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Manjunatha B, Park SH, Kim K, Kundapur RR, Lee SJ. Pristine graphene induces cardiovascular defects in zebrafish (Danio rerio) embryogenesis. Environ Pollut 2018; 243:246-254. [PMID: 30176498 DOI: 10.1016/j.envpol.2018.08.058] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 08/18/2018] [Accepted: 08/19/2018] [Indexed: 06/08/2023]
Abstract
The multiple effect of pristine graphene (pG) toxicity on cardiovascular developmental defects was assessed using zebrafish as a model. Recently, the nanotoxicity is emerging as a critical issue, and it is more significant in embryogenesis. Especially, graphene and its derivatives have attracted a lot of interest in biomedical applications. However, very little is known about the toxic effects of pG which has been widely used carbon nanomaterial according to concentration and its effects on biological and cardiovascular development. In the present study, we examined the development of zebrafish embryos by exposing to pG (5, 10, 15, 20 and 25 μg/L) under different developmental toxicity end-points such as cardiotoxicity, cardiovascular defect, retardation of cardiac looping, apoptosis and globin expression analysis. For this, the developmental cardiotoxicity of pG at different concentrations and the specific cardiovascular defects thereof were elucidated for the first time. As a result, the exposure to pG was found to be a potential risk factor to cardiovascular system of zebrafish embryos. However, a further study on the variations of physical, molecular properties and mechanisms of nanotoxicity which vary depending on production method and surface functionalization is required. In addition, the potential risks of pG flakes to aquatic organisms and human health should be considered or checked before releasing them to the environment.
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Affiliation(s)
- Bangeppagari Manjunatha
- Center for Biofluid and Biomimic Research, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea
| | - Sung Ho Park
- Center for Biofluid and Biomimic Research, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea; Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea
| | - Kiwoong Kim
- Center for Biofluid and Biomimic Research, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea; Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea
| | | | - Sang Joon Lee
- Center for Biofluid and Biomimic Research, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea; Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea.
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2
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Uchida N, Haro-Mora JJ, Demirci S, Fujita A, Raines L, Hsieh MM, Tisdale JF. High-level embryonic globin production with efficient erythroid differentiation from a K562 erythroleukemia cell line. Exp Hematol 2018; 62:7-16.e1. [PMID: 29524566 PMCID: PMC8541692 DOI: 10.1016/j.exphem.2018.02.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 02/16/2018] [Accepted: 02/20/2018] [Indexed: 12/21/2022]
Abstract
A reliable cell line capable of robust in vitro erythroid differentiation would be useful to investigate red blood cell (RBC) biology and genetic strategies for RBC diseases. K562 cells are widely utilized for erythroid differentiation; however, current differentiation methods are insufficient to analyze globin proteins. In this study, we sought to improve erythroid differentiation from K562 cells to enable protein-level globin analysis. K562 cells were exposed to a variety of reagents, including hemin, rapamycin, imatinib, and/or decitabine (known erythroid inducers), and cultured in a basic culture medium or erythropoietin-based differentiation medium. All single reagents induced observable erythroid differentiation with higher glycophorin A (GPA) expression but were insufficient to produce detectable globin proteins. We then evaluated various combinations of these reagents and developed a method incorporating imatinib preexposure and an erythropoietin-based differentiation culture containing both rapamycin and decitabine capable of efficient erythroid differentiation, high-level GPA expression (>90%), and high-level globin production at protein levels detectable by hemoglobin electrophoresis and high performance liquid chromatography. In addition, β-globin gene transfer resulted in detectable adult hemoglobin. In summary, we developed an in vitro K562 erythroid differentiation model with high-level globin production. This model provides a practical evaluation tool for hemoglobin production in human erythroid cells.
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Affiliation(s)
- Naoya Uchida
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
| | - Juan J Haro-Mora
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Selami Demirci
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Atsushi Fujita
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Lydia Raines
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Matthew M Hsieh
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - John F Tisdale
- Sickle Cell Branch, National Heart Lung and Blood Institute/National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
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Wang YJ, Peng QY, Deng SY, Chen CX, Wu L, Huang L, Zhang LN. Hemin protects against oxygen-glucose deprivation-induced apoptosis activation via neuroglobin in SH-SY5Y cells. Neurochem Res 2017; 42:2208-2217. [PMID: 28316021 DOI: 10.1007/s11064-017-2230-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/28/2017] [Accepted: 03/10/2017] [Indexed: 02/07/2023]
Abstract
This study aimed to investigate the mechanism underlying the neuroprotective effect of hemin in oxygen-glucose deprivation (OGD)-treated neurons. OGD-treated SH-SY5Y cells (human neuroblastoma cells) were used in the study. The cellular viability of SH-SY5Y cells was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the cell apoptosis rate was determined by flow cytometry analysis with Annexin V-fluorescein isothiocyanate and propidium iodide staining with or without hemin pretreatment. Cell viability and apoptotic activation were detected after hemin administration combined with neuroglobin (Nqb), thioredoxin-1, peroxiredoxin-2, or heme oxygenase-1 siRNA transient transfection. The release of cytochrome c from mitochondria and the interaction between Ngb and cytochrome c were examined with hemin pretreatment. Hemin had a neuroprotective effect in OGD-treated SH-SY5Y cells, which was mainly mediated by the upregulation of Ngb. Moreover, the release of cytochrome c from mitochondria was inhibited by hemin-induced Ngb expression through facilitating the interaction of Ngb with cytochrome c in mitochondria. The present findings provided new insights into the neuroprotective mechanisms of hemin. It was concluded that low-dose hemin pretreatment had a neuroprotective effect in OGD-treated SH-SY5Y cells, through inhibiting cell apoptosis. The neuroprotective effects of hemin following hypoxic-ischemic neuronal damage were mainly mediated by Ngb. One underlying mechanism was hemin-induced overexpression of mitochondrial Ngb, which inhibited endogenous apoptosis via the association with cytochrome c.
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Affiliation(s)
- Yun-Jia Wang
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China
| | - Qian-Yi Peng
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China
| | - Song-Yun Deng
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China
| | - Cai-Xia Chen
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China
| | - Long Wu
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China
| | - Li Huang
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China
| | - Li-Na Zhang
- Department of Intensive Care Unit, Xiangya Hospital, Central South University, No 87, Xiangya Road, Changsha, 410008, China.
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Martyn GE, Quinlan KGR, Crossley M. The regulation of human globin promoters by CCAAT box elements and the recruitment of NF-Y. Biochim Biophys Acta Gene Regul Mech 2016; 1860:525-536. [PMID: 27718361 DOI: 10.1016/j.bbagrm.2016.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 09/30/2016] [Accepted: 10/03/2016] [Indexed: 01/01/2023]
Abstract
CCAAT boxes are motifs found within the proximal promoter of many genes, including the human globin genes. The highly conserved nature of CCAAT box motifs within the promoter region of both α-like and β-like globin genes emphasises the functional importance of the CCAAT sequence in globin gene regulation. Mutations within the β-globin CCAAT box result in β-thalassaemia, while mutations within the distal γ-globin CCAAT box cause the Hereditary Persistence of Foetal Haemoglobin, a benign condition which results in continued γ-globin expression during adult life. Understanding the transcriptional regulation of the globin genes is of particular interest, as reactivating the foetal γ-globin gene alleviates the symptoms of β-thalassaemia and sickle cell anaemia. NF-Y is considered to be the primary activating transcription factor which binds to globin CCAAT box motifs. Here we review recruitment of NF-Y to globin CCAAT boxes and the role NF-Y plays in regulating globin gene expression. This article is part of a Special Issue entitled: Nuclear Factor Y in Development and Disease, edited by Prof. Roberto Mantovani.
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Affiliation(s)
- Gabriella E Martyn
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052, Australia
| | - Kate G R Quinlan
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052, Australia
| | - Merlin Crossley
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052, Australia.
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Gleixner E, Ripp F, Gorr TA, Schuh R, Wolf C, Burmester T, Hankeln T. Knockdown of Drosophila hemoglobin suggests a role in O2 homeostasis. Insect Biochem Mol Biol 2016; 72:20-30. [PMID: 27001071 DOI: 10.1016/j.ibmb.2016.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 03/11/2016] [Accepted: 03/16/2016] [Indexed: 06/05/2023]
Abstract
Almost all insects are equipped with a tracheal system, which appears to be sufficient for O2 supply even in phases of high metabolic activity. Therefore, with the exception of a few species dwelling in hypoxic habitats, specialized respiratory proteins had been considered unnecessary in insects. The recent discovery and apparently universal presence of intracellular hemoglobins in insects has remained functionally unexplained. The fruitfly Drosophila melanogaster harbors three different globin genes (referred to as glob1-3). Glob1 is the most highly expressed globin and essentially occurs in the tracheal system and the fat body. To better understand the functions of insect globins, the levels of glob1 were modulated in Drosophila larvae and adults by RNAi-mediated knockdown and transgenic over-expression. No effects on the development were observed in flies with manipulated glob1 levels. However, the knockdown of glob1 led to a significantly reduced survival rate of adult flies under hypoxia (5% and 1.5% O2). Surprisingly, the glob1 knockdown flies also displayed increased resistance towards the reactive oxygen species-forming agent paraquat, which may be explained by a restricted availability of O2 resulting in decreased formation of harmful O2(-). In summary, our results suggest an important functional role of glob1 in O2 homeostasis, possibly by enhancing O2 supply.
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Affiliation(s)
- Eva Gleixner
- Institute of Molecular Genetics, University of Mainz, D-55099 Mainz, Germany
| | - Fabian Ripp
- Institute of Molecular Genetics, University of Mainz, D-55099 Mainz, Germany
| | - Thomas A Gorr
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, CH-8057 Zurich, Switzerland; Regenerative Medicine Program, University and University Hospital Zurich, CH-8901 Zurich, Switzerland
| | - Reinhard Schuh
- Max Planck Institute for Biophysical Chemistry, D-37077 Göttingen, Germany
| | - Christian Wolf
- Institute of Molecular Genetics, University of Mainz, D-55099 Mainz, Germany
| | - Thorsten Burmester
- Institute of Zoology and Zoological Museum, Biocenter Grindel, University of Hamburg, D-20146 Hamburg, Germany.
| | - Thomas Hankeln
- Institute of Molecular Genetics, University of Mainz, D-55099 Mainz, Germany.
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Oliveira KC, da Conceição RR, Piedade GC, de Souza JS, Sato MA, de Barros Maciel RM, Giannocco G. Thyroid hormone modulates neuroglobin and cytoglobin in rat brain. Metab Brain Dis 2015; 30:1401-8. [PMID: 26334191 DOI: 10.1007/s11011-015-9718-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 08/17/2015] [Indexed: 10/23/2022]
Abstract
Thyroid hormones (THs) are essential and crucial for brain development, playing a role in growth and differentiation. Two globins named neuroglobin (Ngb) and cytoglobin (Cygb) are located in the brain, and each one has different distribution and function: They seem to have similar action by providing O(2) for respiratory chain, and detoxification of reactive oxygen species (ROS) and nitric oxide (NO) protecting tissues against irreversible lesions. We aimed to investigate the influence of thyroid state in Ngb and Cygb metabolism in different brain regions and evaluate their responses in cerebellum, hippocampus and cerebral cortex (hereafter called as cortex) after supraphysiological doses at different time points of TH administration. Experiments were carried out in rats, divided in eight experimental groups Control (C), thyroidectomy (Tx), and thyroidectomy treated with jugular intravenous injection (i.v). T3 (100 μl/100 g) injection and sacrificed after 30, 60, 120 min and 6, 12 and 24 h. In cortex, we found increase in Ngb gene and protein expression in different time points compared to C group, however Cygb gene and protein expression were decreased. In hippocampus, Ngb and Cygb protein expression increased 24 h after i.v. T3 injection in comparison to Tx. In cerebellum, we found increased Ngb gene expression after 120 min, 6, 12 and 24 h after T3 administration compared to Tx, and in contrast, protein expression was found to be significantly increased only 12 and 24 h compared to Tx. Ngb and Cygb expression in brain is influenced by thyroid hormone state both by its lack or excess.
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Affiliation(s)
- Kelen Carneiro Oliveira
- Department Morphology and Physiology, Faculdade de Medicina do ABC, Santo Andre, SP, Brazil
- Department Medicine, Universidade Federal de Sao Paulo (UNIFESP), Rua Pedro de Toledo, Vila Clementino, Sao Paulo, SP, 04039032, Brazil
| | - Rodrigo Rodrigues da Conceição
- Department Medicine, Universidade Federal de Sao Paulo (UNIFESP), Rua Pedro de Toledo, Vila Clementino, Sao Paulo, SP, 04039032, Brazil
| | - Gisele Constantinov Piedade
- Department Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
| | - Janaina Sena de Souza
- Department Medicine, Universidade Federal de Sao Paulo (UNIFESP), Rua Pedro de Toledo, Vila Clementino, Sao Paulo, SP, 04039032, Brazil
| | - Monica Akemi Sato
- Department Morphology and Physiology, Faculdade de Medicina do ABC, Santo Andre, SP, Brazil
| | - Rui Monteiro de Barros Maciel
- Department Medicine, Universidade Federal de Sao Paulo (UNIFESP), Rua Pedro de Toledo, Vila Clementino, Sao Paulo, SP, 04039032, Brazil
| | - Gisele Giannocco
- Department Morphology and Physiology, Faculdade de Medicina do ABC, Santo Andre, SP, Brazil.
- Department Medicine, Universidade Federal de Sao Paulo (UNIFESP), Rua Pedro de Toledo, Vila Clementino, Sao Paulo, SP, 04039032, Brazil.
- Department Biological Sciences, Universidade Federal de Sao Paulo, Diadema, SP, Brazil.
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Doty RT, Phelps SR, Shadle C, Sanchez-Bonilla M, Keel SB, Abkowitz JL. Coordinate expression of heme and globin is essential for effective erythropoiesis. J Clin Invest 2015; 125:4681-91. [PMID: 26551679 DOI: 10.1172/jci83054] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/08/2015] [Indexed: 01/27/2023] Open
Abstract
Erythropoiesis requires rapid and extensive hemoglobin production. Heme activates globin transcription and translation; therefore, heme synthesis must precede globin synthesis. As free heme is a potent inducer of oxidative damage, its levels within cellular compartments require stringent regulation. Mice lacking the heme exporter FLVCR1 have a severe macrocytic anemia; however, the mechanisms that underlie erythropoiesis dysfunction in these animals are unclear. Here, we determined that erythropoiesis failure occurs in these animals at the CFU-E/proerythroblast stage, a point at which the transferrin receptor (CD71) is upregulated, iron is imported, and heme is synthesized--before ample globin is produced. From the CFU-E/proerythroblast (CD71(+) Ter119(-) cells) stage onward, erythroid progenitors exhibited excess heme content, increased cytoplasmic ROS, and increased apoptosis. Reducing heme synthesis in FLVCR1-defient animals via genetic and biochemical approaches improved the anemia, implying that heme excess causes, and is not just associated with, the erythroid marrow failure. Expression of the cell surface FLVCR1 isoform, but not the mitochondrial FLVCR1 isoform, restored normal rbc production, demonstrating that cellular heme export is essential. Together, these studies provide insight into how heme is regulated to allow effective erythropoiesis, show that erythropoiesis fails when heme is excessive, and emphasize the importance of evaluating Ter119(-) erythroid cells when studying erythroid marrow failure in murine models.
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Ross J, Ikawa Y, Gielen J, Packman S, Leder P. Induction of globin mRNA in Friend leukemia virus-infected cells and its presence in viral 60S RNA. Bibl Haematol 2015:205-20. [PMID: 1172437 DOI: 10.1159/000397535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The Friend leukemia virus (FLV)-infected cell line, T-3-Cl-2, undergoes a form of erythroid differentiation in culture when treated with an appropriate inducer, such as dimethylsulfoxide ((CH3)2SO). Thus, whereas untreated cells contain no detectable hemoglobin, treated cells accumulate hemoglobin in quantities comparable to those in the mature mouse red blood cell. We have investigated the mechanism of hemoglobin induction by quantitating the number of globin genes and the amount of globin mRNA in cells before and during the period of hemoglobin accumulation. The results indicate the number of globin genes does not change as the cells accumulate hemogtobin: There are less than 5 globin genes per haploid genome. On the other hand, whereas cells lacking hemoglobin contain little, if any, globin mRNA, hemoglobin-containing cells accumulate, on the average, 8,000 molecules of globin mRNA per cell. The most direct, although, by no means, the only interpretation of these results is that the induction of hemoglobin synthesis involves transcriptional activation of the globin genes. Using this same cell line, we show that mouse globin mRNA sequences are also present in viral particles purified from the culture medium of globin-producing cells. These globin mRNA sequences are absent from viral particles derived from T-3-Cl-2 cells which are not producing globin mRNA. Virus-associated globin mRNA sequences sediment in association with 60S viral RNA complex as well as in free, 9S form. However, under mild denaturing conditions which result in the conversion of viral 60 S RNA to 30S and smaller forms, all the globin sequences sediment as 9S RNA. Appropriate control experiments indicate that the virus-associated globin mRNA is resistant to degradation by exogenous ribonuclease; that exogenously added globin mRNA does not become associated with the 60S viral RNA complex; and that globin mRNA can be detected in virions derived from cells both induced for and constitutively synthesizing globin mRNA. The presence of globin mRNA sequences in FLV particles has important implications in terms of our ability to distinguish between host and viral RNAs in viral particles and in terms of the possible role RNA tumor viruses might play in transduction of genetic information.
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Zhang R, Li Z, Shi W, Xu R. [Expression, purification, and characterization of fusion protein TAT-cytoglobin]. Sheng Wu Gong Cheng Xue Bao 2014; 30:1247-1255. [PMID: 25423754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
he aim of this study was to obtain a cell-penetrating cytoglobin (Cygb), which combines the transmembrane function of cell-penetrating peptides TAT with the anti-aging and anti-fibrotic role of cytoglobin. The Cygb gene was complexed with TAT gene by overlapping PCR, inserted into the vector pET22b to construct the recombinant expression plasmid (pET22b-TAT-Cygb) and then transformed into Escherichia coli BL21 (DE3). The fusion protein TAT-Cygb, whose expression was induced by lactose, was purified by CM Sepharose Fast Flow Protocol and verified by Western blotting. The final TAT-Cygb had a molecular weight of 23 kDa with 95% purity, as shown by SDS-PAGE. As demonstrated by bioactivity experiments, TAT-Cygb exhibited a high specific peroxidase activity up to (422.30 ± 0.36) U/mg. Both TAT-Cygb and Cygb pretreatment group could protect Hacat cells against oxidation of H2O2, but only TAT-Cygb treatment group could remedy cells injuried by H2O2 (RGR = 98%), which was significantly different from Cygb treatment group (RGR = 79%). We successfully obtained the bioactive and cell-penetrating fusion protein TAT-Cygb that has the potential application in anti-aging, anti-fibrotic and anti-cancer.
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Chakraborty S, John R, Nag A. Cytoglobin in tumor hypoxia: novel insights into cancer suppression. Tumour Biol 2014; 35:6207-19. [PMID: 24816917 DOI: 10.1007/s13277-014-1992-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 04/17/2014] [Indexed: 01/19/2023] Open
Abstract
Emerging new and intriguing roles of cytoglobin (Cygb) have attracted considerable attention of cancer researchers in recent years. Hypoxic upregulation of Cygb as well as its altered expression in various human cancers suggest another possible role of this newly discovered globin in tumor cell response under low oxygen tension. Since tumor hypoxia is strongly associated with malignant progression of disease and poor treatment response, it constitutes an area of paramount importance for rational design of cancer selective therapies. However, the mechanisms involved during this process are still elusive. This review outlines the current understanding of Cygb's involvement in tumor hypoxia and discusses its role in tumorigenesis. A better perception of Cygb in tumor hypoxia response is likely to open novel perspectives for future tumor therapy.
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Affiliation(s)
- Sankalpa Chakraborty
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Marg, New Delhi, 110021, India
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Song X, Xu R, Xie F, Zhu H, Zhu J, Wang X. Hemin offers neuroprotection through inducing exogenous neuroglobin in focal cerebral hypoxic-ischemia in rats. Int J Clin Exp Pathol 2014; 7:2163-2171. [PMID: 24966924 PMCID: PMC4069941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 04/10/2014] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To investigate the inducible effect of hemin on exogenous neuroglobin (Ngb) in focal cerebral hypoxic-ischemia in rats. METHODS 125 healthy SD rats were randomly divided into five groups: sham-operation control group, operation group, hemin treatment group, exogenous Ngb treatment group, and hemin and exogenous Ngb joint treatment group. Twenty-four hours after focal cerebral hypoxic-ischemia, Ngb expression was evaluated by immunocytochemistry, RT-PCR, and western blot analyses, while the brain water content and infarct volume were examined. RESULTS Immunocytochemistry, RT-PCR, and western blot analyses showed more pronounced Ngb expression in the hemin and exogenous Ngb joint operation group than in the hemin or exogenous Ngb individual treatment groups, thus producing significant differences in brain water content and infarct volume (p<0.05). CONCLUSIONS Hemin may be beneficial in protecting against focal cerebral hypoxic-ischemia through inducing the expression of exogenous Ngb.
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MESH Headings
- Animals
- Brain/drug effects
- Brain/metabolism
- Brain/pathology
- Brain Edema/metabolism
- Brain Edema/pathology
- Brain Edema/prevention & control
- Cytoprotection
- Disease Models, Animal
- Gene Expression Regulation
- Gene Transfer Techniques
- Genetic Therapy/methods
- Globins/biosynthesis
- Globins/genetics
- Hemin/pharmacology
- Hypoxia-Ischemia, Brain/genetics
- Hypoxia-Ischemia, Brain/metabolism
- Hypoxia-Ischemia, Brain/pathology
- Hypoxia-Ischemia, Brain/prevention & control
- Infarction, Middle Cerebral Artery/genetics
- Infarction, Middle Cerebral Artery/metabolism
- Infarction, Middle Cerebral Artery/pathology
- Infarction, Middle Cerebral Artery/therapy
- Male
- Nerve Tissue Proteins/biosynthesis
- Nerve Tissue Proteins/genetics
- Neuroglobin
- Neuroprotective Agents/pharmacology
- RNA, Messenger/metabolism
- Rats, Sprague-Dawley
- Time Factors
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Affiliation(s)
- Xue Song
- Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical UniversityChongqing, 400016, China
| | - Rui Xu
- Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical UniversityChongqing, 400016, China
| | - Fei Xie
- Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical UniversityChongqing, 400016, China
| | - Haiyuan Zhu
- Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical UniversityChongqing, 400016, China
| | - Ji Zhu
- Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical UniversityChongqing, 400016, China
| | - Xin Wang
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical SchoolBoston, Massachusetts 02115, USA
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Di Pietro V, Lazzarino G, Amorini AM, Tavazzi B, D'Urso S, Longo S, Vagnozzi R, Signoretti S, Clementi E, Giardina B, Lazzarino G, Belli A. Neuroglobin expression and oxidant/antioxidant balance after graded traumatic brain injury in the rat. Free Radic Biol Med 2014; 69:258-64. [PMID: 24491879 DOI: 10.1016/j.freeradbiomed.2014.01.032] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/07/2014] [Accepted: 01/24/2014] [Indexed: 11/29/2022]
Abstract
Neuroglobin is a neuron-specific hexacoordinated globin capable of binding various ligands, including O2, NO, and CO, the biological function of which is still uncertain. Various studies seem to indicate that neuroglobin is a neuroprotective agent when overexpressed, acting as a potent inhibitor of oxidative and nitrosative stress. In this study, we evaluated the pathophysiological response of the neuroglobin gene and protein expression in the cerebral tissue of rats sustaining traumatic brain injury of differing severity, while simultaneously measuring the oxidant/antioxidant balance. Two levels of trauma (mild and severe) were induced in anesthetized animals using the weight-drop model of diffuse axonal injury. Rats were then sacrificed at 6, 12, 24, 48, and 120 h after traumatic brain injury, and the gene and protein expression of neuroglobin and the concentrations of malondialdehyde (as a parameter representative of reactive oxygen species-mediated damage), nitrite + nitrate (indicative of NO metabolism), ascorbate, and glutathione (GSH) were determined in the brain tissue. Results indicated that mild traumatic brain injury, although causing a reversible increase in oxidative/nitrosative stress (increase in malondialdehyde and nitrite + nitrate) and an imbalance in antioxidants (decrease in ascorbate and GSH), did not induce any change in neuroglobin. Conversely, severe traumatic brain injury caused an over nine- and a fivefold increase in neuroglobin gene and protein expression, respectively, as well as a remarkable increase in oxidative/nitrosative stress and depletion of antioxidants. The results of this study, showing a lack of effect in mild traumatic brain injury as well as asynchronous time course changes in neuroglobin expression, oxidative/nitrosative stress, and antioxidants in severe traumatic brain injury, do not seem to support the role of neuroglobin as an endogenous neuroprotective antioxidant agent, at least under pathophysiological conditions.
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Affiliation(s)
- Valentina Di Pietro
- Neurotrauma and Neurodegeneration Section, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Giacomo Lazzarino
- Institute of Biochemistry and Clinical Biochemistry, Catholic University of Rome, Rome, Italy
| | - Angela Maria Amorini
- Institute of Biochemistry and Clinical Biochemistry, Catholic University of Rome, Rome, Italy
| | - Barbara Tavazzi
- Institute of Biochemistry and Clinical Biochemistry, Catholic University of Rome, Rome, Italy
| | - Serafina D'Urso
- Department of Biology, Geology, and Environmental Sciences, Division of Biochemistry and Molecular Biology, University of Catania, 95125 Catania, Italy
| | - Salvatore Longo
- Institute of Biochemistry and Clinical Biochemistry, Catholic University of Rome, Rome, Italy
| | - Roberto Vagnozzi
- Department of Biomedicine and Prevention, Section of Neurosurgery, University of Rome Tor Vergata, Rome, Italy
| | - Stefano Signoretti
- Division of Neurosurgery, Department of Neurosciences, Head and Neck Surgery, S. Camillo Hospital, Rome, Italy
| | - Elisabetta Clementi
- CNR Institute of "Chimica del riconoscimento molecolare," Catholic University of Rome, Rome, Italy
| | - Bruno Giardina
- Institute of Biochemistry and Clinical Biochemistry, Catholic University of Rome, Rome, Italy
| | - Giuseppe Lazzarino
- Department of Biology, Geology, and Environmental Sciences, Division of Biochemistry and Molecular Biology, University of Catania, 95125 Catania, Italy.
| | - Antonio Belli
- Neurotrauma and Neurodegeneration Section, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
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Singh S, Zhuo M, Gorgun FM, Englander EW. Overexpressed neuroglobin raises threshold for nitric oxide-induced impairment of mitochondrial respiratory activities and stress signaling in primary cortical neurons. Nitric Oxide 2013; 32:21-8. [PMID: 23587847 PMCID: PMC3816961 DOI: 10.1016/j.niox.2013.03.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 03/25/2013] [Accepted: 03/29/2013] [Indexed: 02/06/2023]
Abstract
Surges of nitric oxide compromise mitochondrial respiration primarily by competitive inhibition of oxygen binding to cytochrome c oxidase (complex IV) and are particularly injurious in neurons, which rely on oxidative phosphorylation for all their energy needs. Here, we show that transgenic overexpression of the neuronal globin protein, neuroglobin, helps diminish protein nitration, preserve mitochondrial function and sustain ATP content of primary cortical neurons challenged by extended nitric oxide exposure. Specifically, in transgenic neurons, elevated neuroglobin curtailed nitric oxide-induced alterations in mitochondrial oxygen consumption rates, including baseline oxygen consumption, consumption coupled with ATP synthesis, proton leak and spare respiratory capacity. Concomitantly, activation of genes involved in sensing and responding to oxidative/nitrosative stress, including the early-immediate c-Fos gene and the phase II antioxidant enzyme, heme oxygenase-1, was diminished in neuroglobin-overexpressing compared to wild-type neurons. Taken together, these differences reflect a lesser insult produced by similar concentrations of nitric oxide in neuroglobin-overexpressing compared to wild-type neurons, suggesting that abundant neuroglobin buffers nitric oxide and raises the threshold of nitric oxide-mediated injury in neurons.
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Affiliation(s)
- Shilpee Singh
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
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Tian SF, Yang HH, Xiao DP, Huang YJ, He GY, Ma HR, Xia F, Shi XC. Mechanisms of neuroprotection from hypoxia-ischemia (HI) brain injury by up-regulation of cytoglobin (CYGB) in a neonatal rat model. J Biol Chem 2013; 288:15988-6003. [PMID: 23585565 PMCID: PMC3668754 DOI: 10.1074/jbc.m112.428789] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 04/10/2013] [Indexed: 02/05/2023] Open
Abstract
This study was designed to investigate the expression profile of CYGB, its potential neuroprotective function, and underlying molecular mechanisms using a model of neonatal hypoxia-ischemia (HI) brain injury. Cygb mRNA and protein expression were evaluated within the first 36 h after the HI model was induced using RT-PCR and Western blotting. Cygb mRNA expression was increased at 18 h in a time-dependent manner, and its level of protein expression increased progressively in 24 h. To verify the neuroprotective effect of CYGB, a gene transfection technique was employed. Cygb cDNA and shRNA delivery adenovirus systems were established (Cygb-cDNA-ADV and Cygb-shRNA-ADV, respectively) and injected into the brains of 3-day-old rats 4 days before they were induced with HI treatment. Rats from different groups were euthanized 24 h post-HI, and brain samples were harvested. 2,3,5-Triphenyltetrazolium chloride, TUNEL, and Nissl staining indicated that an up-regulation of CYGB resulted in reduced acute brain injury. The superoxide dismutase level was found to be dependent on expression of CYGB. The Morris water maze test in 28-day-old rats demonstrated that CYGB expression was associated with improvement of long term cognitive impairment. Studies also demonstrated that CYGB can up-regulate mRNA and protein levels of VEGF and increase both the density and diameter of the microvessels but inhibits activation of caspase-2 and -3. Thus, this is the first in vivo study focusing on the neuroprotective role of CYGB. The reduction of neonatal HI injury by CYGB may be due in part to antioxidant and antiapoptotic mechanisms and by promoting angiogenesis.
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Affiliation(s)
- Shu-Feng Tian
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Han-Hua Yang
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Dan-Ping Xiao
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Yue-Jun Huang
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Gu-Yu He
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Hai-Ran Ma
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Fang Xia
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
| | - Xue-Chuan Shi
- From the Department of Pediatrics, the Second Affiliated Hospital, Shantou University Medical College, North Section of Dong-xia Road, Shantou, Guangdong 515041, China
- To whom correspondence should be addressed. Tel.: 86-754-88915666; Fax: 86-754-88346543; E-mail:
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Li Z, Deng X, Xu J, Lian W. [Protective effects of PEG modified recombinant cytoglobin on acute liver injury in mice]. Sheng Wu Gong Cheng Xue Bao 2012; 28:1227-1235. [PMID: 23311137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
To investigate the protective effect of polyethylene glycol (PEG) modified recombinant cytoglobin (PEG-rCygb) on acute liver damage in mice. The acute liver injury model of KM mice was induced by CCl4 and then treated with PEG-rCygb, The liver and blood samples were collected for biochemical and histopathological analysis. The results showed that PEG-rCygb reduced the liver mass index and decreased significantly the levels of alanine amiotransferase (AST) and aspartate transaminase (ALT) in mouse serum. In liver tissues, the content of malondialdehyde (MDA) was decreased, whereas the content of glutathione (GSH) was increased in PEG-rCygb treated group. PEG-rCygb also elevated the activities of total super oxidedismutase (T-SOD) and catalase (CAT) in liver tissues. HE staining of liver tissue slices revealed that PEG-rCygb relieved fatty degeneration of liver, decreased inflammatory factors and reduced liver cell injury. Further in vitro experiments indicated that the protective effects of PEG-rCygb on hepatic stellate cell (HSC) against H2O2 were enhanced compared with that of rCygb. All results indicated that the PEG-rCygb promoted oxygen free radical scavenging ability and prevented acute liver injury in KM mice induced by CCl4.
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Affiliation(s)
- Zhaofa Li
- Institute of Molecular Medicine, Huaqiao University, Quanzhou 362021, Fujian, China.
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Mogal AP, Watson MA, Ozsolak F, Salavaggione L, Humphrey PA. Gene expression profiles and differential cytoglobin expression in atrophy and adenocarcinoma of the prostate. Prostate 2012; 72:931-7. [PMID: 22025306 DOI: 10.1002/pros.21494] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Accepted: 09/01/2011] [Indexed: 11/07/2022]
Abstract
BACKGROUND Proliferative inflammatory atrophy (PIA) has been proposed as a potential precursor for prostate cancer. The precise molecular abnormalities in prostatic atrophy compared to high-grade prostatic intraepithelial neoplasia (HGPIN) and carcinoma have not been fully defined. METHODS We utilized laser capture microdissection and microarray analysis to characterize cells of PIA, HGPIN, invasive prostatic carcinoma, and non-atrophic benign prostatic epithelium (NABE). Cytoglobin was selected for immunohistochemistry (IHC) validation. IHC stains were evaluated for proportion of positive glands, and intensity of cytoglobin staining. An immunoreactive score (IR score) was determined as the product of the percentage of positive staining and intensity. RESULTS Microarray analysis revealed probe sets that separated the microdissected cell types. Several genes showed overlapping expression patterns between PIA and PIN, and HGPIN and invasive carcinoma. Cytoglobin protein expression was detected in 57/93 (61%) of NABE and BPH cases, 92/93 atrophy (99%), 3/34 (9%) of PIN, and 23/61 carcinoma (37%) samples. The highest IHC scores were calculated for atrophy foci. A subset (33%) of atrophy cases showed the same low-cytoglobin expression level as PIN and carcinoma. CONCLUSIONS Prostatic epithelium can be stratified into normal, atrophic, PIN, and invasive carcinoma categories based on differential genetic signatures. Cytoglobin, a protein that can be induced in response to oxidative stress, was elevated in most atrophy foci, suggesting hypoxic, and/or oxidative damage. The lower level of cytoglobin seen in neoplastic cells and 33% of atrophy foci may indicate a shared susceptibility to oxidative damage for this subset of atrophy cases and prostatic neoplasia.
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Affiliation(s)
- Ashish P Mogal
- Department of Pathology and Immunology, Washington University, St. Louis, Missouri, USA.
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Lee HM, Greeley GH, Englander EW. Transgenic overexpression of neuroglobin attenuates formation of smoke-inhalation-induced oxidative DNA damage, in vivo, in the mouse brain. Free Radic Biol Med 2011; 51:2281-7. [PMID: 22001746 PMCID: PMC3241998 DOI: 10.1016/j.freeradbiomed.2011.09.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 09/16/2011] [Accepted: 09/20/2011] [Indexed: 12/15/2022]
Abstract
Acute inhalation of combustion smoke causes neurological deficits in survivors. Inhaled smoke includes carbon monoxide, noxious gases, and a hypoxic environment, which disrupt oxygenation and generate free radicals. To replicate a smoke-inhalation scenario, we developed an experimental model of acute exposure to smoke for the awake mouse/rat and detected induction of biomarkers of oxidative stress. These include inhibition of mitochondrial respiratory complexes and formation of oxidative DNA damage in the brain. DNA damage is likely to contribute to neuronal dysfunction and progression of brain injury. In the search for strategies to attenuate the smoke-initiated brain injury, we produced a transgenic mouse overexpressing the neuronal globin protein neuroglobin. Neuroglobin was neuroprotective in diverse models of ischemic/hypoxic/toxic brain injuries. Here, we report lesser inhibition of respiratory complex I and reduced formation of smoke-induced DNA damage in neuroglobin transgenic compared to wild-type mouse brain. DNA damage was assessed using the standard comet assay, as well as a modified comet assay done in conjunction with an enzyme that excises oxidized guanines that form readily under conditions of oxidative stress. Both comet assays revealed that overexpressed neuroglobin attenuates the formation of oxidative DNA damage, in vivo, in the brain. These findings suggest that elevated neuroglobin exerts neuroprotection, in part, by decreasing the impact of acute smoke inhalation on the integrity of neuronal DNA.
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Affiliation(s)
- Heung Man Lee
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
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Abstract
The progress of immunoisolation as a treatment for diabetes has been hampered by the diminished long term viability of islets within the immunoisolation device. Chronic hypoxia is greatly responsible for islet cell death within an immunoisolation device and remains an obstacle to the success of this form of islet transplantation. In order to address this problem, isolated rat islets were transfected with a plasmid encoding cytoglobin, an intracellular oxygen binding protein. Untreated or transfected islets were placed in polyacrylonitrile-polyvinychloride hollow fiber and implanted beneath the hepatic capsule in streptozotocin-diabetic rats. Fasting blood glucose was used as an indicator of islet survival and function. Rats receiving fibers containing transfected islets remained normoglycemic through the 60 day trial. Untreated islets failed within two weeks after implantation resulting in elevated blood glucose in the recipient. The fibers were recovered and tested for insulin content. Cytoglobin promoted islet cell survival and insulin synthesis and secretion. The induction of cytoglobin in islets may reduce cell loss from chronic hypoxia and may be a useful method to improve the feasibility of immunoisolation as an islet transplantation modality.
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Affiliation(s)
- John I Stagner
- Robley Rex Department of Veterans Affairs Medical Center, Louisville, KY, USA.
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Abstract
BACKGROUND AND PURPOSE We investigated whether neuroglobin, a neuronal protein that protects neurons from hypoxic-ischemic injury, is upregulated in ischemic stroke. METHODS Neuroglobin immunoreactivity was measured in brain tissue from control subjects and patients with ischemic stroke. RESULTS Neuroglobin was detected in several brain areas, and its expression was increased in the cortical peri-infarct region after stroke. CONCLUSIONS Ischemic stroke increases expression of the neuroprotective protein neuroglobin, suggesting neuroglobin may represent a novel target for stroke therapy.
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Khatami S, Dehboneh SR, Sadeghi S, Mirzazadeh R, Saeedi P, Bayat P, Najmabadi H, Zeinali S, Akbari MT, Ardjmand M, Amirkhani A. Globin Chain Synthesis is a Useful Complementary Tool in the Differential Diagnosis of Thalassemias. Hemoglobin 2009; 31:333-41. [PMID: 17654070 DOI: 10.1080/03630260701462006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The present study aimed at differentiating rare types of heterozygous beta-thalassemia (thal) with normal Hb A(2) values from alpha-thal in Iranian carriers by globin chain synthesis in addition to other hematological parameters. Our study groups consisted of 51 normal subjects, 24 heterozygous beta- thalassemic subjects with high Hb A(2), 62 alpha-thal-2 subjects, 34 alpha-thal-1 subjects, six Hb H disease thalassemic subjects, 14 silent beta-thal subjects with normal Hb A(2) values, five deltabeta-thal subjects and two subjects with an association of alpha- and deltabeta-thal (total = 198). Analysis of globin chains was performed by high performance liquid chromatography (HPLC). The results showed that the alpha/beta ratio averages were close to the ones in the published literature, but with a greater standard deviation and a wider range. Globin chain synthesis (GCS) could be valuable in differentiating between microcytosis produced by silent beta-thal (heterozygous beta-thal with a normal Hb A(2) level) and that caused by alpha-thal. Since the complex genotype/phenotype relationship can lead to diagnostic difficulties, GCS cannot be used as the only diagnostic tool for thalassemia carrier detection. Therefore, a combination of different tests for each patient is required.
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Affiliation(s)
- Shohreh Khatami
- Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
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Kramer S, Viljoen E, Becker D, Zail SS, Metz J. The relationship between haem and globin synthesis by erythroid precursors in refractory normoblastic anaemia. Scand J Haematol 2009; 6:293-302. [PMID: 5364335 DOI: 10.1111/j.1600-0609.1969.tb02413.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Kalamaras A, Chassanidis C, Samara M, Papadakis MN, Vagena A, Aleporou-Marinou V, Patrinos GP, Kollia P. Compound heterozygosity of non-deletional hereditary persistence of fetal hemoglobin and deltabeta-thalassemia. Am J Hematol 2008; 83:760. [PMID: 18615450 DOI: 10.1002/ajh.21243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Pallister J, Goldie S, Coupar B, Shiell B, Michalski WP, Siddon N, Hyatt A. Bohle iridovirus as a vector for heterologous gene expression. J Virol Methods 2007; 146:419-23. [PMID: 17904650 DOI: 10.1016/j.jviromet.2007.08.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 08/13/2007] [Accepted: 08/22/2007] [Indexed: 11/28/2022]
Abstract
The large double-stranded DNA (ds DNA) viruses were among the first to be used to construct recombinant viruses, but to date this has not been achieved with any members of the ds DNA virus family, Iridoviridae. We identified a non-essential gene, the viral homologue of eukaryotic initiation factor 2alpha (eIF-2alpha), in Bohle iridovirus (BIV, genus Ranavirus). A recombinant BIV was constructed with the neomycin resistance gene and the Bufo marinus (cane toad) adult globin gene inserted into the BIV eIF-2alpha region. Adult globin expressed by the virus was detected on western blot, demonstrating that foreign genes can be expressed by the recombinant BIV in vitro and suggesting the possibility of using a recombinant BIV in the biological control of cane toads.
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Affiliation(s)
- Jackie Pallister
- CSIRO Livestock Industries, Australian Animal Health Laboratory, 5 Portarlington Road, Geelong, Victoria 3220, Australia.
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Abstract
To delineate the relationship between epigenetic modifications and hemoglobin switching, we compared the pattern of histone acetylation and pol II binding across the beta-globin locus at fetal and adult stages of human development. To make this comparison possible, we introduced an external control into experimental samples in chromatin immunoprecipitation (ChIP) assays. Using this common standard, we found that the locus control region (LCR) was acetylated to the same level at all stages, whereas acetylation levels at the individual gene regions correlated with the state of transcription. In the active genes, the promoters were less acetylated compared with the coding regions. Furthermore, all globin promoters were acetylated to a similar level irrespective of the state of transcription. However, after correction for the loss of nucleosomes, the level of acetylation per histone at the active gamma and beta promoters was 5- to 7-fold greater than that at the inactive epsilon promoter. Although the histone acetylation level within the LCR was developmentally stable, pol II binding in fetal erythroblasts was 2- to 3-fold greater than that in adult erythroblasts. These results demonstrate that dynamic changes in histone acetylation and pol II take place as the human beta-globin gene region undergoes its developmental switches.
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Affiliation(s)
- Wenxuan Yin
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, 98195, USA
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Gardiner MR, Gongora MM, Grimmond SM, Perkins AC. A global role for zebrafish klf4 in embryonic erythropoiesis. Mech Dev 2007; 124:762-74. [PMID: 17709232 DOI: 10.1016/j.mod.2007.06.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 06/06/2007] [Accepted: 06/18/2007] [Indexed: 01/21/2023]
Abstract
There are two waves of erythropoiesis, known as primitive and definitive waves in mammals and lower vertebrates including zebrafish. The founding member of the Kruppel-like factor (KLF) family of CACCC-box binding proteins, EKLF/Klf1, is essential for definitive erythropoiesis in mammals but only plays a minor role in primitive erythropoiesis. Morpholino knockdown experiments have shown a role for zebrafish klf4 in primitive erythropoiesis and hatching gland formation. In order to generate a global understanding of how klf4 might influence gene expression and differentiation, we have performed expression profiling of klf4 morphants, and then performed validation of many putative target genes by qRT-PCR and whole mount in situ hybridization. We found a critical role for klf4 in embryonic globin, heme synthesis and hatching gland gene expression. In contrast, there was an increase in expression of definitive hematopoietic specific genes such as larval globin genes, runx1 and c-myb from 24 hpf, suggesting a selective role for klf4 in primitive rather than definitive erythropoiesis. In addition, we show klf4 preferentially binds CACCC box elements in the primitive zebrafish beta-like globin gene promoters. These results have global implications for primitive erythroid gene regulation by KLF-CACCC box interactions.
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Affiliation(s)
- M R Gardiner
- Institute for Molecular Bioscience, University of Queensland, Australia
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Winichagoon P, Svasti S, Winichagoon P, Chitchumroonchokchai C, Fucharoen S. Expression of betaE and gamma-globin genes in infants heterozygous for hemoglobin E and double heterozygous for hemoglobin E and alpha-thalassemia. Haematologica 2007; 92:702-3. [PMID: 17488699 DOI: 10.3324/haematol.10930] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
This study described the expression of betaE-globin in newborns heterozygous for HbE. Despite the lower level of HbE, the pattern of betaE-globin gene expression was similar to betaA-globin because the increase in HbE and HbA reached the peak level at the same time. A delayed decline of HbF was observed.
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Chan PK, Ma ESK, Philipsen S, Tan-Un KC. The study of sequence configuration and functional impact of the (AC)n(AT)xTy motif in human beta-globin gene promoter. Am J Hematol 2007; 82:342-8. [PMID: 17133428 DOI: 10.1002/ajh.20836] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In this report we examine the (AC)n(AT)xTy motif residing -530 bp 5' upstream of the beta-globin gene in Chinese thalassaemic patients. This motif is a putative binding site for a repressor protein, termed beta protein 1 (BP1) (Berg et al., Nucleic Acids Res 1989;17:8833-8852). Variations in the (AC)n(AT)xTy repeats affect the binding affinity of BP1, thereby altering the expression of the beta-globin gene. Eight different configurations of this repeat motif are identified in our population of Chinese beta-thalassaemia patients. A (AC)3(AT)7T5 motif was identified among these thalassaemia patients and its influence in beta-globin gene expression was studied using stable transfection assay in murine erythroleukemia (MEL) cells. Our data demonstrated that the (AC)3(AT)7T5 motif has a moderately strong repressor effect on the expression of the cis-linked beta-globin gene. The high affinity of BP1 for this motif may result in the suppression of the transcription of the beta-globin gene (Berg et al., Am J Hematol 1991;36:42-47). We postulate that silencer elements in the beta-globin promoter play an important role in modifying the clinical presentation of the disease.
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Affiliation(s)
- P K Chan
- Department of Zoology, Kadoorie Biological Science Building, The University of Hong Kong, Hong Kong SAR, People's Republic of China
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Tanabe O, McPhee D, Kobayashi S, Shen Y, Brandt W, Jiang X, Campbell AD, Chen YT, Chang CS, Yamamoto M, Tanimoto K, Engel JD. Embryonic and fetal beta-globin gene repression by the orphan nuclear receptors, TR2 and TR4. EMBO J 2007; 26:2295-306. [PMID: 17431400 PMCID: PMC1864974 DOI: 10.1038/sj.emboj.7601676] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Accepted: 03/12/2007] [Indexed: 11/09/2022] Open
Abstract
The TR2 and TR4 orphan nuclear receptors comprise the DNA-binding core of direct repeat erythroid definitive, a protein complex that binds to direct repeat elements in the embryonic and fetal beta-type globin gene promoters. Silencing of both the embryonic and fetal beta-type globin genes is delayed in definitive erythroid cells of Tr2 and Tr4 null mutant mice, whereas in transgenic mice that express dominant-negative TR4 (dnTR4), human embryonic epsilon-globin is activated in primitive and definitive erythroid cells. In contrast, human fetal gamma-globin is activated by dnTR4 only in definitive, but not in primitive, erythroid cells, implicating TR2/TR4 as a stage-selective repressor. Forced expression of wild-type TR2 and TR4 leads to precocious repression of epsilon-globin, but in contrast to induction of gamma-globin in definitive erythroid cells. These temporally specific, gene-selective alterations in epsilon- and gamma-globin gene expression by gain and loss of TR2/TR4 function provide the first genetic evidence for a role for these nuclear receptors in sequential, gene-autonomous silencing of the epsilon- and gamma-globin genes during development, and suggest that their differential utilization controls stage-specific repression of the human epsilon- and gamma-globin genes.
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Affiliation(s)
- Osamu Tanabe
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - David McPhee
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Shoko Kobayashi
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Yannan Shen
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - William Brandt
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Xia Jiang
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Andrew D Campbell
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Yei-Tsung Chen
- Departments of Pathology, Urology, Radiation Oncology, University of Rochester Medical Center, Rochester, NY, USA
| | - Chawn shang Chang
- Departments of Pathology, Urology, Radiation Oncology, University of Rochester Medical Center, Rochester, NY, USA
| | | | - Keiji Tanimoto
- Centre for TARA, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - James Douglas Engel
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200, USA. Tel.: +1 734 615 7509; Fax: +1 734 763 1166; E-mail:
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Kooren J, Palstra RJ, Klous P, Splinter E, von Lindern M, Grosveld F, de Laat W. Beta-globin active chromatin Hub formation in differentiating erythroid cells and in p45 NF-E2 knock-out mice. J Biol Chem 2007; 282:16544-52. [PMID: 17428799 DOI: 10.1074/jbc.m701159200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Expression of the beta-globin genes proceeds from basal to exceptionally high levels during erythroid differentiation in vivo. High expression is dependent on the locus control region (LCR) and coincides with more frequent LCR-gene contacts. These contacts are established in the context of an active chromatin hub (ACH), a spatial chromatin configuration in which the LCR, together with other regulatory sequences, loops toward the active beta-globin-like genes. Here, we used recently established I/11 cells as a model system that faithfully recapitulates the in vivo erythroid differentiation program to study the molecular events that accompany and underlie ACH formation. Upon I/11 cell induction, histone modifications changed, the ACH was formed, and the beta-globin-like genes were transcribed at rates similar to those observed in vivo. The establishment of frequent LCR-gene contacts coincided with a more efficient loading of polymerase onto the beta-globin promoter. Binding of the transcription factors GATA-1 and EKLF to the locus, although previously shown to be required, was not sufficient for ACH formation. Moreover, we used knock-out mice to show that the erythroid transcription factor p45 NF-E2, which has been implicated in beta-globin gene regulation, is dispensable for beta-globin ACH formation.
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Affiliation(s)
- Jurgen Kooren
- Department of Cell Biology, Erasmus Medical Center, P. O. Box 2040, 3000 CA Rotterdam, The Netherlands
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Cohen-Barak O, Erickson DT, Badowski MS, Fuchs DA, Klassen CL, Harris DT, Brilliant MH. Stem cell transplantation demonstrates that Sox6 represses εy globin expression in definitive erythropoiesis of adult mice. Exp Hematol 2007; 35:358-67. [PMID: 17309816 DOI: 10.1016/j.exphem.2006.11.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Revised: 11/03/2006] [Accepted: 11/16/2006] [Indexed: 11/22/2022]
Abstract
Sox6, a member of the Sox transcription factor family, is essential for the silencing of epsilon y globin gene expression in definitive erythropoiesis of mice. Homozygous Sox6-null mice are neonatally lethal, precluding analysis at later stages. We created adult mice that are deficient in Sox6 specifically in hematopoietic tissues by transplanting embryonic liver stem cells from Sox6-deficient mice into lethally irradiated congenic wild-type adult mice. The mice receiving mutant stem cells (mutant engrafted) showed high expression levels of epsilon y in bone marrow, spleen, and circulating blood compared with mice receiving wild-type and heterozygous stem cells (control engrafted). The level of expression of epsilon y in circulating blood was directly correlated with the percentage of successful mutant donor cell engraftment. Additionally, the mutant engrafted adult mice showed an increase in erythroid precursor cells in bone marrow, spleen, and blood. Thus, Sox6 continues to function as a major regulator of epsilon y in adult definitive erythropoiesis and is required for normal erythrocyte maturation. Therefore, Sox6 may provide a novel therapeutic target by reactivating epsilon y in patients with hemoglobinopathies such as sickle cell anemia and beta-thalassemia.
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Affiliation(s)
- Orit Cohen-Barak
- Department of Pediatrics, University of Arizona, College of Medicine, Tucson, AZ 85724, USA
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Ramachandran K, van Wert J, Gopisetty G, Singal R. Developmentally Regulated Demethylase Activity Targeting the βA-Globin Gene in Primary Avian Erythroid Cells. Biochemistry 2007; 46:3416-22. [PMID: 17315984 DOI: 10.1021/bi0620813] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Differential expression of globin genes has provided an interesting model system for better understanding commonly inherited diseases such as thalassemia. In the avian beta-type globin cluster (5'-rho-betaH-betaA-epsilon-3'), silencing of the embryonic rho-globin gene occurs concomitantly with the activation of the adult betaA-globin gene during embryonic development. DNA methylation is a dynamic process that regulates gene expression. We observed a progressive loss of methylation of betaA-globin gene, during avian embryonic development that was concurrent with the expression of the gene. The promoter and exon 1 regions of the template strand were completely demethylated, whereas residual methylation was retained in exons 2 and 3. Using a modified methylation-sensitive single-nucleotide primer extension (MS-SNuPE) assay, we observed stage-specific demethylase activity in the nuclear extracts of chicken red cells; activity in 5-, 8-, and 11-day-old erythroid cell nuclear extracts was 6, 76, and 24%, respectively. The demethylase targeted both hemimethylated and fully methylated substrates. Our findings demonstrate stage-specific demethylase activity in nuclear extracts from primary chicken erythroid cells that could target the fully methylated promoter of a developmentally regulated native gene.
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35
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Wolf Y, Pritz S, Abes S, Bienert M, Lebleu B, Oehlke J. Structural requirements for cellular uptake and antisense activity of peptide nucleic acids conjugated with various peptides. Biochemistry 2007; 45:14944-54. [PMID: 17154532 DOI: 10.1021/bi0606896] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Peptide nucleic acids (PNAs) have shown great promise as potential antisense drugs; however, poor cellular delivery limits their applications. Improved delivery into mammalian cells and enhanced biological activity of PNAs have been achieved by coupling to cell-penetrating peptides (CPPs). Structural requirements for the shuttling ability of these peptides as well as structural properties of the conjugates such as the linker type and peptide position remained controversial, so far. In the present study an 18mer PNA targeted to the cryptic splice site of a mutated beta-globin intron 2, which had been inserted into a luciferase reporter gene coding sequence, was coupled to various peptides. As the peptide lead we used the cell-penetrating alpha-helical amphipathic peptide KLAL KLAL KAL KAAL KLA-NH2 [model amphipathic peptide (MAP)] which was varied with respect to charge and structure-forming properties. Furthermore, the linkage and the localization of the attached peptide (C- vs N-terminal) were modified. Positive charge as well as helicity and amphipathicity of the KLA peptide was all required for efficient dose-dependent correction of aberrant splicing. The highest antisense effect was reached within 4 h without any transfection agent. Stably linked conjugates were also efficient in correction of aberrant splicing, suggesting that a cleavable disulfide bond between CPP and PNA is clearly not essential. Moreover, the placement of the attached peptide turned out to be crucial for attaining antisense activity. Coadministration of endosome disrupting agents such as chloroquine or Ca2+ significantly increased the splicing correction efficiency of some conjugates, indicating the predominant portion to be sequestered in vesicular compartments.
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Affiliation(s)
- Yvonne Wolf
- Leibniz-Institute of Molecular Pharmacology, Robert-Rössle-Strasse 10, D-13125 Berlin, Germany.
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36
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Zhang CM, Feng ZC. [Matrine-induced gamma-globin synthesis in K562 cells]. Nan Fang Yi Ke Da Xue Xue Bao 2007; 27:215-8. [PMID: 17355941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
OBJECTIVE To study the effects of matrine on gamma-globin synthesis in K562 cells in vitro. METHODS Benzidine staining was used to study the dose- and time-dependent effects of matrine on hemoglobin synthesis in K562 cells, and Western blotting was performed to determine the level of hemoglobin F(alpha(2)gamma(2)). RESULTS Benzidine staining showed that K562 cells treated with matrine of 0.1 mg/ml had a positivity rate for benzidine (BZ%) of 15.67% at 96 h after the treatment, and Western blotting indicated increased synthesis of hemoglobin F. CONCLUSION Matrine can induce gamma-globin synthesis and increase hemoglobin F level in K562 cells, the effect of which resembles that of sodium butyrate.
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Affiliation(s)
- Cui-Mei Zhang
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China.
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37
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Abstract
PURPOSE OF REVIEW The beta-thalassemias and sickle cell anemia are severe congenital anemias for which there is presently no curative therapy other than allogeneic hematopoietic stem cell transplantation. This therapeutic option, however, is not available to most patients due to the lack of an HLA-matched bone marrow donor. The transfer of a regulated globin gene in autologous hematopoietic stem cells is therefore a highly attractive alternative treatment. This strategy, simple in principle, raises major challenges in terms of controlling transgene expression, which ideally should be erythroid specific, differentiation and stage restricted, elevated, position independent, and sustained over time. RECENT FINDINGS Using lentiviral vectors, May et al. demonstrated that an optimized combination of proximal and distal transcriptional control elements permits lineage-specific and elevated beta-globin expression in vivo, resulting in therapeutic hemoglobin production and correction of anemia in beta-thalassemic mice. Several groups have extended these findings to various models of beta-thalassemia and sickle cell disease. While the addition of the wild-type beta-globin gene is naturally suited for treating beta-thalassemia, several alternatives have been proposed for the treatment of sickle cell disease, using either gamma or mutant beta-globin gene addition, trans-splicing or RNA interference. SUMMARY These recent advances bode well for the clinical investigation of stem cell-based gene therapy in the severe hemoglobinopathies.
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Affiliation(s)
- Michel Sadelain
- Memorial Sloan-Kettering Cancer Center, New York 10021, USA.
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38
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Setton-Avruj CP, Musolino PL, Salis C, Alló M, Bizzozero O, Villar MJ, Soto EF, Pasquini JM. Presence of alpha-globin mRNA and migration of bone marrow cells after sciatic nerve injury suggests their participation in the degeneration/regeneration process. Exp Neurol 2006; 203:568-78. [PMID: 17126834 DOI: 10.1016/j.expneurol.2006.09.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Revised: 08/29/2006] [Accepted: 09/18/2006] [Indexed: 11/18/2022]
Abstract
We have previously reported that in the distal stump of ligated sciatic nerves, there is a change in the distribution of myelin basic protein (MBP) and P0 protein immunoreactivities. These results agreed with the studies of myelin isolated from the distal stump of animals submitted to ligation of the sciatic nerve, showing a gradual increase in a 14 kDa band with an electrophoretic mobility similar to that of an MBP isoform, among other changes. This band, which was resolved into two bands of 14 and 15 kDa using a 16% gel, was found to contain a mixture of MBP fragments and peptides with great homology with alpha- and beta-globins. In agreement with these results, we have demonstrated that the mRNA of alpha-globin is present in the proximal and distal stumps of the ligated nerve. It is also detected at very low levels in Schwann cells isolated from normal nerves. These results could be due to the presence of alpha- and/or beta-globin arising from immature cells of the erythroid series. Also, they could be present in macrophages, which spontaneously migrate to the injured nerve to promote the degradation of myelin proteins. Cells isolated from normal adult rat bone marrow which were injected intraortically were found to migrate to the injured area. These cells could contribute to the remyelination of the damaged area participating in the removal of myelin debris, through their transdifferentiation into Schwann cells or through their fusion with preexisting Schwann cells in the distal stump of the injured sciatic nerve.
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Affiliation(s)
- C P Setton-Avruj
- Department of Biological Chemistry and Institute of Biological and Physical Chemistry (IQUIFIB), School of Pharmacy and Biochemistry, University of Buenos Aires-CONICET, Junin 956, Buenos Aires, Argentina
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39
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Irenge LM, Robert A, Gala JL. Quantitative assessment of the transcriptional impact of mutations in the 3'untranslated region of the human beta-globin gene: application to the +1480 C-->G mutation. Haematologica 2006; 91:1563-4. [PMID: 17043018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2006] [Accepted: 09/12/2006] [Indexed: 05/12/2023] Open
Abstract
The +1480 C -->G mutation in the 3' untranslated region (UTR) of the human beta-globin gene has been associated with beta-thalassemia. A previously vali- dated in vitroexpression model used to assess the transcriptional impact of this 3'UTR mutation demonstrated that it has no effect on beta-globin gene expression.
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40
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Fibach E, Bianchi N, Borgatti M, Zuccato C, Finotti A, Lampronti I, Prus E, Mischiati C, Gambari R. Effects of rapamycin on accumulation of ?-, ?- and ?-globin mRNAs in erythroid precursor cells from ?-thalassaemia patients. Eur J Haematol 2006; 77:437-41. [PMID: 16939628 DOI: 10.1111/j.1600-0609.2006.00731.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We studied the effects of rapamycin on cultures of erythroid progenitors derived from the peripheral blood of 10 beta-thalassaemia patients differing widely with respect to their potential to produce foetal haemoglobin (HbF). For this, we employed the two-phase liquid culture procedure for growing erythroid progenitors, high performance liquid chromatography for analysis of HbF production and reverse transcription polymerase chain reaction for quantification of the accumulation of globin mRNAs. The results demonstrated that rapamycin induced an increase of HbF in cultures from all the beta-thalassaemia patients studied and an increase of their overall Hb content/cell. The inducing effect of rapamycin was restricted to gamma-globin mRNA accumulation, being only minor for beta-globin and none for alpha-globin mRNAs. The ability of rapamycin to preferentially increase gamma-globin mRNA content and production of HbF in erythroid precursor cells from beta-thalassaemia patients is of great importance as this agent (also known as sirolimus or rapamune) is already in clinical use as an anti-rejection agent following kidney transplantation. These data suggest that rapamycin warrants further evaluation as a potential therapeutic drug in beta-thalassaemia and sickle cell anaemia.
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Affiliation(s)
- Eitan Fibach
- Department of Haematology, Hadassah - Hebrew University Medical Centre, Jerusalem, Israel
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41
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Pace BS, Zein S. Understanding mechanisms of gamma-globin gene regulation to develop strategies for pharmacological fetal hemoglobin induction. Dev Dyn 2006; 235:1727-37. [PMID: 16607652 DOI: 10.1002/dvdy.20802] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The developmental regulation of gamma-globin gene expression has shaped research efforts to establish therapeutic modalities for individuals affected with sickle cell disease (SCD). Fetal hemoglobin (Hb F) synthesis is high at birth, followed by a decline to adult levels by 10 months of age. The expression of gamma-globin is controlled by a developmentally regulated transcriptional program that is recapitulated during normal erythropoiesis in the adult bone marrow. It is known that naturally occurring mutations in the gamma-gene promoters cause persistent Hb F synthesis after birth, which ameliorates symptoms in SCD by inhibiting hemoglobin S polymerization and vaso-occlusion. Several pharmacological agents have been identified over the past 2 decades that reactivate gamma-gene transcription through different cellular systems. We will review the progress made in our understanding of molecular mechanisms that control gamma-globin expression and insights gained from Hb F-inducing agents that act through signal transduction pathways.
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Affiliation(s)
- Betty S Pace
- University of Texas at Dallas, Department of Molecular and Cell Biology, Richardson, Texas 75083, USA.
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42
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Splinter E, Heath H, Kooren J, Palstra RJ, Klous P, Grosveld F, Galjart N, de Laat W. CTCF mediates long-range chromatin looping and local histone modification in the beta-globin locus. Genes Dev 2006; 20:2349-54. [PMID: 16951251 PMCID: PMC1560409 DOI: 10.1101/gad.399506] [Citation(s) in RCA: 546] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
CTCF (CCCTC-binding factor) binds sites around the mouse beta-globin locus that spatially cluster in the erythroid cell nucleus. We show that both conditional deletion of CTCF and targeted disruption of a DNA-binding site destabilize these long-range interactions and cause local loss of histone acetylation and gain of histone methylation, apparently without affecting transcription at the locus. Our data demonstrate that CTCF is directly involved in chromatin architecture and regulates local balance between active and repressive chromatin marks. We postulate that throughout the genome, relative position and stability of CTCF-mediated loops determine their effect on enhancer-promoter interactions, with gene insulation as one possible outcome.
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Affiliation(s)
- Erik Splinter
- Department of Cell Biology and Genetics, Erasmus Medical Center, 3000 DR Rotterdam, The Netherlands
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43
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Dumitriu B, Patrick MR, Petschek JP, Cherukuri S, Klingmuller U, Fox PL, Lefebvre V. Sox6 cell-autonomously stimulates erythroid cell survival, proliferation, and terminal maturation and is thereby an important enhancer of definitive erythropoiesis during mouse development. Blood 2006; 108:1198-207. [PMID: 16627753 DOI: 10.1182/blood-2006-02-004184] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
AbstractErythropoiesis, the essential process of hematopoietic stem cell development into erythrocytes, is controlled by lineage-specific transcription factors that determine cell fate and differentiation and by the hormone erythropoietin that stimulates cell survival and proliferation. Here we identify the Sry-related high-mobility-group (HMG) box transcription factor Sox6 as an important enhancer of definitive erythropoiesis. Sox6 is highly expressed in proerythroblasts and erythroblasts in the fetal liver, neonatal spleen, and bone marrow. Mouse fetuses and pups lacking Sox6 develop erythroid cells slowly and feature misshapen, short-lived erythrocytes. They compensate for anemia by elevating the serum level of erythropoietin and progressively enlarging their erythropoietic tissues. Erythroid-specific inactivation of Sox6 causes the same phenotype, demonstrating cell-autonomous roles for Sox6 in erythroid cells. Sox6 potentiates the ability of erythropoietin signaling to promote proerythroblast survival and has an effect additive to that of erythropoietin in stimulating proerythroblast and erythroblast proliferation. Sox6 also critically facilitates erythroblast and reticulocyte maturation, including hemoglobinization, cell condensation, and enucleation, and ensures erythrocyte cytoskeleton long-term stability. It does not control adult globin and erythrocyte cytoskeleton genes but acts by stabilizing filamentous actin (F-actin) levels. Sox6 thus enhances erythroid cell development at multiple levels and thereby ensures adequate production and quality of red blood cells.
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Affiliation(s)
- Bogdan Dumitriu
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH 44195, USA
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44
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Mammen PP, Shelton JM, Ye Q, Kanatous SB, McGrath AJ, Richardson JA, Garry DJ. Cytoglobin is a stress-responsive hemoprotein expressed in the developing and adult brain. J Histochem Cytochem 2006; 54:1349-61. [PMID: 16899760 PMCID: PMC3958125 DOI: 10.1369/jhc.6a7008.2006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Cytoglobin (Cygb) is a novel tissue hemoprotein relatively similar to myoglobin (Mb). Because Cygb shares several structural features with Mb, we hypothesized that Cygb functions in the modulation of oxygen and nitric oxide metabolism or in scavenging free radicals within a cell. In the present study we examined the spatial and temporal expression pattern of Cygb during murine embryogenesis. Using in situ hybridization, RT-PCR, and Northern blot analyses, limited Cygb expression was observed during embryogenesis compared with Mb expression. Cygb expression was primarily restricted to the central nervous system and neural crest derivatives during the latter stages of development. In the adult mouse, Cygb is expressed in distinct regions of the brain as compared with neuroglobin (Ngb), another globin protein, and these regions are responsive to oxidative stress (i.e., hippocampus, thalamus, and hypothalamus). In contrast to Ngb, Cygb expression in the brain is induced in response to chronic hypoxia (10% oxygen). These results support the hypothesis that Cygb is an oxygen-responsive tissue hemoglobin expressed in distinct regions of thenormoxic and hypoxic brain and may play a key role in the response of the brain to ahypoxic insult.
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Affiliation(s)
- Pradeep P.A. Mammen
- Departments of Internal Medicine University of Texas Southwestern Medical Center, Dallas, Texas
- Donald W. Reynolds Cardiovascular Clinical Research Center, University of Texas Southwestern Medical Center, Dallas, Texas
| | - John M. Shelton
- Departments of Internal Medicine University of Texas Southwestern Medical Center, Dallas, Texas
- Donald W. Reynolds Cardiovascular Clinical Research Center, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Qiu Ye
- Departments of Internal Medicine University of Texas Southwestern Medical Center, Dallas, Texas
| | - Shane B. Kanatous
- Departments of Internal Medicine University of Texas Southwestern Medical Center, Dallas, Texas
| | - Amanda J. McGrath
- Departments of Internal Medicine University of Texas Southwestern Medical Center, Dallas, Texas
| | - James A. Richardson
- Pathology University of Texas Southwestern Medical Center, Dallas, Texas
- Molecular Biology University of Texas Southwestern Medical Center, Dallas, Texas
| | - Daniel J. Garry
- Departments of Internal Medicine University of Texas Southwestern Medical Center, Dallas, Texas
- Molecular Biology University of Texas Southwestern Medical Center, Dallas, Texas
- Donald W. Reynolds Cardiovascular Clinical Research Center, University of Texas Southwestern Medical Center, Dallas, Texas
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45
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Han L, Lu J, Pan L, Wang X, Shao Y, Han S, Huang B. Histone acetyltransferase p300 regulates the transcription of human erythroid-specific 5-aminolevulinate synthase gene. Biochem Biophys Res Commun 2006; 348:799-806. [PMID: 16904069 DOI: 10.1016/j.bbrc.2006.07.147] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Accepted: 07/11/2006] [Indexed: 10/24/2022]
Abstract
Erythroid-specific 5-aminolevulinate synthase (ALAS2) catalyzes the rate-limiting step in heme biosynthesis of erythroid cells. Here, we show that treatment of erythroid K562 cells with HDAC inhibitors sodium butyrate or Trichostatin A gave rise to a significant increase in ALAS2 gene transcripts, with a concurrent increase in acetylation level of histone H4 at the ALAS2 gene promoter. Histone acetyltransferase p300 bound withALAS2 promoter and overexpression of p300 increased both the promoter reporter expression and endogenous mRNA level of ALAS2. Additionally, two functional Sp1 sites located in ALAS2 promoter were identified. Both of the GATA-1 sites and all the Sp1 sites at the ALAS2 promoter contributed to the transcription synergistic action with p300. These data implicated a close relationship between the acetylation modification of histone at the ALAS2 promoter and the regulation of this gene. Meanwhile, this work identified that ALAS2 is a novel target gene for p300/CBP action as histone acetyltransferases.
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Affiliation(s)
- Liping Han
- Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024, China
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46
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Schmidt-Kastner R, Haberkamp M, Schmitz C, Hankeln T, Burmester T. Neuroglobin mRNA expression after transient global brain ischemia and prolonged hypoxia in cell culture. Brain Res 2006; 1103:173-80. [PMID: 16796995 DOI: 10.1016/j.brainres.2006.05.047] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2006] [Revised: 05/09/2006] [Accepted: 05/16/2006] [Indexed: 11/18/2022]
Abstract
Neuroglobin is a nerve-specific respiratory protein that has been proposed to play an important role in the protection of brain neurons from ischemic and hypoxic injuries. Here, we investigated the regulation of neuroglobin expression after transient global ischemia in the rat brain using mRNA in situ hybridization and under hypoxic stress in cultured neuronal cell lines (PC12, HN33) by quantitative RT-PCR. While neuroglobin mRNA expression was significantly enhanced in cell culture after severe prolonged hypoxia (0-1% O2 for 24 h), we did not find any significant increases in neuroglobin mRNA levels in the rat brain after transient global ischemia. Vegf and Glut1 mRNAs showed increases in the hippocampus as expected. Therefore, it is unlikely that neuroglobin is instrumental in the acute response of neurons to hypoxic or ischemic insults, for which the mammalian brain is not adapted.
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Nilson DG, Sabatino DE, Bodine DM, Gallagher PG. Major erythrocyte membrane protein genes in EKLF-deficient mice. Exp Hematol 2006; 34:705-12. [PMID: 16728274 DOI: 10.1016/j.exphem.2006.02.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 02/16/2006] [Accepted: 02/21/2006] [Indexed: 11/18/2022]
Abstract
OBJECTIVES Mice deficient in the transcription factor erythroid Krüppel-like factor, KLF1 (EKLF) die approximately 14.5 days postcoitum of anemia, attributed to decreased expression of the beta-globin gene. The objectives of this study were to rescue EKLF-deficient embryos with mice expressing gamma-globin from beta-spectrin or ankyrin promoters and to characterize expression of the major erythrocyte membrane genes in EKLF-deficient cells. METHODS Transgenic beta-spectrin/gamma-globin or ankyrin/gamma-globin mice were bred onto EKLF-deficient and wild-type backgrounds. Animals were genotyped, gamma-globin mRNA levels measured, and hemoglobin electrophoresis performed. Steady-state mRNA levels and transcriptional rates of the major erythrocyte membrane protein genes were assayed. RESULTS beta-spectrin/gamma-globin or ankyrin/gamma-globin mice on EKLF-deficient and wild-type backgrounds had identical levels of gamma-globin mRNA, indicating EKLF-independence of these promoters. gamma-Globin expression improved globin chain imbalance, but hemolysis was not improved and no live-born EKLF-deficient/(A)gamma-globin mice were obtained. Circulating erythroid cells from EKLF-deficient/(A)gamma-globin embryos exhibited hemolysis reminiscent of that seen in patients with severe erythrocyte membrane defects. Levels of beta-spectrin, ankyrin, and band 3 mRNA, but not alpha-spectrin, were decreased in EKLF-deficient fetal liver RNA. In a run-on assay, levels of transcription of the ankyrin and band 3 genes were decreased in EKLF-deficient fetal liver nuclei. CONCLUSIONS These results indicate that the EKLF-responsive regions of the ankyrin and beta-spectrin genes are outside their promoters and that EKLF is necessary for full transcriptional activity of the ankyrin and band 3 genes; the results also provide additional evidence that defects in addition to beta-globin deficiency, including an abnormal erythrocyte membrane, contribute to the anemia and embryonic lethality in EKLF-deficient mice.
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Affiliation(s)
- Douglas G Nilson
- Hematopoiesis Section, Genetics and Molecular Biology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
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Grosveld F, Rodriguez P, Meier N, Krpic S, Pourfarzad F, Papadopoulos P, Kolodziej K, Patrinos GP, Hostert A, Strouboulis J. Isolation and characterization of hematopoietic transcription factor complexes by in vivo biotinylation tagging and mass spectrometry. Ann N Y Acad Sci 2006; 1054:55-67. [PMID: 16339652 DOI: 10.1196/annals.1345.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We have described the application of a simple biotinylation tagging approach for the direct purification of tagged transcription factor complexes, based on the use of artificial short peptide tags that are specifically and efficiently biotinylated by the bacterial BirA biotin ligase, which is co-expressed in cells with the tagged factor. We used this approach to initially characterize complexes formed by the hematopoietic transcription factor GATA-1 in erythroid cells. GATA-1 is essential for the erythroid differentiation, its functions encompassing upregulation of erythroid genes, repression of alternative transcription programs, and suppression of cell proliferation. However, it was not clear how all of these GATA-1 functions are mediated. Our work describes, for the first time, distinct GATA-1 interactions with the essential hematopoietic factor Gfi-1b, the repressive MeCP1 complex, and the chromatin remodeling ACF/WCRF complex, in addition to the known GATA-1/FOG-1 and GATA-1/TAL-1 complexes. We also provide evidence that distinct GATA-1 complexes are associated with specific GATA-1 functions in erythroid differentiation, for example, GATA-1/Gfi-1b with the suppression of cell proliferation and GATA-1/FOG-1/MeCP1 with the repression of other hematopoietic transcription programs. We next applied the biotinylation tag to Ldb-1, a known partner of GATA-1, and characterized a number of novel interaction partners that are essential in erythroid development, in particular, Eto-2, Lmo4, and CdK9. Last, we are in the process of applying the same technology to characterize the factors that are bound to the suppressed gamma-globin promoter in vivo.
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Affiliation(s)
- Frank Grosveld
- Department of Cell Biology, Erasmus University Medical Center, 50 Dr. Molewaterplein, 3015 GE Rotterdam, the Netherlands.
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Weiss MJ, Zhou S, Feng L, Gell DA, Mackay JP, Shi Y, Gow AJ. Role of alpha-hemoglobin-stabilizing protein in normal erythropoiesis and beta-thalassemia. Ann N Y Acad Sci 2006; 1054:103-17. [PMID: 16339656 DOI: 10.1196/annals.1345.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hemoglobin (Hb) synthesis is coordinated by homeostatic mechanisms to limit the accumulation of free alpha or beta subunits, which are cytotoxic. Alpha hemoglobin-stabilizing protein (AHSP) is an abundant erythroid protein that specifically binds free alphaHb, stabilizes its structure, and limits its ability to participate in chemical reactions that generate reactive oxygen species. Gene ablation studies in mice demonstrate that AHSP is required for normal erythropoiesis. AHSP-null erythrocytes are short-lived, contain Hb precipitates, and exhibit signs of oxidative damage. Loss of AHSP exacerbates beta-thalassemia in mice, indicating that altered AHSP expression or function could modify thalassemia phenotypes in humans, a topic that is beginning to be explored in clinical studies. We used biochemical, spectroscopic, and crystallographic methods to examine how AHSP stabilizes alphaHb. AHSP binds the G and H helices of alphaHb on a surface that largely overlaps with the alpha1-beta1 interface of HbA. This result explains previous findings that betaHb can competitively displace AHSP from alphaHb to form HbA tetramer. Remarkably, binding of AHSP to oxygenated alphaHb induces dramatic conformational changes and converts the heme-bound iron to an oxidized hemichrome state in which all six coordinate positions are occupied. This structure limits the reactivity of heme iron, providing a mechanism by which AHSP stabilizes alphaHb. These findings suggest a biochemical pathway through which AHSP might participate in normal Hb synthesis and modulate the severity of thalassemias. Moreover, understanding how AHSP stabilizes alphaHb provides a theoretical basis for new strategies to inhibit the damaging effects of free alphaHb that accumulates in beta-thalassemia.
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Affiliation(s)
- Mitchell J Weiss
- The Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Lai MI, Jiang J, Silver N, Best S, Menzel S, Mijovic A, Colella S, Ragoussis J, Garner C, Weiss MJ, Thein SL. alpha-Haemoglobin stabilising protein is a quantitative trait gene that modifies the phenotype of beta-thalassaemia. Br J Haematol 2006; 133:675-82. [PMID: 16704446 DOI: 10.1111/j.1365-2141.2006.06075.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
It has been suggested that altered levels or function of alpha-haemoglobin stabilising protein (AHSP), an erythroid-specific protein that binds specifically to free alpha-(haemo)globin, might account for some of the clinical variability in beta-thalassaemia. To assess the variation of AHSP expression, mRNA levels in circulating reticulocytes of 103 healthy individuals were measured by quantitative reverse transcription-polymerase chain reaction. AHSP expression varied up to threefold, and did not correlate with age or sex. A systematic survey of the AHSP locus identified eight sequence variants, of which six were common. Four common variants, including the longer homopolymer (T18) in the putative promoter, are strongly associated with AHSP expression. Reporter assays in K562 cells showed that the activity of the shorter (T15) reporter was relatively lower than that of the T18 reporter. In a study of nine anaemic patients who were heterozygous for beta-thalassaemia and also heterozygous for the triplicated alpha-globin gene (alpha alpha alpha/alpha alpha), frequency of the shorter homopolymer was higher than expected. AHSP expression is variable, with cis control accounting for some of its variance. In some families, the subtle altered levels in AHSP related to the AHSP genotype appears to be a relevant contributory factor in the haematological phenotype.
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Affiliation(s)
- Mei I Lai
- Molecular Haematology, Division of Gene and Cell Based Therapy, King's College London School of Medicine, London, UK
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