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Contreras RG, Torres-Carrillo A, Flores-Maldonado C, Shoshani L, Ponce A. Na +/K +-ATPase: More than an Electrogenic Pump. Int J Mol Sci 2024; 25:6122. [PMID: 38892309 PMCID: PMC11172918 DOI: 10.3390/ijms25116122] [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: 03/26/2024] [Revised: 05/20/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
The sodium pump, or Na+/K+-ATPase (NKA), is an essential enzyme found in the plasma membrane of all animal cells. Its primary role is to transport sodium (Na+) and potassium (K+) ions across the cell membrane, using energy from ATP hydrolysis. This transport creates and maintains an electrochemical gradient, which is crucial for various cellular processes, including cell volume regulation, electrical excitability, and secondary active transport. Although the role of NKA as a pump was discovered and demonstrated several decades ago, it remains the subject of intense research. Current studies aim to delve deeper into several aspects of this molecular entity, such as describing its structure and mode of operation in atomic detail, understanding its molecular and functional diversity, and examining the consequences of its malfunction due to structural alterations. Additionally, researchers are investigating the effects of various substances that amplify or decrease its pumping activity. Beyond its role as a pump, growing evidence indicates that in various cell types, NKA also functions as a receptor for cardiac glycosides like ouabain. This receptor activity triggers the activation of various signaling pathways, producing significant morphological and physiological effects. In this report, we present the results of a comprehensive review of the most outstanding studies of the past five years. We highlight the progress made regarding this new concept of NKA and the various cardiac glycosides that influence it. Furthermore, we emphasize NKA's role in epithelial physiology, particularly its function as a receptor for cardiac glycosides that trigger intracellular signals regulating cell-cell contacts, proliferation, differentiation, and adhesion. We also analyze the role of NKA β-subunits as cell adhesion molecules in glia and epithelial cells.
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Affiliation(s)
| | | | | | | | - Arturo Ponce
- Department of Physiology, Biophysics and Neurosciences, CINVESTAV-IPN, Mexico City 07360, Mexico; (R.G.C.); (A.T.-C.); (C.F.-M.); (L.S.)
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2
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Vishnu N, Venkatesan M, Madaris TR, Venkateswaran MK, Stanley K, Ramachandran K, Chidambaram A, Madesh AK, Yang W, Nair J, Narkunan M, Muthukumar T, Karanam V, Joseph LC, Le A, Osidele A, Aslam MI, Morrow JP, Malicdan MC, Stathopulos PB, Madesh M. ERMA (TMEM94) is a P-type ATPase transporter for Mg 2+ uptake in the endoplasmic reticulum. Mol Cell 2024; 84:1321-1337.e11. [PMID: 38513662 PMCID: PMC10997467 DOI: 10.1016/j.molcel.2024.02.033] [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: 04/22/2023] [Revised: 10/16/2023] [Accepted: 02/27/2024] [Indexed: 03/23/2024]
Abstract
Intracellular Mg2+ (iMg2+) is bound with phosphometabolites, nucleic acids, and proteins in eukaryotes. Little is known about the intracellular compartmentalization and molecular details of Mg2+ transport into/from cellular organelles such as the endoplasmic reticulum (ER). We found that the ER is a major iMg2+ compartment refilled by a largely uncharacterized ER-localized protein, TMEM94. Conventional and AlphaFold2 predictions suggest that ERMA (TMEM94) is a multi-pass transmembrane protein with large cytosolic headpiece actuator, nucleotide, and phosphorylation domains, analogous to P-type ATPases. However, ERMA uniquely combines a P-type ATPase domain and a GMN motif for ERMg2+ uptake. Experiments reveal that a tyrosine residue is crucial for Mg2+ binding and activity in a mechanism conserved in both prokaryotic (mgtB and mgtA) and eukaryotic Mg2+ ATPases. Cardiac dysfunction by haploinsufficiency, abnormal Ca2+ cycling in mouse Erma+/- cardiomyocytes, and ERMA mRNA silencing in human iPSC-cardiomyocytes collectively define ERMA as an essential component of ERMg2+ uptake in eukaryotes.
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Affiliation(s)
- Neelanjan Vishnu
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Manigandan Venkatesan
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Travis R Madaris
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Mridula K Venkateswaran
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Kristen Stanley
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Karthik Ramachandran
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Adhishree Chidambaram
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Abitha K Madesh
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Wenli Yang
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jyotsna Nair
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Melanie Narkunan
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Tharani Muthukumar
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Varsha Karanam
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Leroy C Joseph
- Department of Medicine, College of Physicians and Surgeons of Columbia University, 650 W 168 Street, New York, NY 10032, USA
| | - Amy Le
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Ayodeji Osidele
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - M Imran Aslam
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - John P Morrow
- Department of Medicine, College of Physicians and Surgeons of Columbia University, 650 W 168 Street, New York, NY 10032, USA
| | - May C Malicdan
- Section of Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; NIH Undiagnosed Diseases Program, Office of the Clinical Director, National Human Genome Research Institute, and the Common Fund, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Western University, London, ON N6A 5C1, Canada
| | - Muniswamy Madesh
- Department of Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA; Center for Mitochondrial Medicine, University of Texas Health San Antonio, San Antonio, TX 78229, USA.
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3
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Pietrobon D, Conti F. Astrocytic Na +, K + ATPases in physiology and pathophysiology. Cell Calcium 2024; 118:102851. [PMID: 38308916 DOI: 10.1016/j.ceca.2024.102851] [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: 12/13/2023] [Revised: 01/26/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
The Na+, K+ ATPases play a fundamental role in the homeostatic functions of astrocytes. After a brief historic prologue and discussion of the subunit composition and localization of the astrocytic Na+, K+ ATPases, the review focuses on the role of the astrocytic Na+, K+ pumps in extracellular K+ and glutamate homeostasis, intracellular Na+ and Ca2+ homeostasis and signaling, regulation of synaptic transmission and neurometabolic coupling between astrocytes and neurons. Loss-of-function mutations in the gene encoding the astrocytic α2 Na+, K+ ATPase cause a rare monogenic form of migraine with aura (familial hemiplegic migraine type 2). On the other hand, the α2 Na+, K+ ATPase is upregulated in spinal cord and brain samples from amyotrophic lateral sclerosis and Alzheimer disease patients, respectively. In the last part, the review focuses on i) the migraine relevant phenotypes shown by familial hemiplegic migraine type 2 knock-in mice with 50 % reduced expression of the astrocytic α2 Na+, K+ ATPase and the insights into the pathophysiology of migraine obtained from these genetic mouse models, and ii) the evidence that upregulation of the astrocytic α2 Na+, K+ ATPase in mouse models of amyotrophic lateral sclerosis and Alzheimer disease promotes neuroinflammation and contributes to progressive neurodegeneration.
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Affiliation(s)
- Daniela Pietrobon
- Department of Biomedical Sciences and Padova Neuroscience Center (PNC), University of Padova, Padova 35131, Italy.
| | - Fiorenzo Conti
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
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4
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Clarke RJ. Electrostatic switch mechanisms of membrane protein trafficking and regulation. Biophys Rev 2023; 15:1967-1985. [PMID: 38192346 PMCID: PMC10771482 DOI: 10.1007/s12551-023-01166-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 11/17/2023] [Indexed: 01/10/2024] Open
Abstract
Lipid-protein interactions are normally classified as either specific or general. Specific interactions refer to lipid binding to specific binding sites within a membrane protein, thereby modulating the protein's thermal stability or kinetics. General interactions refer to indirect effects whereby lipids affect membrane proteins by modulating the membrane's physical properties, e.g., its fluidity, thickness, or dipole potential. It is not widely recognized that there is a third distinct type of lipid-protein interaction. Intrinsically disordered N- or C-termini of membrane proteins can interact directly but nonspecifically with the surrounding membrane. Many peripheral membrane proteins are held to the cytoplasmic surface of the plasma membrane via a cooperative combination of two forces: hydrophobic anchoring and electrostatic attraction. An acyl chain, e.g., myristoyl, added post-translationally to one of the protein's termini inserts itself into the lipid matrix and helps hold peripheral membrane proteins onto the membrane. Electrostatic attraction occurs between positively charged basic amino acid residues (lysine and arginine) on one of the protein's terminal tails and negatively charged phospholipid head groups, such as phosphatidylserine. Phosphorylation of either serine or tyrosine residues on the terminal tails via regulatory protein kinases allows for an electrostatic switch mechanism to control trafficking of the protein. Kinase action reduces the positive charge on the protein's tail, weakening the electrostatic attraction and releasing the protein from the membrane. A similar mechanism regulates many integral membrane proteins, but here only electrostatic interactions are involved, and the electrostatic switch modulates protein activity by altering the stabilities of different protein conformational states.
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Affiliation(s)
- Ronald J. Clarke
- School of Chemistry, University of Sydney, Sydney, NSW 2006 Australia
- The University of Sydney Nano Institute, Sydney, NSW 2006 Australia
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5
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Tian Y, Wan N, Zhang H, Shao C, Ding M, Bao Q, Hu H, Sun H, Liu C, Zhou K, Chen S, Wang G, Ye H, Hao H. Chemoproteomic mapping of the glycolytic targetome in cancer cells. Nat Chem Biol 2023; 19:1480-1491. [PMID: 37322158 DOI: 10.1038/s41589-023-01355-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 05/04/2023] [Indexed: 06/17/2023]
Abstract
Hyperactivated glycolysis is a metabolic hallmark of most cancer cells. Although sporadic information has revealed that glycolytic metabolites possess nonmetabolic functions as signaling molecules, how these metabolites interact with and functionally regulate their binding targets remains largely elusive. Here, we introduce a target-responsive accessibility profiling (TRAP) approach that measures changes in ligand binding-induced accessibility for target identification by globally labeling reactive proteinaceous lysines. With TRAP, we mapped 913 responsive target candidates and 2,487 interactions for 10 major glycolytic metabolites in a model cancer cell line. The wide targetome depicted by TRAP unveils diverse regulatory modalities of glycolytic metabolites, and these modalities involve direct perturbation of enzymes in carbohydrate metabolism, intervention of an orphan transcriptional protein's activity and modulation of targetome-level acetylation. These results further our knowledge of how glycolysis orchestrates signaling pathways in cancer cells to support their survival, and inspire exploitation of the glycolytic targetome for cancer therapy.
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Affiliation(s)
- Yang Tian
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Ning Wan
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Hanqing Zhang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Chang Shao
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Ming Ding
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Qiuyu Bao
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Haiyang Hu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Huiyong Sun
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Chenguang Liu
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Kun Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Cardiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Model Animal Research Center, Nanjing University, Nanjing, China
| | - Shuai Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Cardiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Model Animal Research Center, Nanjing University, Nanjing, China
| | - Guangji Wang
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Hui Ye
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China.
| | - Haiping Hao
- Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China.
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6
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Rivera-Morán MA, Sampedro JG. Isolation of the Sarcoplasmic Reticulum Ca 2+-ATPase from Rabbit Fast-Twitch Muscle. Methods Protoc 2023; 6:102. [PMID: 37888034 PMCID: PMC10608927 DOI: 10.3390/mps6050102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/13/2023] [Accepted: 10/17/2023] [Indexed: 10/28/2023] Open
Abstract
The sarcoendoplasmic reticulum Ca2+-ATPase (SERCA) is a membrane protein that is destabilized during purification in the absence of calcium ions. The disaccharide trehalose is a protein stabilizer that accumulates in the yeast cytoplasm when under stress. In the present work, SERCA was purified by including trehalose in the purification protocol. The purified SERCA showed high protein purity (~95%) and ATPase activity. ATP hydrolysis was dependent on the presence of Ca2+ and the enzyme kinetics showed a hyperbolic dependence on ATP (Km = 12.16 ± 2.25 μM ATP). FITC labeling showed the integrity of the ATP-binding site and the identity of the isolated enzyme as a P-type ATPase. Circular dichroism (CD) spectral changes at a wavelength of 225 nm were observed upon titration with ATP, indicating α-helical rearrangements in the nucleotide-binding domain (N-domain), which correlated with ATP affinity (Km). The presence of Ca2+ did not affect FITC labeling or the ATP-mediated structural changes at the N-domain. The use of trehalose in the SERCA purification protocol stabilized the enzyme. The isolated SERCA appears to be suitable for structural and ligand binding studies, e.g., for testing newly designed or natural inhibitors. The use of trehalose is recommended for the isolation of unstable enzymes.
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Affiliation(s)
| | - José G. Sampedro
- Instituto de Física, Universidad Autónoma de San Luis Potosí, Avenida Chapultepec 1570, Privadas del Pedregal, San Luis Potosí 78295, Mexico
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7
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Lev B, Chennath M, Cranfield CG, Cornelius F, Allen TW, Clarke RJ. Involvement of the alpha-subunit N-terminus in the mechanism of the Na +,K +-ATPase. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119539. [PMID: 37479188 DOI: 10.1016/j.bbamcr.2023.119539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/26/2023] [Accepted: 07/10/2023] [Indexed: 07/23/2023]
Abstract
Previous studies have shown that cytoplasmic K+ release and the associated E2 → E1 conformational change of the Na+,K+-ATPase is a major rate-determining step of the enzyme's ion pumping cycle and hence a prime site of acute regulatory intervention. From the ionic strength dependence of the enzyme's distribution between the E2 and E1 states, it has also been found that E2 is stabilized by an electrostatic attraction. Any disruption of this electrostatic attraction would, thus, have profound effects on the rate of ion pumping. The aim of this paper is to identify the location of this interaction. Using enhanced-sampling molecular dynamics simulations with a predicted N-terminal structure added to the X-ray crystal structure of the Na+,K+-ATPase, a previously postulated salt bridge between Lys32 and Glu233 (rat sequence numbering) of the enzyme's α-subunit can be excluded. The residues never approach closely enough to form a salt bridge. In contrast, strong interactions with anionic lipid head groups were seen. To investigate the possibility of a protein-lipid interaction experimentally, the surface charge density of Na+,K+-ATPase-containing membrane fragments was estimated from zeta potential measurements to be 0.019 (± 0.001) C m-2. This is in good agreement with the charge density previously determined to be responsible for stabilization of the E2 state of 0.023 (± 0.009) C m-2 and the membrane charge density estimated here from published electron-microscopic images of 0.018C m-2. The results are, therefore, consistent with an interaction of the Na+,K+-ATPase α-subunit N-terminus with negatively-charged lipid head groups of the neighbouring cytoplasmic membrane surface as the origin of the electrostatic interaction stabilising the E2 state.
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Affiliation(s)
- B Lev
- School of Science, RMIT University, Melbourne, Vic, 3001, Australia
| | - M Chennath
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - C G Cranfield
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - F Cornelius
- Department of Biomedicine, University of Aarhus, DK-8000 Aarhus, C, Denmark
| | - T W Allen
- School of Science, RMIT University, Melbourne, Vic, 3001, Australia
| | - R J Clarke
- School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, Sydney, NSW 2006, Australia.
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8
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Wu M, Wu C, Song T, Pan K, Wang Y, Liu Z. Structure and transport mechanism of the human calcium pump SPCA1. Cell Res 2023; 33:533-545. [PMID: 37258749 PMCID: PMC10313705 DOI: 10.1038/s41422-023-00827-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/08/2023] [Indexed: 06/02/2023] Open
Abstract
Secretory-pathway Ca2+-ATPases (SPCAs) play critical roles in maintaining Ca2+ homeostasis, but the exact mechanism of SPCAs-mediated Ca2+ transport remains unclear. Here, we determined six cryo-electron microscopy (cryo-EM) structures of human SPCA1 (hSPCA1) in a series of intermediate states, revealing a near-complete conformational cycle. With the aid of molecular dynamics simulations, these structures offer a clear structural basis for Ca2+ entry and release in hSPCA1. We found that hSPCA1 undergoes unique conformational changes during ATP binding and phosphorylation compared to other well-studied P-type II ATPases. In addition, we observed a conformational distortion of the Ca2+-binding site induced by the separation of transmembrane helices 4L and 6, unveiling a distinct Ca2+ release mechanism. Particularly, we determined a structure of the long-sought CaE2P state of P-type IIA ATPases, providing valuable insights into the Ca2+ transport cycle. Together, these findings enhance our understanding of Ca2+ transport by hSPCA1 and broaden our knowledge of P-type ATPases.
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Affiliation(s)
- Mengqi Wu
- Department of Immunology and Microbiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Cang Wu
- Department of Immunology and Microbiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Tiefeng Song
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Kewu Pan
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Yong Wang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
- The Provincial International Science and Technology Cooperation Base on Engineering Biology, International Campus of Zhejiang University, Haining, Zhejiang, China.
| | - Zhongmin Liu
- Department of Immunology and Microbiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, China.
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Gillman C, Patel K, Unge J, Gonen T. The structure of the neurotoxin palytoxin determined by MicroED. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.31.535166. [PMID: 37034718 PMCID: PMC10081313 DOI: 10.1101/2023.03.31.535166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Palytoxin (PTX) is a potent neurotoxin found in marine animals that can cause serious symptoms such as muscle contractions, haemolysis of red blood cells and potassium leakage. Despite years of research, very little is known about the mechanism of PTX. However, recent advances in the field of cryoEM, specifically the use of microcrystal electron diffraction (MicroED), have allowed us to determine the structure of PTX. It was discovered that PTX folds into a hairpin motif and is able to bind to the extracellular gate of Na,K-ATPase, which is responsible for maintaining the electrochemical gradient across the plasma membrane. These findings, along with molecular docking simulations, have provided important insights into the mechanism of PTX and can potentially aid in the development of molecular agents for treating cases of PTX exposure.
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Affiliation(s)
- Cody Gillman
- Department of Biological Chemistry, University of California, Los Angeles CA, USA
- Molecular Biology Institute, University of California, Los Angeles CA, USA
| | - Khushboo Patel
- Department of Biological Chemistry, University of California, Los Angeles CA, USA
| | - Johan Unge
- Department of Biological Chemistry, University of California, Los Angeles CA, USA
| | - Tamir Gonen
- Department of Biological Chemistry, University of California, Los Angeles CA, USA
- Molecular Biology Institute, University of California, Los Angeles CA, USA
- Department of Physiology, University of California, Los Angeles CA, USA
- Howard Hughes Medical Institute, University of California, Los Angeles CA, USA
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10
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Zhang YY, Li XS, Ren KD, Peng J, Luo XJ. Restoration of metal homeostasis: a potential strategy against neurodegenerative diseases. Ageing Res Rev 2023; 87:101931. [PMID: 37031723 DOI: 10.1016/j.arr.2023.101931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/11/2023]
Abstract
Metal homeostasis is critical to normal neurophysiological activity. Metal ions are involved in the development, metabolism, redox and neurotransmitter transmission of the central nervous system (CNS). Thus, disturbance of homeostasis (such as metal deficiency or excess) can result in serious consequences, including neurooxidative stress, excitotoxicity, neuroinflammation, and nerve cell death. The uptake, transport and metabolism of metal ions are highly regulated by ion channels. There is growing evidence that metal ion disorders and/or the dysfunction of ion channels contribute to the progression of neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS). Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for diverse neurological diseases. This review summarizes recent advances in the studies regarding the physiological and pathophysiological functions of metal ions and their channels, as well as their role in neurodegenerative diseases. In addition, currently available metal ion modulators and in vivo quantitative metal ion imaging methods are also discussed. Current work provides certain recommendations based on literatures and in-depth reflections to improve neurodegenerative diseases. Future studies should turn to crosstalk and interactions between different metal ions and their channels. Concomitant pharmacological interventions for two or more metal signaling pathways may offer clinical advantages in treating the neurodegenerative diseases.
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Affiliation(s)
- Yi-Yue Zhang
- Department of Pharmacology, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Xi-Sheng Li
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha 410013,China
| | - Kai-Di Ren
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Jun Peng
- Department of Pharmacology, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410078, China.
| | - Xiu-Ju Luo
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha 410013,China.
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