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Kumari K, Dey J, Mahapatra SR, Ma Y, Sharma PK, Misra N, Singh RP. Protein profiling and immunoinformatic analysis of the secretome of a metal-resistant environmental isolate Pseudomonas aeruginosa S-8. Folia Microbiol (Praha) 2024:10.1007/s12223-024-01152-5. [PMID: 38457114 DOI: 10.1007/s12223-024-01152-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 02/03/2024] [Indexed: 03/09/2024]
Abstract
The bacterial secretome represents a comprehensive catalog of proteins released extracellularly that have multiple important roles in virulence and intercellular communication. This study aimed to characterize the secretome of an environmental isolate Pseudomonas aeruginosa S-8 by analyzing trypsin-digested culture supernatant proteins using nano-LC-MS/MS tool. Using a combined approach of bioinformatics and mass spectrometry, 1088 proteins in the secretome were analyzed by PREDLIPO, SecretomeP 2.0, SignalP 4.1, and PSORTb tool for their subcellular localization and further categorization of secretome proteins according to signal peptides. Using the gene ontology tool, secretome proteins were categorized into different functional categories. KEGG pathway analysis identified the secreted proteins into different metabolic functional pathways. Moreover, our LC-MS/MS data revealed the secretion of various CAZymes into the extracellular milieu, which suggests its strong biotechnological applications to breakdown complex carbohydrate polymers. The identified immunodominant epitopes from the secretome of P. aeruginosa showed the characteristic of being non-allergenic, highly antigenic, nontoxic, and having a low risk of triggering autoimmune responses, which highlights their potential as successful vaccine targets. Overall, the identification of secreted proteins of P. aeruginosa could be important for both diagnostic purposes and the development of an effective candidate vaccine.
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Affiliation(s)
- Kiran Kumari
- Department of Bioengineering and Biotechnology, Birla Institute of Technology, Ranchi, 835215, India
| | - Jyotirmayee Dey
- School of Biotechnology, Deemed to Be University, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, 751024, India
| | - Soumya Ranjan Mahapatra
- School of Biotechnology, Deemed to Be University, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, 751024, India
| | - Ying Ma
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Parva Kumar Sharma
- Department of Plant Sciences and Landscape Architecture, University of Maryland, College Park, MD, 20742, USA
| | - Namrata Misra
- School of Biotechnology, Deemed to Be University, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, 751024, India
| | - Rajnish Prakash Singh
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, 201309, India.
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Paria P, Chakraborty HJ, Behera BK. Identification of novel salt tolerance-associated proteins from the secretome of Enterococcus faecalis. World J Microbiol Biotechnol 2022; 38:177. [PMID: 35934729 DOI: 10.1007/s11274-022-03354-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 07/04/2022] [Indexed: 11/30/2022]
Abstract
The ability of bacteria to adapt to the external environment is fundamental for their survival. A halotolerant microorganism Enterococcus faecalis able to grow under high salt stress conditions was isolated in the present study. The SDS-PAGE analysis of the secretome showed a protein band with a molecular weight of 28 kDa, gradually increased with an increase in salt concentration, and the highest intensity was observed at 15% salt stress condition. LC-MS/MS analysis of this particular band identified fourteen different proteins, out of which nine proteins were uncharacterized. Further, the function of uncharacterized proteins was predicted based on structure-function relationship using a reverse template search approach deciphering uncharacterized protein into type III polyketide synthases, stress-induced protein-1, Eed-h3k79me3, ba42 protein, 3-methyladenine DNA glycosylase, Atxa protein, membrane-bound respiratory hydrogenase, type-i restriction-modification system methylation subunit and ManxA. STRING network analysis further a showed strong association among the proteins. The processes predicted involvement of these proteins in signal transduction, ions transport, synthesis of the protective layer, cellular homeostasis and regulation of gene expression and different metabolic pathways. Thus, the fourteen proteins identified in the secretome play an essential role in maintaining cellular homeostasis in E. faecalis under high-salinity stress. This may represent a novel and previously unreported strategy by E. faecalis to maintain their normal growth and physiology under high salinity conditions.
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Affiliation(s)
- Prasenjit Paria
- Aquatic Environmental Biotechnology and Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700120, India
| | - Hirak Jyoti Chakraborty
- Aquatic Environmental Biotechnology and Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700120, India
| | - Bijay Kumar Behera
- Aquatic Environmental Biotechnology and Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute, Barrackpore, Kolkata, 700120, India.
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ATP7A-Regulated Enzyme Metalation and Trafficking in the Menkes Disease Puzzle. Biomedicines 2021; 9:biomedicines9040391. [PMID: 33917579 PMCID: PMC8067471 DOI: 10.3390/biomedicines9040391] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 04/01/2021] [Accepted: 04/02/2021] [Indexed: 12/12/2022] Open
Abstract
Copper is vital for numerous cellular functions affecting all tissues and organ systems in the body. The copper pump, ATP7A is critical for whole-body, cellular, and subcellular copper homeostasis, and dysfunction due to genetic defects results in Menkes disease. ATP7A dysfunction leads to copper deficiency in nervous tissue, liver, and blood but accumulation in other tissues. Site-specific cellular deficiencies of copper lead to loss of function of copper-dependent enzymes in all tissues, and the range of Menkes disease pathologies observed can now be explained in full by lack of specific copper enzymes. New pathways involving copper activated lysosomal and steroid sulfatases link patient symptoms usually related to other inborn errors of metabolism to Menkes disease. Additionally, new roles for lysyl oxidase in activation of molecules necessary for the innate immune system, and novel adapter molecules that play roles in ERGIC trafficking of brain receptors and other proteins, are emerging. We here summarize the current knowledge of the roles of copper enzyme function in Menkes disease, with a focus on ATP7A-mediated enzyme metalation in the secretory pathway. By establishing mechanistic relationships between copper-dependent cellular processes and Menkes disease symptoms in patients will not only increase understanding of copper biology but will also allow for the identification of an expanding range of copper-dependent enzymes and pathways. This will raise awareness of rare patient symptoms, and thus aid in early diagnosis of Menkes disease patients.
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Schoonover KE, Queern SL, Lapi SE, Roberts RC. Impaired copper transport in schizophrenia results in a copper-deficient brain state: A new side to the dysbindin story. World J Biol Psychiatry 2018; 21:13-28. [PMID: 30230404 PMCID: PMC6424639 DOI: 10.1080/15622975.2018.1523562] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Objectives: Several schizophrenia brain regions exhibit decreased dysbindin. Dysbindin modulates copper transport crucial for myelination, monoamine metabolism and cellular homeostasis. Schizophrenia patients (SZP) exhibit increased plasma copper, while copper-decreasing agents produce schizophrenia-like behavioural and pathological abnormalities. Therefore, we sought to determine dysbindin and copper transporter protein expression and copper content in SZP.Methods: We studied the copper-rich substantia nigra (SN) using Western blot and inductively-coupled plasma mass spectrometry. We characterised specific protein domains of copper transporters ATP7A, CTR1, ATP7B and dysbindin isoforms 1 A and 1B/C in SZP (n = 15) and matched controls (n = 11), and SN copper content in SZP (n = 14) and matched controls (n = 11). As a preliminary investigation, we compared medicated (ON; n = 11) versus unmedicated SZP (OFF; n = 4).Results: SZP exhibited increased C terminus, but not N terminus, ATP7A. SZP expressed less transmembrane CTR1 and dysbindin 1B/C than controls. ON exhibited increased C terminus ATP7A protein versus controls. OFF exhibited less N terminus ATP7A protein than controls and ON, suggesting medication-induced rescue of the ATP7A N terminus. SZP exhibited less SN copper content than controls.Conclusions: These results provide the first evidence of disrupted copper transport in schizophrenia SN that appears to result in a copper-deficient state. Furthermore, copper homeostasis may be modulated by specific dysbindin isoforms and antipsychotic treatment.
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Affiliation(s)
- Kirsten E. Schoonover
- Department of Psychology and Behavioral Neuroscience, University of Alabama at Birmingham
| | - Stacy L. Queern
- Department of Radiology, University of Alabama at Birmingham,Department of Chemistry, Washington University in St. Louis
| | - Suzanne E. Lapi
- Department of Radiology, University of Alabama at Birmingham,Department of Chemistry, Washington University in St. Louis
| | - Rosalinda C. Roberts
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
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Vallières C, Holland SL, Avery SV. Mitochondrial Ferredoxin Determines Vulnerability of Cells to Copper Excess. Cell Chem Biol 2017; 24:1228-1237.e3. [PMID: 28867595 PMCID: PMC5654725 DOI: 10.1016/j.chembiol.2017.08.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 03/02/2017] [Accepted: 08/01/2017] [Indexed: 01/17/2023]
Abstract
The essential micronutrient copper is tightly regulated in organisms, as environmental exposure or homeostasis defects can cause toxicity and neurodegenerative disease. The principal target(s) of copper toxicity have not been pinpointed, but one key effect is impaired supply of iron-sulfur (FeS) clusters to the essential protein Rli1 (ABCE1). Here, to find upstream FeS biosynthesis/delivery protein(s) responsible for this, we compared copper sensitivity of yeast-overexpressing candidate targets. Overexpression of the mitochondrial ferredoxin Yah1 produced copper hyper-resistance. 55Fe turnover assays revealed that FeS integrity of Yah1 was particularly vulnerable to copper among the test proteins. Furthermore, destabilization of the FeS domain of Yah1 produced copper hypersensitivity, and YAH1 overexpression rescued Rli1 dysfunction. This copper-resistance function was conserved in the human ferredoxin, Fdx2. The data indicate that the essential mitochondrial ferredoxin is an important copper target, determining a tipping point where plentiful copper supply becomes excessive. This knowledge could help in tackling copper-related diseases.
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Affiliation(s)
- Cindy Vallières
- School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Sara L Holland
- School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Simon V Avery
- School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
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Characterization of ATP7A missense mutants suggests a correlation between intracellular trafficking and severity of Menkes disease. Sci Rep 2017; 7:757. [PMID: 28389643 PMCID: PMC5428812 DOI: 10.1038/s41598-017-00618-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/06/2017] [Indexed: 12/12/2022] Open
Abstract
Menkes disease (MD) is caused by mutations in ATP7A, encoding a copper-transporting P-type ATPase which exhibits copper-dependent trafficking. ATP7A is found in the Trans-Golgi Network (TGN) at low copper concentrations, and in the post-Golgi compartments and the plasma membrane at higher concentrations. Here we have analyzed the effect of 36 ATP7A missense mutations identified in phenotypically different MD patients. Nine mutations identified in patients with severe MD, virtually eliminated ATP7A synthesis, in most cases due to aberrant RNA splicing. A group of 21 predominantly severe mutations led to trapping of the protein in TGN and displayed essentially no activity in a yeast-based functional assay. These were predicted to inhibit the catalytic phosphorylation of the protein. Four mutants showed diffuse post-TGN localization, while two displayed copper dependent trafficking. These six variants were identified in patients with mild MD and typically displayed activity in the yeast assay. The four post-TGN located mutants were presumably affected in the catalytic dephosphorylation of the protein. Together these results indicate that the severity of MD correlate with cellular localization of ATP7A and support previous studies indicating that phosphorylation is crucial for the exit of ATP7A from TGN, while dephosphorylation is crucial for recycling back to TGN.
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Tadini-Buoninsegni F, Smeazzetto S. Mechanisms of charge transfer in human copper ATPases ATP7A and ATP7B. IUBMB Life 2017; 69:218-225. [PMID: 28164426 DOI: 10.1002/iub.1603] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/26/2016] [Indexed: 12/30/2022]
Abstract
ATP7A and ATP7B are Cu+ -transporting ATPases of subclass IB and play a fundamental role in intracellular copper homeostasis. ATP7A/B transfer Cu+ ions across the membrane from delivery to acceptor proteins without establishing a free Cu+ gradient. Transfer of copper across the membrane is coupled to ATP hydrolysis. Current measurements on solid supported membranes (SSM) were performed to investigate the mechanism of copper-related charge transfer across ATP7A and ATP7B. SSM measurements demonstrated that electrogenic copper displacement occurs within ATP7A/B following addition of ATP and formation of the phosphorylated intermediate. Comparison of the time constants for cation displacement in ATP7A/B and sarcoplasmic reticulum Ca2+ -ATPase is consistent with the slower phosphoenzyme formation in copper ATPases. Moreover, ATP-dependent copper transfer in ATP7A/B is not affected by varying the pH, suggesting that net proton counter-transport may not occur in copper ATPases. Platinum anticancer drugs activate ATP7A/B and are subjected to ATP-dependent vectorial displacement with a mechanism analogous to that of copper. © 2016 IUBMB Life, 69(4):218-225, 2017.
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Affiliation(s)
| | - Serena Smeazzetto
- Department of Chemistry "Ugo Schiff,", University of Florence, Sesto Fiorentino, Italy
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Sautron E, Giustini C, Dang T, Moyet L, Salvi D, Crouzy S, Rolland N, Catty P, Seigneurin-Berny D. Identification of Two Conserved Residues Involved in Copper Release from Chloroplast PIB-1-ATPases. J Biol Chem 2016; 291:20136-48. [PMID: 27493208 PMCID: PMC5025697 DOI: 10.1074/jbc.m115.706978] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/04/2016] [Indexed: 01/12/2023] Open
Abstract
Copper is an essential transition metal for living organisms. In the plant model Arabidopsis thaliana, half of the copper content is localized in the chloroplast, and as a cofactor of plastocyanin, copper is essential for photosynthesis. Within the chloroplast, copper delivery to plastocyanin involves two transporters of the PIB-1-ATPases subfamily: HMA6 at the chloroplast envelope and HMA8 in the thylakoid membranes. Both proteins are high affinity copper transporters but share distinct enzymatic properties. In the present work, the comparison of 140 sequences of PIB-1-ATPases revealed a conserved region unusually rich in histidine and cysteine residues in the TMA-L1 region of eukaryotic chloroplast copper ATPases. To evaluate the role of these residues, we mutated them in HMA6 and HMA8. Mutants of interest were selected from phenotypic tests in yeast and produced in Lactococcus lactis for further biochemical characterizations using phosphorylation assays from ATP and Pi Combining functional and structural data, we highlight the importance of the cysteine and the first histidine of the CX3HX2H motif in the process of copper release from HMA6 and HMA8 and propose a copper pathway through the membrane domain of these transporters. Finally, our work suggests a more general role of the histidine residue in the transport of copper by PIB-1-ATPases.
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Affiliation(s)
- Emeline Sautron
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
| | - Cécile Giustini
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
| | - ThuyVan Dang
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
| | - Lucas Moyet
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
| | - Daniel Salvi
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
| | - Serge Crouzy
- the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the CNRS, Laboratoire de Chimie et Biologie des Métaux, UMR 5249, F-38054 Grenoble, France
| | - Norbert Rolland
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
| | - Patrice Catty
- the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the CNRS, Laboratoire de Chimie et Biologie des Métaux, UMR 5249, F-38054 Grenoble, France
| | - Daphné Seigneurin-Berny
- From the CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, F-38054 Grenoble, France, the Université Grenoble Alpes, F-38054 Grenoble, France, the CEA, DSV, BIG, F-38054 Grenoble, France, the INRA, LPCV, UMR 1417, F-38054 Grenoble, France, and
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Abstract
When we were asked to produce articles for this volume, it seemed appropriate to us to co-author an article on the history and impact of copper research in Melbourne. It is appropriate because over many years, decades in fact, we worked closely together and with Professor David Danks to identify the molecular defect in Menkes disease. This work was always carried out with the intention of understanding the nature of the copper homeostatic mechanisms and a "copper pathway" in the cell, that David had the prescience to predict must exist despite scepticism from granting agencies! He indeed inspired us to pursue research careers in this field. This article outlines some of this history.
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Affiliation(s)
- Julian F B Mercer
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Australia.
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10
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Moizard MP, Ronce N, Blesson S, Bieth E, Burglen L, Mignot C, Mortemousque I, Marmin N, Dessay B, Danesino C, Feillet F, Castelnau P, Toutain A, Moraine C, Raynaud M. Twenty-five novel mutations including duplications in the ATP7A gene. Clin Genet 2015; 79:243-53. [PMID: 21208200 DOI: 10.1111/j.1399-0004.2010.01461.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Twenty-five novel mutations including duplications in the ATP7A gene. Menkes disease (MD) and occipital horn syndrome (OHS) are allelic X-linked recessive copper deficiency disorders resulting from ATP7A gene mutations. MD is a severe condition leading to progressive neurological degeneration and death in early childhood, whereas OHS has a milder phenotype with mainly connective tissue abnormalities. Until now, molecular analyses have revealed only deletions and point mutations in both diseases. This study reports new molecular data in a series of 40 patients referred for either MD or OHS. We describe 23 point mutations (9 missense mutations, 7 splice site variants, 4 nonsense mutations, and 3 small insertions or deletions) and 7 intragenic deletions. Of these, 18 point mutations and 3 deletions are novel. Furthermore, our finding of four whole exon duplications enlarges the mutation spectrum in the ATP7A gene. ATP7A alterations were found in 85% of cases. Of these alterations, two thirds were point mutations and the remaining one third consisted of large rearrangements. We found that 66.6% of point mutations resulted in impaired ATP7A transcript splicing, a phenomenon more frequent than expected. This finding enabled us to confirm the pathogenic role of ATP7A mutations, particularly in missense and splice site variants.
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Affiliation(s)
- M-P Moizard
- CHRU de Tours, Service de Génétique, Tours, F-37044, France INSERM U930, Tours, F-37044, France CHU Hôpital Purpan, Service de Génétique médicale, Toulouse, F-31059, France CHU Hôpital d'Enfants Armand-Trousseau, AP-HP, Service de Génétique et Embryologie médicales, Paris, F-75571, France CHU Hôpital d'Enfants Armand-Trousseau, AP-HP, Service de Neuropédiatrie, Paris, F-75012, France Genetica Medica, Università di Pavia, Fondazione IRCCS S. Matteo, Pavia, I-27100, Italie Centre de Référence des Maladies Héréditaires du Métabolisme, INSERM U954. Hôpital d'Enfants, Vandoeuvre les Nancy, F-54511, France CHRU de Tours, Service de Neuropédiatrie, Tours, F-37044 France; Université François Rabelais Tours, F-37044, France
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11
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Migocka M, Posyniak E, Maciaszczyk-Dziubinska E, Papierniak A, Kosieradzaka A. Functional and Biochemical Characterization of Cucumber Genes Encoding Two Copper ATPases CsHMA5.1 and CsHMA5.2. J Biol Chem 2015; 290:15717-15729. [PMID: 25963145 PMCID: PMC4505482 DOI: 10.1074/jbc.m114.618355] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 04/29/2015] [Indexed: 11/06/2022] Open
Abstract
Plant copper P1B-type ATPases appear to be crucial for maintaining copper homeostasis within plant cells, but until now they have been studied mostly in model plant systems. Here, we present the molecular and biochemical characterization of two cucumber copper ATPases, CsHMA5.1 and CsHMA5.2, indicating a different function for HMA5-like proteins in different plants. When expressed in yeast, CsHMA5.1 and CsHMA5.2 localize to the vacuolar membrane and are activated by monovalent copper or silver ions and cysteine, showing different affinities to Cu(+) (Km ∼1 or 0.5 μM, respectively) and similar affinity to Ag(+) (Km ∼2.5 μM). Both proteins restore the growth of yeast mutants sensitive to copper excess and silver through intracellular copper sequestration, indicating that they contribute to copper and silver detoxification. Immunoblotting with specific antibodies revealed the presence of CsHMA5.1 and CsHMA5.2 in the tonoplast of cucumber cells. Interestingly, the root-specific CsHMA5.1 was not affected by copper stress, whereas the widely expressed CsHMA5.2 was up-regulated or down-regulated in roots upon copper excess or deficiency, respectively. The copper-induced increase in tonoplast CsHMA5.2 is consistent with the increased activity of ATP-dependent copper transport into tonoplast vesicles isolated from roots of plants grown under copper excess. These data identify CsHMA5.1 and CsHMA5.2 as high affinity Cu(+) transporters and suggest that CsHMA5.2 is responsible for the increased sequestration of copper in vacuoles of cucumber root cells under copper excess.
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Affiliation(s)
- Magdalena Migocka
- Institute of Experimental Biology, Department of Plant Molecular Physiology, Kanonia 6/8, 50-328 Wroclaw, Poland.
| | - Ewelina Posyniak
- Institute of Experimental Biology, Department of Plant Molecular Physiology, Kanonia 6/8, 50-328 Wroclaw, Poland
| | - Ewa Maciaszczyk-Dziubinska
- Institute of Experimental Biology, Department of Genetics and Cell Physiology, Kanonia 6/8, 50-328 Wroclaw, Poland
| | - Anna Papierniak
- Institute of Experimental Biology, Department of Plant Molecular Physiology, Kanonia 6/8, 50-328 Wroclaw, Poland
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12
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Sautron E, Mayerhofer H, Giustini C, Pro D, Crouzy S, Ravaud S, Pebay-Peyroula E, Rolland N, Catty P, Seigneurin-Berny D. HMA6 and HMA8 are two chloroplast Cu+-ATPases with different enzymatic properties. Biosci Rep 2015; 35:e00201. [PMID: 26182363 PMCID: PMC4613667 DOI: 10.1042/bsr20150065] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/01/2015] [Accepted: 04/14/2015] [Indexed: 12/16/2022] Open
Abstract
Copper (Cu) plays a key role in the photosynthetic process as cofactor of the plastocyanin (PC), an essential component of the chloroplast photosynthetic electron transfer chain. Encoded by the nuclear genome, PC is translocated in its apo-form into the chloroplast and the lumen of thylakoids where it is processed to its mature form and acquires Cu. In Arabidopsis, Cu delivery into the thylakoids involves two transporters of the PIB-1 ATPases family, heavy metal associated protein 6 (HMA6) located at the chloroplast envelope and HMA8 at the thylakoid membrane. To gain further insight into the way Cu is delivered to PC, we analysed the enzymatic properties of HMA8 and compared them with HMA6 ones using in vitro phosphorylation assays and phenotypic tests in yeast. These experiments reveal that HMA6 and HMA8 display different enzymatic properties: HMA8 has a higher apparent affinity for Cu(+) but a slower dephosphorylation kinetics than HMA6. Modelling experiments suggest that these differences could be explained by the electrostatic properties of the Cu(+) releasing cavities of the two transporters and/or by the different nature of their cognate Cu(+) acceptors (metallochaperone/PC).
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Affiliation(s)
- Emeline Sautron
- CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, 17 rue des Martyrs, F-38054 Grenoble, France
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- INRA, LPCV, USC1359, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Hubert Mayerhofer
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, Institut de Biologie Structurale, F-38044 Grenoble, France
- CNRS, Institut de Biologie Structurale, UMR5075, 71, avenue des Martyrs, F-38044 Grenoble, France
| | - Cécile Giustini
- CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, 17 rue des Martyrs, F-38054 Grenoble, France
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- INRA, LPCV, USC1359, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Danièle Pro
- CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, 17 rue des Martyrs, F-38054 Grenoble, France
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- INRA, LPCV, USC1359, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Serge Crouzy
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- *CNRS, Laboratoire de Chimie et Biologie des Métaux, UMR 5249, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Stéphanie Ravaud
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, Institut de Biologie Structurale, F-38044 Grenoble, France
- CNRS, Institut de Biologie Structurale, UMR5075, 71, avenue des Martyrs, F-38044 Grenoble, France
| | - Eva Pebay-Peyroula
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, Institut de Biologie Structurale, F-38044 Grenoble, France
- CNRS, Institut de Biologie Structurale, UMR5075, 71, avenue des Martyrs, F-38044 Grenoble, France
| | - Norbert Rolland
- CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, 17 rue des Martyrs, F-38054 Grenoble, France
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- INRA, LPCV, USC1359, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Patrice Catty
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- *CNRS, Laboratoire de Chimie et Biologie des Métaux, UMR 5249, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Daphné Seigneurin-Berny
- CNRS, Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, 17 rue des Martyrs, F-38054 Grenoble, France
- Univ. Grenoble Alpes, F-38054 Grenoble, France
- CEA, DSV, iRTSV, F-38054 Grenoble, France
- INRA, LPCV, USC1359, 17 rue des Martyrs, F-38054 Grenoble, France
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13
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Yao J, Qin Z. Counteract of bone marrow of blotchy mice against the increases of plasma copper levels induced by high-fat diets in LDLR-/- mice. J Trace Elem Med Biol 2015; 31:11-7. [PMID: 26004886 PMCID: PMC5675067 DOI: 10.1016/j.jtemb.2015.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/19/2015] [Accepted: 02/12/2015] [Indexed: 12/22/2022]
Abstract
BACKGROUND Bone marrow of blotchy mouse (blotchy marrow) reflects the function of transmembrane domain and relevant intramembrane sites of ATP7A in myeloid cells. By chronic infusion of angiotensin II, we previously found that blotchy marrow plays a minor role in regulating plasma copper. Moreover, the recipients of blotchy marrow presented a moderate reduction of plasma lipids and inflammatory mediator production. Little is known about whether these changes are a specific response to angiotensin II or reveal a more general role of ATP7A. OBJECTIVE AND DESIGN We investigated if blotchy marrow reduces plasma lipids and inflammatory mediators induced by high-fat diets. To test this hypothesis, blotchy and control marrows were reconstituted to the recipient mice (irradiated male LDLR-/- mice), followed by high-fat-diet feeding for 4 months. At the end points, plasma metals (copper, zinc and iron), lipid profiling (cholesterol, triglyceride, phospholipids and lipoprotein) and six inflammatory mediators (lymphotacin, MCP3, MCP5, TIMP1, VEGF-A and IP-10) were measured. Parallel experiments were performed using male LDLR-/- mice fed either high-fat diets or chow diets for 4 months. RESULTS In addition to hyperlipidemia and low-grade inflammation, high-fat diets selectively increased plasma copper concentration compared to chow diets in LDLR-/- mice. After high-fat-diet feeding, the recipients with blotchy marrow showed a decrease in plasma copper (p < 0.01) and an increase in plasma iron (p < 0.05). The recipients with blotchy marrow also presented decreases in cholesterol (p < 0.01) and phospholipids (p < 0.05) in plasma. Surprisingly, plasma levels of MCP3 (p < 0.05), MCP5 (p < 0.05), TIMP1 (p < 0.01), VEGF-A (p < 0.01) and IP-10 (p < 0.01) were significantly increased in the recipients with blotchy marrow compared to controls; the increased levels of MCP3, MCP5 and TIMP1 were more than 50%. CONCLUSION Our studies showed that blotchy marrow counteracts the increased copper levels induced by high-fat diets, indicating that circulating myeloid cells can regulate blood copper levels via ATP7A. Moreover, transplantation of blotchy marrow followed by high-fat diets leads to a decrease in lipid profile and an increase in inflammatory mediator production. Overall, blotchy marrow mediates divergent responses to angiotensin II and high-fat diets in vivo.
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Affiliation(s)
- Jessica Yao
- Division of Vascular Surgery, Department of Surgery, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Zhenyu Qin
- Division of Vascular Surgery, Department of Surgery, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States.
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14
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Abstract
Copper ATPases, in analogy with other members of the P-ATPase superfamily, contain a catalytic headpiece including an aspartate residue reacting with ATP to form a phosphoenzyme intermediate, and transmembrane helices containing cation-binding sites [TMBS (transmembrane metal-binding sites)] for catalytic activation and cation translocation. Following phosphoenzyme formation by utilization of ATP, bound copper undergoes displacement from the TMBS to the lumenal membrane surface, with no H+ exchange. Although PII-type ATPases sustain active transport of alkali/alkali-earth ions (i.e. Na+, Ca2+) against electrochemical gradients across defined membranes, PIB-type ATPases transfer transition metal ions (i.e. Cu+) from delivery to acceptor proteins and, prominently in mammalian cells, undergo trafficking from/to various membrane compartments. A specific component of copper ATPases is the NMBD (N-terminal metal-binding domain), containing up to six copper-binding sites in mammalian (ATP7A and ATP7B) enzymes. Copper occupancy of NMBD sites and interaction with the ATPase headpiece are required for catalytic activation. Furthermore, in the presence of copper, the NMBD allows interaction with protein kinase D, yielding phosphorylation of serine residues, ATP7B trafficking and protection from proteasome degradation. A specific feature of ATP7A is glycosylation and stabilization on plasma membranes. Cisplatin, a platinum-containing anti-cancer drug, binds to copper sites of ATP7A and ATP7B, and undergoes vectorial displacement in analogy with copper.
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15
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Smith AT, Smith KP, Rosenzweig AC. Diversity of the metal-transporting P1B-type ATPases. J Biol Inorg Chem 2014; 19:947-60. [PMID: 24729073 PMCID: PMC4119550 DOI: 10.1007/s00775-014-1129-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 03/21/2014] [Indexed: 01/23/2023]
Abstract
The P1B-ATPases are integral membrane proteins that couple ATP hydrolysis to metal cation transport. Widely distributed across all domains of life, these enzymes have been previously shown to transport copper, zinc, cobalt, and other thiophilic heavy metals. Recent data suggest that these enzymes may also be involved in nickel and/or iron transport. Here we have exploited large amounts of genomic data to examine and classify the various P1B-ATPase subfamilies. Specifically, we have combined new methods of data partitioning and network visualization known as Transitivity Clustering and Protein Similarity Networks with existing biochemical data to examine properties such as length, speciation, and metal-binding motifs of the P1B-ATPase subfamily sequences. These data reveal interesting relationships among the enzyme sequences of previously established subfamilies, indicate the presence of two new subfamilies, and suggest the existence of new regulatory elements in certain subfamilies. Taken together, these findings underscore the importance of P1B-ATPases in homeostasis of nearly every biologically relevant transition metal and provide an updated framework for future studies.
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Affiliation(s)
- Aaron T. Smith
- Departments of Molecular Biosciences and of Chemistry, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Kyle P. Smith
- Departments of Molecular Biosciences and of Chemistry, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Amy C. Rosenzweig
- Departments of Molecular Biosciences and of Chemistry, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
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16
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Scheiber IF, Mercer JF, Dringen R. Metabolism and functions of copper in brain. Prog Neurobiol 2014; 116:33-57. [DOI: 10.1016/j.pneurobio.2014.01.002] [Citation(s) in RCA: 213] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 01/08/2014] [Accepted: 01/08/2014] [Indexed: 12/15/2022]
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17
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Telianidis J, Hung YH, Materia S, Fontaine SL. Role of the P-Type ATPases, ATP7A and ATP7B in brain copper homeostasis. Front Aging Neurosci 2013; 5:44. [PMID: 23986700 PMCID: PMC3750203 DOI: 10.3389/fnagi.2013.00044] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 08/05/2013] [Indexed: 12/21/2022] Open
Abstract
Over the past two decades there have been significant advances in our understanding of copper homeostasis and the pathological consequences of copper dysregulation. Cumulative evidence is revealing a complex regulatory network of proteins and pathways that maintain copper homeostasis. The recognition of copper dysregulation as a key pathological feature in prominent neurodegenerative disorders such as Alzheimer's, Parkinson's, and prion diseases has led to increased research focus on the mechanisms controlling copper homeostasis in the brain. The copper-transporting P-type ATPases (copper-ATPases), ATP7A and ATP7B, are critical components of the copper regulatory network. Our understanding of the biochemistry and cell biology of these complex proteins has grown significantly since their discovery in 1993. They are large polytopic transmembrane proteins with six copper-binding motifs within the cytoplasmic N-terminal domain, eight transmembrane domains, and highly conserved catalytic domains. These proteins catalyze ATP-dependent copper transport across cell membranes for the metallation of many essential cuproenzymes, as well as for the removal of excess cellular copper to prevent copper toxicity. A key functional aspect of these copper transporters is their copper-responsive trafficking between the trans-Golgi network and the cell periphery. ATP7A- and ATP7B-deficiency, due to genetic mutation, underlie the inherited copper transport disorders, Menkes and Wilson diseases, respectively. Their importance in maintaining brain copper homeostasis is underscored by the severe neuropathological deficits in these disorders. Herein we will review and update our current knowledge of these copper transporters in the brain and the central nervous system, their distribution and regulation, their role in normal brain copper homeostasis, and how their absence or dysfunction contributes to disturbances in copper homeostasis and neurodegeneration.
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Affiliation(s)
- Jonathon Telianidis
- Strategic Research Centre for Molecular and Medical Research, School of Life and Environmental Sciences, Deakin UniversityBurwood, VIC, Australia
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin UniversityBurwood, VIC, Australia
| | - Ya Hui Hung
- Oxidation Biology Unit, Florey Institute of Neuroscience and Mental HealthParkville, VIC, Australia
- Centre for Neuroscience Research, The University of MelbourneParkville, VIC, Australia
| | - Stephanie Materia
- Strategic Research Centre for Molecular and Medical Research, School of Life and Environmental Sciences, Deakin UniversityBurwood, VIC, Australia
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin UniversityBurwood, VIC, Australia
| | - Sharon La Fontaine
- Strategic Research Centre for Molecular and Medical Research, School of Life and Environmental Sciences, Deakin UniversityBurwood, VIC, Australia
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin UniversityBurwood, VIC, Australia
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18
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Abstract
Copper is an essential trace metal that is required for the catalysis of several important cellular enzymes. However, since an excess of copper can also harm cells due to its potential to catalyze the generation of toxic reactive oxygen species, transport of copper and the cellular copper content are tightly regulated. This chapter summarizes the current knowledge on the importance of copper for cellular processes and on the mechanisms involved in cellular copper uptake, storage and export. In addition, we will give an overview on disturbances of copper homeostasis that are characterized by copper overload or copper deficiency or have been connected with neurodegenerative disorders.
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Affiliation(s)
- Ivo Scheiber
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
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19
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Rouached H. Recent developments in plant zinc homeostasis and the path toward improved biofortification and phytoremediation programs. PLANT SIGNALING & BEHAVIOR 2013; 8:e22681. [PMID: 23221755 PMCID: PMC3745571 DOI: 10.4161/psb.22681] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 10/25/2012] [Indexed: 05/20/2023]
Abstract
Zinc (Zn) is an essential micronutrient for all living organisms. Plants serve as a major entry point for this element into the food chain. Zn deficiency has become a widespread nutritional condition, which mirror the inadequate Zn reserves in significant proportion of the earth's arable land. A recent assessment by the World Health Organization revealed that one third of the world's population is at risk of Zn deficiency. To counter this alarming situation, substantial efforts have been made to increase Zn content and availability in staple crops and grains. Nevertheless, the absence of fundamental information has held back progress in this field. Developing a better understanding of how Zn homeostasis is regulated in plants, such as Zn transporters at loading bottlenecks, is of primary interest to biofortification and phytoremediation programs. Many reviews have been published on this subject, and here we briefly summarize the regulation of one limiting step in Zn distribution within plants - the loading of Zn into root xylem.
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20
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Zielazinski EL, Cutsail GE, Hoffman BM, Stemmler TL, Rosenzweig AC. Characterization of a cobalt-specific P(1B)-ATPase. Biochemistry 2012; 51:7891-900. [PMID: 22971227 DOI: 10.1021/bi3006708] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The P(1B)-type ATPases are a ubiquitous family of P-type ATPases involved in the transport of transition metal ions. Divided into subclasses based on sequence characteristics and substrate specificity, these integral membrane transporters play key roles in metal homeostasis, metal tolerance, and the biosynthesis of metalloproteins. The P(1B-4)-ATPases have the simplest architecture of the five P(1B)-ATPase families and have been suggested to play a role in Co(2+) transport. A P(1B-4)-ATPase from Sulfitobacter sp. NAS-14.1, designated sCoaT, has been cloned, expressed, and purified. Activity assays indicate that sCoaT is specific for Co(2+). A single Co(2+) binding site is present, and optical, electron paramagnetic resonance, and X-ray absorption spectroscopic data are consistent with tetrahedral coordination by oxygen and nitrogen ligands, including a histidine and likely a water. Surprisingly, there is no evidence for coordination by sulfur. Mutation of a conserved cysteine residue, Cys 327, in the signature transmembrane Ser-Pro-Cys metal binding motif does not abolish the ATP hydrolysis activity or affect the spectroscopic analysis, establishing that this residue is not involved in the initial Co(2+) binding by sCoaT. In contrast, replacements of conserved transmembrane residues Ser 325, His 657, Glu 658, and Thr 661 with alanine abolish ATP hydrolysis activity and Co(2+) binding, indicating that these residues are necessary for Co(2+) transport. These data represent the first in vitro characterization of a P(1B-4)-ATPase and its Co(2+) binding site.
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Affiliation(s)
- Eliza L Zielazinski
- Departments of Molecular Biosciences and Chemistry, Northwestern University, Evanston, Illinois 60208, USA
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21
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León-García G, Santana A, Villegas-Sepúlveda N, Pérez-González C, Henrríquez-Esquíroz JM, de León-García C, Wong C, Baeza I. The T1048I mutation in ATP7A gene causes an unusual Menkes disease presentation. BMC Pediatr 2012; 12:150. [PMID: 22992316 PMCID: PMC3489546 DOI: 10.1186/1471-2431-12-150] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Accepted: 08/17/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The ATP7A gene encodes the ATP7A protein, which is a trans-Golgi network copper transporter expressed in the brain and other organs. Mutations in this gene cause disorders of copper metabolism, such as Menkes disease. Here we describe the novel and unusual mutation (p.T1048I) in the ATP7A gene of a child with Menkes disease. The mutation affects a conserved DKTGT1048 phosphorylation motif that is involved in the catalytic activity of ATP7A. We also describe the clinical course and the response to copper treatment in this patient. CASE PRESENTATION An 11-month-old male Caucasian infant was studied because of hypotonia, ataxia and global developmental delay. The patient presented low levels of serum copper and ceruloplasmin, and was shown to be hemizygous for the p.T1048I mutation in ATP7A. The diagnosis was confirmed when the patient was 18 months old, and treatment with copper-histidinate (Cu-His) was started immediately. The patient showed some neurological improvement and he is currently 8 years old. Because the p.T1048I mutation affects its catalytic site, we expected a complete loss of functional ATP7A and a classical Menkes disease presentation. However, the clinical course of the patient was mild, and he responded to Cu-His treatment, which suggests that this mutation leads to partial conservation of the activity of ATP7A. CONCLUSION This case emphasizes the important correlation between genotype and phenotype in patients with Menkes disease. The prognosis in Menkes disease is associated with early detection, early initiation of treatment and with the preservation of some ATP7A activity, which is necessary for Cu-His treatment response. The description of this new mutation and the response of the patient to Cu-His treatment will contribute to the growing body of knowledge about treatment response in Menkes disease.
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Affiliation(s)
- Gregorio León-García
- Department of Biochemistry, National School of Biological Sciences, National Polytechnic Institute (IPN), Mexico City, 11340, Mexico
| | - Alfredo Santana
- Centre for Biomedical Research on Rare Disease (CIBERER), Canarias University Hospital, Institute of Biomedical Technologies, University of La Laguna, Tenerife, Spain
| | - Nicolás Villegas-Sepúlveda
- Department of Molecular Biology, Centre for Research and Advanced Studies, IPN, Mexico City, 07360, Mexico
| | | | | | | | - Carlos Wong
- Department of Biochemistry, National School of Biological Sciences, National Polytechnic Institute (IPN), Mexico City, 11340, Mexico
| | - Isabel Baeza
- Department of Biochemistry, National School of Biological Sciences, National Polytechnic Institute (IPN), Mexico City, 11340, Mexico
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22
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Rosenzweig AC, Argüello JM. Toward a molecular understanding of metal transport by P(1B)-type ATPases. CURRENT TOPICS IN MEMBRANES 2012; 69:113-36. [PMID: 23046649 DOI: 10.1016/b978-0-12-394390-3.00005-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The P(1B) family of P-type ATPases couples the transport of cytoplasmic transition metals across biological membranes to the hydrolysis of ATP. These ubiquitous transporters function in maintaining cytoplasmic metal quotas and in the assembly of metalloproteins, and have been classified into subfamilies (P(1B-1)-P(1B-5)) on the basis of their transported substrates (Cu(+), Zn(2+), Cu(2+), and Co(2+)) and signature sequences in their transmembrane segments. In addition, each subgroup presents a characteristic membrane topology and specific regulatory cytoplasmic metal-binding domains. In recent years, significant major aspects of their transport mechanism have been described, including the stoichiometry of transport and the delivery of substrates to transport sites by metallochaperones. Toward understanding their structure, the metal coordination by transport sites has been characterized for Cu(+) and Zn(2+)-ATPases. In addition, atomic resolution structures have been determined, providing key insight into the elements that enable transition metal transport. Because the Cu(+)-transporting ATPases are found in humans and are linked to disease, this subfamily has been the focus of intense study. As a result, significant progress has been made toward understanding Cu(+)-ATPase function on the molecular level, using both the human proteins and the bacterial homologs, most notably the CopA proteins from Archaeoglobus fulgidus, Bacillus subtilis, and Thermotoga maritima. This chapter thus focuses on the mechanistic and structural information obtained by studying these latter Cu(+)-ATPases, with some consideration of how these aspects might differ for the other subfamilies of P(1B)-ATPases.
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Affiliation(s)
- Amy C Rosenzweig
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA.
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23
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Migocka M, Papierniak A, Kosatka E, Klobus G. Comparative study of the active cadmium efflux systems operating at the plasma membrane and tonoplast of cucumber root cells. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:4903-16. [PMID: 21705389 PMCID: PMC3193004 DOI: 10.1093/jxb/err180] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 03/30/2011] [Accepted: 05/03/2011] [Indexed: 05/07/2023]
Abstract
The strategies developed by plants to avoid the toxicity of cadmium (Cd) and other heavy metals involve active sequestration of metals into the apoplast and vacuoles. The protein systems excluding heavy metals from the cell cytosol localize to the plasma membrane and tonoplast and are energized either by ATP or by the electrochemical gradient generated by H(+)-ATPase or by V-ATPase and pyrophosphatase (PPase), respectively. In this work, a comparative study on the contribution of both the plasma membrane and tonoplast in the active detoxification of plant cells after treatment with Cd was performed. The studies using plants treated and untreated with Cd reveal that both, H(+)-coupled and MgATP-driven efflux of Cd across plasma membranes and tonoplast is markedly stimulated in the presence of Cd in the environment. Previous studies on plasma-membrane localized H(+)-coupled Cd efflux together with the present data demonstrating tonoplast H(+)/Cd(2+) antiport activity suggest that H(+)-coupled secondary transport of Cd displays a lower affinity for Cd when compared with Cd primary pumps driven by MgATP. In addition, it is shown that MgATP-energized Cd efflux across both membranes is significantly enhanced by cysteine, dithiothreitol, and glutathione. These results suggest that Cd is excluded from the cytosol through an energy-dependent system as a free ion as well as a complexed form. Although both membranes contribute in the active exclusion of ionized and complexed Cd from the cytosol, the overall calculation of Cd accumulation in the everted plasma membranes and vacuolar vesicles suggests that the tonoplast and vacuole have a major function in Cd efflux from the cytosol in the roots of cucumber subjected to Cd stress.
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Affiliation(s)
- Magdalena Migocka
- Wroclaw University, Institute of Plant Biology, Department of Plant Physiology, Kanonia 6/8, 50-328 Wroclaw, Poland.
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24
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Catty P, Boutigny S, Miras R, Joyard J, Rolland N, Seigneurin-Berny D. Biochemical characterization of AtHMA6/PAA1, a chloroplast envelope Cu(I)-ATPase. J Biol Chem 2011; 286:36188-97. [PMID: 21878617 DOI: 10.1074/jbc.m111.241034] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Copper is an essential plant micronutrient playing key roles in cellular processes, among them photosynthesis. In Arabidopsis thaliana, copper delivery to chloroplasts, mainly studied by genetic approaches, is thought to involve two P(IB)-type ATPases: AtHMA1 and AtHMA6/PAA1. The lack of biochemical characterization of AtHMA1 and PAA1, and more generally of plant P(IB)-type ATPases, is due to the difficulty of getting high amounts of these membrane proteins in an active form, either from their native environment or after expression in heterologous systems. In this study, we report the first biochemical characterization of PAA1, a plant copper-transporting ATPase. PAA1 produced in Lactococcus lactis is active, forming an aspartyl phosphate intermediate in the presence of ATP and the adequate metal ion. PAA1 can also be phosphorylated using inorganic phosphate in the absence of transition metal. Both phosphorylation types allowed us to demonstrate that PAA1 is activated by monovalent copper ions (and to a lower extent by silver ions) with an apparent affinity in the micromolar range. In agreement with these biochemical data, we also demonstrate that when expressed in yeast, PAA1 induces increased sensitivities to copper and silver. These data provide the first enzymatic characterization of a P(IB-1)-type plant ATPase and clearly identify PAA1 as a high affinity Cu(I) transporter of the chloroplast envelope.
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Affiliation(s)
- Patrice Catty
- Laboratoire de Chimie et Biologie des Métaux, UMR5249, CNRS, F-38054 Grenoble, France
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25
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Inesi G. Calcium and copper transport ATPases: analogies and diversities in transduction and signaling mechanisms. J Cell Commun Signal 2011; 5:227-37. [PMID: 21656155 PMCID: PMC3145875 DOI: 10.1007/s12079-011-0136-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 04/28/2011] [Indexed: 12/17/2022] Open
Abstract
The calcium transport ATPase and the copper transport ATPase are members of the P-ATPase family and retain an analogous catalytic mechanism for ATP utilization, including intermediate phosphoryl transfer to a conserved aspartyl residue, vectorial displacement of bound cation, and final hydrolytic cleavage of Pi. Both ATPases undergo protein conformational changes concomitant with catalytic events. Yet, the two ATPases are prototypes of different features with regard to transduction and signaling mechanisms. The calcium ATPase resides stably on membranes delimiting cellular compartments, acquires free Ca2+ with high affinity on one side of the membrane, and releases the bound Ca2+ on the other side of the membrane to yield a high free Ca2+ gradient. These features are a basic requirement for cellular Ca2+ signaling mechanisms. On the other hand, the copper ATPase acquires copper through exchange with donor proteins, and undergoes intracellular trafficking to deliver copper to acceptor proteins. In addition to the cation transport site and the conserved aspartate undergoing catalytic phosphorylation, the copper ATPase has copper binding regulatory sites on a unique N-terminal protein extension, and has also serine residues undergoing kinase assisted phosphorylation. These additional features are involved in the mechanism of copper ATPase intracellular trafficking which is required to deliver copper to plasma membranes for extrusion, and to the trans-Golgi network for incorporation into metalloproteins. Isoform specific glyocosylation contributes to stabilization of ATP7A copper ATPase in plasma membranes.
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Affiliation(s)
- Giuseppe Inesi
- California Pacific Medical Center Research Institute, 475 Brannan Street, San Francisco, CA, 94107, USA,
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26
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Barry AN, Otoikhian A, Bhatt S, Shinde U, Tsivkovskii R, Blackburn NJ, Lutsenko S. The lumenal loop Met672-Pro707 of copper-transporting ATPase ATP7A binds metals and facilitates copper release from the intramembrane sites. J Biol Chem 2011; 286:26585-94. [PMID: 21646353 DOI: 10.1074/jbc.m111.229039] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The copper-transporting ATPase ATP7A has an essential role in human physiology. ATP7A transfers the copper cofactor to metalloenzymes within the secretory pathway; inactivation of ATP7A results in an untreatable neurodegenerative disorder, Menkes disease. Presently, the mechanism of ATP7A-mediated copper release into the secretory pathway is not understood. We demonstrate that the characteristic His/Met-rich segment Met(672)-Pro(707) (HM-loop) that connects the first two transmembrane segments of ATP7A is important for copper release. Mutations within this loop do not prevent the ability of ATP7A to form a phosphorylated intermediate during ATP hydrolysis but inhibit subsequent dephosphorylation, a step associated with copper release. The HM-loop inserted into a scaffold protein forms two structurally distinct binding sites and coordinates copper in a mixed His-Met environment with an ∼2:1 stoichiometry. Binding of either copper or silver, a Cu(I) analog, induces structural changes in the loop. Mutations of 4 Met residues to Ile or two His-His pairs to Ala-Gly decrease affinity for copper. Altogether, the data suggest a two-step process, where copper released from the transport sites binds to the first His(Met)(2) site, triggering a structural change and binding to a second 2-coordinate His-His or His-Met site. We also show that copper binding within the HM-loop stabilizes Cu(I) and protects it from oxidation, which may further aid the transfer of copper from ATP7A to acceptor proteins. The mechanism of copper entry into the secretory pathway is discussed.
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Affiliation(s)
- Amanda N Barry
- From the Department of Physiology, Johns Hopkins University, Baltimore, Maryland 21205, USA
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In silico modeling of the Menkes copper-translocating P-type ATPase 3rd metal binding domain predicts that phosphorylation regulates copper-binding. Biometals 2011; 24:477-87. [DOI: 10.1007/s10534-011-9410-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 01/06/2011] [Indexed: 12/17/2022]
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Banci L, Bertini I, Cantini F, Ciofi-Baffoni S. Cellular copper distribution: a mechanistic systems biology approach. Cell Mol Life Sci 2010; 67:2563-89. [PMID: 20333435 PMCID: PMC11115773 DOI: 10.1007/s00018-010-0330-x] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Revised: 01/27/2010] [Accepted: 02/22/2010] [Indexed: 01/01/2023]
Abstract
Copper is an essential but potentially harmful trace element required in many enzymatic processes involving redox chemistry. Cellular copper homeostasis in mammals is predominantly maintained by regulating copper transport through the copper import CTR proteins and the copper exporters ATP7A and ATP7B. Once copper is imported into the cell, several pathways involving a number of copper proteins are responsible for trafficking it specifically where it is required for cellular life, thus avoiding the release of harmful free copper ions. In this study we review recent progress made in understanding the molecular mechanisms of copper transport in cells by analyzing structural features of copper proteins, their mode of interaction, and their thermodynamic and kinetic parameters, thus contributing to systems biology of copper within the cell.
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Affiliation(s)
- Lucia Banci
- Department of Chemistry, Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence Italy
| | - Ivano Bertini
- Department of Chemistry, Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence Italy
| | - Francesca Cantini
- Department of Chemistry, Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence Italy
| | - Simone Ciofi-Baffoni
- Department of Chemistry, Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence Italy
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29
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Baekgaard L, Mikkelsen MD, Sørensen DM, Hegelund JN, Persson DP, Mills RF, Yang Z, Husted S, Andersen JP, Buch-Pedersen MJ, Schjoerring JK, Williams LE, Palmgren MG. A combined zinc/cadmium sensor and zinc/cadmium export regulator in a heavy metal pump. J Biol Chem 2010; 285:31243-52. [PMID: 20650903 DOI: 10.1074/jbc.m110.111260] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Heavy metal pumps (P1B-ATPases) are important for cellular heavy metal homeostasis. AtHMA4, an Arabidopsis thaliana heavy metal pump of importance for plant Zn(2+) nutrition, has an extended C-terminal domain containing 13 cysteine pairs and a terminal stretch of 11 histidines. Using a novel size-exclusion chromatography, inductively coupled plasma mass spectrometry approach we report that the C-terminal domain of AtHMA4 is a high affinity Zn(2+) and Cd(2+) chelator with capacity to bind 10 Zn(2+) ions per C terminus. When AtHMA4 is expressed in a Zn(2+)-sensitive zrc1 cot1 yeast strain, sequential removal of the histidine stretch and the cysteine pairs confers a gradual increase in Zn(2+) and Cd(2+) tolerance and lowered Zn(2+) and Cd(2+) content of transformed yeast cells. We conclude that the C-terminal domain of AtHMA4 serves a dual role as Zn(2+) and Cd(2+) chelator (sensor) and as a regulator of the efficiency of Zn(2+) and Cd(2+) export. The identification of a post-translational handle on Zn(2+) and Cd(2+) transport efficiency opens new perspectives for regulation of Zn(2+) nutrition and tolerance in eukaryotes.
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Affiliation(s)
- Lone Baekgaard
- Department of Plant Biology and Biotechnology, Centre for Membrane Pumps in Cells and Disease, PUMPKIN, Danish National Research Foundation, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
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30
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Luoma LM, Deeb TM, Macintyre G, Cox DW. Functional analysis of mutations in the ATP loop of the Wilson disease copper transporter, ATP7B. Hum Mutat 2010; 31:569-77. [DOI: 10.1002/humu.21228] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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Rodriguez-Granillo A, Crespo A, Wittung-Stafshede P. Interdomain Interactions Modulate Collective Dynamics of the Metal-Binding Domains in the Wilson Disease Protein. J Phys Chem B 2010; 114:1836-48. [DOI: 10.1021/jp909450x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Agustina Rodriguez-Granillo
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251, Department of Bioengineering, Rice University, Houston, Texas 77005, and Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Alejandro Crespo
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251, Department of Bioengineering, Rice University, Houston, Texas 77005, and Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Pernilla Wittung-Stafshede
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251, Department of Bioengineering, Rice University, Houston, Texas 77005, and Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
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33
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Banci L, Bertini I, Cantini F, Inagaki S, Migliardi M, Rosato A. The binding mode of ATP revealed by the solution structure of the N-domain of human ATP7A. J Biol Chem 2009; 285:2537-44. [PMID: 19917612 DOI: 10.1074/jbc.m109.054262] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the solution NMR structures of the N-domain of the Menkes protein (ATP7A) in the ATP-free and ATP-bound forms. The structures consist of a twisted antiparallel six-stranded beta-sheet flanked by two pairs of alpha-helices. A protein loop of 50 amino acids located between beta 3 and beta 4 is disordered and mobile on the subnanosecond time scale. ATP binds with an affinity constant of (1.2 +/- 0.1) x 10(4) m(-1) and exchanges with a rate of the order of 1 x 10(3) s(-1). The ATP-binding cavity is considerably affected by the presence of the ligand, resulting in a more compact conformation in the ATP-bound than in the ATP-free form. This structural variation is due to the movement of the alpha1-alpha2 and beta2-beta 3 loops, both of which are highly conserved in copper(I)-transporting P(IB)-type ATPases. The present structure reveals a characteristic binding mode of ATP within the protein scaffold of the copper(I)-transporting P(IB)-type ATPases with respect to the other P-type ATPases. In particular, the binding cavity contains mainly hydrophobic aliphatic residues, which are involved in van der Waal's interactions with the adenine ring of ATP, and a Glu side chain, which forms a crucial hydrogen bond to the amino group of ATP.
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Affiliation(s)
- Lucia Banci
- Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, Italy
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34
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van den Berghe PVE, Klomp LWJ. Posttranslational regulation of copper transporters. J Biol Inorg Chem 2009; 15:37-46. [DOI: 10.1007/s00775-009-0592-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 09/10/2009] [Indexed: 12/15/2022]
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35
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Morin I, Gudin S, Mintz E, Cuillel M. Dissecting the role of the N-terminal metal-binding domains in activating the yeast copper ATPasein vivo. FEBS J 2009; 276:4483-95. [DOI: 10.1111/j.1742-4658.2009.07155.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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36
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Zhang Y, Gladyshev VN. Comparative Genomics of Trace Elements: Emerging Dynamic View of Trace Element Utilization and Function. Chem Rev 2009; 109:4828-61. [DOI: 10.1021/cr800557s] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Yan Zhang
- Department of Biochemistry and Redox Biology Center, University of Nebraska, Lincoln, Nebraska 68588-0664
| | - Vadim N. Gladyshev
- Department of Biochemistry and Redox Biology Center, University of Nebraska, Lincoln, Nebraska 68588-0664
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37
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Affiliation(s)
- Deenah Osman
- Life Sciences, University of Manchester, Manchester, United Kingdom
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38
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Banci L, Bertini I, Cantini F, Massagni C, Migliardi M, Rosato A. An NMR study of the interaction of the N-terminal cytoplasmic tail of the Wilson disease protein with copper(I)-HAH1. J Biol Chem 2009; 284:9354-60. [PMID: 19181666 PMCID: PMC2666587 DOI: 10.1074/jbc.m805981200] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 01/30/2009] [Indexed: 12/17/2022] Open
Abstract
ATP7B is a human P(1B)-type ATPase that has a crucial role in maintaining copper(I) homeostasis. Mutations in the corresponding gene are the cause of Wilson disease. Among its various distinguishing features is a long ( approximately 630 amino acids) N-terminal cytosolic tail containing six domains that are individually folded and capable of binding one copper(I) ion each. We expressed the entire tail as a single construct in Escherichia coli and investigated its interaction with its copper chaperone (i.e. HAH1) by solution NMR spectroscopy. We observed that all six of the metal-binding domains were metallated by Cu(I)-HAH1, with the first, the second, and the fourth domains forming an adduct with it. This behavior is different from that of the highly similar human ATPase ATP7A, in which only two domains form such an adduct. The distinct behaviors of the different domains were analyzed in terms of the energetics of Cu(I) transfer, hinting at a specific role of the interaction with copper(I)-HAH1 in the overall functional process.
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Affiliation(s)
- Lucia Banci
- Magnetic Resonance Center, University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy
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39
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The multi-layered regulation of copper translocating P-type ATPases. Biometals 2009; 22:177-90. [PMID: 19130269 DOI: 10.1007/s10534-008-9183-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Accepted: 12/07/2008] [Indexed: 12/21/2022]
Abstract
The copper-translocating Menkes (ATP7A, MNK protein) and Wilson (ATP7B, WND protein) P-type ATPases are pivotal for copper (Cu) homeostasis, functioning in the biosynthetic incorporation of Cu into copper-dependent enzymes of the secretory pathway, Cu detoxification via Cu efflux, and specialized roles such as systemic Cu absorption (MNK) and Cu excretion (WND). Essential to these functions is their Cu and hormone-responsive distribution between the trans-Golgi network (TGN) and exocytic vesicles located at or proximal to the apical (WND) or basolateral (MNK) cell surface. Intriguingly, MNK and WND Cu-ATPases expressed in the same tissues perform distinct yet complementary roles. While intramolecular differences may specify their distinct roles, cellular signaling components are predicted to be critical for both differences and synergy between these enzymes. This review focuses on these mechanisms, including the cell signaling pathways that influence trafficking and bi-functionality of Cu-ATPases. Phosphorylation events are hypothesized to play a central role in Cu homeostasis, promoting multi-layered regulation and cross-talk between cuproenzymes and Cu-independent mechanisms.
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40
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Wong CKE, Jarvis RS, Sherson SM, Cobbett CS. Functional analysis of the heavy metal binding domains of the Zn/Cd-transporting ATPase, HMA2, in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2009; 181:79-88. [PMID: 19076719 DOI: 10.1111/j.1469-8137.2008.02637.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The Zn/Cd-transporting ATPase, HMA2, has N- and C-terminal domains that can bind Zn ions with high affinity. Mutant derivatives were generated to determine the significance of these domains to HMA2 function in planta. Mutant derivatives, with and without a C-terminal GFP tag, were expressed from the HMA2 promoter in transgenic hma2,hma4, Zn-deficient, plants to test for functionality. A deletion mutant lacking the C-terminal 244 amino acids rescued most of the hma2,hma4 Zn-deficiency phenotypes with the exception of embryo or seed development. Root-to-shoot Cd translocation was fully rescued. The GFP-tagged derivative was partially mis-localized in the root pericycle cells in which it was expressed. Deletion derivatives lacking the C-terminal 121 and 21 amino acids rescued all phenotypes and localized normally. N-terminal domain mutants localized normally but failed to complement the hma2,hma4 phenotypes. These observations suggest that the N-terminal domain of HMA2 is essential for function in planta while the C-terminal domain, although not essential for function, may contain a signal important for the subcellular localization of the protein.
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Affiliation(s)
| | - Renée S Jarvis
- Department of Genetics, The University of Melbourne, Parkville, Australia, 3010
| | - Sarah M Sherson
- Department of Genetics, The University of Melbourne, Parkville, Australia, 3010
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41
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Wong CKE, Cobbett CS. HMA P-type ATPases are the major mechanism for root-to-shoot Cd translocation in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2009; 181:71-78. [PMID: 19076718 DOI: 10.1111/j.1469-8137.2008.02638.x] [Citation(s) in RCA: 247] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The Zn/Cd-transporting ATPases, HMA2 and HMA4, essential for root-to-shoot Zn translocation, are also able to transport Cd. Phytochelatins (PCs) are a major mechanism of Cd detoxification through the sequestration of PC-Cd complexes in vacuoles. The roles of HMA2 and HMA4 in root-to-shoot Cd translocation and Cd tolerance were investigated in the PC-deficient, cad1-3 mutant and CAD1 backgrounds. Six lines, with all possible combinations of hma2, hma4 and cad1 mutations, were constructed. The lines were tested for Cd-sensitivity on agar medium, and radioactive (109)Cd was used to measure Cd uptake and translocation from root to shoot over periods of up to 6 d. In hma4 and hma2,hma4, but not hma2, root-to-shoot Cd translocation was decreased to about 60 and 2%, respectively, of that in the wild-type. Cd sensitivity increased approximately twofold in the hma2,hma4 mutant in both CAD1 and cad1 backgrounds. PC deficiency resulted in an increase in shoot Cd concentrations. The near-complete abolition of root-to-shoot Cd translocation resulting from the loss of function of HMA2 and HMA4 demonstrates they are the major mechanism for Cd translocation in Arabidopsis thaliana.
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42
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Lutsenko S, Barnes NL, Bartee MY, Dmitriev OY. Function and regulation of human copper-transporting ATPases. Physiol Rev 2007; 87:1011-46. [PMID: 17615395 DOI: 10.1152/physrev.00004.2006] [Citation(s) in RCA: 545] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Copper-transporting ATPases (Cu-ATPases) ATP7A and ATP7B are evolutionarily conserved polytopic membrane proteins with essential roles in human physiology. The Cu-ATPases are expressed in most tissues, and their transport activity is crucial for central nervous system development, liver function, connective tissue formation, and many other physiological processes. The loss of ATP7A or ATP7B function is associated with severe metabolic disorders, Menkes disease, and Wilson disease. In cells, the Cu-ATPases maintain intracellular copper concentration by transporting copper from the cytosol across cellular membranes. They also contribute to protein biosynthesis by delivering copper into the lumen of the secretory pathway where metal ion is incorporated into copper-dependent enzymes. The biosynthetic and homeostatic functions of Cu-ATPases are performed in different cell compartments; targeting to these compartments and the functional activity of Cu-ATPase are both regulated by copper. In recent years, significant progress has been made in understanding the structure, function, and regulation of these essential transporters. These studies raised many new questions related to specific physiological roles of Cu-ATPases in various tissues and complex mechanisms that control the Cu-ATPase function. This review summarizes current data on the structural organization and functional properties of ATP7A and ATP7B as well as their localization and functions in various tissues, and discusses the current models of regulated trafficking of human Cu-ATPases.
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Affiliation(s)
- Svetlana Lutsenko
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon 97239, USA.
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43
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de Bie P, Muller P, Wijmenga C, Klomp LWJ. Molecular pathogenesis of Wilson and Menkes disease: correlation of mutations with molecular defects and disease phenotypes. J Med Genet 2007; 44:673-88. [PMID: 17717039 PMCID: PMC2752173 DOI: 10.1136/jmg.2007.052746] [Citation(s) in RCA: 244] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The trace metal copper is essential for a variety of biological processes, but extremely toxic when present in excessive amounts. Therefore, concentrations of this metal in the body are kept under tight control. Central regulators of cellular copper metabolism are the copper-transporting P-type ATPases ATP7A and ATP7B. Mutations in ATP7A or ATP7B disrupt the homeostatic copper balance, resulting in copper deficiency (Menkes disease) or copper overload (Wilson disease), respectively. ATP7A and ATP7B exert their functions in copper transport through a variety of interdependent mechanisms and regulatory events, including their catalytic ATPase activity, copper-induced trafficking, post-translational modifications and protein-protein interactions. This paper reviews the extensive efforts that have been undertaken over the past few years to dissect and characterise these mechanisms, and how these are affected in Menkes and Wilson disease. As both disorders are characterised by an extensive clinical heterogeneity, we will discus how the underlying genetic defects correlate with the molecular functions of ATP7A and ATP7B and with the clinical expression of these disorders.
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Affiliation(s)
- P de Bie
- Laboratory of Metabolic and Endocrine Diseases, Room KC.02.069.1, Lundlaan 6, 3584 EA Utrecht, The Netherlands
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44
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Lutsenko S, LeShane ES, Shinde U. Biochemical basis of regulation of human copper-transporting ATPases. Arch Biochem Biophys 2007; 463:134-48. [PMID: 17562324 PMCID: PMC2025638 DOI: 10.1016/j.abb.2007.04.013] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 04/10/2007] [Accepted: 04/13/2007] [Indexed: 12/11/2022]
Abstract
Copper is essential for cell metabolism as a cofactor of key metabolic enzymes. The biosynthetic incorporation of copper into secreted and plasma membrane-bound proteins requires activity of the copper-transporting ATPases (Cu-ATPases) ATP7A and ATP7B. The Cu-ATPases also export excess copper from the cell and thus critically contribute to the homeostatic control of copper. The trafficking of Cu-ATPases from the trans-Golgi network to endocytic vesicles in response to various signals allows for the balance between the biosynthetic and copper exporting functions of these transporters. Although significant progress has been made towards understanding the biochemical characteristics of human Cu-ATPase, the mechanisms that control their function and intracellular localization remain poorly understood. In this review, we summarize current information on structural features and functional properties of ATP7A and ATP7B. We also describe sequence motifs unique for each Cu-ATPase and speculate about their role in regulating ATP7A and ATP7B activity and trafficking.
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Affiliation(s)
- Svetlana Lutsenko
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA.
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45
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La Fontaine S, Mercer JFB. Trafficking of the copper-ATPases, ATP7A and ATP7B: Role in copper homeostasis. Arch Biochem Biophys 2007; 463:149-67. [PMID: 17531189 DOI: 10.1016/j.abb.2007.04.021] [Citation(s) in RCA: 300] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Revised: 04/18/2007] [Accepted: 04/18/2007] [Indexed: 01/05/2023]
Abstract
Copper is essential for human health and copper imbalance is a key factor in the aetiology and pathology of several neurodegenerative diseases. The copper-transporting P-type ATPases, ATP7A and ATP7B are key molecules required for the regulation and maintenance of mammalian copper homeostasis. Their absence or malfunction leads to the genetically inherited disorders, Menkes and Wilson diseases, respectively. These proteins have a dual role in cells, namely to provide copper to essential cuproenzymes and to mediate the excretion of excess intracellular copper. A unique feature of ATP7A and ATP7B that is integral to these functions is their ability to sense and respond to intracellular copper levels, the latter manifested through their copper-regulated trafficking from the transGolgi network to the appropriate cellular membrane domain (basolateral or apical, respectively) to eliminate excess copper from the cell. Research over the last decade has yielded significant insight into the enzymatic properties and cell biology of the copper-ATPases. With recent advances in elucidating their localization and trafficking in human and animal tissues in response to physiological stimuli, we are progressing rapidly towards an integrated understanding of their physiological significance at the level of the whole animal. This knowledge in turn is helping to clarify the biochemical and cellular basis not only for the phenotypes conferred by individual Menkes and Wilson disease patient mutations, but also for the clinical variability of phenotypes associated with each of these diseases. Importantly, this information is also providing a rational basis for the applicability and appropriateness of certain diagnostic markers and therapeutic regimes. This overview will provide an update on the current state of our understanding of the localization and trafficking properties of the copper-ATPases in cells and tissues, the molecular signals and posttranslational interactions that govern their trafficking activities, and the cellular basis for the clinical phenotypes associated with disease-causing mutations.
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Affiliation(s)
- Sharon La Fontaine
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, 221 Burwood Highway, Burwood, Vic. 3125, Australia.
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46
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Eren E, González-Guerrero M, Kaufman BM, Argüello JM. Novel Zn2+ Coordination by the Regulatory N-Terminus Metal Binding Domain of Arabidopsis thaliana Zn2+-ATPase HMA2. Biochemistry 2007; 46:7754-64. [PMID: 17550234 DOI: 10.1021/bi7001345] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Arabidopsis thaliana HMA2 is a Zn2+ transporting P1B-type ATPase required for maintaining plant metal homeostasis. HMA2 and all eukaryote Zn2+-ATPases have unique conserved N- and C-terminal sequences that differentiate them from other P1B-type ATPases. Homology modeling and structural comparison by circular dichroism indicate that the 75 amino acid long HMA2 N-terminus shares the betaalphabetabetaalpha folding present in most P1B-type ATPase N-terminal metal binding domains (N-MBDs). However, the characteristic metal binding sequence CysXXCys is replaced by Cys17CysXXGlu21, a sequence present in all plant Zn2+-ATPases. The isolated HMA2 N-MBD fragment binds a single Zn2+ (Kd 0.18 microM), Cd2+ (Kd 0.27 microM), or, with less affinity, Cu+ (Kd 13 microM). Mutagenesis studies indicate that Cys17, Cys18, and Glu21 participate in Zn2+ and Cd2+ coordination, while Cys17 and Glu21, but not Cys18, are required for Cu+ binding. Interestingly, the Glu21Cys mutation that generates a CysCysXXCys site is unable to bind Zn2+ or Cd2+ but it binds Cu+ with affinity (Kd 1 microM) higher than wild type N-MBD. Truncated HMA2 lacking the N-MBD showed reduced ATPase activity without significant changes in metal binding to transmembrane metal binding sites. Likewise, ATPase activity of HMA2 carrying mutations Cys17Ala, Cys18Ala, and Glu21Ala/Cys was also reduced but showed a metal dependence similar to the wild type enzyme. These observations suggest that plant Zn2+-ATPase N-MBDs have a folding and function similar to Cu+-ATPase N-MBDs. However, the unique Zn2+ coordination via two thiols and a carboxyl group provides selective binding of the activating metals to these regulatory domains. Metal binding through these side chains, although found in different sequences, appears as a common feature of both bacterial and eukaryotic Zn2+-ATPase N-MBDs.
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Affiliation(s)
- Elif Eren
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA
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47
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Yang Y, Mandal AK, Bredeston LM, González-Flecha FL, Argüello JM. Activation of Archaeoglobus fulgidus Cu+-ATPase CopA by cysteine. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:495-501. [PMID: 17064659 DOI: 10.1016/j.bbamem.2006.09.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 09/13/2006] [Accepted: 09/18/2006] [Indexed: 11/21/2022]
Abstract
CopA, a thermophilic ATPase from Archaeoglobus fulgidus, drives the outward movement of Cu(+) across the cell membrane. Millimolar concentration of Cys dramatically increases ( congruent with 800%) the activity of CopA and other P(IB)-type ATPases (Escherichia coli ZntA and Arabidopsis thaliana HMA2). The high affinity of CopA for metal ( congruent with 1 microM) together with the low Cu(+)-Cys K(D) (<10(-10)M) suggested a multifaceted interaction of Cys with CopA, perhaps acting as a substitute for the Cu(+) chaperone protein present in vivo. To explain the activation by the amino acid and further understand the mechanism of metal delivery to transport ATPases, Cys effects on the turnover and partial reactions of CopA were studied. 2-20 mM Cys accelerates enzyme turnover with little effect on CopA affinity for Cu(+), suggesting a metal independent activation. Furthermore, Cys activates the p-nitrophenyl phosphatase activity of CopA, even though this activity is metal independent. Cys accelerates enzyme phosphorylation and the forward dephosphorylation rates yielding higher steady state phosphoenzyme levels. The faster dephosphorylation would explain the higher enzyme turnover in the presence of Cys. The amino acid has no significant effect on low affinity ATP K(m) suggesting no changes in the E(1)<-->E(2) equilibrium. Characterization of Cu(+) transport into sealed vesicles indicates that Cys acts on the cytoplasmic side of the enzyme. However, the Cys activation of truncated CopA lacking the N-terminal metal binding domain (N-MBD) indicates that activation by Cys is independent of the regulatory N-MBD. These results suggest that Cys is a non-essential activator of CopA, interacting with the cytoplasmic side of the enzyme while this is in an E1 form. Interestingly, these effects also point out that Cu(+) can reach the cytoplasmic opening of the access path into the transmembrane transport sites either as a free metal or a Cu(+)-Cys complex.
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Affiliation(s)
- Ying Yang
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, 100 Institute Rd., Worcester, MA 01609, USA
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48
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Nadella SR, Grosell M, Wood CM. Mechanisms of dietary Cu uptake in freshwater rainbow trout: evidence for Na-assisted Cu transport and a specific metal carrier in the intestine. J Comp Physiol B 2007; 177:433-46. [PMID: 17279389 DOI: 10.1007/s00360-006-0142-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 12/18/2006] [Accepted: 12/20/2006] [Indexed: 11/26/2022]
Abstract
Copper (Cu) is both a vital nutrient and a potent toxicant. The objective of this study was to analyze the mechanistic nature of intestinal Cu transport in rainbow trout using radiolabeled Cu (64Cu) and an in vitro gut sac technique. Reduction of mucosal NaCl levels inhibited Cu transport while increase caused stimulation; Na(2)SO(4) had an identical effect, implicating Na(+) rather than the anion. These responses were unrelated to solvent drag, osmotic pressure or changes in transepithelial potential. The presence of elevated luminal Ag stimulated Cu and Na(+) uptake. Phenamil caused a partial inhibition of both Cu and Na(+) uptake while hypercapnia stimulated Na(+) and Cu transport. Cu uptake was sensitive to luminal pH and inhibited by a tenfold excess of Fe and Zn. These factors had no effect on Na(+ )uptake. On the basis of these results we propose a novel Na(+)-assisted mechanism of Cu uptake wherein the Na(+) gradient stimulates an increase in the H(+) concentration of the brushborder creating a suitable microenvironment for the effective transport of Cu via either DMT1 or Ctr1.
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Affiliation(s)
- Sunita Rao Nadella
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON L8S4K1.
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Cater M, La fontaine S, Mercer J. Copper binding to the N-terminal metal-binding sites or the CPC motif is not essential for copper-induced trafficking of the human Wilson protein (ATP7B). Biochem J 2007; 401:143-53. [PMID: 16939419 PMCID: PMC1698686 DOI: 10.1042/bj20061055] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The Wilson protein (ATP7B) is a copper-translocating P-type ATPase that mediates the excretion of excess copper from hepatocytes into bile. Excess copper causes the protein to traffic from the TGN (trans-Golgi network) to subapical vesicles. Using site-directed mutagenesis, mutations known or predicted to abrogate catalytic activity (copper translocation) were introduced into ATP7B and the effect of these mutations on the intracellular trafficking of the protein was investigated. Mutation of the critical aspartic acid residue in the phosphorylation domain (DKTGTIT) blocked copper-induced redistribution of ATP7B from the TGN, whereas mutation of the phosphatase domain [TGE (Thr-Gly-Glu)] trapped ATP7B at cytosolic vesicular compartments. Our findings demonstrate that ATP7B trafficking is regulated with its copper-translocation cycle, with cytosolic vesicular localization associated with the acyl-phosphate intermediate. In addition, mutation of the six N-terminal metal-binding sites and/or the trans-membrane CPC (Cys-Pro-Cys) motif did not suppress the constitutive vesicular localization of the ATP7B phosphatase domain mutant. These results suggested that copper co-ordination by these sites is not essential for trafficking. Importantly, copper-chelation studies with these mutants clearly demonstrated a requirement for copper in ATP7B trafficking, suggesting the presence of an additional copper-binding site(s) within the protein. The results presented in this report significantly advance our understanding of the regulatory mechanism that links copper-translocation activity with copper-induced intracellular trafficking of ATP7B, which is central to hepatic and hence systemic copper homoeostasis.
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Affiliation(s)
- Michael A. Cater
- Centre for Cellular and Molecular Biology, School of Biological and Chemical Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia
| | - Sharon La fontaine
- Centre for Cellular and Molecular Biology, School of Biological and Chemical Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia
| | - Julian F. B. Mercer
- Centre for Cellular and Molecular Biology, School of Biological and Chemical Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia
- To whom correspondence should be addressed (email )
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50
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Hung Y, Layton M, Voskoboinik I, Mercer J, Camakaris J. Purification and membrane reconstitution of catalytically active Menkes copper-transporting P-type ATPase (MNK; ATP7A). Biochem J 2007; 401:569-79. [PMID: 17009961 PMCID: PMC1820817 DOI: 10.1042/bj20060924] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The MNK (Menkes disease protein; ATP7A) is a major copper- transporting P-type ATPase involved in the delivery of copper to cuproenzymes in the secretory pathway and the efflux of excess copper from extrahepatic tissues. Mutations in the MNK (ATP7A) gene result in Menkes disease, a fatal neurodegenerative copper deficiency disorder. Currently, detailed biochemical and biophysical analyses of MNK to better understand its mechanisms of copper transport are not possible due to the lack of purified MNK in an active form. To address this issue, we expressed human MNK with an N-terminal Glu-Glu tag in Sf9 [Spodoptera frugiperda (fall armyworm) 9] insect cells and purified it by antibody affinity chromatography followed by size-exclusion chromatography in the presence of the non-ionic detergent DDM (n-dodecyl beta-D-maltopyranoside). Formation of the classical vanadate-sensitive phosphoenzyme by purified MNK was activated by Cu(I) [EC50=0.7 microM; h (Hill coefficient) was 4.6]. Furthermore, we report the first measurement of Cu(I)-dependent ATPase activity of MNK (K0.5=0.6 microM; h=5.0). The purified MNK demonstrated active ATP-dependent vectorial 64Cu transport when reconstituted into soya-bean asolectin liposomes. Together, these data demonstrated that Cu(I) interacts with MNK in a co-operative manner and with high affinity in the sub-micromolar range. The present study provides the first biochemical characterization of a purified full-length mammalian copper-transporting P-type ATPase associated with a human disease.
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Affiliation(s)
- Ya Hui Hung
- *Department of Genetics, University of Melbourne, VIC 3010, Australia
| | - Meredith J. Layton
- †Joint Proteomics Laboratory, Ludwig Institute for Cancer Research and Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3050, Australia
| | - Ilia Voskoboinik
- *Department of Genetics, University of Melbourne, VIC 3010, Australia
| | - Julian F. B. Mercer
- ‡Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, VIC 3125, Australia
| | - James Camakaris
- *Department of Genetics, University of Melbourne, VIC 3010, Australia
- To whom correspondence should be addressed (email )
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