1
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Orädd F, Steffen JH, Gourdon P, Andersson M. Copper binding leads to increased dynamics in the regulatory N-terminal domain of full-length human copper transporter ATP7B. PLoS Comput Biol 2022; 18:e1010074. [PMID: 36070320 PMCID: PMC9484656 DOI: 10.1371/journal.pcbi.1010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 09/19/2022] [Accepted: 08/17/2022] [Indexed: 11/25/2022] Open
Abstract
ATP7B is a human copper-transporting P1B-type ATPase that is involved in copper homeostasis and resistance to platinum drugs in cancer cells. ATP7B consists of a copper-transporting core and a regulatory N-terminal tail that contains six metal-binding domains (MBD1-6) connected by linker regions. The MBDs can bind copper, which changes the dynamics of the regulatory domain and activates the protein, but the underlying mechanism remains unknown. To identify possible copper-specific structural dynamics involved in transport regulation, we constructed a model of ATP7B spanning the N-terminal tail and core catalytic domains and performed molecular dynamics (MD) simulations with (holo) and without (apo) copper ions bound to the MBDs. In the holo protein, MBD2, MBD3 and MBD5 showed enhanced mobilities, which resulted in a more extended N-terminal regulatory region. The observed separation of MBD2 and MBD3 from the core protein supports a mechanism where copper binding activates the ATP7B protein by reducing interactions among MBD1-3 and between MBD1-3 and the core protein. We also observed an increased interaction between MBD5 and the core protein that brought the copper-binding site of MBD5 closer to the high-affinity internal copper-binding site in the core protein. The simulation results assign specific, mechanistic roles to the metal-binding domains involved in ATP7B regulation that are testable in experimental settings. Living organisms depend upon active transport against gradients across biological membranes for survival. Such transport can be accomplished by ATP-dependent membrane protein transporters for which the activity must be regulated to maintain optimal concentrations in the cellular compartments. The regulatory mechanisms often involve structural responses inherent to the protein structure, which because of their dynamic nature can be hard to assess experimentally. A prime example is regulation of cellular copper levels by a copper-binding tail in the human copper transporter ATP7B. Dysregulation can cause severe diseases, for example the copper metabolism disorder Wilson’s disease, which is caused by mutations in ATP7B regulation machinery. Due to the practical difficulties in working with membrane proteins, most studies of ATP7B have been conducted in the absence of the membrane-bound protein core. Here, we used computer simulations of full-length ATP7B to study how structural dynamics in the regulatory tail differ between copper-bound and copper-free states. Copper induced increased dynamics in the tail, resulting in an overall movement towards the ion-binding site in the protein core. The simulations identified several, hitherto not reported, interactions between the regulatory tail and the protein core that can be targeted experimentally to enhance our understanding of this medically relevant regulatory mechanism.
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Affiliation(s)
- Fredrik Orädd
- Department of Chemistry, Umeå University, Umeå, Sweden
| | - Jonas Hyld Steffen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Pontus Gourdon
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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2
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Andrei A, Di Renzo MA, Öztürk Y, Meisner A, Daum N, Frank F, Rauch J, Daldal F, Andrade SLA, Koch HG. The CopA2-Type P 1B-Type ATPase CcoI Serves as Central Hub for cbb 3-Type Cytochrome Oxidase Biogenesis. Front Microbiol 2021; 12:712465. [PMID: 34589071 PMCID: PMC8475189 DOI: 10.3389/fmicb.2021.712465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 07/12/2021] [Indexed: 11/13/2022] Open
Abstract
Copper (Cu)-transporting P1B-type ATPases are ubiquitous metal transporters and crucial for maintaining Cu homeostasis in all domains of life. In bacteria, the P1B-type ATPase CopA is required for Cu-detoxification and exports excess Cu(I) in an ATP-dependent reaction from the cytosol into the periplasm. CopA is a member of the CopA1-type ATPase family and has been biochemically and structurally characterized in detail. In contrast, less is known about members of the CopA2-type ATPase family, which are predicted to transport Cu(I) into the periplasm for cuproprotein maturation. One example is CcoI, which is required for the maturation of cbb 3-type cytochrome oxidase (cbb 3-Cox) in different species. Here, we reconstituted purified CcoI of Rhodobacter capsulatus into liposomes and determined Cu transport using solid-supported membrane electrophysiology. The data demonstrate ATP-dependent Cu(I) translocation by CcoI, while no transport is observed in the presence of a non-hydrolysable ATP analog. CcoI contains two cytosolically exposed N-terminal metal binding sites (N-MBSs), which are both important, but not essential for Cu delivery to cbb 3-Cox. CcoI and cbb 3-Cox activity assays in the presence of different Cu concentrations suggest that the glutaredoxin-like N-MBS1 is primarily involved in regulating the ATPase activity of CcoI, while the CopZ-like N-MBS2 is involved in Cu(I) acquisition. The interaction of CcoI with periplasmic Cu chaperones was analyzed by genetically fusing CcoI to the chaperone SenC. The CcoI-SenC fusion protein was fully functional in vivo and sufficient to provide Cu for cbb 3-Cox maturation. In summary, our data demonstrate that CcoI provides the link between the cytosolic and periplasmic Cu chaperone networks during cbb 3-Cox assembly.
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Affiliation(s)
- Andreea Andrei
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.,Faculty of Biology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Maria Agostina Di Renzo
- Institute for Biochemistry, Faculty of Chemistry and Pharmacy, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany.,Faculty of Chemistry and Pharmacy, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Yavuz Öztürk
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Alexandra Meisner
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Noel Daum
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Fabian Frank
- Institute for Biochemistry, Faculty of Chemistry and Pharmacy, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Juna Rauch
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Fevzi Daldal
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
| | - Susana L A Andrade
- Institute for Biochemistry, Faculty of Chemistry and Pharmacy, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Hans-Georg Koch
- Institut für Biochemie und Molekularbiologie, ZBMZ, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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3
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Abstract
Copper is a redox-active transition metal ion required for the function of many essential human proteins. For biosynthesis of proteins coordinating copper, the metal may bind before, during or after folding of the polypeptide. If the metal binds to unfolded or partially folded structures of the protein, such coordination may modulate the folding reaction. The molecular understanding of how copper is incorporated into proteins requires descriptions of chemical, thermodynamic, kinetic and structural parameters involved in the formation of protein-metal complexes. Because free copper ions are toxic, living systems have elaborate copper-transport systems that include particular proteins that facilitate efficient and specific delivery of copper ions to target proteins. Therefore, these pathways become an integral part of copper protein folding in vivo. This review summarizes biophysical-molecular in vitro work assessing the role of copper in folding and stability of copper-binding proteins as well as protein-protein copper exchange reactions between human copper transport proteins. We also describe some recent findings about the participation of copper ions and copper proteins in protein misfolding and aggregation reactions in vitro.
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4
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Subedi P, Paxman JJ, Wang G, Ukuwela AA, Xiao Z, Heras B. The Scs disulfide reductase system cooperates with the metallochaperone CueP in Salmonella copper resistance. J Biol Chem 2019; 294:15876-15888. [PMID: 31444272 DOI: 10.1074/jbc.ra119.010164] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 08/21/2019] [Indexed: 12/31/2022] Open
Abstract
The human pathogen Salmonella enterica serovar Typhimurium (S Typhimurium) contains a complex disulfide bond (Dsb) catalytic machinery. This machinery encompasses multiple Dsb thiol-disulfide oxidoreductases that mediate oxidative protein folding and a less-characterized suppressor of copper sensitivity (scs) gene cluster, associated with increased tolerance to copper. To better understand the function of the Salmonella Scs system, here we characterized two of its key components, the membrane protein ScsB and the periplasmic protein ScsC. Our results revealed that these two proteins form a redox pair in which the electron transfer from the periplasmic domain of ScsB (n-ScsB) to ScsC is thermodynamically driven. We also demonstrate that the Scs reducing pathway remains separate from the Dsb oxidizing pathways and thereby avoids futile redox cycles. Additionally, we provide new insight into the molecular mechanism underlying Scs-mediated copper tolerance in Salmonella We show that both ScsB and ScsC can bind toxic copper(I) with femtomolar affinities and transfer it to the periplasmic copper metallochaperone CueP. Our results indicate that the Salmonella Scs machinery has evolved a dual mode of action, capable of transferring reducing power to the oxidizing periplasm and protecting against copper stress by cooperating with the cue regulon, a major copper resistance mechanism in Salmonella. Overall, these findings expand our understanding of the functional diversity of Dsb-like systems, ranging from those mediating oxidative folding of proteins required for infection to those contributing to defense mechanisms against oxidative stress and copper toxicity, critical traits for niche adaptation and survival.
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Affiliation(s)
- Pramod Subedi
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Kingsbury Drive, Bundoora, Victoria 3083, Australia
| | - Jason J Paxman
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Kingsbury Drive, Bundoora, Victoria 3083, Australia
| | - Geqing Wang
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Kingsbury Drive, Bundoora, Victoria 3083, Australia
| | - Ashwinie A Ukuwela
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Zhiguang Xiao
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia.,Melbourne Dementia Research Centre, Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Begoña Heras
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Kingsbury Drive, Bundoora, Victoria 3083, Australia
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5
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Zhou L, Kay KL, Hecht O, Moore GR, Le Brun NE. The N-terminal domains of Bacillus subtilis CopA do not form a stable complex in the absence of their inter-domain linker. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:275-282. [DOI: 10.1016/j.bbapap.2017.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/02/2017] [Accepted: 11/12/2017] [Indexed: 10/18/2022]
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6
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Ariöz C, Li Y, Wittung-Stafshede P. The six metal binding domains in human copper transporter, ATP7B: molecular biophysics and disease-causing mutations. Biometals 2017; 30:823-840. [PMID: 29063292 PMCID: PMC5684295 DOI: 10.1007/s10534-017-0058-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 10/05/2017] [Indexed: 12/16/2022]
Abstract
Wilson Disease (WD) is a hereditary genetic disorder, which coincides with a dysfunctional copper (Cu) metabolism caused by mutations in ATP7B, a membrane-bound P1B-type ATPase responsible for Cu export from hepatic cells. The N-terminal part (~ 600 residues) of the multi-domain 1400-residue ATP7B constitutes six metal binding domains (MBDs), each of which can bind a copper ion, interact with other ATP7B domains as well as with different proteins. Although the ATP7B's MBDs have been investigated in vitro and in vivo intensively, it remains unclear how these domains modulate overall structure, dynamics, stability and function of ATP7B. The presence of six MBDs is unique to mammalian ATP7B homologs, and many WD causing missense mutations are found in these domains. Here, we have summarized previously reported in vitro biophysical data on the MBDs of ATP7B and WD point mutations located in these domains. Besides the demonstration of where the research field stands today, this review showcasts the need for further biophysical investigation about the roles of MBDs in ATP7B function. Molecular mechanisms of ATP7B are important not only in the development of new WD treatment but also for other aspects of human physiology where Cu transport plays a role.
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Affiliation(s)
- Candan Ariöz
- Department of Biology and Biological Engineering, Division of Chemical Biology, Chalmers University of Technology, Kemigården 4, 412 96 Gothenburg, Sweden
| | - Yaozong Li
- Department of Chemistry, Umeå University, Kemihuset A, Linnaeus väg 10, 901 87 Umeå, Sweden
| | - Pernilla Wittung-Stafshede
- Department of Biology and Biological Engineering, Division of Chemical Biology, Chalmers University of Technology, Kemigården 4, 412 96 Gothenburg, Sweden
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7
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Yu CH, Yang N, Bothe J, Tonelli M, Nokhrin S, Dolgova NV, Braiterman L, Lutsenko S, Dmitriev OY. The metal chaperone Atox1 regulates the activity of the human copper transporter ATP7B by modulating domain dynamics. J Biol Chem 2017; 292:18169-18177. [PMID: 28900031 DOI: 10.1074/jbc.m117.811752] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 09/01/2017] [Indexed: 01/28/2023] Open
Abstract
The human transporter ATP7B delivers copper to the biosynthetic pathways and maintains copper homeostasis in the liver. Mutations in ATP7B cause the potentially fatal hepatoneurological disorder Wilson disease. The activity and intracellular localization of ATP7B are regulated by copper, but the molecular mechanism of this regulation is largely unknown. We show that the copper chaperone Atox1, which delivers copper to ATP7B, and the group of the first three metal-binding domains (MBD1-3) are central to the activity regulation of ATP7B. Atox1-Cu binding to ATP7B changes domain dynamics and interactions within the MBD1-3 group and activates ATP hydrolysis. To understand the mechanism linking Atox1-MBD interactions and enzyme activity, we have determined the MBD1-3 conformational space using small angle X-ray scattering and identified changes in MBD dynamics caused by apo-Atox1 and Atox1-Cu by solution NMR. The results show that copper transfer from Atox1 decreases domain interactions within the MBD1-3 group and increases the mobility of the individual domains. The N-terminal segment of MBD1-3 was found to interact with the nucleotide-binding domain of ATP7B, thus physically coupling the domains involved in copper binding and those involved in ATP hydrolysis. Taken together, the data suggest a regulatory mechanism in which Atox1-mediated copper transfer activates ATP7B by releasing inhibitory constraints through increased freedom of MBD1-3 motions.
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Affiliation(s)
- Corey H Yu
- From the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Nan Yang
- the Department of Physiology, Johns Hopkins Medical University, Baltimore, Maryland 21205, and
| | - Jameson Bothe
- the National Magnetic Resonance Facility at Madison, University of Wisconsin, Madison, Wisconsin 53706
| | - Marco Tonelli
- the National Magnetic Resonance Facility at Madison, University of Wisconsin, Madison, Wisconsin 53706
| | - Sergiy Nokhrin
- From the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Natalia V Dolgova
- From the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Lelita Braiterman
- the Department of Physiology, Johns Hopkins Medical University, Baltimore, Maryland 21205, and
| | - Svetlana Lutsenko
- the Department of Physiology, Johns Hopkins Medical University, Baltimore, Maryland 21205, and
| | - Oleg Y Dmitriev
- From the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada,
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8
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Yu CH, Dolgova NV, Dmitriev OY. Dynamics of the metal binding domains and regulation of the human copper transporters ATP7B and ATP7A. IUBMB Life 2017; 69:226-235. [DOI: 10.1002/iub.1611] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 02/03/2017] [Indexed: 01/20/2023]
Affiliation(s)
- Corey H. Yu
- Department of Biochemistry; University of Saskatchewan; Saskatoon SK Canada
| | - Natalia V. Dolgova
- Department of Biochemistry; University of Saskatchewan; Saskatoon SK Canada
| | - Oleg Y. Dmitriev
- Department of Biochemistry; University of Saskatchewan; Saskatoon SK Canada
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9
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Argüello JM, Patel SJ, Quintana J. Bacterial Cu(+)-ATPases: models for molecular structure-function studies. Metallomics 2016; 8:906-14. [PMID: 27465346 PMCID: PMC5025381 DOI: 10.1039/c6mt00089d] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The early discovery of the human Cu(+)-ATPases and their link to Menkes and Wilson's diseases brought attention to the unique role of these transporters in copper homeostasis. The characterization of bacterial Cu(+)-ATPases has significantly furthered our understanding of the structure, selectivity and transport mechanism of these enzymes, as well as their interplay with other elements of Cu(+) distribution networks. This review focuses on the structural-functional insights that have emerged from studies of bacterial Cu(+)-ATPases at the molecular level and how these observations have contributed to drawing up a comprehensive picture of cellular copper homeostasis.
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Affiliation(s)
- José M Argüello
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA.
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10
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Abstract
Copper (Cu) is an essential transition metal providing activity to key enzymes in the human body. To regulate the levels and avoid toxicity, cells have developed elaborate systems for loading these enzymes with Cu. Most Cu-dependent enzymes obtain the metal from the membrane-bound Cu pumps ATP7A/B in the Golgi network. ATP7A/B receives Cu from the cytoplasmic Cu chaperone Atox1 that acts as the cytoplasmic shuttle between the cell membrane Cu importer, Ctr1 and ATP7A/B. Biological, genetic and structural efforts have provided a tremendous amount of information for how the proteins in this pathway work. Nonetheless, basic mechanistic-biophysical questions (such as how and where ATP7A/B receives Cu, how ATP7A/B conformational changes and domain-domain interactions facilitate Cu movement through the membrane, and, finally, how target polypeptides are loaded with Cu in the Golgi) remain elusive. In this perspective, unresolved inquiries regarding ATP7A/B mechanism will be highlighted. The answers are important from a fundamental view, since mechanistic aspects may be common to other metal transport systems, and for medical purposes, since many diseases appear related to Cu transport dysregulation.
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11
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Laurent C, Lekeux G, Ukuwela AA, Xiao Z, Charlier JB, Bosman B, Carnol M, Motte P, Damblon C, Galleni M, Hanikenne M. Metal binding to the N-terminal cytoplasmic domain of the PIB ATPase HMA4 is required for metal transport in Arabidopsis. PLANT MOLECULAR BIOLOGY 2016; 90:453-66. [PMID: 26797794 DOI: 10.1007/s11103-016-0429-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 01/03/2016] [Indexed: 05/26/2023]
Abstract
PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding domains, which may be involved in metal sensing, metal ion selectivity and/or in regulation of the pump activity. The PIB ATPase HMA4 (Heavy Metal ATPase 4) plays a central role in metal homeostasis in Arabidopsis thaliana and has a key function in zinc and cadmium hypertolerance and hyperaccumulation in the extremophile plant species Arabidopsis halleri. Here, we examined the function and structure of the N-terminal cytoplasmic metal-binding domain of HMA4. We mutagenized a conserved CCTSE metal-binding motif in the domain and assessed the impact of the mutations on protein function and localization in planta, on metal-binding properties in vitro and on protein structure by Nuclear Magnetic Resonance spectroscopy. The two Cys residues of the motif are essential for the function, but not for localization, of HMA4 in planta, whereas the Glu residue is important but not essential. These residues also determine zinc coordination and affinity. Zinc binding to the N-terminal domain is thus crucial for HMA4 protein function, whereas it is not required to maintain the protein structure. Altogether, combining in vivo and in vitro approaches in our study provides insights towards the molecular understanding of metal transport and specificity of metal P-type ATPases.
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Affiliation(s)
- Clémentine Laurent
- Department of Life Sciences, Center for Protein Engineering (CIP), University of Liège, 4000, Liège, Belgium
| | - Gilles Lekeux
- Department of Life Sciences, Center for Protein Engineering (CIP), University of Liège, 4000, Liège, Belgium
| | - Ashwinie A Ukuwela
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Zhiguang Xiao
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Jean-Benoit Charlier
- Department of Life Sciences, Center for Protein Engineering (CIP), University of Liège, 4000, Liège, Belgium
| | - Bernard Bosman
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, 4000, Liège, Belgium
| | - Monique Carnol
- Laboratory of Plant and Microbial Ecology, Department of Biology, Ecology, Evolution, University of Liège, 4000, Liège, Belgium
| | - Patrick Motte
- Department of Life Sciences, Center for Protein Engineering (CIP), University of Liège, 4000, Liège, Belgium
- PhytoSYSTEMS, University of Liège, 4000, Liège, Belgium
| | - Christian Damblon
- Chimie Biologique Structurale, Department of Chemistry, University of Liège, Liège, Belgium
| | - Moreno Galleni
- Department of Life Sciences, Center for Protein Engineering (CIP), University of Liège, 4000, Liège, Belgium
| | - Marc Hanikenne
- Department of Life Sciences, Center for Protein Engineering (CIP), University of Liège, 4000, Liège, Belgium.
- PhytoSYSTEMS, University of Liège, 4000, Liège, Belgium.
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12
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Mondol T, Åden J, Wittung-Stafshede P. Copper binding triggers compaction in N-terminal tail of human copper pump ATP7B. Biochem Biophys Res Commun 2016; 470:663-669. [DOI: 10.1016/j.bbrc.2016.01.085] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 01/14/2016] [Indexed: 02/01/2023]
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13
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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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14
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Niemiec MS, Dingeldein APG, Wittung-Stafshede P. Enthalpy-entropy compensation at play in human copper ion transfer. Sci Rep 2015; 5:10518. [PMID: 26013029 PMCID: PMC4444973 DOI: 10.1038/srep10518] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 04/16/2015] [Indexed: 11/09/2022] Open
Abstract
Copper (Cu) is an essential trace element but toxic in free form. After cell uptake, Cu is transferred, via direct protein-protein interactions, from the chaperone Atox1 to the Wilson disease protein (WD) for incorporation into Cu-dependent enzymes. Cu binds to a conserved C(1)XXC(2) motif in the chaperone as well as in each of the cytoplasmic metal-binding domains of WD. Here, we dissect mechanism and thermodynamics of Cu transfer from Atox1 to the fourth metal binding domain of WD. Using chromatography and calorimetry together with single Cys-to-Ala variants, we demonstrate that Cu-dependent protein heterocomplexes require the presence of C(1) but not C(2). Comparison of thermodynamic parameters for mutant versus wild type reactions reveals that the wild type reaction involves strong entropy-enthalpy compensation. This property is explained by a dynamic inter-conversion of Cu-Cys coordinations in the wild type ensemble and may provide functional advantage by protecting against Cu mis-ligation and bypassing enthalpic traps.
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15
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Drees SL, Beyer DF, Lenders-Lomscher C, Lübben M. Distinct functions of serial metal-binding domains in the Escherichia coli P1 B -ATPase CopA. Mol Microbiol 2015; 97:423-38. [PMID: 25899340 DOI: 10.1111/mmi.13038] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2015] [Indexed: 12/17/2022]
Abstract
P1 B -ATPases are among the most common resistance factors to metal-induced stress. Belonging to the superfamily of P-type ATPases, they are capable of exporting transition metal ions at the expense of adenosine triphosphate (ATP) hydrolysis. P1 B -ATPases share a conserved structure of three cytoplasmic domains linked by a transmembrane domain. In addition, they possess a unique class of domains located at the N-terminus. In bacteria, these domains are primarily associated with metal binding and either occur individually or as serial copies of each other. Within this study, the roles of the two adjacent metal-binding domains (MBDs) of CopA, the copper export ATPase of Escherichia coli were investigated. From biochemical and physiological data, we deciphered the protein-internal pathway of copper and demonstrate the distal N-terminal MBD to possess a function analogous to the metallochaperones of related prokaryotic copper resistance systems, that is its involvement in the copper transfer to the membrane-integral ion-binding sites of CopA. In contrast, the proximal domain MBD2 has a regulatory role by suppressing the catalytic activity of CopA in absence of copper. Furthermore, we propose a general functional divergence of tandem MBDs in P1 B -ATPases, which is governed by the length of the inter-domain linker.
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Affiliation(s)
- Steffen L Drees
- Department of Biophysics, Ruhr University Bochum, Universitätsstr. 150, D-44801, Bochum, Germany
| | - Dominik F Beyer
- Department of Biophysics, Ruhr University Bochum, Universitätsstr. 150, D-44801, Bochum, Germany
| | | | - Mathias Lübben
- Department of Biophysics, Ruhr University Bochum, Universitätsstr. 150, D-44801, Bochum, Germany
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16
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Wu F, Wang J, Pu C, Qiao L, Jiang C. Wilson's disease: a comprehensive review of the molecular mechanisms. Int J Mol Sci 2015; 16:6419-31. [PMID: 25803104 PMCID: PMC4394540 DOI: 10.3390/ijms16036419] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 03/03/2015] [Accepted: 03/03/2015] [Indexed: 02/06/2023] Open
Abstract
Wilson’s disease (WD), also known as hepatolenticular degeneration, is an autosomal recessive inherited disorder resulting from abnormal copper metabolism. Reduced copper excretion causes an excessive deposition of the copper in many organs such as the liver, central nervous system (CNS), cornea, kidney, joints, and cardiac muscle where the physiological functions of the affected organs are impaired. The underlying molecular mechanisms for WD have been extensively studied. It is now believed that a defect in P-type adenosine triphosphatase (ATP7B), the gene encoding the copper transporting P-type ATPase, is responsible for hepatic copper accumulation. Deposited copper in the liver produces toxic effects via modulating several molecular pathways. WD can be a lethal disease if left untreated. A better understanding of the molecular mechanisms causing the aberrant copper deposition and organ damage is the key to developing effective management approaches.
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Affiliation(s)
- Fei Wu
- Department of imaging, the Affiliated Zhongshan Hospital of Dalian University, 6 Jiefang Street, Zhongshan District, Dalian 116001, Liaoning, China.
| | - Jing Wang
- Department of Internal Medicine, the Second Hospital of Dalian Medical University, 467 Zhongshan Road, Shahekou District, Dalian 116023, Liaoning, China.
| | - Chunwen Pu
- Department of Biobank, the Sixth People's Hospital of Dalian, 269 Luganghuibai Road, Ganjingzi District, Dalian 116031, Liaoning, China.
| | - Liang Qiao
- Storr Liver Centre, Westmead Millennium Institute for Medical Research, Faculty of Medicine, the University of Sydney at Westmead Hospital, Westmead, NSW 2145, Australia.
| | - Chunmeng Jiang
- Department of Internal Medicine, the Second Hospital of Dalian Medical University, 467 Zhongshan Road, Shahekou District, Dalian 116023, Liaoning, China.
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17
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Braiterman LT, Gupta A, Chaerkady R, Cole RN, Hubbard AL. Communication between the N and C termini is required for copper-stimulated Ser/Thr phosphorylation of Cu(I)-ATPase (ATP7B). J Biol Chem 2015; 290:8803-19. [PMID: 25666620 DOI: 10.1074/jbc.m114.627414] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Indexed: 11/06/2022] Open
Abstract
The Wilson disease protein ATP7B exhibits copper-dependent trafficking. In high copper, ATP7B exits the trans-Golgi network and moves to the apical domain of hepatocytes where it facilitates elimination of excess copper through the bile. Copper levels also affect ATP7B phosphorylation. ATP7B is basally phosphorylated in low copper and becomes more phosphorylated ("hyperphosphorylated") in elevated copper. The functional significance of hyperphosphorylation remains unclear. We showed that hyperphosphorylation occurs even when ATP7B is restricted to the trans-Golgi network. We performed comprehensive phosphoproteomics of ATP7B in low versus high copper, which revealed that 24 Ser/Thr residues in ATP7B could be phosphorylated, and only four of these were copper-responsive. Most of the phosphorylated sites were found in the N- and C-terminal cytoplasmic domains. Using truncation and mutagenesis, we showed that inactivation or elimination of all six N-terminal metal binding domains did not block copper-dependent, reversible, apical trafficking but did block hyperphosphorylation in hepatic cells. We showed that nine of 15 Ser/Thr residues in the C-terminal domain were phosphorylated. Inactivation of 13 C-terminal phosphorylation sites reduced basal phosphorylation and eliminated hyperphosphorylation, suggesting that copper binding at the N terminus propagates to the ATP7B C-terminal region. C-terminal mutants with either inactivating or phosphomimetic substitutions showed little effect upon copper-stimulated trafficking, indicating that trafficking does not depend on phosphorylation at these sites. Thus, our studies revealed that copper-dependent conformational changes in the N-terminal region lead to hyperphosphorylation at C-terminal sites, which seem not to affect trafficking and may instead fine-tune copper sequestration.
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Affiliation(s)
| | | | - Raghothama Chaerkady
- the Mass Spectrometry and Proteomics Facility, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Robert N Cole
- the Mass Spectrometry and Proteomics Facility, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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18
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Møller LB. Small amounts of functional ATP7A protein permit mild phenotype. J Trace Elem Med Biol 2015; 31:173-7. [PMID: 25172213 DOI: 10.1016/j.jtemb.2014.07.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 06/11/2014] [Accepted: 07/03/2014] [Indexed: 11/15/2022]
Abstract
Mutations in ATP7A lead to at least three allelic disorders: Menkes disease (MD), Occipital horn syndrome and X-linked distal motor neuropathy. These disorders are mainly seen in male individuals, but a few affected females have been described. More than 400 different mutations have been identified in the ATP7A gene. We have conducted several studies in the hope of uncovering the relationship between genotype and phenotype. We have examined the X-inactivation pattern in affected females, the effect of exon-deletions and--duplications, and splice-site mutations on the composition and amount of ATP7A transcript, and we have examined the structural location of missense mutations. The X-inactivation pattern did not fully explain the manifestation of MD in a small fraction of carriers. Most of the affected females had preferential inactivation of the X-chromosome with the normal ATP7A gene, but a few individuals exhibited preferential inactivation of the X-chromosome with the mutated ATP7A gene. The observed mild phenotype in some patients with mutations that effect the composition of the ATP7A transcript, seems to be explained by the presence of a small amount of normal ATP7A transcript. The location of missense mutations on structural models of the ATP7A protein suggests that affected conserved residues generally lead to a severe phenotype. The ATP7A protein traffics within the cells. At low copper levels, ATP7A locates to the Trans-Golgi Network (TGN) to load cuproenzymes with copper, whereas at higher concentrations, ATP7A shifts to the post-Golgi compartments or to the plasma membrane to export copper out of the cell. Impaired copper-regulation trafficking has been observed for ATP7A mutants, but its impact on the clinical outcome is not clear. The major problem in patients with MD seems to be insufficient amounts of copper in the brain. In fact, prenatal treatment of mottled mice as a model for human MD with a combination of chelator and copper, produces a slight increase in copper levels in the brain which perhaps leads to longer survival and more active behavior. In conclusion, small amounts of copper at the right location seem to relieve the symptoms.
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Affiliation(s)
- Lisbeth Birk Møller
- Center for Applied Human Genetics, Kennedy Center, Rigshospitalet, Gl. Landevej 7, 2600 Glostrup, Denmark.
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19
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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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20
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Distinct phenotype of a Wilson disease mutation reveals a novel trafficking determinant in the copper transporter ATP7B. Proc Natl Acad Sci U S A 2014; 111:E1364-73. [PMID: 24706876 DOI: 10.1073/pnas.1314161111] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Wilson disease (WD) is a monogenic autosomal-recessive disorder of copper accumulation that leads to liver failure and/or neurological deficits. WD is caused by mutations in ATP7B, a transporter that loads Cu(I) onto newly synthesized cupro-enzymes in the trans-Golgi network (TGN) and exports excess copper out of cells by trafficking from the TGN to the plasma membrane. To date, most WD mutations have been shown to disrupt ATP7B activity and/or stability. Using a multidisciplinary approach, including clinical analysis of patients, cell-based assays, and computational studies, we characterized a patient mutation, ATP7B(S653Y), which is stable, does not disrupt Cu(I) transport, yet renders the protein unable to exit the TGN. Bulky or charged substitutions at position 653 mimic the phenotype of the patient mutation. Molecular modeling and dynamic simulation suggest that the S653Y mutation induces local distortions within the transmembrane (TM) domain 1 and alter TM1 interaction with TM2. S653Y abolishes the trafficking-stimulating effects of a secondary mutation in the N-terminal apical targeting domain. This result indicates a role for TM1/TM2 in regulating conformations of cytosolic domains involved in ATP7B trafficking. Taken together, our experiments revealed an unexpected role for TM1/TM2 in copper-regulated trafficking of ATP7B and defined a unique class of WD mutants that are transport-competent but trafficking-defective. Understanding the precise consequences of WD-causing mutations will facilitate the development of advanced mutation-specific therapies.
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21
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Zhitnitsky D, Lewinson O. Identification of functionally important conserved trans-membrane residues of bacterial PIB -type ATPases. Mol Microbiol 2014; 91:777-89. [PMID: 24350798 PMCID: PMC4285229 DOI: 10.1111/mmi.12495] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2013] [Indexed: 01/23/2023]
Abstract
Powered by ATP hydrolysis, PIB-ATPases drive the energetically uphill transport of transition metals. These high affinity pumps are essential for heavy metal detoxification and delivery of metal cofactors to specific cellular compartments. Amino acid sequence alignment of the trans-membrane (TM) helices of PIB-ATPases reveals a high degree of conservation, with ∼60–70 fully conserved positions. Of these conserved positions, 6–7 were previously identified to be important for transport. However, the functional importance of the majority of the conserved TM residues remains unclear. To investigate the role of conserved TM residues of PIB-ATPases we conducted an extensive mutagenesis study of a Zn2+ Cd2+ PIB-ATPase from Rhizobium radiobacter (rrZntA) and seven other PIB-ATPases. Of the 38 conserved positions tested, 24 had small effects on metal tolerance. Fourteen mutations compromised in vivo metal tolerance and in vitro metal-stimulated ATPase activity. Based on structural modelling, the functionally important residues line a constricted ‘channel’, tightly surrounded by the residues that were found to be inconsequential for function. We tentatively propose that the distribution of the mutable and immutable residues marks a possible trans-membrane metal translocation pathway. In addition, by substituting six trans-membrane amino acids of rrZntA we changed the in vivo metal specificity of this pump from Zn2+ Cd2+ to Ag+.
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Affiliation(s)
- Daniel Zhitnitsky
- Department of Microbiology, The Bruce and Ruth Rappaport Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel
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22
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In silico investigation of the ATP7B gene: insights from functional prediction of non-synonymous substitution to protein structure. Biometals 2013; 27:53-64. [PMID: 24253677 DOI: 10.1007/s10534-013-9686-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 11/07/2013] [Indexed: 01/22/2023]
Abstract
ATP7B is a copper-transporting ATPase that plays a key role in the regulation of copper homeostasis. Mutations in the ATP7B gene are causative for Wilson's disease, and recent reports have suggested that genetic variants are associated with susceptibility to Alzheimer's disease. Unfortunately, it is difficult to profile experimentally novel genetic variants in the ATP7B gene, because the human protein X-ray structure is not yet entirely understood. In order to investigate ATP7B non-synonymous substitutions, we used an in silico amino acid sequence-based approach. Specifically, we analyzed 337 ATP7B non-synonymous substitutions, which included Wilson's disease-causing mutations (DVs) and non Wilson's disease-causing variants (NDVs), with an algorithm that estimated a combined probability (cPdel) of an amino acidic change to be deleterious for the protein function. This approach appeared to reliably indentify the probability of DVs and NDVs to be deleterious and to profile still unknown gene variants. Specifically, after analyzing ATP7B protein domains with the cPdel method, we found results in line with the predicted-modeled domains and some new suggestions. In conclusion, a functional survey of amino acid changes in the ATP7B protein is provided herein, and we suggest that this bioinformatic method can furnish information about novel ATP7B mutations. Furthermore, the same approach can be applied to other uncharacterized proteins.
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23
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Chen P, Keller AM, Joshi CP, Martell DJ, Andoy NM, Benítez JJ, Chen TY, Santiago AG, Yang F. Single-molecule dynamics and mechanisms of metalloregulators and metallochaperones. Biochemistry 2013; 52:7170-83. [PMID: 24053279 DOI: 10.1021/bi400597v] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Understanding how cells regulate and transport metal ions is an important goal in the field of bioinorganic chemistry, a frontier research area that resides at the interface of chemistry and biology. This Current Topic reviews recent advances from the authors' group in using single-molecule fluorescence imaging techniques to identify the mechanisms of metal homeostatic proteins, including metalloregulators and metallochaperones. It emphasizes the novel mechanistic insights into how dynamic protein-DNA and protein-protein interactions offer efficient pathways via which MerR-family metalloregulators and copper chaperones can fulfill their functions. This work also summarizes other related single-molecule studies of bioinorganic systems and provides an outlook toward single-molecule imaging of metalloprotein functions in living cells.
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Affiliation(s)
- Peng Chen
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
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24
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Zielazinski EL, González-Guerrero M, Subramanian P, Stemmler TL, Argüello JM, Rosenzweig AC. Sinorhizobium meliloti Nia is a P(1B-5)-ATPase expressed in the nodule during plant symbiosis and is involved in Ni and Fe transport. Metallomics 2013; 5:1614-1623. [PMID: 24056637 DOI: 10.1039/c3mt00195d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The P1B-ATPases are a ubiquitous family of metal transporters. These transporters are classified into subfamilies on the basis of substrate specificity, which is conferred by conserved amino acids in the last three transmembrane domains. Five subfamilies have been identified to date, and representative members of four (P1B-1 to P1B-4) have been studied. The fifth family (P1B-5), of which some members contain a C-terminal hemerythrin (Hr) domain, is less well characterized. The S. meliloti Sma1163 gene encodes for a P1B-5-ATPase, denoted Nia (Nickel-iron ATPase), that is induced by exogenous Fe(2+) and Ni(2+). The nia mutant accumulates nickel and iron, suggesting a possible role in detoxification of these two elements under free-living conditions, as well as in symbiosis, when the highest expression levels are measured. This function is supported by an inhibitory effect of Fe(2+) and Ni(2+) on the pNPPase activity, and by the ability of Nia to bind Fe(2+) in the transmembrane domain. Optical and X-ray absorption spectroscopic studies of the isolated Hr domain confirm the presence of a dinuclear iron center and suggest that this domain might function as an iron sensor.
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Affiliation(s)
- Eliza L Zielazinski
- Departments of Molecular Biosciences and of Chemistry. Northwestern University, Evanston, Illinois, USA.
| | - Manuel González-Guerrero
- Centro de Biotecnología y Genómica de Plantas (CBGP), Universidad Politécnica de Madrid, Campus de Montegancedo, Pozuelo de Alarcón, Madrid, Spain
| | - Poorna Subramanian
- Department of Biochemistry and Molecular Biology and the Cardiovascular Research Institute, Wayne State University, School of Medicine, Detroit, Michigan, USA
| | - Timothy L Stemmler
- Department of Biochemistry and Molecular Biology and the Cardiovascular Research Institute, Wayne State University, School of Medicine, Detroit, Michigan, USA
| | - José M Argüello
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts, USA.
| | - Amy C Rosenzweig
- Departments of Molecular Biosciences and of Chemistry. Northwestern University, Evanston, Illinois, USA.
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25
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Nilsson L, Ådén J, Niemiec MS, Nam K, Wittung-Stafshede P. Small pH and Salt Variations Radically Alter the Thermal Stability of Metal-Binding Domains in the Copper Transporter, Wilson Disease Protein. J Phys Chem B 2013; 117:13038-50. [DOI: 10.1021/jp402415y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lina Nilsson
- Chemistry
Department and ‡Computational Life Science Center (CLiC), Umeå University, 90187 Umeå, Sweden
| | - Jörgen Ådén
- Chemistry
Department and ‡Computational Life Science Center (CLiC), Umeå University, 90187 Umeå, Sweden
| | - Moritz S. Niemiec
- Chemistry
Department and ‡Computational Life Science Center (CLiC), Umeå University, 90187 Umeå, Sweden
| | - Kwangho Nam
- Chemistry
Department and ‡Computational Life Science Center (CLiC), Umeå University, 90187 Umeå, Sweden
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26
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Conformations of the apo-, substrate-bound and phosphate-bound ATP-binding domain of the Cu(II) ATPase CopB illustrate coupling of domain movement to the catalytic cycle. Biosci Rep 2013; 32:443-53. [PMID: 22663904 PMCID: PMC3475447 DOI: 10.1042/bsr20120048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Heavy metal P1B-type ATPases play a critical role in cell survival by maintaining appropriate intracellular metal concentrations. Archaeoglobus fulgidus CopB is a member of this family that transports Cu(II) from the cytoplasm to the exterior of the cell using ATP as energy source. CopB has a 264 amino acid ATPBD (ATP-binding domain) that is essential for ATP binding and hydrolysis as well as ultimately transducing the energy to the transmembrane metal-binding site for metal occlusion and export. The relevant conformations of this domain during the different steps of the catalytic cycle are still under discussion. Through crystal structures of the apo- and phosphate-bound ATPBDs, with limited proteolysis and fluorescence studies of the apo- and substrate-bound states, we show that the isolated ATPBD of CopB cycles from an open conformation in the apo-state to a closed conformation in the substrate-bound state, then returns to an open conformation suitable for product release. The present work is the first structural report of an ATPBD with its physiologically relevant product (phosphate) bound. The solution studies we have performed help resolve questions on the potential influence of crystal packing on domain conformation. These results explain how phosphate is co-ordinated in ATPase transporters and give an insight into the physiologically relevant conformation of the ATPBD at different steps of the catalytic cycle.
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27
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Padilla-Benavides T, McCann CJ, Argüello JM. The mechanism of Cu+ transport ATPases: interaction with CU+ chaperones and the role of transient metal-binding sites. J Biol Chem 2012. [PMID: 23184962 DOI: 10.1074/jbc.m112.420810] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cu(+)-ATPases are membrane proteins that couple the hydrolysis of ATP to the efflux of cytoplasmic Cu(+). In cells, soluble chaperone proteins bind and distribute cytoplasmic Cu(+), delivering the ion to the transmembrane metal-binding sites in the ATPase. The structure of Legionella pneumophila Cu(+)-ATPase (Gourdon, P., Liu, X. Y., Skjørringe, T., Morth, J. P., Møller, L. B., Pedersen, B. P., and Nissen, P. (2011) Nature 475, 59-64) shows that a kinked transmembrane segment forms a "platform" exposed to the cytoplasm. In addition, neighboring invariant Met, Asp, and Glu are located at the "entrance" of the ion path. Mutations of amino acids in these regions of the Archaeoglobus fulgidus Cu(+)-ATPase CopA do not affect ATPase activity in the presence of Cu(+) free in solution. However, Cu(+) bound to the corresponding chaperone (CopZ) could not activate the mutated ATPases, and in parallel experiments, CopZ was unable to transfer Cu(+) to CopA. Furthermore, mutation of a specific electronegative patch on the CopZ surface abolishes the ATPase activation and Cu(+) transference, indicating that the region is required for the CopZ-CopA interaction. Moreover, the data suggest that the interaction is driven by the complementation of the electropositive platform in the ATPase and the electronegative Cu(+) chaperone. This docking likely places the Cu(+) proximal to the conserved carboxyl and thiol groups in the entrance site that induce metal release from the chaperone via ligand exchange. The initial interaction of Cu(+) with the pump is transient because Cu(+) is transferred from the entrance site to transmembrane metal-binding sites involved in transmembrane translocation.
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Affiliation(s)
- Teresita Padilla-Benavides
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA
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28
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Gupta A, Lutsenko S. Evolution of copper transporting ATPases in eukaryotic organisms. Curr Genomics 2012; 13:124-33. [PMID: 23024604 PMCID: PMC3308323 DOI: 10.2174/138920212799860661] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 09/22/2011] [Accepted: 09/29/2011] [Indexed: 11/22/2022] Open
Abstract
Copper is an essential nutrient for most life forms, however in excess it can be harmful. The ATP-driven copper pumps (Copper-ATPases) play critical role in living organisms by maintaining appropriate copper levels in cells and tissues. These evolutionary conserved polytopic membrane proteins are present in all phyla from simplest life forms (bacteria) to highly evolved eukaryotes (Homo sapiens). The presumed early function in metal detoxification remains the main function of Copper-ATPases in prokaryotic kingdom. In eukaryotes, in addition to removing excess copper from the cell, Copper-ATPases have another equally important function - to supply copper to copper dependent enzymes within the secretory pathway. This review focuses on the origin and diversification of Copper ATPases in eukaryotic organisms. From a single Copper ATPase in protozoans, a divergence into two functionally distinct ATPases is observed with the evolutionary appearance of chordates. Among the key functional domains of Copper-ATPases, the metal-binding N-terminal domain could be responsible for functional diversification of the copper ATPases during the course of evolution.
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Affiliation(s)
- Arnab Gupta
- Department of Physiology, Johns Hopkins University, Baltimore, MD 21205, USA
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29
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Hasan NM, Gupta A, Polishchuk E, Yu CH, Polishchuk R, Dmitriev OY, Lutsenko S. Molecular events initiating exit of a copper-transporting ATPase ATP7B from the trans-Golgi network. J Biol Chem 2012; 287:36041-50. [PMID: 22898812 DOI: 10.1074/jbc.m112.370403] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The copper-transporting ATPase ATP7B has a dual intracellular localization: the trans-Golgi network (TGN) and cytosolic vesicles. Changes in copper levels, kinase-mediated phosphorylation, and mutations associated with Wilson disease alter the steady-state distribution of ATP7B between these compartments. To identify a primary molecular event that triggers ATP7B exit from the TGN, we characterized the folding, activity, and trafficking of the ATP7B variants with mutations within the regulatory N-terminal domain (N-ATP7B). We found that structural changes disrupting the inter-domain contacts facilitate ATP7B exit from the TGN. Mutating Ser-340/341 in the N-ATP7B individually or together to Ala, Gly, Thr, or Asp produced active protein and shifted the steady-state localization of ATP7B to vesicles, independently of copper levels. The Ser340/341G mutant had a lower kinase-mediated phosphorylation under basal conditions and no copper-dependent phosphorylation. Thus, negative charges introduced by copper-dependent phosphorylation are not obligatory for ATP7B trafficking from the TGN. The Ser340/341A mutation did not alter the overall fold of N-ATP7B, but significantly decreased interactions with the nucleotide-binding domain, mimicking consequences of copper binding to N-ATP7B. We propose that structural changes that specifically alter the inter-domain contacts initiate exit of ATP7B from the TGN, whereas increased phosphorylation may be needed to maintain an open interface between the domains.
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Affiliation(s)
- Nesrin M Hasan
- Department of Physiology, Johns Hopkins University, Baltimore, Maryland 21205, USA
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30
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Keller AM, Benítez JJ, Klarin D, Zhong L, Goldfogel M, Yang F, Chen TY, Chen P. Dynamic multibody protein interactions suggest versatile pathways for copper trafficking. J Am Chem Soc 2012; 134:8934-43. [PMID: 22578168 DOI: 10.1021/ja3018835] [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
As part of intracellular copper trafficking pathways, the human copper chaperone Hah1 delivers Cu(+) to the Wilson's Disease Protein (WDP) via weak and dynamic protein-protein interactions. WDP contains six homologous metal binding domains (MBDs) connected by flexible linkers, and these MBDs all can receive Cu(+) from Hah1. The functional roles of the MBD multiplicity in Cu(+) trafficking are not well understood. Building on our previous study of the dynamic interactions between Hah1 and the isolated fourth MBD of WDP, here we study how Hah1 interacts with MBD34, a double-domain WDP construct, using single-molecule fluorescence resonance energy transfer (smFRET) combined with vesicle trapping. By alternating the positions of the smFRET donor and acceptor, we systematically probed Hah1-MBD3, Hah1-MBD4, and MBD3-MBD4 interaction dynamics within the multidomain system. We found that the two interconverting interaction geometries were conserved in both intermolecular Hah1-MBD and intramolecular MBD-MBD interactions. The Hah1-MBD interactions within MBD34 are stabilized by an order of magnitude relative to the isolated single-MBDs, and thermodynamic and kinetic evidence suggest that Hah1 can interact with both MBDs simultaneously. The enhanced interaction stability of Hah1 with the multi-MBD system, the dynamic intramolecular MBD-MBD interactions, and the ability of Hah1 to interact with multiple MBDs simultaneously suggest an efficient and versatile mechanism for the Hah1-to-WDP pathway to transport Cu(+).
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Affiliation(s)
- Aaron M Keller
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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31
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Huster D, Kühne A, Bhattacharjee A, Raines L, Jantsch V, Noe J, Schirrmeister W, Sommerer I, Sabri O, Berr F, Mössner J, Stieger B, Caca K, Lutsenko S. Diverse functional properties of Wilson disease ATP7B variants. Gastroenterology 2012; 142:947-956.e5. [PMID: 22240481 PMCID: PMC3461965 DOI: 10.1053/j.gastro.2011.12.048] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Revised: 12/19/2011] [Accepted: 12/26/2011] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Wilson disease is a severe disorder of copper metabolism caused by mutations in ATP7B, which encodes a copper-transporting adenosine triphosphatase. The disease presents with a variable phenotype that complicates the diagnostic process and treatment. Little is known about the mechanisms that contribute to the different phenotypes of the disease. METHODS We analyzed 28 variants of ATP7B from patients with Wilson disease that affected different functional domains; the gene products were expressed using the baculovirus expression system in Sf9 cells. Protein function was analyzed by measuring catalytic activity and copper ((64)Cu) transport into vesicles. We studied intracellular localization of variants of ATP7B that had measurable transport activities and were tagged with green fluorescent protein in mammalian cells using confocal laser scanning microscopy. RESULTS Properties of ATP7B variants with pathogenic amino-acid substitution varied greatly even if substitutions were in the same functional domain. Some variants had complete loss of catalytic and transport activity, whereas others lost transport activity but retained phosphor-intermediate formation or had partial losses of activity. In mammalian cells, transport-competent variants differed in stability and subcellular localization. CONCLUSIONS Variants in ATP7B associated with Wilson disease disrupt the protein's transport activity, result in its mislocalization, and reduce its stability. Single assays are insufficient to accurately predict the effects of ATP7B variants the function of its product and development of Wilson disease. These findings will contribute to our understanding of genotype-phenotype correlation and mechanisms of disease pathogenesis.
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Affiliation(s)
- Dominik Huster
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany.
| | - Angelika Kühne
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany
| | | | - Lily Raines
- Department of Physiology, Johns Hopkins University, Baltimore, Maryland
| | - Vanessa Jantsch
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany
| | - Johannes Noe
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, Zurich, Switzerland
| | - Wiebke Schirrmeister
- Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke-University, Magdeburg, Germany,Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Ines Sommerer
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany
| | - Osama Sabri
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Frieder Berr
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany,Department of Internal Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Joachim Mössner
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany
| | - Bruno Stieger
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, Zurich, Switzerland
| | - Karel Caca
- Department of Medicine, Dermatology and Neurology, Division of Gastroenterology and Rheumatology, University of Leipzig, Leipzig, Germany,Department of Gastroenterology, Medizinische Klinik I, Klinikum Ludwigsburg, Ludwigsburg, Germany
| | - Svetlana Lutsenko
- Department of Physiology, Johns Hopkins University, Baltimore, Maryland
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32
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Lepori MB, Zappu A, Incollu S, Dessì V, Mameli E, Demelia L, Nurchi AM, Gheorghe L, Maggiore G, Sciveres M, Leuzzi V, Indolfi G, Bonafé L, Casali C, Angeli P, Barone P, Cao A, Loudianos G. Mutation analysis of the ATP7B gene in a new group of Wilson's disease patients: contribution to diagnosis. Mol Cell Probes 2012; 26:147-50. [PMID: 22484412 DOI: 10.1016/j.mcp.2012.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 03/05/2012] [Accepted: 03/14/2012] [Indexed: 01/23/2023]
Abstract
Wilson's disease (WD), an autosomal recessive disorder of copper transport with a broad range of genotypic and phenotypic characteristics, results from mutations in the ATP7B gene. Herein we report the results of mutation analysis of the ATP7B gene in a group of 118 Wilson disease families (236 chromosomes) prevalently of Italian origin. Using DNA sequencing we identified 83 disease-causing mutations. Eleven were novel, while twenty one already described mutations were identified in new populations in this study. In particular, mutation analysis of 13 families of Romanian origin showed a high prevalence of the p.H1069Q mutation (50%). Detection of new mutations in the ATP7B gene in new populations increases our capability of molecular analysis that is essential for early diagnosis and treatment of WD.
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33
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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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34
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Hasan NM, Lutsenko S. Regulation of copper transporters in human cells. CURRENT TOPICS IN MEMBRANES 2012; 69:137-61. [PMID: 23046650 DOI: 10.1016/b978-0-12-394390-3.00006-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Copper is essential for normal growth and development of human organisms. The role of copper as a cofactor of important metabolic enzymes, such as cytochrome c oxidase, superoxide dismutase, lysyl oxidase, dopamine-β-hydroxylase, and many others, has been well established. In recent years, new regulatory roles of copper have emerged. Accumulating evidence points to the involvement of copper in lipid metabolism, antimicrobial defense, neuronal activity, resistance of tumor cells to platinum-based chemotherapeutic drugs, kinase-mediated signal transduction, and other essential cellular processes. For many of these processes, the precise mechanism of copper action remains to be established. Nevertheless, it is increasingly clear that many regulatory and signaling events are associated with changes in the intracellular localization and abundance of copper transporters, as well as distinct compartmentalization of copper itself. In this review, we discuss current data on regulation of the localization and abundance of copper transporters in response to metabolic and signaling events in human cells. Regulation by kinase-mediated phosphorylation will be addressed along with the emerging area of the redox-driven control of copper transport. We highlight mechanistic questions that await further testing.
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Affiliation(s)
- Nesrin M Hasan
- Department of Physiology, Johns Hopkins University, Baltimore, MD, USA
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35
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Cyanobacterial metallochaperone inhibits deleterious side reactions of copper. Proc Natl Acad Sci U S A 2011; 109:95-100. [PMID: 22198771 DOI: 10.1073/pnas.1117515109] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Copper metallochaperones supply copper to cupro-proteins through copper-mediated protein-protein-interactions and it has been hypothesized that metallochaperones thereby inhibit copper from causing damage en route. Evidence is presented in support of this latter role for cyanobacterial metallochaperone, Atx1. In cyanobacteria Atx1 contributes towards the supply of copper to plastocyanin inside thylakoids but it is shown here that in copper-replete medium, copper can reach plastocyanin without Atx1. Unlike metallochaperone-independent copper-supply to superoxide dismutase in eukaryotes, glutathione is not essential for Atx1-independent supply to plastocyanin: Double mutants missing atx1 and gshB (encoding glutathione synthetase) accumulate the same number of atoms of copper per cell in the plastocyanin pool as wild type. Critically, Δatx1ΔgshB are hypersensitive to elevated copper relative to wild type cells and also relative to ΔgshB single mutants with evidence that hypersensitivity arises due to the mislocation of copper to sites for other metals including iron and zinc. The zinc site on the amino-terminal domain (ZiaA(N)) of the P(1)-type zinc-transporting ATPase is especially similar to the copper site of the Atx1 target PacS(N), and ZiaA(N) will bind Cu(I) more tightly than zinc. An NMR model of a substituted-ZiaA(N)-Cu(I)-Atx1 heterodimer has been generated making it possible to visualize a juxtaposition of residues surrounding the ZiaA(N) zinc site, including Asp(18), which normally repulse Atx1. Equivalent repulsion between bacterial copper metallochaperones and the amino-terminal regions of P(1)-type ATPases for metals other than Cu(I) is conserved, again consistent with a role for copper metallochaperones to withhold copper from binding sites for other metals.
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36
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Hercend C, Bauvais C, Bollot G, Delacotte N, Chappuis P, Woimant F, Launay JM, Manivet P. Elucidation of the ATP7B N-domain Mg2+-ATP coordination site and its allosteric regulation. PLoS One 2011; 6:e26245. [PMID: 22046264 PMCID: PMC3203118 DOI: 10.1371/journal.pone.0026245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2011] [Accepted: 09/23/2011] [Indexed: 11/25/2022] Open
Abstract
The diagnostic of orphan genetic disease is often a puzzling task as less attention is paid to the elucidation of the pathophysiology of these rare disorders at the molecular level. We present here a multidisciplinary approach using molecular modeling tools and surface plasmonic resonance to study the function of the ATP7B protein, which is impaired in the Wilson disease. Experimentally validated in silico models allow the elucidation in the Nucleotide binding domain (N-domain) of the Mg2+-ATP coordination site and answer to the controversial role of the Mg2+ ion in the nucleotide binding process. The analysis of protein motions revealed a substantial effect on a long flexible loop branched to the N-domain protein core. We demonstrated the capacity of the loop to disrupt the interaction between Mg2+-ATP complex and the N-domain and propose a role for this loop in the allosteric regulation of the nucleotide binding process.
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Affiliation(s)
- Claude Hercend
- APHP, Hôpital Lariboisière, Service de Biochimie et de Biologie Moléculaire, Paris, France
- INSERM U942, Biomarqueurs et Insuffisance cardiaque, Hôpital Lariboisière, Paris, France
| | - Cyril Bauvais
- Division of Structural Biology, Bioquanta, Paris, France
| | | | | | - Philippe Chappuis
- APHP, Hôpital Lariboisière, Service de Biochimie et de Biologie Moléculaire, Paris, France
| | - France Woimant
- APHP, Hôpital Lariboisière, Service de Neurologie, Paris, France
| | - Jean-Marie Launay
- APHP, Hôpital Lariboisière, Service de Biochimie et de Biologie Moléculaire, Paris, France
- INSERM U942, Biomarqueurs et Insuffisance cardiaque, Hôpital Lariboisière, Paris, France
| | - Philippe Manivet
- APHP, Hôpital Lariboisière, Service de Biochimie et de Biologie Moléculaire, Paris, France
- INSERM U829, SABNP Laboratory, Evry, France
- Université Evry Val-d'Essonne, Evry, France
- * E-mail:
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37
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Argüello JM, González-Guerrero M, Raimunda D. Bacterial transition metal P(1B)-ATPases: transport mechanism and roles in virulence. Biochemistry 2011; 50:9940-9. [PMID: 21999638 DOI: 10.1021/bi201418k] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
P(1B)-type ATPases are polytopic membrane proteins that couple the hydrolysis of ATP to the efflux of cytoplasmic transition metals. This paper reviews recent progress in our understanding of the structure and function of these proteins in bacteria. These are members of the P-type superfamily of transport ATPases. Cu(+)-ATPases are the most frequently observed and best-characterized members of this group of transporters. However, bacterial genomes show diverse arrays of P(1B)-type ATPases with a range of substrates (Cu(+), Zn(2+), Co(2+)). Furthermore, because of the structural similarities among transitions metals, these proteins can also transport nonphysiological substrates (Cd(2+), Pb(2+), Au(+), Ag(+)). P(1B)-type ATPases have six or eight transmembrane segments (TM) with metal coordinating amino acids in three core TMs flanking the cytoplasmic domain responsible for ATP binding and hydrolysis. In addition, regulatory cytoplasmic metal binding domains are present in most P(1B)-type ATPases. Central to the transport mechanism is the binding of the uncomplexed metal to these proteins when cytoplasmic substrates are bound to chaperone and chelating molecules. Metal binding to regulatory sites is through a reversible metal exchange among chaperones and cytoplasmic metal binding domains. In contrast, the chaperone-mediated metal delivery to transport sites appears as a largely irreversible event. P(1B)-ATPases have two overarching physiological functions: to maintain cytoplasmic metal levels and to provide metals for the periplasmic assembly of metalloproteins. Recent studies have shown that both roles are critical for bacterial virulence, since P(1B)-ATPases appear key to overcome high phagosomal metal levels and are required for the assembly of periplasmic and secreted metalloproteins that are essential for survival in extreme oxidant environments.
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Affiliation(s)
- José M Argüello
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA.
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38
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Incollu S, Lepori MB, Zappu A, Dessì V, Noli MC, Mameli E, Iorio R, Ranucci G, Cao A, Loudianos G. DNA and RNA studies for molecular characterization of a gross deletion detected in homozygosity in the NH2-terminal region of the ATP7B gene in a Wilson disease patient. Mol Cell Probes 2011; 25:195-8. [PMID: 21925265 DOI: 10.1016/j.mcp.2011.07.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 07/08/2011] [Accepted: 07/27/2011] [Indexed: 01/19/2023]
Abstract
Wilson disease is an autosomal recessive disorder caused by defective function of the copper transporting protein ATP7B. Approximately 520 Wilson disease-causing mutations have been described to date. In this study we report the use of DNA and RNA analysis for molecular characterization of a gross deletion of the ATP7B gene detected in homozygosity in a Wilson disease patient. The c.51+384_1708-953del mutation spans an 8798 bp region of the ATP7B gene from exon 2 to intron 4. The results obtained suggest that the combination of DNA and RNA analyses can be used for molecular characterization of gross ATP7B deletions, thus improving genetic counselling and diagnosis of Wilson disease. Moreover these studies, help to better establish the molecular mechanisms producing Wilson disease.
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Affiliation(s)
- Simona Incollu
- Dipartimento di Scienze Biomediche e Biotecnologie, USC, Cagliari, Italy
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39
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Allen GS, Wu CC, Cardozo T, Stokes DL. The architecture of CopA from Archeaoglobus fulgidus studied by cryo-electron microscopy and computational docking. Structure 2011; 19:1219-32. [PMID: 21820315 DOI: 10.1016/j.str.2011.05.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 05/09/2011] [Accepted: 05/12/2011] [Indexed: 10/17/2022]
Abstract
CopA uses ATP to pump Cu(+) across cell membranes. X-ray crystallography has defined atomic structures of several related P-type ATPases. We have determined a structure of CopA at 10 Å resolution by cryo-electron microscopy of a new crystal form and used computational molecular docking to study the interactions between the N-terminal metal-binding domain (NMBD) and other elements of the molecule. We found that the shorter-chain lipids used to produce these crystals are associated with movements of the cytoplasmic domains, with a novel dimer interface and with disordering of the NMBD, thus offering evidence for the transience of its interaction with the other cytoplasmic domains. Docking identified a binding site that matched the location of the NMBD in our previous structure by cryo-electron microscopy, allowing a more detailed view of its binding configuration and further support for its role in autoinhibition.
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Affiliation(s)
- Gregory S Allen
- Skirball Institute, New York University School of Medicine, New York, NY 10016, USA
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40
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Braiterman L, Nyasae L, Leves F, Hubbard AL. Critical roles for the COOH terminus of the Cu-ATPase ATP7B in protein stability, trans-Golgi network retention, copper sensing, and retrograde trafficking. Am J Physiol Gastrointest Liver Physiol 2011; 301:G69-81. [PMID: 21454443 PMCID: PMC3129927 DOI: 10.1152/ajpgi.00038.2011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
ATP7A and ATP7B are copper-transporting P-type ATPases that are essential to eukaryotic copper homeostasis and must traffic between intracellular compartments to carry out their functions. Previously, we identified a nine-amino acid sequence (F37-E45) in the NH(2) terminus of ATP7B that is required to retain the protein in the Golgi when copper levels are low and target it apically in polarized hepatic cells when copper levels rise. To understand further the mechanisms regulating the intracellular dynamics of ATP7B, using multiple functional assays, we characterized the protein phenotypes of 10 engineered and Wilson disease-associated mutations in the ATP7B COOH terminus in polarized hepatic cells and fibroblasts. We also examined the behavior of a chimera between ATP7B and ATP7A. Our results clearly demonstrate the importance of the COOH terminus of ATP7B in the protein's copper-responsive apical trafficking. L1373 at the end of transmembrane domain 8 is required for protein stability and Golgi retention in low copper, the trileucine motif (L1454-L1456) is required for retrograde trafficking, and the COOH terminus of ATP7B exhibits a higher sensitivity to copper than does ATP7A. Importantly, our results demonstrating that four Wilson disease-associated missense mutations behaved in a wild-type manner in all our assays, together with current information in the literature, raise the possibility that several may not be disease-causing mutations.
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Affiliation(s)
- L. Braiterman
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - L. Nyasae
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - F. Leves
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - A. L. Hubbard
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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41
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Raimunda D, González-Guerrero M, Leeber BW, Argüello JM. The transport mechanism of bacterial Cu+-ATPases: distinct efflux rates adapted to different function. Biometals 2011; 24:467-75. [PMID: 21210186 DOI: 10.1007/s10534-010-9404-3] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 12/22/2010] [Indexed: 12/11/2022]
Abstract
Cu(+)-ATPases play a key role in bacterial Cu(+) homeostasis by participating in Cu(+) detoxification and cuproprotein assembly. Characterization of Archaeoglobus fulgidus CopA, a model protein within the subfamily of P(1B-1) type ATPases, has provided structural and mechanistic details on this group of transporters. Atomic resolution structures of cytoplasmic regulatory metal binding domains (MBDs) and catalytic actuator, phosphorylation, and nucleotide binding domains are available. These, in combination with whole protein structures resulting from cryo-electron microscopy analyses, have enabled the initial modeling of these transporters. Invariant residues in helixes 6, 7 and 8 form two transmembrane metal binding sites (TM-MBSs). These bind Cu(+) with high affinity in a trigonal planar geometry. The cytoplasmic Cu(+) chaperone CopZ transfers the metal directly to the TM-MBSs; however, loading both of the TM-MBSs requires binding of nucleotides to the enzyme. In agreement with the classical transport mechanism of P-type ATPases, occupancy of both transmembrane sites by cytoplasmic Cu(+) is a requirement for enzyme phosphorylation and subsequent transport into the periplasmic or extracellular milieus. Recent transport studies have shown that all Cu(+)-ATPases drive cytoplasmic Cu(+) efflux, albeit with quite different transport rates in tune with their various physiological roles. Archetypical Cu(+)-efflux pumps responsible for Cu(+) tolerance, like the Escherichia coli CopA, have turnover rates ten times higher than those involved in cuproprotein assembly (or alternative functions). This explains the incapability of the latter group to significantly contribute to the metal efflux required for survival in high copper environments.
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Affiliation(s)
- Daniel Raimunda
- Department of Chemistry and Biochemistry, Worcester Polytechnic Institute, Worcester, MA 01609, USA
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42
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Agarwal S, Hong D, Desai NK, Sazinsky MH, Argüello JM, Rosenzweig AC. Structure and interactions of the C-terminal metal binding domain of Archaeoglobus fulgidus CopA. Proteins 2010; 78:2450-8. [PMID: 20602459 DOI: 10.1002/prot.22753] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Cu(+)-ATPase CopA from Archaeoglobus fulgidus belongs to the P(1B) family of the P-type ATPases. These integral membrane proteins couple the energy of ATP hydrolysis to heavy metal ion translocation across membranes. A defining feature of P(1B-1)-type ATPases is the presence of soluble metal binding domains at the N-terminus (N-MBDs). The N-MBDs exhibit a conserved ferredoxin-like fold, similar to that of soluble copper chaperones, and bind metal ions via a conserved CXXC motif. The N-MBDs enable Cu(+) regulation of turnover rates apparently through Cu-sensitive interactions with catalytic domains. A. fulgidus CopA is unusual in that it contains both an N-terminal MBD and a C-terminal MBD (C-MBD). The functional role of the unique C-MBD has not been established. Here, we report the crystal structure of the apo, oxidized C-MBD to 2.0 A resolution. In the structure, two C-MBD monomers form a domain-swapped dimer, which has not been observed previously for similar domains. In addition, the interaction of the C-MBD with the other cytoplasmic domains of CopA, the ATP binding domain (ATPBD) and actuator domain (A-domain), has been investigated. Interestingly, the C-MBD interacts specifically with both of these domains, independent of the presence of Cu(+) or nucleotides. These data reinforce the uniqueness of the C-MBD and suggest a distinct structural role for the C-MBD in CopA transport.
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Affiliation(s)
- Sorabh Agarwal
- Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston, Illinois 60208, USA
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43
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Fatemi N, Korzhnev DM, Velyvis A, Sarkar B, Forman-Kay JD. NMR Characterization of Copper-Binding Domains 4−6 of ATP7B,. Biochemistry 2010; 49:8468-77. [DOI: 10.1021/bi1008535] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Negah Fatemi
- Department of Biochemistry
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | | | - Algirdas Velyvis
- Department of Biochemistry
- Departments of Chemistry and Medical Genetics
| | - Bibudhendra Sarkar
- Department of Biochemistry
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Julie D. Forman-Kay
- Department of Biochemistry
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
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44
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Traverso ME, Subramanian P, Davydov R, Hoffman BM, Stemmler TL, Rosenzweig AC. Identification of a hemerythrin-like domain in a P1B-type transport ATPase. Biochemistry 2010; 49:7060-8. [PMID: 20672819 PMCID: PMC2935145 DOI: 10.1021/bi100866b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The P(1B)-type ATPases couple the energy of ATP hydrolysis to metal ion translocation across cell membranes. Important for prokaryotic metal resistance and essential metal distribution in eukaryotes, P(1B)-ATPases are divided into subclasses on the basis of their metal substrate specificities. Sequence analysis of putative P(1B-5)-ATPases, for which the substrate has not been identified, led to the discovery of a C-terminal soluble domain homologous to hemerythrin (Hr) proteins and domains. The Hr domain from the Acidothermus cellulolyticus P(1B-5)-ATPase was cloned, expressed, and purified (P(1B-5)-Hr). P(1B-5)-Hr binds two iron ions per monomer and adopts a predominantly helical fold. Optical absorption features of the iron-loaded and azide-treated protein are consistent with features observed for other Hr proteins. Autoxidation to the met form is very rapid, as reported for other prokaryotic Hr domains. The presence of a diiron center was confirmed by electron paramagnetic resonance (EPR) and X-ray absorption spectroscopic (XAS) data. The occurrence of a Hr-like domain in a P-type ATPase is unprecedented and suggests new regulatory mechanisms as well as an expanded function for Hr proteins in biology.
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Affiliation(s)
- Matthew E. Traverso
- Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston IL 60208
- Department of Chemistry, Northwestern University, Evanston IL 60208
| | - Poorna Subramanian
- Department of Biochemistry and Molecular Biology, Wayne State University, School of Medicine, Detroit MI 48202
| | - Roman Davydov
- Department of Chemistry, Northwestern University, Evanston IL 60208
| | - Brian M. Hoffman
- Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston IL 60208
- Department of Chemistry, Northwestern University, Evanston IL 60208
| | - Timothy L. Stemmler
- Department of Biochemistry and Molecular Biology, Wayne State University, School of Medicine, Detroit MI 48202
| | - Amy C. Rosenzweig
- Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston IL 60208
- Department of Chemistry, Northwestern University, Evanston IL 60208
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45
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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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46
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Abstract
The current state of knowledge on how copper metallochaperones support the maturation of cuproproteins is reviewed. Copper is needed within mitochondria to supply the Cu(A) and intramembrane Cu(B) sites of cytochrome oxidase, within the trans-Golgi network to supply secreted cuproproteins and within the cytosol to supply superoxide dismutase 1 (Sod1). Subpopulations of copper-zinc superoxide dismutase also localize to mitochondria, the secretory system, the nucleus and, in plants, the chloroplast, which also requires copper for plastocyanin. Prokaryotic cuproproteins are found in the cell membrane and in the periplasm of gram-negative bacteria. Cu(I) and Cu(II) form tight complexes with organic molecules and drive redox chemistry, which unrestrained would be destructive. Copper metallochaperones assist copper in reaching vital destinations without inflicting damage or becoming trapped in adventitious binding sites. Copper ions are specifically released from copper metallochaperones upon contact with their cognate cuproproteins and metal transfer is thought to proceed by ligand substitution.
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Affiliation(s)
- Nigel J Robinson
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, NE2 4HH, United Kingdom.
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47
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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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48
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Robinson NJ, Winge DR. Copper metallochaperones. Annu Rev Biochem 2010. [PMID: 20205585 DOI: 10.1146/annurev-biochem-030409-143539]+[] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The current state of knowledge on how copper metallochaperones support the maturation of cuproproteins is reviewed. Copper is needed within mitochondria to supply the Cu(A) and intramembrane Cu(B) sites of cytochrome oxidase, within the trans-Golgi network to supply secreted cuproproteins and within the cytosol to supply superoxide dismutase 1 (Sod1). Subpopulations of copper-zinc superoxide dismutase also localize to mitochondria, the secretory system, the nucleus and, in plants, the chloroplast, which also requires copper for plastocyanin. Prokaryotic cuproproteins are found in the cell membrane and in the periplasm of gram-negative bacteria. Cu(I) and Cu(II) form tight complexes with organic molecules and drive redox chemistry, which unrestrained would be destructive. Copper metallochaperones assist copper in reaching vital destinations without inflicting damage or becoming trapped in adventitious binding sites. Copper ions are specifically released from copper metallochaperones upon contact with their cognate cuproproteins and metal transfer is thought to proceed by ligand substitution.
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Affiliation(s)
- Nigel J Robinson
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, NE2 4HH, United Kingdom.
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49
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Abstract
The current state of knowledge on how copper metallochaperones support the maturation of cuproproteins is reviewed. Copper is needed within mitochondria to supply the Cu(A) and intramembrane Cu(B) sites of cytochrome oxidase, within the trans-Golgi network to supply secreted cuproproteins and within the cytosol to supply superoxide dismutase 1 (Sod1). Subpopulations of copper-zinc superoxide dismutase also localize to mitochondria, the secretory system, the nucleus and, in plants, the chloroplast, which also requires copper for plastocyanin. Prokaryotic cuproproteins are found in the cell membrane and in the periplasm of gram-negative bacteria. Cu(I) and Cu(II) form tight complexes with organic molecules and drive redox chemistry, which unrestrained would be destructive. Copper metallochaperones assist copper in reaching vital destinations without inflicting damage or becoming trapped in adventitious binding sites. Copper ions are specifically released from copper metallochaperones upon contact with their cognate cuproproteins and metal transfer is thought to proceed by ligand substitution.
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Affiliation(s)
- Nigel J Robinson
- Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, NE2 4HH, United Kingdom.
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50
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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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