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Dmitriev OY, Patry J. Structure and mechanism of the human copper transporting ATPases: Fitting the pieces into a moving puzzle. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184306. [PMID: 38408697 DOI: 10.1016/j.bbamem.2024.184306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 02/07/2024] [Accepted: 02/18/2024] [Indexed: 02/28/2024]
Abstract
Human copper transporters ATP7B and ATP7A deliver copper to biosynthetic pathways and maintain copper homeostasis in the cell. These enzymes combine several challenges for structural biology because they are large low abundance membrane proteins with many highly mobile domains and long disordered loops. No method has yet succeeded in solving the structure of the complete fully functional protein. Still, X-ray crystallography, Cryo-EM and NMR helped to piece together a structure based model of the enzyme activity and regulation by copper. We review the structures of ATP7B and ATP7A with an emphasis on the mechanistic insights into the unique aspects of the transport function and regulation of the human copper ATPases that have emerged from more than twenty years of research.
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Affiliation(s)
- Oleg Y Dmitriev
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, Canada.
| | - Jaala Patry
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
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2
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Stalke A, Behrendt A, Hennig F, Gohlke H, Buhl N, Reinkens T, Baumann U, Schlegelberger B, Illig T, Pfister ED, Skawran B. Functional characterization of novel or yet uncharacterized ATP7B missense variants detected in patients with clinical Wilson's disease. Clin Genet 2023. [PMID: 37157876 DOI: 10.1111/cge.14352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 04/14/2023] [Accepted: 04/20/2023] [Indexed: 05/10/2023]
Abstract
Wilson's disease (WD, MIM#277900) is an autosomal recessive disorder resulting in copper excess caused by biallelic variants in the ATP7B gene (MIM#606882) encoding a copper transporting P-type ATPase. ATP7B variants of unknown significance (VUS) are detected frequently, sometimes impeding a clear diagnosis. Functional analyses can help to classify these variants as benign or pathogenic. Additionally, variants already classified as (likely) pathogenic benefit from functional analyses to understand their pathomechanism, thus contribute to the development of personalized treatment approaches in the future. We described clinical features of six WD patients and functionally characterized five ATP7B missense variants (two VUS, three yet uncharacterized likely pathogenic variants), detected in these patients. We determined the protein level, copper export capacity, and cellular localization in an in vitro model and potential structural consequences using an ATP7B protein model based on AlphaFold. Our analyses give insight into the pathomechanism and allowed reclassification for the two VUS to likely pathogenic and for two of the three likely pathogenic variants to pathogenic.
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Affiliation(s)
- Amelie Stalke
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
- Department of Pediatric Gastroenterology and Hepatology, Division of Kidney, Liver, and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Annika Behrendt
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Finja Hennig
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Nicole Buhl
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
- Department of Pediatric Gastroenterology and Hepatology, Division of Kidney, Liver, and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Thea Reinkens
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Ulrich Baumann
- Department of Pediatric Gastroenterology and Hepatology, Division of Kidney, Liver, and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | | | - Thomas Illig
- Hannover Unified Bank, Hannover Medical School, Hannover, Germany
| | - Eva-Doreen Pfister
- Department of Pediatric Gastroenterology and Hepatology, Division of Kidney, Liver, and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Britta Skawran
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
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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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Wang J, Tang L, Xu A, Zhang S, Jiang H, Pei P, Li H, Lv T, Yang Y, Qian N, Naidu K, Yang W. Identification of mutations in the ATP7B gene in 14 Wilson disease children: Case series. Medicine (Baltimore) 2021; 100:e25463. [PMID: 33879678 PMCID: PMC8078297 DOI: 10.1097/md.0000000000025463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 03/18/2021] [Indexed: 01/04/2023] Open
Abstract
INTRODUCTION Wilson Disease (WD) is an autosomal recessive inherited metabolic disease caused by mutations in the ATPase copper transporting beta gene (ATP7B). WD can cause fatal neurological and hepatic disorders if not diagnosed and treated. OBJECTIVE To analyze the disease-causing mutations of 14 Chinese WD children, 11 of whom are diagnosed with hepatic disorders, 2 with neurological degeneration and 1 with both hepatic and neurological disorders. METHODS All ATP7B coding regions were analyzed by Sanger sequencing. Single nucleotide polymorphisms (SNPs) functional impacts were assessed by combining the results of four bioinformatics tools (Poly-phen-2, SIFT, PANTHER-PSEP and PhD-SNPs) in an index that reflects the combined probability (cPdel) of an amino acid change to be deleterious to the protein function. RESULTS Two novel variants involved in WD development, c.1448_1455del (p.Arg483SerfsX19) and c.4144G>T (p.Glu1382Stop), and 11 previously reported mutations were detected. Both new variants result in shortened and dysfunctional ATP7B proteins. cPdel score suggests that SNPs may be deleterious to the ATP7B functionality. CONCLUSIONS This study enriches the library of the ATP7B mutations that lead to WD and can be used as a basis for genetic counseling, for WD prevention and clinical and prenatal diagnosis. Those SNPs that are believed to be harmless to ATP7B protein may be involved in the pathogenesis of WD.
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Affiliation(s)
| | | | - Anqi Xu
- Nangjing Red Cross Blood Center, Nangjing
| | | | | | | | - Hongmei Li
- Clinical Laboratory Center, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei
| | - Tingting Lv
- Department of Rehabilitation Medicine, Laian People's Hospital, Chuzhou
| | | | | | - Keegan Naidu
- School of International Studies, Anhui Medical University, Hefei, Anhui, PR China
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Mhaske A, Dileep K, Kumar M, Poojary M, Pandhare K, Zhang KY, Scaria V, Binukumar B. ATP7A Clinical Genetics Resource - A comprehensive clinically annotated database and resource for genetic variants in ATP7A gene. Comput Struct Biotechnol J 2020; 18:2347-2356. [PMID: 32994893 PMCID: PMC7501406 DOI: 10.1016/j.csbj.2020.08.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/21/2022] Open
Abstract
ATP7A is a critical copper transporter involved in Menkes Disease, Occipital horn Syndrome and X-linked distal spinal muscular atrophy type 3 which are X linked genetic disorders. These are rare diseases and their genetic epidemiology of the diseases is unknown. A number of genetic variants in the genes have been reported in published literature as well as databases, however, understanding the pathogenicity of variants and genetic epidemiology requires the data to be compiled in a unified format. To this end, we systematically compiled genetic variants from published literature and datasets. Each of the variants were systematically evaluated for evidences with respect to their pathogenicity and classified as per the American College of Medical Genetics and the Association of Molecular Pathologists (ACMG-AMP) guidelines into Pathogenic, Likely Pathogenic, Benign, Likely Benign and Variants of Uncertain Significance. Additional integrative analysis of population genomic datasets provides insights into the genetic epidemiology of the disease through estimation of carrier frequencies in global populations. To deliver a mechanistic explanation for the pathogenicity of selected variants, we also performed molecular modeling studies. Our modeling studies concluded that the small structural distortions observed in the local structures of the protein may lead to the destabilization of the global structure. To the best of our knowledge, ATP7A Clinical Genetics Resource is one of the most comprehensive compendium of variants in the gene providing clinically relevant annotations in gene.
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Affiliation(s)
- Aditi Mhaske
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
| | - K.V. Dileep
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Mukesh Kumar
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
| | - Mukta Poojary
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
| | - Kavita Pandhare
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
| | - Kam Y.J. Zhang
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Vinod Scaria
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
- Corresponding author at: CSIR-Institute of Genomics and Integrative Biology (IGIB), Mathura Road, Sukhdev Vihar, New Delhi 110025, India.
| | - B.K. Binukumar
- CSIR Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110 025, India
- Academy of Scientific and Innovative Research, CSIR-IGIB South Campus, Mathura Road, Delhi, India
- Corresponding author at: CSIR-Institute of Genomics and Integrative Biology (IGIB), Mathura Road, Sukhdev Vihar, New Delhi 110025, India.
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McCann CJ, Jayakanthan S, Siotto M, Yang N, Osipova M, Squitti R, Lutsenko S. Single nucleotide polymorphisms in the human ATP7B gene modify the properties of the ATP7B protein. Metallomics 2020; 11:1128-1139. [PMID: 31070637 DOI: 10.1039/c9mt00057g] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Single nucleotide polymorphisms (SNPs) are the largest source of sequence variation in the human genome. However, their functional significance is not well understood. We show that SNPs in the Wilson disease gene, ATP7B, that produce amino-acid substitutions K832R and R952K, modulate ATP7B properties in vitro and influence serum copper (Cu) status in vivo. The presence of R832 is associated with a lower ATP7B abundance and a diminished trafficking in response to elevated Cu. The K832R substitution alters surface exposure of amino acid residues in the actuator domain and increases its conformational flexibility. All SNP-related ATP7B variants (R832/R952, R832/K952, K832/K952, and K832/R952) have Cu-transport activity. However, the activity of ATP7B-K832/K952 is lower compared to other variants. In humans, the presence of K952 is associated with a higher fraction of exchangeable Cu in serum. Thus, SNPs may modulate the properties of ATP7B and the organism Cu status.
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Affiliation(s)
- Courtney J McCann
- Department of Physiology, Johns Hopkins University, Baltimore, MD, USA.
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7
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Yun Y, Hong SA, Kim KK, Baek D, Lee D, Londhe AM, Lee M, Yu J, McEachin ZT, Bassell GJ, Bowser R, Hales CM, Cho SR, Kim J, Pae AN, Cheong E, Kim S, Boulis NM, Bae S, Ha Y. CRISPR-mediated gene correction links the ATP7A M1311V mutations with amyotrophic lateral sclerosis pathogenesis in one individual. Commun Biol 2020; 3:33. [PMID: 31959876 PMCID: PMC6970999 DOI: 10.1038/s42003-020-0755-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 12/17/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a severe disease causing motor neuron death, but a complete cure has not been developed and related genes have not been defined in more than 80% of cases. Here we compared whole genome sequencing results from a male ALS patient and his healthy parents to identify relevant variants, and chose one variant in the X-linked ATP7A gene, M1311V, as a strong disease-linked candidate after profound examination. Although this variant is not rare in the Ashkenazi Jewish population according to results in the genome aggregation database (gnomAD), CRISPR-mediated gene correction of this mutation in patient-derived and re-differentiated motor neurons drastically rescued neuronal activities and functions. These results suggest that the ATP7A M1311V mutation has a potential responsibility for ALS in this patient and might be a potential therapeutic target, revealed here by a personalized medicine strategy.
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Affiliation(s)
- Yeomin Yun
- Department of Neurosurgery, Spine & Spinal Cord Institute, College of Medicine, Yonsei University, Seoul, 03722, South Korea
- Brain Korea 21 PLUS Project for Medical Science, College of Medicine, Yonsei University, Seoul, 03722, South Korea
| | - Sung-Ah Hong
- Department of Chemistry, Hanyang University, Seoul, 04763, South Korea
- Research Institute for Natural Sciences, Hanyang University, Seoul, 04763, South Korea
| | - Ka-Kyung Kim
- Department of Biomedical Systems Informatics, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Daye Baek
- Department of Neurosurgery, Spine & Spinal Cord Institute, College of Medicine, Yonsei University, Seoul, 03722, South Korea
- Brain Korea 21 PLUS Project for Medical Science, College of Medicine, Yonsei University, Seoul, 03722, South Korea
| | - Dongsu Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Ashwini M Londhe
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, PO Box 131, Cheongryang, Seoul, 130-650, South Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul, 02792, South Korea
| | - Minhyung Lee
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, 34113, South Korea
| | - Jihyeon Yu
- Department of Chemistry, Hanyang University, Seoul, 04763, South Korea
| | - Zachary T McEachin
- Laboratory of Translational Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Gary J Bassell
- Laboratory of Translational Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA, 30322, USA
| | - Robert Bowser
- Department of Neurobiology, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, AZ, 85013, USA
| | - Chadwick M Hales
- Department of Neurology, Emory University, Atlanta, GA, 30322, USA
| | - Sung-Rae Cho
- Brain Korea 21 PLUS Project for Medical Science, College of Medicine, Yonsei University, Seoul, 03722, South Korea
- Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Janghwan Kim
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, South Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology, Daejeon, 34113, South Korea
| | - Ae Nim Pae
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, PO Box 131, Cheongryang, Seoul, 130-650, South Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul, 02792, South Korea
| | - Eunji Cheong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Sangwoo Kim
- Department of Biomedical Systems Informatics, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Nicholas M Boulis
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Sangsu Bae
- Department of Chemistry, Hanyang University, Seoul, 04763, South Korea.
- Research Institute for Natural Sciences, Hanyang University, Seoul, 04763, South Korea.
| | - Yoon Ha
- Department of Neurosurgery, Spine & Spinal Cord Institute, College of Medicine, Yonsei University, Seoul, 03722, South Korea.
- Brain Korea 21 PLUS Project for Medical Science, College of Medicine, Yonsei University, Seoul, 03722, South Korea.
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Petruzzelli R, Polishchuk RS. Activity and Trafficking of Copper-Transporting ATPases in Tumor Development and Defense against Platinum-Based Drugs. Cells 2019; 8:E1080. [PMID: 31540259 PMCID: PMC6769697 DOI: 10.3390/cells8091080] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/10/2019] [Accepted: 09/12/2019] [Indexed: 02/06/2023] Open
Abstract
Membrane trafficking pathways emanating from the Golgi regulate a wide range of cellular processes. One of these is the maintenance of copper (Cu) homeostasis operated by the Golgi-localized Cu-transporting ATPases ATP7A and ATP7B. At the Golgi, these proteins supply Cu to newly synthesized enzymes which use this metal as a cofactor to catalyze a number of vitally important biochemical reactions. However, in response to elevated Cu, the Golgi exports ATP7A/B to post-Golgi sites where they promote sequestration and efflux of excess Cu to limit its potential toxicity. Growing tumors actively consume Cu and employ ATP7A/B to regulate the availability of this metal for oncogenic enzymes such as LOX and LOX-like proteins, which confer higher invasiveness to malignant cells. Furthermore, ATP7A/B activity and trafficking allow tumor cells to detoxify platinum (Pt)-based drugs (like cisplatin), which are used for the chemotherapy of different solid tumors. Despite these noted activities of ATP7A/B that favor oncogenic processes, the mechanisms that regulate the expression and trafficking of Cu ATPases in malignant cells are far from being completely understood. This review summarizes current data on the role of ATP7A/B in the regulation of Cu and Pt metabolism in malignant cells and outlines questions and challenges that should be addressed to understand how ATP7A and ATP7B trafficking mechanisms might be targeted to counteract tumor development.
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Affiliation(s)
- Raffaella Petruzzelli
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy.
| | - Roman S Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy.
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Wang Z, Li L, Sun L, Mi Z, Fu F, Yu G, Fu X, Liu H, Zhang F. Review of 52 cases with Hailey-Hailey disease identified 25 novel mutations in Chinese Han population. J Dermatol 2019; 46:1024-1026. [PMID: 31435946 DOI: 10.1111/1346-8138.15055] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/26/2019] [Indexed: 12/18/2022]
Abstract
Hailey-Hailey disease (HHD) is a rare autosomal dominant inherited keratosis caused by mutations in ATP2C1. The aim of our study was to identify and analyze the features of the mutations in HHD. We examined 52 Chinese Han cases which were diagnosed as HHD based on their clinical and histological findings. Genomic DNA polymerase chain reaction and direct sequencing of ATP2C1 were performed from peripheral blood samples of the patients and 100 unrelated healthy controls. Twenty-five novel mutations and 14 recurrent mutations were identified, including 11 (28.2%) missense mutations, nine (23.1%) frame-shift deletion mutations, eight (20.5%) nonsense mutations, seven (17.9%) splicing mutations and four (10.3%) frame-shift insertion mutations. Together with ours, all 209 mutations showed a uniform distribution without hotspots or clusters. In addition, there is no specific genotype-phenotype correlation in HHD. Our findings update the spectrum of mutations in ATP2C1.
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Affiliation(s)
- Zhe Wang
- Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, China.,Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Lulu Li
- Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Lele Sun
- Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Zihao Mi
- Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Fanghui Fu
- Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, China
| | - Gongqi Yu
- Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Xian Fu
- Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Hong Liu
- Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, China.,Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Furen Zhang
- Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, China.,Shandong Provincial Hospital for Skin Diseases and Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
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11
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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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de Gemmis P, Enzo MV, Lorenzetto E, Cattelan P, Segat D, Hladnik U. 13 novel putative mutations in ATP7A found in a cohort of 25 Italian families. Metab Brain Dis 2017; 32:1173-1183. [PMID: 28451781 DOI: 10.1007/s11011-017-0010-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 04/03/2017] [Indexed: 01/09/2023]
Abstract
ATP7A is a copper-transporting P-type adenosine triphosphatase whose loss of function leads to the Menkes disease, an X-linked copper metabolism multi-organ disorder (1 in 100.000 births). Here we document our experience with the ATP7A linked diseases in Italy. We analyzed the exonic structure of the ATP7A gene in 25 unrelated Italian families and studied the variants of unknown significance. We identified 22 different DNA alterations, 13 of which first reported in this study. The classical Menkes phenotype was present in 21 of the 25 families and was linked with highly damaging mutations (7 nonsense; 4 frame-shift; 2 small in-frame deletions, 2 splice site alterations, 2 gross deletions, and 1 gross duplication). Of the 4 cases with milder variants of the Menkes disease two had a missense mutation, one a leaky splice site alteration and one a nonsense mutation in exon 22. We determined in silico that all the mutations leading to the classical Menkes disease leave no residual activity of ATP7A including the apparently less severe in-frame deletions. Whereas milder forms of the disease are characterized by mutations that allow a limited residual activity of ATP7A, including the nonsense mutation observed.
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Affiliation(s)
- Paola de Gemmis
- "Mauro Baschirotto" Institute for Rare Diseases - B.I.R.D. Foundation n.p.o., via B. Bizio, 1 36023, Costozza di Longare, Vicenza, Italy
| | - Maria Vittoria Enzo
- "Mauro Baschirotto" Institute for Rare Diseases - B.I.R.D. Foundation n.p.o., via B. Bizio, 1 36023, Costozza di Longare, Vicenza, Italy
| | - Elisa Lorenzetto
- "Mauro Baschirotto" Institute for Rare Diseases - B.I.R.D. Foundation n.p.o., via B. Bizio, 1 36023, Costozza di Longare, Vicenza, Italy
| | - Paola Cattelan
- "Mauro Baschirotto" Institute for Rare Diseases - B.I.R.D. Foundation n.p.o., via B. Bizio, 1 36023, Costozza di Longare, Vicenza, Italy
| | - Daniela Segat
- "Mauro Baschirotto" Institute for Rare Diseases - B.I.R.D. Foundation n.p.o., via B. Bizio, 1 36023, Costozza di Longare, Vicenza, Italy
| | - Uros Hladnik
- "Mauro Baschirotto" Institute for Rare Diseases - B.I.R.D. Foundation n.p.o., via B. Bizio, 1 36023, Costozza di Longare, Vicenza, Italy.
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13
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Liedschulte V, Laparra H, Battey JND, Schwaar JD, Broye H, Mark R, Klein M, Goepfert S, Bovet L. Impairing both HMA4 homeologs is required for cadmium reduction in tobacco. PLANT, CELL & ENVIRONMENT 2017; 40:364-377. [PMID: 27880006 DOI: 10.1111/pce.12870] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 10/18/2016] [Accepted: 11/15/2016] [Indexed: 05/26/2023]
Abstract
In tobacco, the heavy metal P1B-ATPases HMA4.1 and HMA4.2 function in root-to-shoot zinc and cadmium transport. We present greenhouse and field data that dissect the possibilities to impact the two homeologous genes in order to define the best strategy for leaf cadmium reduction. In a first step, both genes were silenced using an RNAi approach leading to >90% reduction of leaf cadmium content. To modulate HMA4 function more precisely, mutant HMA4.1 and HMA4.2 alleles of a Targeting Induced Local Lesions IN Genomes (TILLING) population were combined. As observed with RNAi plants, knockout of both homeologs decreased cadmium root-to-shoot transfer by >90%. Analysis of plants with segregating null and wild-type alleles of both homeologs showed that one functional HMA4 allele is sufficient to maintain wild-type cadmium levels. Plant development was affected in HMA4 RNAi and double knockout plants that included retarded growth, necrotic lesions, altered leaf morphology and increased water content. The combination of complete functional loss (nonsense mutation) in one homeologous HMA4 gene and the functional reduction in the other HMA4 gene (missense mutation) is proposed as strategy to limit cadmium leaf accumulation without developmental effects.
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Affiliation(s)
- Verena Liedschulte
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Hélène Laparra
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - James Nicolas Duncan Battey
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Joanne Deborah Schwaar
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Hervé Broye
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Régis Mark
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Markus Klein
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Simon Goepfert
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
| | - Lucien Bovet
- PMI R&D, Philip Morris Products SA (part of Philip Morris International group of companies), Neuchâtel, Switzerland
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14
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Tadini-Buoninsegni F, Smeazzetto S. Mechanisms of charge transfer in human copper ATPases ATP7A and ATP7B. IUBMB Life 2017; 69:218-225. [PMID: 28164426 DOI: 10.1002/iub.1603] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/26/2016] [Indexed: 12/30/2022]
Abstract
ATP7A and ATP7B are Cu+ -transporting ATPases of subclass IB and play a fundamental role in intracellular copper homeostasis. ATP7A/B transfer Cu+ ions across the membrane from delivery to acceptor proteins without establishing a free Cu+ gradient. Transfer of copper across the membrane is coupled to ATP hydrolysis. Current measurements on solid supported membranes (SSM) were performed to investigate the mechanism of copper-related charge transfer across ATP7A and ATP7B. SSM measurements demonstrated that electrogenic copper displacement occurs within ATP7A/B following addition of ATP and formation of the phosphorylated intermediate. Comparison of the time constants for cation displacement in ATP7A/B and sarcoplasmic reticulum Ca2+ -ATPase is consistent with the slower phosphoenzyme formation in copper ATPases. Moreover, ATP-dependent copper transfer in ATP7A/B is not affected by varying the pH, suggesting that net proton counter-transport may not occur in copper ATPases. Platinum anticancer drugs activate ATP7A/B and are subjected to ATP-dependent vectorial displacement with a mechanism analogous to that of copper. © 2016 IUBMB Life, 69(4):218-225, 2017.
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Affiliation(s)
| | - Serena Smeazzetto
- Department of Chemistry "Ugo Schiff,", University of Florence, Sesto Fiorentino, Italy
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15
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Inesi G. Molecular features of copper binding proteins involved in copper homeostasis. IUBMB Life 2016; 69:211-217. [PMID: 27896900 DOI: 10.1002/iub.1590] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 11/09/2016] [Indexed: 11/06/2022]
Abstract
Copper has a wide and important role in biological systems, determining conformation and activity of many metalloproteins and enzymes, such as cytochrome oxidase and superoxide dismutase . Furthermore, due to its possible reactivity with nonspecific proteins and toxic effects, elaborate systems of absorption, concentration buffering, delivery to specific protein sites and elimination, require a complex system including small carriers, chaperones and active transporters. The P-type copper ATPases ATP7A and ATP7B provide an important system for acquisition, active transport, distribution and elimination of copper. Relevance of copper metabolism to human diseases and therapy is already known. It is quite certain that further studies will reveal detailed and useful information on biochemical mechanisms and relevance to diseases. © 2016 IUBMB Life, 69(4):211-217, 2017.
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Affiliation(s)
- Giuseppe Inesi
- California Pacific Medical Center Research Institute, San Francisco, California, USA
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16
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Abstract
Copper ATPases, in analogy with other members of the P-ATPase superfamily, contain a catalytic headpiece including an aspartate residue reacting with ATP to form a phosphoenzyme intermediate, and transmembrane helices containing cation-binding sites [TMBS (transmembrane metal-binding sites)] for catalytic activation and cation translocation. Following phosphoenzyme formation by utilization of ATP, bound copper undergoes displacement from the TMBS to the lumenal membrane surface, with no H+ exchange. Although PII-type ATPases sustain active transport of alkali/alkali-earth ions (i.e. Na+, Ca2+) against electrochemical gradients across defined membranes, PIB-type ATPases transfer transition metal ions (i.e. Cu+) from delivery to acceptor proteins and, prominently in mammalian cells, undergo trafficking from/to various membrane compartments. A specific component of copper ATPases is the NMBD (N-terminal metal-binding domain), containing up to six copper-binding sites in mammalian (ATP7A and ATP7B) enzymes. Copper occupancy of NMBD sites and interaction with the ATPase headpiece are required for catalytic activation. Furthermore, in the presence of copper, the NMBD allows interaction with protein kinase D, yielding phosphorylation of serine residues, ATP7B trafficking and protection from proteasome degradation. A specific feature of ATP7A is glycosylation and stabilization on plasma membranes. Cisplatin, a platinum-containing anti-cancer drug, binds to copper sites of ATP7A and ATP7B, and undergoes vectorial displacement in analogy with copper.
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17
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Huang Y, Nokhrin S, Hassanzadeh-Ghassabeh G, Yu CH, Yang H, Barry AN, Tonelli M, Markley JL, Muyldermans S, Dmitriev OY, Lutsenko S. Interactions between metal-binding domains modulate intracellular targeting of Cu(I)-ATPase ATP7B, as revealed by nanobody binding. J Biol Chem 2014; 289:32682-93. [PMID: 25253690 DOI: 10.1074/jbc.m114.580845] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The biologically and clinically important membrane transporters are challenging proteins to study because of their low level of expression, multidomain structure, and complex molecular dynamics that underlies their activity. ATP7B is a copper transporter that traffics between the intracellular compartments in response to copper elevation. The N-terminal domain of ATP7B (N-ATP7B) is involved in binding copper, but the role of this domain in trafficking is controversial. To clarify the role of N-ATP7B, we generated nanobodies that interact with ATP7B in vitro and in cells. In solution NMR studies, nanobodies revealed the spatial organization of N-ATP7B by detecting transient functionally relevant interactions between metal-binding domains 1-3. Modulation of these interactions by nanobodies in cells enhanced relocalization of the endogenous ATP7B toward the plasma membrane linking molecular and cellular dynamics of the transporter. Stimulation of ATP7B trafficking by nanobodies in the absence of elevated copper provides direct evidence for the important role of N-ATP7B structural dynamics in regulation of ATP7B localization in a cell.
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Affiliation(s)
- Yiping Huang
- From the Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Sergiy Nokhrin
- the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Gholamreza Hassanzadeh-Ghassabeh
- the Vrije Universiteit Brussel, Structural Biology Research Center, and Nanobody Service Facility, VIB, 1050 Brussels, Belgium, and
| | - Corey H Yu
- the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Haojun Yang
- From the Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Amanda N Barry
- From the Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Marco Tonelli
- the Department of Biochemistry, National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - John L Markley
- the Department of Biochemistry, National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Serge Muyldermans
- the Vrije Universiteit Brussel, Structural Biology Research Center, and
| | - Oleg Y Dmitriev
- the Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada,
| | - Svetlana Lutsenko
- From the Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205,
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18
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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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19
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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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20
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Schushan M, Bhattacharjee A, Ben-Tal N, Lutsenko S. A structural model of the copper ATPase ATP7B to facilitate analysis of Wilson disease-causing mutations and studies of the transport mechanism. Metallomics 2012; 4:669-78. [PMID: 22692182 DOI: 10.1039/c2mt20025b] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The copper-transporting ATPase ATP7B has an essential role in human physiology, particularly for the liver and brain function. Inactivation of ATP7B is associated with a severe hepato-neurologic disorder, Wilson disease (WD). Hundreds of WD related mutations have been identified in ATP7B to date. The low frequency and the compound-heterozygous nature of causative mutations complicate the analysis of individual mutants and the establishment of genotype-phenotype correlations. To facilitate studies of disease-causing mutations and mechanistic understanding of WD, we have homology-modelled the ATP7B core (residues 643-1377) using the recent structure of the bacterial copper-ATPase LCopA as a template. The model, supported by evolutionary conservation and hydrophobicity analysis, as well as existing and new mutagenesis data, allows molecular interpretations of experimentally characterized clinical mutations. We also illustrate that structure and conservation can be used to grade potential deleterious effects for many WD mutations, which were clinically detected but have not yet been experimentally characterized. Finally, we compare the structural features of ATP7B and LCopA and discuss specific features of the eukaryotic copper pump.
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Affiliation(s)
- Maya Schushan
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Ramat Aviv 69978, Israel.
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21
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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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22
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Rosenzweig AC, Argüello JM. Toward a molecular understanding of metal transport by P(1B)-type ATPases. CURRENT TOPICS IN MEMBRANES 2012; 69:113-36. [PMID: 23046649 DOI: 10.1016/b978-0-12-394390-3.00005-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The P(1B) family of P-type ATPases couples the transport of cytoplasmic transition metals across biological membranes to the hydrolysis of ATP. These ubiquitous transporters function in maintaining cytoplasmic metal quotas and in the assembly of metalloproteins, and have been classified into subfamilies (P(1B-1)-P(1B-5)) on the basis of their transported substrates (Cu(+), Zn(2+), Cu(2+), and Co(2+)) and signature sequences in their transmembrane segments. In addition, each subgroup presents a characteristic membrane topology and specific regulatory cytoplasmic metal-binding domains. In recent years, significant major aspects of their transport mechanism have been described, including the stoichiometry of transport and the delivery of substrates to transport sites by metallochaperones. Toward understanding their structure, the metal coordination by transport sites has been characterized for Cu(+) and Zn(2+)-ATPases. In addition, atomic resolution structures have been determined, providing key insight into the elements that enable transition metal transport. Because the Cu(+)-transporting ATPases are found in humans and are linked to disease, this subfamily has been the focus of intense study. As a result, significant progress has been made toward understanding Cu(+)-ATPase function on the molecular level, using both the human proteins and the bacterial homologs, most notably the CopA proteins from Archaeoglobus fulgidus, Bacillus subtilis, and Thermotoga maritima. This chapter thus focuses on the mechanistic and structural information obtained by studying these latter Cu(+)-ATPases, with some consideration of how these aspects might differ for the other subfamilies of P(1B)-ATPases.
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Affiliation(s)
- Amy C Rosenzweig
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA.
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23
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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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24
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Dmitriev OY. Mechanism of tumor resistance to cisplatin mediated by the copper transporter ATP7B. Biochem Cell Biol 2011; 89:138-47. [PMID: 21455266 DOI: 10.1139/o10-150] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The Wilson disease protein (ATP7B) is a copper-transporting ATPase that is responsible for regulating copper homeostasis in human tissues. ATP7B is associated with cancer resistance to cisplatin, one of the most widely used anticancer drugs. This minireview discusses the possible mechanisms of tumor resistance to cisplatin mediated by ATP7B. Cisplatin binds to the N-terminal cytosolic domain of ATP7B, which contains multiple copper-binding sites. Active platinum efflux catalyzed by ATP7B is unlikely to significantly contribute to cisplatin resistance in vivo. Transient platinum sequestration in the metal-binding domain followed by transfer to an acceptor protein or a low molecular weight compound is proposed as an alternative mechanism of cisplatin detoxification in the cell.
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Affiliation(s)
- Oleg Y Dmitriev
- Department of Biochemistry, University of Saskatchewan, SK, Canada.
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25
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Inesi G. Calcium and copper transport ATPases: analogies and diversities in transduction and signaling mechanisms. J Cell Commun Signal 2011; 5:227-37. [PMID: 21656155 PMCID: PMC3145875 DOI: 10.1007/s12079-011-0136-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 04/28/2011] [Indexed: 12/17/2022] Open
Abstract
The calcium transport ATPase and the copper transport ATPase are members of the P-ATPase family and retain an analogous catalytic mechanism for ATP utilization, including intermediate phosphoryl transfer to a conserved aspartyl residue, vectorial displacement of bound cation, and final hydrolytic cleavage of Pi. Both ATPases undergo protein conformational changes concomitant with catalytic events. Yet, the two ATPases are prototypes of different features with regard to transduction and signaling mechanisms. The calcium ATPase resides stably on membranes delimiting cellular compartments, acquires free Ca2+ with high affinity on one side of the membrane, and releases the bound Ca2+ on the other side of the membrane to yield a high free Ca2+ gradient. These features are a basic requirement for cellular Ca2+ signaling mechanisms. On the other hand, the copper ATPase acquires copper through exchange with donor proteins, and undergoes intracellular trafficking to deliver copper to acceptor proteins. In addition to the cation transport site and the conserved aspartate undergoing catalytic phosphorylation, the copper ATPase has copper binding regulatory sites on a unique N-terminal protein extension, and has also serine residues undergoing kinase assisted phosphorylation. These additional features are involved in the mechanism of copper ATPase intracellular trafficking which is required to deliver copper to plasma membranes for extrusion, and to the trans-Golgi network for incorporation into metalloproteins. Isoform specific glyocosylation contributes to stabilization of ATP7A copper ATPase in plasma membranes.
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Affiliation(s)
- Giuseppe Inesi
- California Pacific Medical Center Research Institute, 475 Brannan Street, San Francisco, CA, 94107, USA,
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Cellular copper levels determine the phenotype of the Arg875 variant of ATP7B/Wilson disease protein. Proc Natl Acad Sci U S A 2011; 108:5390-5. [PMID: 21406592 DOI: 10.1073/pnas.1014959108] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
In human disorders, the genotype-phenotype relationships are often complex and influenced by genetic and/or environmental factors. Wilson disease (WD) is a monogenic disorder caused by mutations in the copper-transporting P-type ATPase ATP7B. WD shows significant phenotypic diversity even in patients carrying identical mutations; the basis for such diverse manifestations is unknown. We demonstrate that the 2623A/G polymorphism (producing the Gly(875) → Arg substitution in the A-domain of ATP7B) drastically alters the intracellular properties of ATP7B, whereas copper reverses the effects. Under basal conditions, the common Gly(875) variant of ATP7B is targeted to the trans-Golgi network (TGN) and transports copper into the TGN lumen. In contrast, the Arg(875) variant is located in the endoplasmic reticulum (ER) and does not deliver copper to the TGN. Elevated copper corrects the ATP7B-Arg(875) phenotype. Addition of only 0.5-5 μM copper triggers the exit of ATP7B-Arg(875) from the ER and restores copper delivery to the TGN. Analysis of the recombinant A-domains by NMR suggests that the ER retention of ATP7B-Arg(875) is attributable to increased unfolding of the Arg(875)-containing A-domain. Copper is not required for the folding of ATP7B-Arg(875) during biosynthesis, but it stabilizes protein and stimulates its activity. A chemotherapeutical drug, cisplatin, that mimics a copper-bound state of ATP7B also corrects the "disease-like" phenotype of ATP7B-Arg(875) and promotes its TGN targeting and transport function. We conclude that in populations harboring the Arg(875) polymorphism, the levels of bioavailable copper may play a vital role in the manifestations of WD.
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Desai V, Donsante A, Swoboda KJ, Martensen M, Thompson J, Kaler SG. Favorably skewed X-inactivation accounts for neurological sparing in female carriers of Menkes disease. Clin Genet 2011; 79:176-82. [PMID: 20497190 DOI: 10.1111/j.1399-0004.2010.01451.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Classical Menkes disease is an X-linked recessive neurodegenerative disorder caused by mutations in ATP7A, which is located at Xq13.1-q21. ATP7A encodes a copper-transporting P-type ATPase and plays a critical role in development of the central nervous system. With rare exceptions involving sex chromosome aneuploidy or X-autosome translocations, female carriers of ATP7A mutations are asymptomatic except for subtle hair and skin abnormalities, although the mechanism for this neurological sparing has not been reported. We studied a three-generation family in which a severe ATP7A mutation, a 5.5-kb genomic deletion spanning exons 13 and 14, segregated. The deletion junction fragment was amplified from the proband by long-range polymerase chain reaction and sequenced to characterize the breakpoints. We screened at-risk females in the family for this junction fragment and analyzed their X-inactivation patterns using the human androgen-receptor (HUMARA) gene methylation assay. We detected the junction fragment in the proband, two obligate heterozygotes, and four of six at-risk females. Skewed inactivation of the X chromosome harboring the deletion was noted in all female carriers of the deletion (n = 6), whereas random X-inactivation was observed in all non-carriers (n = 2). Our results formally document one mechanism for neurological sparing in female carriers of ATP7A mutations. Based on review of X-inactivation patterns in female carriers of other X-linked recessive diseases, our findings imply that substantial expression of a mutant ATP7A at the expense of the normal allele could be associated with neurologic symptoms in female carriers of Menkes disease and its allelic variants, occipital horn syndrome, and ATP7A-related distal motor neuropathy.
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Affiliation(s)
- V Desai
- Unit on Human Copper Metabolism, Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1832, USA
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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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