1
|
Decreased Expression of the Slc31a1 Gene and Cytoplasmic Relocalization of Membrane CTR1 Protein in Renal Epithelial Cells: A Potent Protective Mechanism against Copper Nephrotoxicity in a Mouse Model of Menkes Disease. Int J Mol Sci 2022; 23:ijms231911441. [PMID: 36232742 PMCID: PMC9570402 DOI: 10.3390/ijms231911441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/04/2022] [Accepted: 09/20/2022] [Indexed: 12/02/2022] Open
Abstract
Kidneys play an especial role in copper redistribution in the organism. The epithelial cells of proximal tubules perform the functions of both copper uptake from the primary urine and release to the blood. These cells are equipped on their apical and basal membrane with copper transporters CTR1 and ATP7A. Mosaic mutant mice displaying a functional dysfunction of ATP7A are an established model of Menkes disease. These mice exhibit systemic copper deficiency despite renal copper overload, enhanced by copper therapy, which is indispensable for their life span extension. The aim of this study was to analyze the expression of Slc31a1 and Slc31a2 genes (encoding CTR1/CTR2 proteins) and the cellular localization of the CTR1 protein in suckling, young and adult mosaic mutants. Our results indicate that in the kidney of both intact and copper-injected 14-day-old mutants showing high renal copper content, CTR1 mRNA level is not up-regulated compared to wild-type mice given a copper injection. The expression of the Slc31a1 gene in 45-day-old mice is even reduced compared with intact wild-type animals. In suckling and young copper-injected mutants, the CTR1 protein is relocalized from the apical membrane to the cytoplasm of epithelial cells of proximal tubules, the process which prevents copper transport from the primary urine and, thus, protects cells against copper toxicity.
Collapse
|
2
|
Maung MT, Carlson A, Olea-Flores M, Elkhadragy L, Schachtschneider KM, Navarro-Tito N, Padilla-Benavides T. The molecular and cellular basis of copper dysregulation and its relationship with human pathologies. FASEB J 2021; 35:e21810. [PMID: 34390520 DOI: 10.1096/fj.202100273rr] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 06/23/2021] [Accepted: 07/07/2021] [Indexed: 12/16/2022]
Abstract
Copper (Cu) is an essential micronutrient required for the activity of redox-active enzymes involved in critical metabolic reactions, signaling pathways, and biological functions. Transporters and chaperones control Cu ion levels and bioavailability to ensure proper subcellular and systemic Cu distribution. Intensive research has focused on understanding how mammalian cells maintain Cu homeostasis, and how molecular signals coordinate Cu acquisition and storage within organs. In humans, mutations of genes that regulate Cu homeostasis or facilitate interactions with Cu ions lead to numerous pathologic conditions. Malfunctions of the Cu+ -transporting ATPases ATP7A and ATP7B cause Menkes disease and Wilson disease, respectively. Additionally, defects in the mitochondrial and cellular distributions and homeostasis of Cu lead to severe neurodegenerative conditions, mitochondrial myopathies, and metabolic diseases. Cu has a dual nature in carcinogenesis as a promotor of tumor growth and an inducer of redox stress in cancer cells. Cu also plays role in cancer treatment as a component of drugs and a regulator of drug sensitivity and uptake. In this review, we provide an overview of the current knowledge of Cu metabolism and transport and its relation to various human pathologies.
Collapse
Affiliation(s)
- May T Maung
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT, USA
| | - Alyssa Carlson
- Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, CT, USA
| | - Monserrat Olea-Flores
- Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
| | - Lobna Elkhadragy
- Department of Radiology, University of Illinois at Chicago, Chicago, IL, USA
| | - Kyle M Schachtschneider
- Department of Radiology, University of Illinois at Chicago, Chicago, IL, USA.,Department of Biochemistry & Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA.,National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Napoleon Navarro-Tito
- Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Guerrero, Mexico
| | | |
Collapse
|
3
|
Herman S, Lipiński P, Ogórek M, Starzyński R, Grzmil P, Bednarz A, Lenartowicz M. Molecular Regulation of Copper Homeostasis in the Male Gonad during the Process of Spermatogenesis. Int J Mol Sci 2020; 21:ijms21239053. [PMID: 33260507 PMCID: PMC7730223 DOI: 10.3390/ijms21239053] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 12/21/2022] Open
Abstract
Owing to its redox properties, copper is a cofactor of enzymes that catalyze reactions in fundamental metabolic processes. However, copper-oxygen interaction, which is a source of toxic oxygen radicals generated by the Fenton reaction, makes copper a doubled-edged-sword in an oxygen environment. Among the microelements influencing male fertility, copper plays a special role because both copper deficiency and overload in the gonads worsen spermatozoa quality and disturb reproductive function in mammals. Male gametes are produced during spermatogenesis, a multi-step process that consumes large amounts of oxygen. Germ cells containing a high amount of unsaturated fatty acids in their membranes are particularly vulnerable to excess copper-mediated oxidative stress. In addition, an appropriate copper level is necessary to initiate meiosis in premeiotic germ cells. The balance between essential and toxic copper concentrations in germ cells at different stages of spermatogenesis and in Sertoli cells that support their development is handled by a network of copper importers, chaperones, recipient proteins, and exporters. Here, we describe coordinated regulation/functioning of copper-binding proteins expressed in germ and Sertoli cells with special emphasis on copper transporters, copper transporting ATPases, and SOD1, a copper-dependent antioxidant enzyme. These and other proteins assure copper bioavailability in germ cells and protection against copper toxicity.
Collapse
Affiliation(s)
- Sylwia Herman
- Department of Genetics and Evolution, Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland; (S.H.); (M.O.); (P.G.); (A.B.)
| | - Paweł Lipiński
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology, Polish Academy of Sciences, 05-552 Magdalenka, Jastrzębiec, Poland; (P.L.); (R.S.)
| | - Mateusz Ogórek
- Department of Genetics and Evolution, Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland; (S.H.); (M.O.); (P.G.); (A.B.)
| | - Rafał Starzyński
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology, Polish Academy of Sciences, 05-552 Magdalenka, Jastrzębiec, Poland; (P.L.); (R.S.)
| | - Paweł Grzmil
- Department of Genetics and Evolution, Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland; (S.H.); (M.O.); (P.G.); (A.B.)
| | - Aleksandra Bednarz
- Department of Genetics and Evolution, Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland; (S.H.); (M.O.); (P.G.); (A.B.)
| | - Małgorzata Lenartowicz
- Department of Genetics and Evolution, Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland; (S.H.); (M.O.); (P.G.); (A.B.)
- Correspondence:
| |
Collapse
|
4
|
Cichon I, Ortmann W, Bednarz A, Lenartowicz M, Kolaczkowska E. Reduced Neutrophil Extracellular Trap (NET) Formation During Systemic Inflammation in Mice With Menkes Disease and Wilson Disease: Copper Requirement for NET Release. Front Immunol 2020; 10:3021. [PMID: 32010131 PMCID: PMC6974625 DOI: 10.3389/fimmu.2019.03021] [Citation(s) in RCA: 9] [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: 08/01/2019] [Accepted: 12/10/2019] [Indexed: 12/13/2022] Open
Abstract
Neutrophil extracellular traps (NETs) contribute to pathological disorders, and their release was directly linked to numerous diseases. With intravital microscopy (IVM), we showed previously that NETs also contribute to the pathology of systemic inflammation and are strongly deposited in liver sinusoids. Over a decade since NET discovery, still not much is known about the metabolic or microenvironmental aspects of their formation. Copper is a vital trace element essential for many biological processes, albeit its excess is potentially cytotoxic; thus, copper levels are tightly controlled by factors such as copper transporting ATPases, ATP7A, and ATP7B. By employing IVM, we studied the impact of copper on NET formation during endotoxemia in liver vasculature on two mice models of copper excess or deficiency, Wilson (ATP7B mutants) and Menkes (ATP7A mutants) diseases, respectively. Here, we show that respective ATP7 mutations lead to diminished NET release during systemic inflammation despite unaltered intrinsic capacity of neutrophils to cast NETs as tested ex vivo. In Menkes disease mice, the in vivo effect is mostly due to diminished neutrophil infiltration of the liver as unmutated mice with a subchronic copper deficiency release even more NETs than their controls during endotoxemia, whereas in Wilson disease mice, excess copper directly diminishes the capacity to release NETs, and this was further confirmed by ex vivo studies on isolated neutrophils co-cultured with exogenous copper and a copper-chelating agent. Taken together, the study extends our understanding on how microenvironmental factors affect NET release by showing that copper is not a prerequisite for NET release but its excess affects the trap casting by neutrophils.
Collapse
Affiliation(s)
- Iwona Cichon
- Department of Experimental Hematology, Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków, Poland
| | - Weronika Ortmann
- Department of Experimental Hematology, Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków, Poland
| | - Aleksandra Bednarz
- Department of Genetics and Evolutionism, Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków, Poland
| | - Malgorzata Lenartowicz
- Department of Genetics and Evolutionism, Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków, Poland
| | - Elzbieta Kolaczkowska
- Department of Experimental Hematology, Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków, Poland
| |
Collapse
|
5
|
Sun G, Zhu P, Dai Y, Chen W. Bioinformatics Analysis of the Core Genes Related to Lupus Nephritis Through a Network and Pathway-Based Approach. DNA Cell Biol 2019; 38:639-650. [PMID: 31090450 DOI: 10.1089/dna.2019.4631] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
In this study, we explored the genes genetically associated with lupus nephritis (LN), and their function by bioinformatics analysis. We collected genes potentially associated with LN from National Center for Biotechnology Information Center (NCBI-Gene) and Online Mendelian Inheritance in Man (OMIM) databases. The major bioinformatics analysis linked with genes was then revealed by weighted gene co-expression network analysis (WGCNA), crosstalk analysis, functional analysis, and Pivot algorithm. Two hundred twenty-three LN-related genes were obtained by intersecting NCBI-Gene and OMIM databases. Two thousand five hundred sixty-eight LN-related proteins and 23 modules were excavated by String protein interaction network and WGCNA co-expression analysis, respectively. Pivot algorithm included no coding RNA, transcription factor and drug indicated the high-count correlation-associated modules related to cancer, kidney pathophysiological changes, and kidney injury, respectively. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis based on 23 modules revealed LN-related genes mainly involved in immune response. Moreover, 19 genes that came from intersection of LN, arthritis, pleurisy, and myocarditis have close relationship with immune diseases and immune processes. Our results from this research may have important implications for understanding the genes underlying LN. Also, the framework proposed in this work can be used to research pathological molecular network and genes related to LN.
Collapse
Affiliation(s)
- Guoping Sun
- 1 Central Lab of Shenzhen Pingshan People's Hospital, Shenzhen, China
| | - Peng Zhu
- 1 Central Lab of Shenzhen Pingshan People's Hospital, Shenzhen, China
| | - Yong Dai
- 2 Clinical Medical Research Center, Second Clinical Medical College, Jinan University, Shenzhen People's Hospital, Shenzhen, China
| | - Wenbiao Chen
- 3 State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| |
Collapse
|
6
|
Ogórek M, Lenartowicz M, Starzyński R, Jończy A, Staroń R, Doniec A, Krzeptowski W, Bednarz A, Pierzchała O, Lipiński P, Rajfur Z, Baster Z, Gibas-Tybur P, Grzmil P. Atp7a and Atp7b regulate copper homeostasis in developing male germ cells in mice. Metallomics 2018; 9:1288-1303. [PMID: 28820536 DOI: 10.1039/c7mt00134g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The maintenance of copper homeostasis is critical for all cells. As learned from mice with disturbed copper metabolism, this trace element is also important for spermatogenesis. The experiments conducted in yeasts have demonstrated that appropriate copper level must be preserved to enable meiosis progression; however, increased copper level is toxic for cells. This study aims to analyze the expression profile of Atp7a and Atp7b and other genes encoding copper-related proteins during spermatogenesis in mice. Using the transcripts and protein detection techniques, we demonstrate that within seminiferous tubuli, ATP7A is mainly present in early meiotic germ cells (leptotene to pachytene spermatocytes) and in Sertoli cells (SCs). During spermatogenesis, the progression Atp7a expression profile corresponds to Slc31a1 (encoding copper importer CTR1) and Atox1 (encoding chaperon protein, which delivers copper from CTR1 to ATP7A and ATP7B) expression, suggesting that male germ cells retrieve copper and ATP7A protects them from copper overdose. In contrast, ATP7B protein is observed in SCs and near elongated spermatids; thus, its function seems to be related to copper extraction during spermiogenesis. This is the first study to give a comprehensive view on the activity of copper-related genes during spermatogenesis in mice.
Collapse
Affiliation(s)
- Mateusz Ogórek
- Department of Genetics and Evolution, Institute of Zoology and Biomedical Research, Jagiellonian University Kraków, Gronostajowa 9, 30-387 Kraków, Poland.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Song L, Ye W, Cui Y, Lu J, Zhang Y, Ding N, Hu W, Pei H, Yue Z, Zhou G. Ecto-5'-nucleotidase (CD73) is a biomarker for clear cell renal carcinoma stem-like cells. Oncotarget 2018; 8:31977-31992. [PMID: 28404888 PMCID: PMC5458263 DOI: 10.18632/oncotarget.16667] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 03/17/2017] [Indexed: 12/16/2022] Open
Abstract
Identification of a specific biomarker for cancer stem cells (CSCs) is of potential applications in the development of effective therapeutic strategies for renal cell carcinoma (RCC). In this study, both the RCC cell line 786-O and surgically removed clear cell RCC (ccRCC) tissues were implemented to grew as spheroids in serum-free medium supplemented with mitogens. This subpopulation possessed key characteristics defining CSCs. We also identified that surgically removed ccRCC tissues were heterogenic and there was a subpopulation of cells that was highly stained with rhodamine-123. Based on membrane-proteomic analyses, CD73 was identified as a candidate biomarker. We further found that CD73high cells were highly tumorigenic. As few as 100 CD73high cells were capable of forming xenograft tumors in non obese diabetic/severe combined immunodeficiency disease mice, whereas 1 × 105 CD73low cells did not initiate tumor formation. During successive culture, the CD73high population regenerated both CD73high and CD73low cells, whereas the CD73low population remained low expression level of CD73. Furthermore, the CD73high cells were more resistant to radiation and DNA-damaging agents than the CD73low cells, and expressed a panel of 'stemness' genes at a higher level than the CD73low cells. These findings suggest that a high level of CD73 expression is a bona fide biomarker of ccRCC stem-like cells. Future research will aim at the elucidation of the underlying mechanisms of CD73 in RCC development and the distinct aspects of ccRCC stem-like cells from other tumor types.
Collapse
Affiliation(s)
- Lei Song
- Medical College, Northwest Minzu University, Lanzhou 730030, China.,Department of Space Radiobiology, Key Laboratory of Heavy Ion Radiation Biology and Medicine, Institute of Modem Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Wenling Ye
- Medical College, Henan University, Kaifeng 475001, China.,Department of Space Radiobiology, Key Laboratory of Heavy Ion Radiation Biology and Medicine, Institute of Modem Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Yong Cui
- Department of Urology Surgery, Shuyang Hospital of Traditional Chinese Medicine, Suqian 223600, China.,Department of Space Radiobiology, Key Laboratory of Heavy Ion Radiation Biology and Medicine, Institute of Modem Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Jianzhong Lu
- Institute of Urology, Department of Urology, Gansu Nephro-Urological Clinical Center, Key Laboratory of Urological Diseases in Gansu Province, Lanzhou University Second Hospital, Lanzhou 730030, China
| | - Yanan Zhang
- Department of Space Radiobiology, Key Laboratory of Heavy Ion Radiation Biology and Medicine, Institute of Modem Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Nan Ding
- Department of Space Radiobiology, Key Laboratory of Heavy Ion Radiation Biology and Medicine, Institute of Modem Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Wentao Hu
- School of Radiation Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China
| | - Hailong Pei
- School of Radiation Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China
| | - Zhongjin Yue
- Institute of Urology, Department of Urology, Gansu Nephro-Urological Clinical Center, Key Laboratory of Urological Diseases in Gansu Province, Lanzhou University Second Hospital, Lanzhou 730030, China
| | - Guangming Zhou
- School of Radiation Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou 215123, China
| |
Collapse
|
8
|
Copper therapy reduces intravascular hemolysis and derepresses ferroportin in mice with mosaic mutation (Atp7a mo-ms): An implication for copper-mediated regulation of the Slc40a1 gene expression. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1410-1421. [PMID: 28219768 DOI: 10.1016/j.bbadis.2017.02.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 02/09/2017] [Accepted: 02/15/2017] [Indexed: 02/06/2023]
Abstract
Mosaic mutant mice displaying functional dysfunction of Atp7a copper transporter (the Menkes ATPase) are an established animal model of Menkes disease and constitute a convenient tool for investigating connections between copper and iron metabolisms. This model allows to explore changes in iron metabolism in suckling mutant mice suffering from systemic copper deficiency as well as in young and adult ones undergone copper therapy, which reduces lethal effect of the Atp7a gene mutation. Our recent study demonstrated that 14-day-old mosaic mutant males display blood cell abnormalities associated with intravascular hemolysis, and show disturbances in the functioning of the hepcidin-ferroportin regulatory axis, which controls systemic iron homeostasis. We thus aimed to check whether copper supplementation recovers mutants from hemolytic insult and rebalance systemic iron regulation. Copper supplementation of 14-day-old mosaic mutants resulted in the reestablishment of hematological status, attenuation of hepicidin and concomitant induction of the iron exporter ferroportin/Slc40a1 expression in the liver, down-regulated in untreated mutants. Interestingly, treatment of wild-type males with copper, induced hepcidin-independent up-regulation of ferroportin protein level in hepatic macrophages in both young and adult (6-month-old) animals. Stimulatory effect of copper on ferroportin mRNA and protein levels was confirmed in bone marrow-derived macrophages isolated from both wild-type and mosaic mutant males. Our study indicates that copper is an important player in the regulation of the Slc40a1 gene expression.
Collapse
|
9
|
Bhattacharjee A, Yang H, Duffy M, Robinson E, Conrad-Antoville A, Lu YW, Capps T, Braiterman L, Wolfgang M, Murphy MP, Yi L, Kaler SG, Lutsenko S, Ralle M. The Activity of Menkes Disease Protein ATP7A Is Essential for Redox Balance in Mitochondria. J Biol Chem 2016; 291:16644-58. [PMID: 27226607 PMCID: PMC4974379 DOI: 10.1074/jbc.m116.727248] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Indexed: 11/13/2022] Open
Abstract
Copper-transporting ATPase ATP7A is essential for mammalian copper homeostasis. Loss of ATP7A activity is associated with fatal Menkes disease and various other pathologies. In cells, ATP7A inactivation disrupts copper transport from the cytosol into the secretory pathway. Using fibroblasts from Menkes disease patients and mouse 3T3-L1 cells with a CRISPR/Cas9-inactivated ATP7A, we demonstrate that ATP7A dysfunction is also damaging to mitochondrial redox balance. In these cells, copper accumulates in nuclei, cytosol, and mitochondria, causing distinct changes in their redox environment. Quantitative imaging of live cells using GRX1-roGFP2 and HyPer sensors reveals highest glutathione oxidation and elevation of H2O2 in mitochondria, whereas the redox environment of nuclei and the cytosol is much less affected. Decreasing the H2O2 levels in mitochondria with MitoQ does not prevent glutathione oxidation; i.e. elevated copper and not H2O2 is a primary cause of glutathione oxidation. Redox misbalance does not significantly affect mitochondrion morphology or the activity of respiratory complex IV but markedly increases cell sensitivity to even mild glutathione depletion, resulting in loss of cell viability. Thus, ATP7A activity protects mitochondria from excessive copper entry, which is deleterious to redox buffers. Mitochondrial redox misbalance could significantly contribute to pathologies associated with ATP7A inactivation in tissues with paradoxical accumulation of copper (i.e. renal epithelia).
Collapse
Affiliation(s)
| | | | - Megan Duffy
- the Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239
| | - Emily Robinson
- the Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239
| | - Arianrhod Conrad-Antoville
- the Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239
| | | | - Tony Capps
- the Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239
| | | | - Michael Wolfgang
- Cell Biology Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Michael P Murphy
- the Medical Research Council Mitochondrial Biology Unit, Cambridge CB2 0XY, United Kingdom, and
| | - Ling Yi
- the Section on Translational Neuroscience, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Stephen G Kaler
- the Section on Translational Neuroscience, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | | | - Martina Ralle
- the Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239,
| |
Collapse
|
10
|
Lenartowicz M, Krzeptowski W, Lipiński P, Grzmil P, Starzyński R, Pierzchała O, Møller LB. Mottled Mice and Non-Mammalian Models of Menkes Disease. Front Mol Neurosci 2015; 8:72. [PMID: 26732058 PMCID: PMC4684000 DOI: 10.3389/fnmol.2015.00072] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 11/06/2015] [Indexed: 12/27/2022] Open
Abstract
Menkes disease is a multi-systemic copper metabolism disorder caused by mutations in the X-linked ATP7A gene and characterized by progressive neurodegeneration and severe connective tissue defects. The ATP7A protein is a copper (Cu)-transporting ATPase expressed in all tissues and plays a critical role in the maintenance of copper homeostasis in cells of the whole body. ATP7A participates in copper absorption in the small intestine and in copper transport to the central nervous system (CNS) across the blood-brain-barrier (BBB) and blood–cerebrospinal fluid barrier (BCSFB). Cu is essential for synaptogenesis and axonal development. In cells, ATP7A participates in the incorporation of copper into Cu-dependent enzymes during the course of its maturation in the secretory pathway. There is a high degree of homology (>80%) between the human ATP7A and murine Atp7a genes. Mice with mutations in the Atp7a gene, called mottled mutants, are well-established and excellent models of Menkes disease. Mottled mutants closely recapitulate the Menkes phenotype and are invaluable for studying Cu-metabolism. They provide useful models for exploring and testing new forms of therapy in Menkes disease. Recently, non-mammalian models of Menkes disease, Drosophila melanogaster and Danio rerio mutants were used in experiments which would be technically difficult to carry out in mammals.
Collapse
Affiliation(s)
- Małgorzata Lenartowicz
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University Kraków, Poland
| | - Wojciech Krzeptowski
- Department of Cell Biology and Imaging, Institute of Zoology, Jagiellonian University Kraków, Poland
| | - Paweł Lipiński
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences Wólka Kosowska, Poland
| | - Paweł Grzmil
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University Kraków, Poland
| | - Rafał Starzyński
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences Wólka Kosowska, Poland
| | - Olga Pierzchała
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University Kraków, Poland
| | - Lisbeth Birk Møller
- Applied Human Molecular Genetics, Kennedy Center, Rigshospitalet, Copenhagen University Hospital Glostrup, Denmark
| |
Collapse
|
11
|
Møller LB. Small amounts of functional ATP7A protein permit mild phenotype. J Trace Elem Med Biol 2015; 31:173-7. [PMID: 25172213 DOI: 10.1016/j.jtemb.2014.07.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 06/11/2014] [Accepted: 07/03/2014] [Indexed: 11/15/2022]
Abstract
Mutations in ATP7A lead to at least three allelic disorders: Menkes disease (MD), Occipital horn syndrome and X-linked distal motor neuropathy. These disorders are mainly seen in male individuals, but a few affected females have been described. More than 400 different mutations have been identified in the ATP7A gene. We have conducted several studies in the hope of uncovering the relationship between genotype and phenotype. We have examined the X-inactivation pattern in affected females, the effect of exon-deletions and--duplications, and splice-site mutations on the composition and amount of ATP7A transcript, and we have examined the structural location of missense mutations. The X-inactivation pattern did not fully explain the manifestation of MD in a small fraction of carriers. Most of the affected females had preferential inactivation of the X-chromosome with the normal ATP7A gene, but a few individuals exhibited preferential inactivation of the X-chromosome with the mutated ATP7A gene. The observed mild phenotype in some patients with mutations that effect the composition of the ATP7A transcript, seems to be explained by the presence of a small amount of normal ATP7A transcript. The location of missense mutations on structural models of the ATP7A protein suggests that affected conserved residues generally lead to a severe phenotype. The ATP7A protein traffics within the cells. At low copper levels, ATP7A locates to the Trans-Golgi Network (TGN) to load cuproenzymes with copper, whereas at higher concentrations, ATP7A shifts to the post-Golgi compartments or to the plasma membrane to export copper out of the cell. Impaired copper-regulation trafficking has been observed for ATP7A mutants, but its impact on the clinical outcome is not clear. The major problem in patients with MD seems to be insufficient amounts of copper in the brain. In fact, prenatal treatment of mottled mice as a model for human MD with a combination of chelator and copper, produces a slight increase in copper levels in the brain which perhaps leads to longer survival and more active behavior. In conclusion, small amounts of copper at the right location seem to relieve the symptoms.
Collapse
Affiliation(s)
- Lisbeth Birk Møller
- Center for Applied Human Genetics, Kennedy Center, Rigshospitalet, Gl. Landevej 7, 2600 Glostrup, Denmark.
| |
Collapse
|
12
|
Lenartowicz M, Starzyński RR, Krzeptowski W, Grzmil P, Bednarz A, Ogórek M, Pierzchała O, Staroń R, Gajowiak A, Lipiński P. Haemolysis and perturbations in the systemic iron metabolism of suckling, copper-deficient mosaic mutant mice - an animal model of Menkes disease. PLoS One 2014; 9:e107641. [PMID: 25247420 PMCID: PMC4172471 DOI: 10.1371/journal.pone.0107641] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/13/2014] [Indexed: 01/25/2023] Open
Abstract
The biological interaction between copper and iron is best exemplified by the decreased activity of multicopper ferroxidases under conditions of copper deficiency that limits the availability of iron for erythropoiesis. However, little is known about how copper deficiency affects iron homeostasis through alteration of the activity of other copper-containing proteins, not directly connected with iron metabolism, such as superoxide dismutase 1 (SOD1). This antioxidant enzyme scavenges the superoxide anion, a reactive oxygen species contributing to the toxicity of iron via the Fenton reaction. Here, we analyzed changes in the systemic iron metabolism using an animal model of Menkes disease: copper-deficient mosaic mutant mice with dysfunction of the ATP7A copper transporter. We found that the erythrocytes of these mutants are copper-deficient, display decreased SOD1 activity/expression and have cell membrane abnormalities. In consequence, the mosaic mice show evidence of haemolysis accompanied by haptoglobin-dependent elimination of haemoglobin (Hb) from the circulation, as well as the induction of haem oxygenase 1 (HO1) in the liver and kidney. Moreover, the hepcidin-ferroportin regulatory axis is strongly affected in mosaic mice. These findings indicate that haemolysis is an additional pathogenic factor in a mouse model of Menkes diseases and provides evidence of a new indirect connection between copper deficiency and iron metabolism.
Collapse
Affiliation(s)
- Małgorzata Lenartowicz
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Kraków, Poland
| | - Rafał R. Starzyński
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Magdalenka, Poland
| | - Wojciech Krzeptowski
- Department of Cell Biology and Imaging, Institute of Zoology, Jagiellonian University, Kraków, Poland
| | - Paweł Grzmil
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Kraków, Poland
| | - Aleksandra Bednarz
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Kraków, Poland
| | - Mateusz Ogórek
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Kraków, Poland
| | - Olga Pierzchała
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Kraków, Poland
| | - Robert Staroń
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Magdalenka, Poland
| | - Anna Gajowiak
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Magdalenka, Poland
| | - Paweł Lipiński
- Department of Molecular Biology, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Magdalenka, Poland
| |
Collapse
|
13
|
Nomura S, Nozaki S, Hamazaki T, Takeda T, Ninomiya E, Kudo S, Hayashinaka E, Wada Y, Hiroki T, Fujisawa C, Kodama H, Shintaku H, Watanabe Y. PET imaging analysis with 64Cu in disulfiram treatment for aberrant copper biodistribution in Menkes disease mouse model. J Nucl Med 2014; 55:845-51. [PMID: 24627433 DOI: 10.2967/jnumed.113.131797] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
UNLABELLED Menkes disease (MD), an X-linked recessive disorder of copper metabolism caused by mutations in the copper-transporting ATP7A gene, results in growth failure and severe neurodegeneration in early childhood. Subcutaneous copper-histidine injection is the standard treatment for MD, but it has limited clinical efficacy. Furthermore, long-term copper injection causes excess copper accumulation in the kidneys, resulting in renal dysfunction. To attempt to resolve this issue, we used PET imaging with (64)Cu to investigate the effects of disulfiram on copper biodistribution in living mice serving as an animal model for MD (MD model mice). METHODS Macular mice were used as MD model mice, and C3H/He mice were used as wild-type mice. Mice were pretreated with 2 types of chelators (disulfiram, a lipophilic chelator, and d-penicillamine, a hydrophilic chelator) 30 min before (64)CuCl2 injection. After (64)CuCl2 injection, emission scans covering the whole body were performed for 4 h. After the PET scans, the brain and kidneys were analyzed for radioactivity with γ counting and autoradiography. RESULTS After copper injection alone, marked accumulation of radioactivity ((64)Cu) in the liver was demonstrated in wild-type mice, whereas in MD model mice, copper was preferentially accumulated in the kidneys (25.56 ± 3.01 percentage injected dose per gram [%ID/g]) and was detected to a lesser extent in the liver (13.83 ± 0.26 %ID/g) and brain (0.96 ± 0.08 %ID/g). Copper injection with disulfiram reduced excess copper accumulation in the kidneys (14.54 ± 2.68 %ID/g) and increased copper transport into the liver (29.42 ± 0.98 %ID/g) and brain (5.12 ± 0.95 %ID/g) of MD model mice. Copper injection with d-penicillamine enhanced urinary copper excretion and reduced copper accumulation in most organs in both mouse groups. Autoradiography demonstrated that disulfiram pretreatment induced copper transport into the brain parenchyma and reduced copper accumulation in the renal medulla. CONCLUSION PET studies with (64)Cu revealed that disulfiram had significant effects on the copper biodistribution of MD. Disulfiram increased copper transport into the brain and reduced copper uptake in the kidneys of MD model mice. The application of (64)Cu PET for the treatment of MD and other copper-related disorders may be useful in clinical settings.
Collapse
Affiliation(s)
- Shiho Nomura
- Department of Pediatrics, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
The mild form of menkes disease: a 34 year progress report on the original case. JIMD Rep 2012; 9:81-84. [PMID: 23430551 PMCID: PMC3565640 DOI: 10.1007/8904_2012_183] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 09/17/2012] [Accepted: 09/18/2012] [Indexed: 01/22/2023] Open
Abstract
Classical Menkes disease is a neurodegenerative disorder caused by mutations in the copper-transporting ATPase ATP7A gene which, when untreated, is usually fatal in early childhood. A mild form of Menkes disease was originally reported in 1981 and clinical progress of the patient at 10 years described subsequently. The causative mutation is c.4085C>T in exon 21, causing an alanine to valine substitution in the highly conserved TM7 domain at the C-terminal end of the Menkes protein. Here we report his status at 34 years of age. Intellectual impairment is mild. Ataxia has nearly resolved but motor retardation, dysarthria and an extreme slow speech rate remain. In contrast to patients with the occipital horn syndrome, there have been no connective tissue complications of his mild Menkes disease. He has been under long-term copper therapy for more than 30 years and he continues to enjoy a good quality of life.
Collapse
|
15
|
Haddad MR, Macri CJ, Holmes CS, Goldstein DS, Jacobson BE, Centeno JA, Popek EJ, Gahl WA, Kaler SG. In utero copper treatment for Menkes disease associated with a severe ATP7A mutation. Mol Genet Metab 2012; 107:222-8. [PMID: 22695177 PMCID: PMC3444639 DOI: 10.1016/j.ymgme.2012.05.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 05/11/2012] [Accepted: 05/11/2012] [Indexed: 10/28/2022]
Abstract
Menkes disease is a lethal X-linked recessive neurodegenerative disorder of copper transport caused by mutations in ATP7A, which encodes a copper-transporting ATPase. Early postnatal treatment with copper injections often improves clinical outcomes in affected infants. While Menkes disease newborns appear normal neurologically, analyses of fetal tissues including placenta indicate abnormal copper distribution and suggest a prenatal onset of the metal transport defect. In an affected fetus whose parents found termination unacceptable and who understood the associated risks, we began in utero copper histidine treatment at 31.5 weeks gestational age. Copper histidine (900 μg per dose) was administered directly to the fetus by intramuscular injection (fetal quadriceps or gluteus) under ultrasound guidance. Percutaneous umbilical blood sampling enabled serial measurement of fetal copper and ceruloplasmin levels that were used to guide therapy over a four-week period. Fetal copper levels rose from 17 μg/dL prior to treatment to 45 μg/dL, and ceruloplasmin levels from 39 mg/L to 122 mg/L. After pulmonary maturity was confirmed biochemically, the baby was delivered at 35.5 weeks and daily copper histidine therapy (250 μg sc b.i.d.) was begun. Despite this very early intervention with copper, the infant showed hypotonia, developmental delay, and electroencephalographic abnormalities and died of respiratory failure at 5.5 months of age. The patient's ATP7A mutation (Q724H), which severely disrupted mRNA splicing, resulted in complete absence of ATP7A protein on Western blots. These investigations suggest that prenatally initiated copper replacement is inadequate to correct Menkes disease caused by severe loss-of-function mutations, and that postnatal ATP7A gene addition represents a rational approach in such circumstances.
Collapse
Affiliation(s)
- Marie Reine Haddad
- Unit on Human Copper Metabolism, Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| | - Charles J. Macri
- Division of Maternal Fetal Medicine in the Department of Obstetrics and Gynecology, George Washington University School of Medicine, Washington, DC
| | - Courtney S. Holmes
- Section of Neurocardiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - David S. Goldstein
- Section of Neurocardiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Beryl E. Jacobson
- Department of Clinical Biochemistry, BC Children’s Hospital, Vancouver, British Columbia
| | - Jose A. Centeno
- Biophysical Toxicology, The Joint Pathology Center, Silver Spring, MD
| | - Edwina J. Popek
- Department of Pediatric Pathology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX
| | - Willam A. Gahl
- Section on Human Biochemical Genetics, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD
| | - Stephen G. Kaler
- Unit on Human Copper Metabolism, Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
| |
Collapse
|
16
|
Lenartowicz M, Krzeptowski W, Koteja P, Chrząścik K, Møller LB. Prenatal treatment of mosaic mice (Atp7a mo-ms) mouse model for Menkes disease, with copper combined by dimethyldithiocarbamate (DMDTC). PLoS One 2012; 7:e40400. [PMID: 22815746 PMCID: PMC3399861 DOI: 10.1371/journal.pone.0040400] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 06/09/2012] [Indexed: 02/07/2023] Open
Abstract
Menkes disease is a fatal neurodegenerative disorder in infants caused by mutations in the gene ATP7A which encodes a copper (Cu) transporter. Defects in ATP7A lead to accumulated copper in the small intestine and kidneys and to copper deficiencies in the brain and the liver. The copper level in the kidney in postnatal copper-treated Menkes patients may reach toxic levels. The mouse model, mosaic Atp7a mo-ms recapitulates the Menkes phenotype and die about 15.75±1.5 days of age. In the present study we found that prenatal treatment of mosaic murine fetuses throughout gestation days 7, 11, 15 and 18 with a combination of CuCl2 (50 mg/kg) and dimethyldithiocarbamate (DMDTC) (280 mg/kg) leads to an increase in survival to about 76±25.3 days, whereas treatment with CuCl2 alone (50 mg/kg) only leads to survival for about 21 days ±5 days. These copper-DMDTC treated mutants showed an improved locomotor activity performance and a gain in body mass. In contrast to treatment with CuCl2 alone, a significant increase in the amount of copper was observed in the brain after prenatal copper-DMDTC treatment as well as a decrease in the amount of accumulated copper in the kidney, both leading towards a normalization of the copper level. Although copper-DMDTC prenatal treatment only leads to a small increase in the sub-normal copper concentration in the liver and to an increase of copper in the already overloaded small intestine, the combined results suggest that prenatal copper-DMDTC treatment also should be considered for humans.
Collapse
Affiliation(s)
- Małgorzata Lenartowicz
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Krakow, Poland.
| | | | | | | | | |
Collapse
|
17
|
Lenartowicz M, Grzmil P, Shoukier M, Starzyński R, Marciniak M, Lipiński P. Mutation in the CPC motif-containing 6th transmembrane domain affects intracellular localization, trafficking and copper transport efficiency of ATP7A protein in mosaic mutant mice--an animal model of Menkes disease. Metallomics 2011; 4:197-204. [PMID: 22089129 DOI: 10.1039/c1mt00134e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Copper is an essential micronutrient for all living organisms. ATP7A protein is a copper-transporting ATPase which plays a vital role in the maintenance of cellular copper homeostasis in mammals. This protein is retained within the trans-Golgi network, but after binding copper it can be translocated to the cell membrane to participate in the efflux of excess Cu. Mutation of the ATP7A gene in humans results in the severe neurodegenerative disorder, Menkes disease. The mouse ATP7A homolog encodes a protein that plays the same role in copper transport. Mosaic mutant mice display a lethal phenotype which resembles Menkes disease, although the underlying molecular defect has not been characterized until now. In the present study we identified a G to C nucleotide exchange in exon 15 of the Atp7a gene in mosaic mutants, which resulted in an arginine to proline substitution in the highly conserved 6th transmembrane domain of the ATP7A protein. This mutated protein was mislocalized in kidney cells isolated from mosaic mutant mice, and following exposure of these cells to increased copper concentrations it was not translocated to the plasma membrane. Disturbance of ATP7A function in mosaic mice results in increased copper accumulation in the small intestine and kidneys, and in Cu deficiency in the brain, liver and heart. Mouse models of Menkes disease belong to the mottled mutant group. The mosaic mutant represents another interesting animal model for Menkes disease that will be of value in research on copper metabolism and transport in mammals.
Collapse
Affiliation(s)
- Małgorzata Lenartowicz
- Department of Genetics and Evolution, Institute of Zoology, Jagiellonian University, Ingardena 6, Gronostajowa 9, 30-387 Kraków, Poland.
| | | | | | | | | | | |
Collapse
|
18
|
Alterations in the expression of the Atp7a gene in the early postnatal development of the mosaic mutant mice (Atp7a mo-ms) - An animal model for Menkes disease. Gene Expr Patterns 2010; 11:41-7. [PMID: 20831904 DOI: 10.1016/j.gep.2010.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 08/30/2010] [Accepted: 09/02/2010] [Indexed: 01/16/2023]
Abstract
Copper is a trace element that is essential for the normal growth and development of all living organisms. In mammals, the ATP7A Cu-transporting ATPase is a key protein that is required for the maintenance of copper homeostasis. In both humans and mice, the ATP7A protein is coded by the X-linked ATP7A/Atp7a gene. Disturbances in copper metabolism caused by mutations in the ATP7A/Atp7a gene lead to severe metabolic syndromes Menkes disease in humans and the lethal mottled phenotype in mice. Mosaic is one of numerous mottled mutations and may serve as a model for a severe Menkes disease variant. In Menkes patients, mutations in the ATP7A gene often result in a decreased level of the normal ATP7A protein. The aim of this study was to analyse the expression of the Atp7a gene in mosaic mutants in early postnatal development, a critical period for starting copper supplementation therapy in both Menkes patients and mutant mice. Using real-time quantitative RT-PCR, we analysed the expression of the Atp7a gene in the brain, kidney and liver of newborn (P0.5) and suckling (P14) mice. Our results indicate that in mosaic P0.5 mutants, the Atp7a mRNA level is decreased in all analysed organs in comparison with wild-type animals. In two week-old mutants, a significant decrease was observed only in the kidney. In contrast, their hepatic level of Atp7a tended to be higher than in wild-type mice. We speculate that disturbance in the expression of the Atp7a gene and, consequently, change in the copper concentration of the organs, may contribute to the early fatal outcome of mosaic males.
Collapse
|