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Chaturvedi A, Sharma S, Shukla R. Nano-Mediated Molecular Targeting in Diagnosis and Mitigation of Wilson Disease. Mol Neurobiol 2024; 61:4240-4258. [PMID: 38066399 DOI: 10.1007/s12035-023-03816-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 11/18/2023] [Indexed: 07/11/2024]
Abstract
Wilson disease, a rare genetic disorder resulting from mutations in the ATP7B gene disrupts copper metabolism, leading to its harmful accumulation in hepatocytes, the brain, and other organs. It affects roughly 1 in 30,000 individuals, with 1 in 90 being gene carriers. Beyond gene mutations, the disease involves complex factors contributing to copper imbalance. Ongoing research seeks to unravel intricate molecular pathways, offering fresh insights into the disease's mechanisms. Simultaneously, there is a dedicated effort to develop effective therapeutic strategies. Nanotechnology-driven formulations are showing promise for both treatment and early diagnosis of Wilson disease. This comprehensive review covers the entire spectrum of the condition, encompassing pathophysiology, potential biomarkers, established and emerging therapies, ongoing clinical trials, and innovative nanotechnology applications. This multifaceted approach holds the potential to improve our understanding, diagnosis, and management of Wilson's disease, which remains a challenging and potentially life-threatening disorder.
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Affiliation(s)
- Akanksha Chaturvedi
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research-Raebareli (NIPER-Raebareli), Bijnor-Sisendi Road, Sarojini Nagar, Near CRPF Base Camp, Lucknow, UP, 226002, India
| | - Swapnil Sharma
- Department of Pharmacy, Banasthali University, Banasthali, Rajasthan, 304022, India
| | - Rahul Shukla
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research-Raebareli (NIPER-Raebareli), Bijnor-Sisendi Road, Sarojini Nagar, Near CRPF Base Camp, Lucknow, UP, 226002, India.
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2
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Dolgova N, Uhlemann EME, Boniecki MT, Vizeacoumar FS, Ara A, Nouri P, Ralle M, Tonelli M, Abbas SA, Patry J, Elhasasna H, Freywald A, Vizeacoumar FJ, Dmitriev OY. MEMO1 binds iron and modulates iron homeostasis in cancer cells. eLife 2024; 13:e86354. [PMID: 38640016 PMCID: PMC11081632 DOI: 10.7554/elife.86354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 04/15/2024] [Indexed: 04/20/2024] Open
Abstract
Mediator of ERBB2-driven cell motility 1 (MEMO1) is an evolutionary conserved protein implicated in many biological processes; however, its primary molecular function remains unknown. Importantly, MEMO1 is overexpressed in many types of cancer and was shown to modulate breast cancer metastasis through altered cell motility. To better understand the function of MEMO1 in cancer cells, we analyzed genetic interactions of MEMO1 using gene essentiality data from 1028 cancer cell lines and found multiple iron-related genes exhibiting genetic relationships with MEMO1. We experimentally confirmed several interactions between MEMO1 and iron-related proteins in living cells, most notably, transferrin receptor 2 (TFR2), mitoferrin-2 (SLC25A28), and the global iron response regulator IRP1 (ACO1). These interactions indicate that cells with high-MEMO1 expression levels are hypersensitive to the disruptions in iron distribution. Our data also indicate that MEMO1 is involved in ferroptosis and is linked to iron supply to mitochondria. We have found that purified MEMO1 binds iron with high affinity under redox conditions mimicking intracellular environment and solved MEMO1 structures in complex with iron and copper. Our work reveals that the iron coordination mode in MEMO1 is very similar to that of iron-containing extradiol dioxygenases, which also display a similar structural fold. We conclude that MEMO1 is an iron-binding protein that modulates iron homeostasis in cancer cells.
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Affiliation(s)
- Natalia Dolgova
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
| | - Eva-Maria E Uhlemann
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
| | - Michal T Boniecki
- Protein Characterization and Crystallization Facility, University of SaskatchewanSaskatoonCanada
| | | | - Anjuman Ara
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
| | - Paria Nouri
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
| | - Martina Ralle
- Department of Molecular and Medical Genetics, Oregon Health and Sciences UniversityPortlandUnited States
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison (NMRFAM), University of WisconsinMadisonUnited States
| | - Syed A Abbas
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
| | - Jaala Patry
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
| | - Hussain Elhasasna
- Department of Pathology and Laboratory Medicine, University of SaskatchewanSaskatoonCanada
| | - Andrew Freywald
- Department of Pathology and Laboratory Medicine, University of SaskatchewanSaskatoonCanada
| | - Franco J Vizeacoumar
- Cancer Research Department, Saskatchewan Cancer AgencySaskatoonCanada
- Division of Oncology, University of SaskatchewanSaskatoonCanada
| | - Oleg Y Dmitriev
- Department of Biochemistry, Microbiology and Immunology, University of SaskatchewanSaskatoonCanada
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3
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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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4
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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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5
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Shankar Singh R, Bhadra Arna A, Dong H, Yadav M, Aggarwal A, Wu Y. Structure-function analysis of DEAD-box helicase DDX43. Methods 2022; 204:286-299. [DOI: 10.1016/j.ymeth.2022.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/15/2022] [Accepted: 03/02/2022] [Indexed: 01/21/2023] Open
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Uhlemann EME, Lee W, Tonelli M, Dmitriev OY. At sixes and sevens: cryptic domain in the metal binding chain of the human copper transporter ATP7A. Biophys J 2021; 120:4600-4607. [PMID: 34461106 DOI: 10.1016/j.bpj.2021.08.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/27/2021] [Accepted: 08/25/2021] [Indexed: 10/20/2022] Open
Abstract
ATP7A and ATP7B are structurally similar but functionally distinct active copper transporters that regulate copper levels in the human cells and deliver copper to the biosynthetic pathways. Both proteins have a chain of six cytosolic metal-binding domains (MBDs) believed to be involved in the copper-dependent regulation of the activity and intracellular localization of these enzymes. Although all the MBDs are quite similar in structure, their spacing differs markedly between ATP7A and ATP7B. We show by NMR that the long polypeptide between MBD1 and MBD2 of ATP7A forms an additional seventh metastable domain, which we called HMA1A (heavy metal associated domain 1A). The structure of HMA1A resembles the MBDs but contains no copper-binding site. The HMA1A domain, which is unique to ATP7A, may modulate regulatory interactions between MBD1-3, contributing to the distinct functional properties of ATP7A and ATP7B.
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Affiliation(s)
- Eva-Maria E Uhlemann
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Woonghee Lee
- Department of Chemistry, University of Colorado, Denver, Colorado
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison, University of Wisconsin, Madison, Wisconsin
| | - Oleg Y Dmitriev
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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Yadav M, Singh RS, Hogan D, Vidhyasagar V, Yang S, Chung IYW, Kusalik A, Dmitriev OY, Cygler M, Wu Y. The KH domain facilitates the substrate specificity and unwinding processivity of DDX43 helicase. J Biol Chem 2021; 296:100085. [PMID: 33199368 PMCID: PMC7949032 DOI: 10.1074/jbc.ra120.015824] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/03/2020] [Accepted: 11/16/2020] [Indexed: 01/21/2023] Open
Abstract
The K-homology (KH) domain is a nucleic acid-binding domain present in many proteins. Recently, we found that the DEAD-box helicase DDX43 contains a KH domain in its N-terminus; however, its function remains unknown. Here, we purified recombinant DDX43 KH domain protein and found that it prefers binding ssDNA and ssRNA. Electrophoretic mobility shift assay and NMR revealed that the KH domain favors pyrimidines over purines. Mutational analysis showed that the GXXG loop in the KH domain is involved in pyrimidine binding. Moreover, we found that an alanine residue adjacent to the GXXG loop is critical for binding. Systematic evolution of ligands by exponential enrichment, chromatin immunoprecipitation-seq, and cross-linking immunoprecipitation-seq showed that the KH domain binds C-/T-rich DNA and U-rich RNA. Bioinformatics analysis suggested that the KH domain prefers to bind promoters. Using 15N-heteronuclear single quantum coherence NMR, the optimal binding sequence was identified as TTGT. Finally, we found that the full-length DDX43 helicase prefers DNA or RNA substrates with TTGT or UUGU single-stranded tails and that the KH domain is critically important for sequence specificity and unwinding processivity. Collectively, our results demonstrated that the KH domain facilitates the substrate specificity and processivity of the DDX43 helicase.
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Affiliation(s)
- Manisha Yadav
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Ravi Shankar Singh
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Daniel Hogan
- Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | | | - Shizhuo Yang
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Ivy Yeuk Wah Chung
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Anthony Kusalik
- Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Oleg Y Dmitriev
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Miroslaw Cygler
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Yuliang Wu
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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8
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Roy S, McCann CJ, Ralle M, Ray K, Ray J, Lutsenko S, Jayakanthan S. Analysis of Wilson disease mutations revealed that interactions between different ATP7B mutants modify their properties. Sci Rep 2020; 10:13487. [PMID: 32778786 PMCID: PMC7418023 DOI: 10.1038/s41598-020-70366-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 06/16/2020] [Indexed: 01/05/2023] Open
Abstract
Wilson disease (WD) is an autosomal-recessive disorder caused by mutations in the copper (Cu)-transporter ATP7B. Thus far, studies of WD mutations have been limited to analysis of ATP7B mutants in the homozygous states. However, the majority of WD patients are compound-heterozygous, and how different mutations on two alleles impact ATP7B properties is unclear. We characterized five mutations identified in Indian WD patients, first by expressing each alone and then by co-expressing two mutants with dissimilar properties. Mutations located in the regulatory domains of ATP7B-A595T, S1362A, and S1426I-do not affect ATP7B targeting to the trans-Golgi network (TGN) but reduce its Cu-transport activity. The S1362A mutation also inhibits Cu-dependent trafficking from the TGN. The G1061E and G1101R mutations, which are located within the ATP-binding domain, cause ATP7B retention in the endoplasmic reticulum, inhibit Cu-transport, and lower ATP7B protein abundance. Co-expression of the A595T and G1061E mutations, which mimics the compound-heterozygous state of some WD patients, revealed an interaction between these mutants that altered their intracellular localization and trafficking under both low and high Cu conditions. These findings highlight the need to study WD variants in both the homozygous and compound-heterozygous states to better understand the genotype-phenotype correlations and incomplete penetrance observed in WD.
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Affiliation(s)
- Shubhrajit Roy
- Department of Physiology, Johns Hopkins Medical Institute, Baltimore, MD, USA. .,S. N. Pradhan Centre for Neurosciences, University of Calcutta, Kolkata, India.
| | - Courtney J McCann
- Department of Physiology, Johns Hopkins Medical Institute, Baltimore, MD, USA
| | - Martina Ralle
- Oregon Health and Science University, Portland, OR, USA
| | - Kunal Ray
- ATGC Diagnostics Private Ltd, Kolkata, India
| | - Jharna Ray
- S. N. Pradhan Centre for Neurosciences, University of Calcutta, Kolkata, India
| | - Svetlana Lutsenko
- Department of Physiology, Johns Hopkins Medical Institute, Baltimore, MD, USA.
| | - Samuel Jayakanthan
- Department of Physiology, Johns Hopkins Medical Institute, Baltimore, MD, USA
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Tang N, Sandahl TD, Ott P, Kepp KP. Computing the Pathogenicity of Wilson's Disease ATP7B Mutations: Implications for Disease Prevalence. J Chem Inf Model 2019; 59:5230-5243. [PMID: 31751128 DOI: 10.1021/acs.jcim.9b00852] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Genetic variations in the gene encoding the copper-transport protein ATP7B are the primary cause of Wilson's disease. Controversially, clinical prevalence seems much smaller than the prevalence estimated by genetic screening tools, causing fear that many people are undiagnosed, although early diagnosis and treatment is essential. To address this issue, we benchmarked 16 state-of-the-art computational disease-prediction methods against established data of missense ATP7B mutations. Our results show that the quality of the methods varies widely. We show the importance of optimizing the threshold of the methods used to distinguish pathogenic from nonpathogenic mutations against data of clinically confirmed pathogenic and nonpathogenic mutations. We find that most methods use thresholds that predict too many ATP7B mutations to be pathogenic. Thus, our findings explain the current controversy on Wilson's disease prevalence because meta-analysis and text search methods include many computational estimates that lead to higher disease prevalence than clinically observed. As proteins and diseases differ widely, a one-size-fits-all threshold cannot distinguish pathogenic and nonpathogenic mutations efficiently, as shown here. We also show that amino acid changes with small evolutionary substitution probability, mainly due to amino acid volume, are more associated with the disease, implying a pathological effect on the conformational state of the protein, which could affect copper transport or adenosine triphosphate recognition and hydrolysis. These findings may be a first step toward a more quantitative genotype-phenotype relationship of Wilson's disease.
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Affiliation(s)
- Ning Tang
- DTU Chemistry , Technical University of Denmark , Kemitorvet 206 , 2800 Kongens Lyngby , Denmark
| | - Thomas D Sandahl
- Department of Hepatology and Gastroenterology , Aarhus University Hospital , 8200 Aarhus , Denmark
| | - Peter Ott
- Department of Hepatology and Gastroenterology , Aarhus University Hospital , 8200 Aarhus , Denmark
| | - Kasper P Kepp
- DTU Chemistry , Technical University of Denmark , Kemitorvet 206 , 2800 Kongens Lyngby , Denmark
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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: 50] [Impact Index Per Article: 10.0] [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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Ilyechova EY, Miliukhina IV, Karpenko MN, Orlov IA, Puchkova LV, Samsonov SA. Case of Early-Onset Parkinson's Disease in a Heterozygous Mutation Carrier of the ATP7B Gene. J Pers Med 2019; 9:jpm9030041. [PMID: 31426520 PMCID: PMC6789574 DOI: 10.3390/jpm9030041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/10/2019] [Accepted: 08/13/2019] [Indexed: 02/04/2023] Open
Abstract
In this paper, we report a clinically proven case of Parkinson’s disease (PD) with early onset in a patient who is a heterozygous mutation carrier of ATP7B (the Wilson’s disease gene). The patient was observed from 2011 to 2018 in the Center for Neurodegenerative Diseases, Institute of Experimental Medicine (St. Petersburg, Russia). During this period, the patient displayed aggravation of PD clinical symptoms that were accompanied by a decrease in the ceruloplasmin concentration (from 0.33 to 0.27 g/L) and an increase in serum nonceruloplasmin copper, which are typical of the late stages of Wilson’s disease. It was found that one of the alleles of exon 14 in the ATP7B gene, which partially codes of the nucleotide-binding domain (N-domain), carries a mutation not previously reported corresponding to Cys1079Gly substitution. Alignment of the ATP7B N-domain amino acid sequences of representative vertebrate species has shown that the Cys at 1079 position is conserved throughout the evolution. Molecular dynamic analysis of a polypeptide with Cys1079Gly substitution showed that the mutation causes profound conformational changes in the N-domain, which could potentially lead to impairment of its functions. The role of ATP7B gene mutations in PD development is discussed.
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Affiliation(s)
- Ekaterina Y Ilyechova
- International Research Laboratory of Trace Elements Metabolism, ITMO University, Kronverksky av., 49, St. Petersburg 197101, Russia
- Department of Molecular Genetics, Institute of Experimental Medicine, Pavlov str., 12, St. Petersburg 197376, Russia
- Biophysics Department, Peter the Great St. Petersburg Polytechnic University, Politehknicheskay str., 29, St. Petersburg 195251, Russia
| | - Irina V Miliukhina
- Centre for Neurodegenerative diseases, Institute of Experimental Medicine, Maluy av., Petrogradskiy district, 13, St. Petersburg 197198, Russia
| | - Marina N Karpenko
- Department of Physiology, Institute of Experimental Medicine, Pavlov str., 12, St. Petersburg 197376, Russia
| | - Iurii A Orlov
- International Research Laboratory of Trace Elements Metabolism, ITMO University, Kronverksky av., 49, St. Petersburg 197101, Russia
| | - Ludmila V Puchkova
- International Research Laboratory of Trace Elements Metabolism, ITMO University, Kronverksky av., 49, St. Petersburg 197101, Russia.
- Department of Molecular Genetics, Institute of Experimental Medicine, Pavlov str., 12, St. Petersburg 197376, Russia.
- Biophysics Department, Peter the Great St. Petersburg Polytechnic University, Politehknicheskay str., 29, St. Petersburg 195251, Russia.
| | - Sergey A Samsonov
- International Research Laboratory of Trace Elements Metabolism, ITMO University, Kronverksky av., 49, St. Petersburg 197101, Russia
- Faculty of Chemistry, University of Gdańsk, Wita Stwosza str., 63, 80-308 Gdańsk, Poland
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13
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Copper regulates rest-activity cycles through the locus coeruleus-norepinephrine system. Nat Chem Biol 2018; 14:655-663. [PMID: 29867144 PMCID: PMC6008210 DOI: 10.1038/s41589-018-0062-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/19/2018] [Indexed: 12/21/2022]
Abstract
The unusually high demand for metals in the brain along with insufficient understanding of how their dysregulation contributes to neurological diseases motivates the study of how inorganic chemistry influences neural circuitry. We now report that the transition metal copper is essential for regulating rest–activity cycles and arousal. Copper imaging and gene expression analysis in zebrafish identifies the locus coeruleus-norepinephrine (LC-NE) system, a vertebrate-specific neuromodulatory circuit critical for regulating sleep, arousal, attention, memory and emotion, as a copper-enriched unit with high levels of copper transporters CTR1 and ATP7A and the copper enzyme dopamine beta-hydroxylase (DBH) that produces NE. Copper deficiency induced by genetic disruption of ATP7A, which loads copper into DBH, lowers NE levels and hinders LC function as manifested by disruption in rest–activity modulation. Moreover, LC dysfunction caused by copper deficiency from ATP7A disruption can be rescued by restoring synaptic levels of NE, establishing a molecular CTR1-ATP7A-DBH-NE axis for copper-dependent LC function.
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Gupta A, Das S, Ray K. A glimpse into the regulation of the Wilson disease protein, ATP7B, sheds light on the complexity of mammalian apical trafficking pathways. Metallomics 2018; 10:378-387. [PMID: 29473088 DOI: 10.1039/c7mt00314e] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Wilson disease (WD), a Mendelian disorder of copper metabolism caused by mutations in the ATP7B gene, manifests a large spectrum of phenotypic variability. This phenomenon of extensive symptom variation is not frequently associated with a monogenic disorder. We hypothesize that the phenotypic variability in WD is primarily driven by the variations in interacting proteins that regulate the ATP7B function and localization in the cell. Based on existing literature, we delineated a potential molecular mechanism for ATP7B mediated copper transport in the milieu of its interactome, its dysfunction in WD and the resulting variability in the phenotypic manifestation. Understanding the copper-induced apical trafficking of ATP7B also significantly contributes to the appreciation of the complexities of the ligand-induced transport pathway. We believe that this holistic view of WD will pave the way for a better opportunity for rational drug design and therapeutics.
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Affiliation(s)
- Arnab Gupta
- Department of Biological Sciences, Indian Institute of Science Education and Research - Kolkata (IISER K), Mohanpur 741246, West Bengal, India.
| | - Santanu Das
- Department of Biological Sciences, Indian Institute of Science Education and Research - Kolkata (IISER K), Mohanpur 741246, West Bengal, India.
| | - Kunal Ray
- Academy of Scientific & Innovative Research (AcSIR), CSIR - HRDC Campus, Ghaziabad, Uttar Pradesh - 201002, India
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The Structure of Metal Binding Domain 1 of the Copper Transporter ATP7B Reveals Mechanism of a Singular Wilson Disease Mutation. Sci Rep 2018; 8:581. [PMID: 29330485 PMCID: PMC5766562 DOI: 10.1038/s41598-017-18951-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/20/2017] [Indexed: 12/12/2022] Open
Abstract
Copper-transporter ATP7B maintains copper homeostasis in the human cells and delivers copper to the biosynthetic pathways for incorporation into the newly synthesized copper-containing proteins. ATP7B is a target of several hundred mutations that lead to Wilson disease, a chronic copper toxicosis. ATP7B contains a chain of six cytosolic metal-binding domains (MBDs), the first four of which (MBD1-4) are believed to be regulatory, and the last two (MBD5-6) are required for enzyme activity. We report the NMR structure of MBD1, the last unsolved metal-binding domain of ATP7B. The structure reveals the disruptive mechanism of G85V mutation, one of the very few disease causing missense mutations in the MBD1-4 region of ATP7B.
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16
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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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17
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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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18
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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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19
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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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20
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Mayerhofer H, Sautron E, Rolland N, Catty P, Seigneurin-Berny D, Pebay-Peyroula E, Ravaud S. Structural Insights into the Nucleotide-Binding Domains of the P1B-type ATPases HMA6 and HMA8 from Arabidopsis thaliana. PLoS One 2016; 11:e0165666. [PMID: 27802305 PMCID: PMC5089723 DOI: 10.1371/journal.pone.0165666] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 10/14/2016] [Indexed: 01/24/2023] Open
Abstract
Copper is a crucial ion in cells, but needs to be closely controlled due to its toxic potential and ability to catalyse the formation of radicals. In chloroplasts, an important step for the proper functioning of the photosynthetic electron transfer chain is the delivery of copper to plastocyanin in the thylakoid lumen. The main route for copper transport to the thylakoid lumen is driven by two PIB-type ATPases, Heavy Metal ATPase 6 (HMA6) and HMA8, located in the inner membrane of the chloroplast envelope and in the thylakoid membrane, respectively. Here, the crystal structures of the nucleotide binding domain of HMA6 and HMA8 from Arabidopsis thaliana are reported at 1.5Å and 1.75Å resolution, respectively, providing the first structural information on plants Cu+-ATPases. The structures reveal a compact domain, with two short helices on both sides of a twisted beta-sheet. A double mutant, aiding in the crystallization, provides a new crystal contact, but also avoids an internal clash highlighting the benefits of construct modifications. Finally, the histidine in the HP motif of the isolated domains, unable to bind ATP, shows a side chain conformation distinct from nucleotide bound structures.
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Affiliation(s)
- Hubert Mayerhofer
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Emeline Sautron
- Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Institut de Biosciences et Biotechnologies de Grenoble (BIG), Université Grenoble Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Norbert Rolland
- Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Institut de Biosciences et Biotechnologies de Grenoble (BIG), Université Grenoble Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Patrice Catty
- Laboratoire de Chimie et Biologie des Métaux (LCBM), BIG, Université Grenoble Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Daphné Seigneurin-Berny
- Laboratoire de Physiologie Cellulaire et Végétale (LPCV), Institut de Biosciences et Biotechnologies de Grenoble (BIG), Université Grenoble Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Eva Pebay-Peyroula
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Stéphanie Ravaud
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France
- * E-mail:
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21
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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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22
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Meng D, Bruschweiler-Li L, Zhang F, Brüschweiler R. Modulation and Functional Role of the Orientations of the N- and P-Domains of Cu+-Transporting ATPase along the Ion Transport Cycle. Biochemistry 2015. [DOI: 10.1021/acs.biochem.5b00420] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Dan Meng
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Lei Bruschweiler-Li
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Fengli Zhang
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Rafael Brüschweiler
- Department of Chemistry & Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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23
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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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24
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Xie P, Hao X, Herzberg M, Luo Y, Nies DH, Wei G. Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China. J Environ Sci (China) 2015; 27:179-187. [PMID: 25597676 DOI: 10.1016/j.jes.2014.07.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 06/11/2014] [Accepted: 07/31/2014] [Indexed: 06/04/2023]
Abstract
To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB). It shows that: Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF (Cation Diffusion Facilitator), HupE/UreJ and CHR (chromate ion transporter) family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter, assisted with putative CzcD, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion, indicating a potential in-site phytoremediation usage in the mining tailing regions of China.
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Affiliation(s)
- Pin Xie
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China; Molecular Microbiology, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), 06120, Germany.
| | - Xiuli Hao
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Martin Herzberg
- Molecular Microbiology, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Yantao Luo
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Dietrich H Nies
- Molecular Microbiology, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Gehong Wei
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
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25
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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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26
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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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27
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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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28
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Przybyłkowski A, Gromadzka G, Wawer A, Grygorowicz T, Cybulska A, Członkowska A. Intestinal expression of metal transporters in Wilson's disease. Biometals 2013; 26:925-34. [PMID: 23963605 PMCID: PMC3825560 DOI: 10.1007/s10534-013-9668-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 08/09/2013] [Indexed: 11/30/2022]
Abstract
In Wilson’s disease (WND), biallelic ATP7B gene mutation is responsible for pathological copper accumulation in the liver, brain and other organs. It has been proposed that copper transporter 1 (CTR1) and the divalent metal transporter 1 (DMT1) translocate copper across the human intestinal epithelium, while Cu-ATPases: ATP7A and ATP7B serve as copper efflux pumps. In this study, we investigated the expression of CTR1, DMT1 and ATP7A in the intestines of both WND patients and healthy controls to examine whether any adaptive mechanisms to systemic copper overload function in the enterocytes. Duodenal biopsy samples were taken from 108 patients with Wilson’s disease and from 90 controls. CTR1, DMT1, ATP7A and ATP7B expression was assessed by polymerase chain reaction and Western blot. Duodenal CTR1 mRNA and protein expression was decreased in WND patients in comparison to control subjects, while ATP7A mRNA and protein production was increased. The variable expression of copper transporters may serve as a defense mechanism against systemic copper overload resulting from functional impairment of ATP7B.
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Affiliation(s)
- Adam Przybyłkowski
- Department of Clinical and Experimental Pharmacology, Medical University of Warsaw, ul. Krakowskie Przedmieście 26/28, 00-927, Warsaw, Poland,
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29
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Cakic M, Mitic Z, Nikolic G, Savic I, Savic IM. Design and optimization of drugs used to treat copper deficiency. Expert Opin Drug Discov 2013; 8:1253-63. [PMID: 23919882 DOI: 10.1517/17460441.2013.825245] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Copper is an essential element in the human organism. Furthermore, copper deficiency is rare; however, the hematologic manifestations associated with copper deficiency, such as anemia, leukopenia, neutropenia, myeloneuropathy and osteoporosis, are well known. AREAS COVERED The authors present an overview of the various commercially available drugs used in the treatment of copper deficiency. Furthermore, the authors offer a description of copper complexes, as potential pharmaceutically active compounds, that can be used in the design of new formulations with therapeutic potential. EXPERT OPINION Progress in the synthesis of new metallo-organic complexes (such as the copper-pullulan complex) and the chelated form of copper have provided new avenues for drug design that combat copper deficiency. The copper-pullulan complex, as an active compound, has been designed in its solid dosage form, and its optimization in the treatment of copper deficiency has been furthered through advancements in experimental design methodology. The authors believe that the numerous ongoing studies, evaluating the synthesis of these complexes, should produce new additions to the copper deficiency therapeutic armamentarium in the future.
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Affiliation(s)
- Milorad Cakic
- University of Nis, Faculty of Technology, Department of Pharmaceutics , Bulevar oslobodjenja 124, 16000 Leskovac , Serbia +381 16 242859 ; +381 16 242859 ;
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Squitti R, Polimanti R, Bucossi S, Ventriglia M, Mariani S, Manfellotto D, Vernieri F, Cassetta E, Ursini F, Rossini PM. Linkage disequilibrium and haplotype analysis of the ATP7B gene in Alzheimer's disease. Rejuvenation Res 2013; 16:3-10. [PMID: 22950421 DOI: 10.1089/rej.2012.1357] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Copper dyshomeostasis leading to a labile Cu(2+) not bound to ceruloplasmin ("free" copper) may influence Alzheimer's disease (AD) onset or progression. To investigate this hypothesis, we investigated ATP7B, the gene that controls copper excretion through the bile and concentrations of free copper in systemic circulation. Our study analyzed informative ATP7B single-nucleotide polymorphisms (SNPs) in a case-control population (n=515). In particular, we evaluated the genetic structure of the ATP7B gene using the HapMap database and carried out a genetic association investigation. Linkage disequilibrium (LD) analysis highlighted that our informative SNPs and their LD SNPs covered 96% of the ATP7B gene sequence, distinguishing two "strong LD" blocks. The first LD block contains the gene region encoding for transmembrane and copper-binding, whereas the second LD block encodes for copper-binding domains. The genetic association analysis showed significant results after multiple testing correction for all investigated variants (rs1801243, odds ratio [OR]=1.52, 95% confidence interval [CI]=1.10-2.09, p=0.010; rs2147363, OR=1.58, 95% CI=1.11-2.25, p=0.010; rs1061472, OR=1.73, 95% CI=1.23-2.43, p=0.002; rs732774, OR=2.31, 95% CI=1.41-3.77, p<0.001), indicating that SNPs in transmembrane domains may have a stronger association with AD risk than variants in copper-binding domains. Our study provides novel insights that confirm the role of ATP7B as a potential genetic risk factor for AD. The analysis of ATP7B informative SNPs confirms our previous hypothesis about the absence of ATP7B in the significant loci of genome-wide association studies of AD and the genetic association study suggests that transmembrane and adenosine triphosphate (ATP) domains in the ATP7B gene may harbor variants/haplotypes associated with AD risk.
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Affiliation(s)
- Rosanna Squitti
- Department of Neurology, Campus Bio-Medico University, Rome, Italy
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31
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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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32
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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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33
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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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34
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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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35
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O'Grady C, Rempel BL, Sokaribo A, Nokhrin S, Dmitriev OY. One-step amino acid selective isotope labeling of proteins in prototrophic Escherichia coli strains. Anal Biochem 2012; 426:126-8. [PMID: 22538396 DOI: 10.1016/j.ab.2012.04.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 04/10/2012] [Accepted: 04/13/2012] [Indexed: 01/27/2023]
Abstract
Amino acid selective isotope labeling is a useful approach to simplification of nuclear magnetic resonance (NMR) spectra of large proteins. Cell-free protein synthesis offers essentially unlimited flexibility of labeling patterns but is labor-intensive and expensive. In vivo labeling is simple in principle but generally requires auxotrophic strains, inhibitors of amino acid synthesis, or complex media formulations. We describe a simple procedure for amino acid selective labeling of proteins expressed in prototrophic Escherichia coli strains. Excellent labeling selectivity was achieved for histidine, lysine, methionine, and alanine. Simplicity and robustness of this protocol make it a useful tool for protein NMR.
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Affiliation(s)
- Christopher O'Grady
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E5
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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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Greie JC. The KdpFABC complex from Escherichia coli: a chimeric K+ transporter merging ion pumps with ion channels. Eur J Cell Biol 2012; 90:705-10. [PMID: 21684627 DOI: 10.1016/j.ejcb.2011.04.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
The KdpFABC complex represents a multi-subunit ATP-driven potassium pump, which is only found in bacteria and archaea. Based on the properties of the ATP-hydrolyzing subunit (KdpB) the transporter has been classified as a type IA P-type ATPase. However, structural and functional properties of the remaining subunits clearly show homologies to members of the potassium channel as well as the ABC transporter family, thus rendering the KdpFABC complex to represent an inimitable chimera of ion pumps and ion channels. Accordingly, this striking juxtaposition entails special features of KdpFABC with respect to typical members of each of the transporter families, involving not only the concepts but also the structures of ion channels and ion pumps. For example, the sites of ATP hydrolysis and substrate transport are spatially separated on two different polypeptides, which, in turn, leads to a unique coupling mechanism. During catalysis, the KdpFABC complex cycles between two main conformational states, each of which comprises different structural properties together with different binding affinities for both ATP and the transport substrate. These structural configurations have recently been directly visualized in the working enzyme. Translocation of potassium is mediated by the KdpA subunit, which comprises structural as well as functional homologies to potassium channels of the MPM-type. The KdpC subunit participates in the binding of ATP, thus acting as a catalytic chaperone, which increases the ATP binding affinity of the KdpB subunit via a mechanism typical of nucleotide binding in ABC transporters.
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Affiliation(s)
- Jörg-Christian Greie
- University of Osnabrück, Faculty of Biology and Chemistry, Department of Microbiology, Barbarastrasse 11, 49076 Osnabrück, Germany.
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38
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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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39
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Pope CR, Flores AG, Kaplan JH, Unger VM. Structure and function of copper uptake transporters. CURRENT TOPICS IN MEMBRANES 2012; 69:97-112. [PMID: 23046648 DOI: 10.1016/b978-0-12-394390-3.00004-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Owing to their redox and coordination chemistry copper ions play essential roles in cellular function. Research over the past 20 years has shed much light on the biochemistry of copper homeostasis, and the emergence of high-resolution crystal structures for many of the proteins that partake in cellular copper biology have began to provide insight into the molecular mechanisms by which cells handle this important metal. A notable gap in our understanding is related to the process by which cells acquire copper ions. This chapter describes recent progress in the structure determination of cellular copper uptake transporters and how the emerging structural information aids understanding of the molecular mechanisms that govern cellular copper acquisition and distribution.
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Affiliation(s)
- Christopher R Pope
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
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40
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Roberts EA. Using metalloproteomics to investigate the cellular physiology of copper in hepatocytes. Metallomics 2012; 4:633-40. [DOI: 10.1039/c2mt20019h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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41
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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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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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43
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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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44
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Irzik K, Pfrötzschner J, Goss T, Ahnert F, Haupt M, Greie JC. The KdpC subunit of the Escherichia coli K+-transporting KdpB P-type ATPase acts as a catalytic chaperone. FEBS J 2011; 278:3041-53. [PMID: 21711450 DOI: 10.1111/j.1742-4658.2011.08224.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In Bacteria and Archaea, high-affinity potassium uptake is mediated by the ATP-driven KdpFABC complex. On the basis of the biochemical properties of the ATP-hydrolyzing subunit KdpB, the transport complex is classified as type IA P-type ATPase. However, the KdpA subunit, which promotes K(+) transport, clearly resembles a potassium channel, such that the KdpFABC complex represents a chimera of ion pumps and ion channels. In the present study, we demonstrate that the blending of these two groups of transporters in KdpFABC also entails a nucleotide-binding mechanism in which the KdpC subunit acts as a catalytic chaperone. This mechanism is found neither in P-type ATPases nor in ion channels, although parallels are found in ABC transporters. In the latter, the ATP nucleotide is coordinated by the LSGGQ signature motif via double hydrogen bonds at a conserved glutamine residue, which is also present in KdpC. High-affinity nucleotide binding to the KdpFABC complex was dependent on the presence of this conserved glutamine residue in KdpC. In addition, both ATP binding to KdpC and ATP hydrolysis activity of KdpFABC were sensitive to the accessibility, presence or absence of the hydroxyl groups at the ribose moiety of the nucleotide. Furthermore, the KdpC subunit was shown to interact with the nucleotide-binding loop of KdpB in an ATP-dependent manner around the ATP-binding pocket, thereby increasing the ATP-binding affinity by the formation of a transient KdpB/KdpC/ATP ternary complex.
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Affiliation(s)
- Kristina Irzik
- Fachbereich Biologie/Chemie, Universität Osnabrück, Osnabrück, Germany
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45
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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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46
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Affiliation(s)
- Michael G. Palmgren
- Center for Membrane Pumps in Cells and Disease – PUMPKIN, Danish National Research Foundation, University of Copenhagen, DK-1871 Frederiksberg C, Denmark;
| | - Poul Nissen
- Center for Membrane Pumps in Cells and Disease – PUMPKIN, Danish National Research Foundation, Aarhus University, DK-8000 Århus C, Denmark;
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Dmitriev OY, Bhattacharjee A, Nokhrin S, Uhlemann EME, Lutsenko S. Difference in stability of the N-domain underlies distinct intracellular properties of the E1064A and H1069Q mutants of copper-transporting ATPase ATP7B. J Biol Chem 2011; 286:16355-62. [PMID: 21398519 DOI: 10.1074/jbc.m110.198101] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Wilson disease (WD) is a disorder of copper metabolism caused by mutations in the Cu-transporting ATPase ATP7B. WD is characterized by significant phenotypic variability, the molecular basis of which is poorly understood. The E1064A mutation in the N-domain of ATP7B was previously shown to disrupt ATP binding. We have now determined, by NMR, the structure of the N-domain containing this mutation and compared properties of E1064A and H1069Q, another mutant with impaired ATP binding. The E1064A mutation does not change the overall fold of the N-domain. However, the position of the α1,α2-helical hairpin (α-HH) that houses Glu(1064) and His(1069) is altered. The α-HH movement produces a more open structure compared with the wild-type ATP-bound form and misaligns ATP coordinating residues, thus explaining complete loss of ATP binding. In the cell, neither the stability nor targeting of ATP7B-E1064A to the trans-Golgi network differs significantly from the wild type. This is in a contrast to the H1069Q mutation within the same α-HH, which greatly destabilizes protein both in vitro and in cells. The difference between two mutants can be linked to a lower stability of the α-HH in the H1069Q variant at the physiological temperature. We conclude that the structural stability of the N-domain rather than the loss of ATP binding plays a defining role in the ability of ATP7B to reach the trans-Golgi network, thus contributing to phenotypic variability in WD.
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Affiliation(s)
- Oleg Y Dmitriev
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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In silico modeling of the Menkes copper-translocating P-type ATPase 3rd metal binding domain predicts that phosphorylation regulates copper-binding. Biometals 2011; 24:477-87. [DOI: 10.1007/s10534-011-9410-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 01/06/2011] [Indexed: 12/17/2022]
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Pilankatta R, Lewis D, Inesi G. Involvement of protein kinase D in expression and trafficking of ATP7B (copper ATPase). J Biol Chem 2010; 286:7389-96. [PMID: 21189263 DOI: 10.1074/jbc.m110.171454] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
ATP7B is a P-type ATPase involved in copper transport and homeostasis. In experiments with microsomes isolated from COS-1 cells or HepG2 hepatocytes sustaining ATP7B heterologous expression, we found that ATP7B utilization of ATP includes autophosphorylation of an aspartyl residue serving as ATPase catalytic intermediate as well as phosphorylation of serine residues by protein kinase D (PKD). The latter was abolished by specific PKD inhibition with CID755673. The presence of PKD protein in the microsomal fraction was demonstrated by Western blotting. PKD is a serine/threonine kinase that associates with the trans-Golgi network, regulating fission of transport carriers destined to the cell surface. Parallel studies on cultured cells showed that nascent WT ATP7B transits to the Golgi complex where it undergoes serine phosphorylation by PKD. Misfolded ATP7B protein (especially if subjected to deletions) underwent proteasome-mediated degradation, which provides effective quality control. Inhibition of proteasome-mediated degradation with MG132 yielded additional, but nonfunctional protein. On the other hand, serine phosphorylation protected WT ATP7B from degradation. Protection was enhanced by PKD activation with phorbol esters and limited by PKD inhibition with CID75673. As a final step, phosphorylated ATP7B was transferred from the Golgi complex to cytosolic trafficking vesicles. Phosphorylation and trafficking were completely prevented by mutations of critical copper binding sites, demonstrating copper dependence of both PKD-assisted phosphorylation and trafficking. ATP7B trafficking was markedly reduced by the Ser-478/481/1121/1453 to Ala mutation. We conclude that PKD plays a key role in copper-dependent serine phosphorylation, permitting high levels of ATP7B protein expression and trafficking.
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Affiliation(s)
- Rajendra Pilankatta
- California Pacific Medical Center Research Institute, San Francisco, California 94107, USA
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50
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Behari M, Pardasani V. Genetics of Wilsons disease. Parkinsonism Relat Disord 2010; 16:639-44. [PMID: 20708958 DOI: 10.1016/j.parkreldis.2010.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 07/06/2010] [Accepted: 07/07/2010] [Indexed: 02/03/2023]
Abstract
Wilson's disease is a rare autosomal recessive disorder of copper transport due to mutations in the ATP7B gene, responsible for transport of copper into bile from hepatocytes and its incorporation into apoceruloplasmin to form ceruloplasmin resulting in excessive accumulation of copper in the liver and extrahepatic tissues. Clinical features of WD result from toxic accumulation of copper in liver, brain and kidney. Early diagnosis is mandatory to initiate early treatment to prevent morbidity and mortality. More than 400 mutations have been reported, some of which are rather characteristic of geographical regions and ethnic population. Genetic testing is not useful as a routine procedure, but has its role in at risk individuals such as siblings and children of probands and in individuals with suggestive symptoms but where other tests are contradictory.
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Affiliation(s)
- Madhuri Behari
- Department of Neurology, All India Institute of Medical Sciences, New Delhi 110029, India.
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