted: 09/03/2018] [Indexed: 10/28/2022]
Abstract
The CorA Mg2+ channel is a homopentamer with five-fold symmetry. Each monomer consists of a large cytoplasmic domain and two transmembrane helices connected via a short periplasmic loop. In the Thermotoga maritima CorA crystal structure, a Mg2+ is bound between D89 of one monomer and D253 of the adjacent monomer (M1 binding site). Release of Mg2+ from these sites has been hypothesized to cause opening of the channel. We generated mutants to disrupt Mg2+ interaction with the M1 site. Crystal structures of the D89K/D253K and D89R/D253R mutants, determined to 3.05 and 3.3 Å, respectively, showed no significant structural differences with the wild type structure despite absence of Mg2+ at the M1 sites. Both mutants still appear to be in the closed state. All three mutant CorA proteins exhibited transport of 63Ni2+, indicating functionality. Thus, absence of Mg2+ from the M1 sites neither causes channel opening nor prevents function. We also provide evidence that the T. maritima CorA is a Mg2+ channel and not a Co2+ channel.
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Affiliation(s)
- Thomas Kowatz
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4965, USA
| | - Michael E Maguire
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4965, USA.
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Thonghin N, Kargas V, Clews J, Ford RC. Cryo-electron microscopy of membrane proteins. Methods 2018; 147:176-186. [DOI: 10.1016/j.ymeth.2018.04.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/17/2018] [Accepted: 04/20/2018] [Indexed: 10/17/2022] Open
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Cao Y, Dong Y, Chou JJ. Structural and Functional Properties of Viral Membrane Proteins. ADVANCES IN MEMBRANE PROTEINS 2018. [PMCID: PMC7122571 DOI: 10.1007/978-981-13-0532-0_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Viruses have developed a large variety of transmembrane proteins to carry out their infectious cycles. Some of these proteins are simply anchored to membrane via transmembrane helices. Others, however, adopt more interesting structures to perform tasks such as mediating membrane fusion and forming ion-permeating channels. Due to the dynamic or plastic nature shown by many of the viral membrane proteins, structural and mechanistic understanding of these proteins has lagged behind their counterparts in prokaryotes and eukaryotes. This chapter provides an overview of the use of NMR spectroscopy to unveil the transmembrane and membrane-proximal regions of viral membrane proteins, as well as their interactions with potential therapeutics.
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Affiliation(s)
- Yu Cao
- Institute of Precision Medicine, The Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Ren C, Zeng F, Shen J, Chen F, Roy A, Zhou S, Ren H, Zeng H. Pore-Forming Monopeptides as Exceptionally Active Anion Channels. J Am Chem Soc 2018; 140:8817-8826. [DOI: 10.1021/jacs.8b04657] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Changliang Ren
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos 138669, Singapore
| | - Fei Zeng
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos 138669, Singapore
| | - Jie Shen
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos 138669, Singapore
| | - Feng Chen
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos 138669, Singapore
| | - Arundhati Roy
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos 138669, Singapore
| | - Shaoyuan Zhou
- College of Chemical Engineering, Sichuan University, Chengdu 610065, China
| | - Haisheng Ren
- College of Chemical Engineering, Sichuan University, Chengdu 610065, China
| | - Huaqiang Zeng
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos 138669, Singapore
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