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Lee JY, Huh HD, Lee DK, Park SY, Shin JE, Gee HY, Park HW. Reprogramming anchorage dependency to develop cell lines for recombinant protein expression. Biotechnol J 2024; 19:e2400104. [PMID: 38700448 DOI: 10.1002/biot.202400104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/25/2024] [Accepted: 04/01/2024] [Indexed: 05/05/2024]
Abstract
As the biopharmaceutical industry continues to mature in its cost-effectiveness and productivity, many companies have begun employing larger-scale biomanufacturing and bioprocessing protocols. While many of these protocols require cells with anchorage-independent growth, it remains challenging to induce the necessary suspension adaptations in many different cell types. In addition, although transfection efficiency is an important consideration for all cells, especially for therapeutic protein production, cells in suspension are generally more difficult to transfect than adherent cells. Thus, much of the biomanufacturing industry is focused on the development of new human cell lines with properties that can support more efficient biopharmaceutical production. With this in mind, we identified a set of "Adherent-to-Suspension Transition" (AST) factors, IKZF1, BTG2 and KLF1, the expression of which induces adherent cells to acquire anchorage-independent growth. Working from the HEK293A cell line, we established 293-AST cells and 293-AST-TetR cells for inducible and reversible reprogramming of anchorage dependency. Surprisingly, we found that the AST-TetR system induces the necessary suspension adaptations with an accompanying increase in transfection efficiency and protein expression rate. Our AST-TetR system therefore represents a novel technological platform for the development of cell lines used for generating therapeutic proteins.
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Affiliation(s)
- Ju Young Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Hyunbin D Huh
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Dong Ki Lee
- Department of Pharmacology, Graduate School of Medical Science, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - So Yeon Park
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Ji Eun Shin
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Heon Yung Gee
- Department of Pharmacology, Graduate School of Medical Science, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hyun Woo Park
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
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2
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Novel insights into plasma biomarker candidates in patients with chronic mountain sickness based on proteomics. Biosci Rep 2021; 41:227462. [PMID: 33393624 PMCID: PMC7816071 DOI: 10.1042/bsr20202219] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/22/2020] [Accepted: 12/24/2020] [Indexed: 12/16/2022] Open
Abstract
Chronic mountain sickness (CMS) is a progressive incapacitating syndrome induced by lifelong exposure to hypoxia. In the present study, proteomic analysis was used to identify the differentially expressed proteins (DEPs) and then evaluate the potential plasma biomarkers between CMS and non-CMS groups. A total of 145 DEPs were detected in CMS Han Chinese people who live in the plateau (CMS-HPu), among which 89 were significantly up-regulated and 56 were significantly down-regulated. GO enrichment analysis showed that various biological processes were enriched, including the hydrogen peroxide metabolic/catabolic process, reactive oxygen species (ROS) metabolic, and acute inflammatory response. Protein–protein interaction analysis showed that antioxidant activity, the hydrogen peroxide catabolic process and peroxidase activity were primarily mapped in interaction proteins. Nine modules showed significantly clustering based on WGCNA analysis, with two being the most significant, and GO analysis showed that proteins of both modules were primarily enriched in oxidative stress-related biological processes. Four DEPs increased in CMS patients were evaluated as the candidate biomarkers, and three showed significant AUC: hemoglobin β chain (HB-β), thioredoxin-1 (TRX1), and phosphoglycerate kinase 1 (PGK1). The present study provides insights into the pathogenesis of CMS and further evaluates the potentially biomarkers for its prevention and treatment of it.
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3
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Saha D, Koli S, Reddy KVR. Transcriptional regulation of Hb-
α and Hb-
β through nuclear factor E2-related factor-2 (Nrf2
) activation in human vaginal cells: A novel mechanism of cellular adaptability to oxidative stress. Am J Reprod Immunol 2017; 77. [DOI: 10.1111/aji.12645] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 01/13/2017] [Indexed: 12/14/2022] Open
Affiliation(s)
- Debarchana Saha
- Division of Molecular Immunology and Microbiology (MIM); National Institute for Research in Reproductive Health (NIRRH); Mumbai India
| | - Swanand Koli
- Division of Molecular Immunology and Microbiology (MIM); National Institute for Research in Reproductive Health (NIRRH); Mumbai India
| | - Kudumula Venkata Rami Reddy
- Division of Molecular Immunology and Microbiology (MIM); National Institute for Research in Reproductive Health (NIRRH); Mumbai India
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4
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Zheng Y, Miyamoto DT, Wittner BS, Sullivan JP, Aceto N, Jordan NV, Yu M, Karabacak NM, Comaills V, Morris R, Desai R, Desai N, Emmons E, Milner JD, Lee RJ, Wu CL, Sequist LV, Haas W, Ting DT, Toner M, Ramaswamy S, Maheswaran S, Haber DA. Expression of β-globin by cancer cells promotes cell survival during blood-borne dissemination. Nat Commun 2017; 8:14344. [PMID: 28181495 PMCID: PMC5321792 DOI: 10.1038/ncomms14344] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 12/20/2016] [Indexed: 12/14/2022] Open
Abstract
Metastasis-competent circulating tumour cells (CTCs) experience oxidative stress in the bloodstream, but their survival mechanisms are not well defined. Here, comparing single-cell RNA-Seq profiles of CTCs from breast, prostate and lung cancers, we observe consistent induction of β-globin (HBB), but not its partner α-globin (HBA). The tumour-specific origin of HBB is confirmed by sequence polymorphisms within human xenograft-derived CTCs in mouse models. Increased intracellular reactive oxygen species (ROS) in cultured breast CTCs triggers HBB induction, mediated through the transcriptional regulator KLF4. Depletion of HBB in CTC-derived cultures has minimal effects on primary tumour growth, but it greatly increases apoptosis following ROS exposure, and dramatically reduces CTC-derived lung metastases. These effects are reversed by the anti-oxidant N-Acetyl Cysteine. Conversely, overexpression of HBB is sufficient to suppress intracellular ROS within CTCs. Altogether, these observations suggest that β-globin is selectively deregulated in cancer cells, mediating a cytoprotective effect during blood-borne metastasis. Circulating tumour cells contribute to metastatic spread. Here the authors find that beta-chain of haemoglobin is overexpressed in those cells and protects them from oxidative stress, prolonging their survival in circulation and thereby increasing the likelihood of metastasis formation.
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Affiliation(s)
- Yu Zheng
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - David T Miyamoto
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Ben S Wittner
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - James P Sullivan
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Nicola Aceto
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Nicole Vincent Jordan
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Min Yu
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Nezihi Murat Karabacak
- Center for Bioengineering in Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Valentine Comaills
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Robert Morris
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Rushil Desai
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Niyati Desai
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Erin Emmons
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - John D Milner
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Richard J Lee
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Chin-Lee Wu
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Lecia V Sequist
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Wilhelm Haas
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - David T Ting
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Mehmet Toner
- Center for Bioengineering in Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Sridhar Ramaswamy
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Shyamala Maheswaran
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Daniel A Haber
- Massachusetts General Cancer Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA.,Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
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5
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Saha D, Koli S, Patgaonkar M, Reddy KVR. Expression of hemoglobin-α and β subunits in human vaginal epithelial cells and their functional significance. PLoS One 2017; 12:e0171084. [PMID: 28178273 PMCID: PMC5298339 DOI: 10.1371/journal.pone.0171084] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 01/16/2017] [Indexed: 11/18/2022] Open
Abstract
Hemoglobin (Hb) is a major protein involved in transport of oxygen (O2). It consists of Hb-α and Hb-β subunits, which are normally expressed by cells of erythroid lineage. However, till recently, it was not known whether non-erythroid cells like vaginal cells synthesize Hb and whether it has any functional significance. Therefore, we designed the following objectives: (1) to establish in-vitro culture system of human primary vaginal epithelial cells (hPVECs), (2) to determine whether Hb-α and Hb-β proteins are truly synthesized by hPVECs, (3) to evaluate the effect of LPS (lipopolysaccharide) on the expression of Hb-α and Hb-β proteins (4) to decipher the significance of the Hb-α and Hb-β expression in hPVECs and (5) to determine the molecular mechanism regulating the expression of Hb-α in hPVECs. To accomplish these studies, we applied a battery of assays such as RT-PCR, qRT-PCR, Flow cytometry, western blot, and immunofluorescence, Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP). The results revealed the expression of Hb-α and Hb-β at both mRNA and protein level in hPVECs. The expression was significantly upregulated following LPS treatment (10μg/ml for 6 hrs) and these results are comparable with the expression induced by LPS in human vaginal epithelial cell line (VK2/E6E7). These cells constitutively produced low levels of pro-inflammatory (IL-6) and anti-inflammatory (IL-10) cytokines. Also, the response of phosphorylated (p65)-NF-κB to LPS was upregulated with increased expression of IL-6, Toll-like receptor-4 (TLR4) and human beta defensin-1 (hBD-1) in hPVECs and VK2/E6E7 cells. However, Bay 11-7082 treatment (5μM for 24 hrs) could neutralize the effect of LPS-induced p65-NF-κB activity and represses the production`of Hb-α and Hb-β. The results of EMSA revealed the presence of putative binding sites of NF-κB in the human Hb-α promoter region (nt-115 to -106). ChIP analysis confirmed the binding of NF-κB to Hb-α promoter. In conclusion, the present findings revealed for the first time that hPVECs synthesized Hb-α and Hb-β and the expression is comparable with the expression of VK2/E6E7 cells. The identification of NF-κB regulatory sequences in Hb-α promoter, whose activation is associated with immune response of hPVECs, indicating Hb-α and Hb-β may act as an endogenous antimicrobial defense protein against vaginal inflammation/infections.
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Affiliation(s)
- Debarchana Saha
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), Parel, Mumbai, India
| | - Swanand Koli
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), Parel, Mumbai, India
| | - Mandar Patgaonkar
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), Parel, Mumbai, India
| | - Kudumula Venkata Rami Reddy
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), Parel, Mumbai, India
- * E-mail:
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6
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Saha D, Patgaonkar M, Shroff A, Ayyar K, Bashir T, Reddy KVR. Hemoglobin expression in nonerythroid cells: novel or ubiquitous? Int J Inflam 2014; 2014:803237. [PMID: 25431740 PMCID: PMC4241286 DOI: 10.1155/2014/803237] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 10/10/2014] [Accepted: 10/12/2014] [Indexed: 12/24/2022] Open
Abstract
Hemoglobin (Hb) is a major protein involved in transport of oxygen (O2). Red blood cells (RBCs) contain maximum amount of Hb and because of their unique structure and plasticity they transport O2 to various tissues of the body at an optimal concentration. Recently, it has been reported that, apart from RBCs, Hb is also expressed by nonerythroid cells such as epithelial cells of different origin. The cells expressing Hb are from the tissues where maintenance of O2 homeostasis is of paramount importance. Hb expression has been observed in the epithelial cells from human tissues including lungs, neurons, retina, and endometrium. Our group has recently demonstrated that Hb is expressed by the cervicovaginal epithelial cells. We further showed that, apart from maintaining O2 homeostasis, Hb and the peptides derived from it play an indispensable role in the protection of vaginal epithelium by exhibiting antimicrobial activity. In this review, we discuss the significance of Hb expression in vaginal epithelial cells and its role in the recognition of pathogens thereby reducing the risk and/or severity of inflammation and/or infections and the possible mechanism by which Hb exhibits antimicrobial and antioxidative functions.
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Affiliation(s)
- Debarchana Saha
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), J.M. Street, Parel, Mumbai 400012, India
| | - Mandar Patgaonkar
- Department of Biological Sciences, Tata Institute of Fundamental Research (TIFR), Mumbai 400005, India
| | - Ankit Shroff
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), J.M. Street, Parel, Mumbai 400012, India
| | - Kanchana Ayyar
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), J.M. Street, Parel, Mumbai 400012, India
| | - Tahir Bashir
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), J.M. Street, Parel, Mumbai 400012, India
| | - K. V. R. Reddy
- Division of Molecular Immunology and Microbiology (MIM), National Institute for Research in Reproductive Health (NIRRH), J.M. Street, Parel, Mumbai 400012, India
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7
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Cellular Reprogramming toward the Erythroid Lineage. Int J Cell Biol 2011; 2011:501464. [PMID: 21811503 PMCID: PMC3146985 DOI: 10.1155/2011/501464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 05/08/2011] [Indexed: 01/09/2023] Open
Abstract
Haemoglobinopathies such as thalassaemia and sickle cell disease present a major health burden. Currently, the main forms of treatment for these diseases are packed red blood cell transfusions and the administration of drugs which act to nonspecifically reactivate the production of foetal haemoglobin. These treatments are ongoing throughout the life of the patient and are associated with a number of risks, such as limitations in available blood for transfusion, infections, iron overload, immune rejection, and side effects associated with the drug treatments. The field of cellular reprogramming has advanced significantly in the last few years and has recently culminated in the successful production of erythrocytes in culture. This paper will discuss cellular reprogramming and its potential relevance to the treatment of haemoglobinopathies.
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8
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da Cunha AF, Brugnerotto AF, Duarte AS, Lanaro C, Costa GGL, Saad STO, Costa FF. Global gene expression reveals a set of new genes involved in the modification of cells during erythroid differentiation. Cell Prolif 2010; 43:297-309. [PMID: 20546246 DOI: 10.1111/j.1365-2184.2010.00679.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
OBJECTIVES Erythroid differentiation is a dynamic process in which a pluripotent stem cell undergoes a series of developmental changes that commit it to a specific lineage. These alterations involve changes in gene expression profiles. In this study, gene expression profiles during differentiation of human erythroid cells of a normal blood donor were evaluated using SAGE. MATERIALS AND METHODS Global gene expression was evaluated in cells collected immediately before addition of erythropoietin (0 h) and 192 and 336 h after addition of this hormone. Real-time PCR was used to evaluate activation of differentially expressed genes. RESULTS The data indicate that global aspects of the transcriptome were similar during differentiation of the majority of the genes and that a relatively small set of genes is probably involved in modification of erythroid cells during differentiation. We have identified 93 differentially expressed genes during erythroid development, and expression of some of these was confirmed by qPCR. Various genes including EYA3, ERH, HES6, TIMELESS and TRIB3 were found to be homologous to those of Drosophila melanogaster and here are described for the first time during erythroid development. An important and unique carboxypeptidase inhibitor described in mammalians, LXN, was also identified. CONCLUSIONS The results of this study amplify previously published data and may contribute to comprehension of erythroid differentiation and identification of new target genes involved in some erythroid concerning diseases.
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Affiliation(s)
- A F da Cunha
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil.
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9
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Cluster specific regulation pattern of upstream regulatory elements in human alpha- and beta-globin gene clusters. Exp Cell Res 2007; 314:115-22. [PMID: 17996867 DOI: 10.1016/j.yexcr.2007.08.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Revised: 08/15/2007] [Accepted: 08/18/2007] [Indexed: 11/22/2022]
Abstract
Located in different chromatin contexts and with different developmental switching mode, human alpha- and beta-globin gene clusters are co-regulated temporally and quantitatively to keep balanced expression. Here, by exchanging their key upstream regulatory elements (UREs) in cluster level, and investigating the expression level of exogenous globin genes in the bacterial artificial chromosome (BAC) mediated transgenic mice, we explored the similarities and differences in the regulatory effects between alpha-upstream regulatory element (alpha-URE) and beta-locus control region (beta-LCR). The results showed that, after exchange, the developmental switching modes of human alpha- and beta-like globin genes had changed, with lost expression of epsilon- and alpha1-genes. Their expression levels also decreased. Our study suggests that the regulation of alpha-URE and beta-LCR on the expression level and developmental switching mode of downstream globin genes is cluster specific.
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10
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Parsons SDC, Penzhorn BL, Reyers F, Steyl JCA, Becker PJ. Erythrocyte Morphology and Haemoglobin Types of Neonatal Roan Antelopes (Hippotragus equinus) with Hypochromic Poikilocytic Anaemia. J Comp Pathol 2006; 134:152-60. [PMID: 16542675 DOI: 10.1016/j.jcpa.2005.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Accepted: 09/28/2005] [Indexed: 10/24/2022]
Abstract
Neonatal, poikilocytic anaemia in some members of the Hippotragini has previously been documented but not fully investigated. This study was undertaken to describe the erythrocyte morphology of roan antelopes (Hippotragus equinus) during the first 4 weeks after birth and to identify aspects of haemoglobin (Hb) production that might be implicated in this syndrome. Twenty-nine roan antelope calves were sampled on, or close to, 1, 7, 14 and 28 days after birth. Erythrocyte morphology was characterized, and microhaematocrit values and Hb parameters determined, for each sampling occasion. Findings indicated a significant change in erythrocyte morphology during the neonatal period and two haemoglobin types, fetal and adult, were identified. The perinatal onset of adult Hb synthesis was delayed relative to the termination of fetal Hb production, resulting in the observed anaemia. Haemoglobin concentration and erythrocyte morphology were significantly correlated. These findings suggest an intimate relationship between Hb synthesis and the observed poikilocytosis. An imbalance in the synthesis of the alpha- and beta-globin chains of Hb (a thalassaemia) may prove to be the underlying pathophysiology of this syndrome.
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MESH Headings
- Anemia, Hemolytic, Congenital/blood
- Anemia, Hemolytic, Congenital/pathology
- Anemia, Hemolytic, Congenital/veterinary
- Anemia, Hypochromic/blood
- Anemia, Hypochromic/pathology
- Anemia, Hypochromic/veterinary
- Animal Diseases/pathology
- Animals
- Animals, Newborn
- Antelopes/blood
- Chromatography, High Pressure Liquid/veterinary
- Electrophoresis/veterinary
- Erythrocyte Indices/veterinary
- Erythrocytes, Abnormal/pathology
- Fetal Hemoglobin/analysis
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Affiliation(s)
- S D C Parsons
- Veterinary Wildlife Unit, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, 0110 South Africa
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11
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Kang HC, Chae JH, Lee YH, Park MA, Shin JH, Kim SH, Ye SK, Cho YS, Fiering S, Kim CG. Erythroid cell-specific alpha-globin gene regulation by the CP2 transcription factor family. Mol Cell Biol 2005; 25:6005-20. [PMID: 15988015 PMCID: PMC1168829 DOI: 10.1128/mcb.25.14.6005-6020.2005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously demonstrated that ubiquitously expressed CP2c exerts potent erythroid-specific transactivation of alpha-globin through an unknown mechanism. This mechanism is reported here to involve specific CP2 splice variants and protein inhibitor of activated STAT1 (PIAS1). We identify a novel murine splice isoform of CP2, CP2b, which is identical to CP2a except that it has an additional 36 amino acids encoded by an extra exon. CP2b has an erythroid cell-specific transcriptional activation domain, which requires the extra exon and can form heteromeric complexes with other CP2 isoforms, but lacks the DNA binding activity found in CP2a and CP2c. Transcriptional activation of alpha-globin occurred following dimerization between CP2b and CP2c in erythroid K562 and MEL cells, but this dimerization did not activate the alpha-globin promoter in nonerythroid 293T cells, indicating that an additional erythroid factor is missing in 293T cells. PIAS1 was confirmed as a CP2 binding protein by the yeast two-hybrid screen, and expression of CP2b, CP2c, and PIAS1 in 293T cell induced alpha-globin promoter activation. These results show that ubiquitously expressed CP2b exerts potent erythroid cell-specific alpha-globin gene expression by complexing with CP2c and PIAS1.
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Affiliation(s)
- Ho Chul Kang
- Department of Life Science and Research Institute for Natural Sciences, College of Natural Sciences, Hanyang University, Haengdang 17, Sungdong-gu, Seoul 133-791, South Korea
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12
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Xue L, Chen X, Chang Y, Bieker JJ. Regulatory elements of the EKLF gene that direct erythroid cell-specific expression during mammalian development. Blood 2004; 103:4078-83. [PMID: 14764531 DOI: 10.1182/blood-2003-09-3231] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
AbstractErythroid Krüppel-like factor (EKLF) plays an essential role in enabling β-globin expression during erythroid ontogeny. It is first expressed in the extraembryonic mesoderm of the yolk sac within the morphologically unique cells that give rise to the blood islands, and then later within the hepatic primordia. The BMP4/Smad pathway plays a critical role in the induction of EKLF, and transient transfection analyses demonstrate that sequences located within less than 1 kb of its transcription initiation site are sufficient for high-level erythroid-specific transcription. We have used transgenic analyses to verify that 950 bp located adjacent to the EKLF start site of transcription is sufficient to generate lacZ expression within the blood islands as well as the fetal liver during embryonic development. Of particular importance are 3 regions, 2 of which overlap endogenous erythroid-specific DNase hypersensitive sites, and 1 of which includes the proximal promoter region. The onset of transgene expression mimics that of endogenous EKLF as it begins by day 7.5 (d7.5) to d8.0. In addition, it exhibits a strict hematopoietic specificity, localized only to these cells and not to the adjacent vasculature at all stages examined. Finally, expression is heterocellular, implying that although these elements are sufficient for tissue-specific expression, they do not shield against the position effects of adjacent chromatin. These analyses demonstrate that a surprisingly small DNA segment contains all the information needed to target a linked gene to the hematopoietic compartment at both early and later stages of development, and may be a useful cassette for this purpose.
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Affiliation(s)
- Li Xue
- Mount Sinai School of Medicine, Brookdale Department of Molecular, Cell, and Developmental Biology, Box 1020, One Gustave L. Levy Pl, New York, NY 10029, USA
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13
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Scicchitano MS, McFarland DC, Tierney LA, Narayanan PK, Schwartz LW. In vitro expansion of human cord blood CD36+ erythroid progenitors: temporal changes in gene and protein expression. Exp Hematol 2003; 31:760-9. [PMID: 12962721 DOI: 10.1016/s0301-472x(03)00185-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Erythropoiesis involves proliferation and differentiation of committed erythroid progenitors to mature red blood cells. The objective of this study was to characterize growth characteristics of human CD36+ erythroid progenitors and to profile temporal expression of lineage-specific transcription factors, structural proteins, and growth factor receptors involved in erythropoiesis. MATERIALS AND METHODS Erythropoietin-induced differentiation of human cord blood CD36+ erythroid progenitors was profiled for GATA-1, GATA-2, NFE2, EKLF, SCL, PU.1, Id1, Evi-1, c-myb, Hox2.2, c-kit, EpoR, glycophorin A (GPA), CD71, beta- and gamma-globin, and protein 4.2 gene and/or protein expression and DNA content analysis on days 4, 7, and 15 of culture. RESULTS Real-time RT-PCR analysis revealed upregulation of GATA-1, Id1, glycophorin A, and protein 4.2 mRNA expression on day 7 when compared to day 4 and decreased expression on day 15. EKLF, GATA-2, Hox2.2, c-myb, Evi-1, c-kit, and PU.1 mRNA expression decreased on days 7 and 15. NFE2, CD71, SCL, and EPO-R mRNA expression remained similar on days 4 and 7 but decreased on day 15. Expression of globin genes beta- and gamma-globin increased on both day 7 and day 15 compared to day 4. Values from flow cytometric quantitation of glycophorin A, transferrin receptor (CD71), and hemoglobin A proteins correlated with gene expression results. DNA analysis demonstrated that most cells lacked DNA content by day 15, a finding consistent with enucleation and terminal erythroid differentiation. CONCLUSION These data indicate that in vitro liquid cultures of committed CD36+ erythroid progenitor cells retain, in part, many features of erythropoiesis at the cellular and molecular level and may provide a useful model for assessment of disease-related or drug-induced erythropoietic abnormalities.
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Routledge SJE, Proudfoot NJ. Definition of transcriptional promoters in the human beta globin locus control region. J Mol Biol 2002; 323:601-11. [PMID: 12419253 DOI: 10.1016/s0022-2836(02)01011-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Our previous studies on the human beta globin gene cluster revealed the presence of intergenic transcripts throughout the locus, and demonstrated that transcription of the locus control region (LCR) initiates within an ERV9 endogenous retroviral long-terminal repeat (LTR) upstream of DNase I hypersensitive site 5. We show, using a combination of assays, that there are additional sites of transcription initiation within the LCR at hypersensitive sites 2 and 3. We have defined sites of transcription initiation, which occurs at discrete positions in a direction towards the globin genes. In addition, we show that mutation of specific transcription factor binding sites within HS2 leads to a reduction in transcription levels from within this site. We propose that these initiation events within the LCR can account for the observed orientation dependence of LCR function, and contribute to the open chromatin configuration of the beta globin locus. In addition, transcription from within the LCR hypersensitive sites could compensate for the absence of the ERV9 LTR in many transgenic mice lines, which nevertheless regulate their globin clusters correctly.
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Affiliation(s)
- S J E Routledge
- Sir William Dunn School of Pathology, South Parks Road, University of Oxford, Oxford, UK
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15
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Adelman CA, Chattopadhyay S, Bieker JJ. The BMP/BMPR/Smad pathway directs expression of the erythroid-specific EKLF and GATA1 transcription factors during embryoid body differentiation in serum-free media. Development 2002; 129:539-49. [PMID: 11807044 DOI: 10.1242/dev.129.2.539] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Erythroid cell-specific gene regulation during terminal differentiation is controlled by transcriptional regulators, such as EKLF and GATA1, that themselves exhibit tissue-restricted expression patterns. Their early expression, already in evidence within multipotential hematopoietic cell lines, has made it difficult to determine what extracellular effectors and transduction mechanisms might be directing the onset of their own transcription during embryogenesis. To circumvent this problem, we have taken the novel approach of investigating whether the ability of embryonic stem (ES) cells to mimic early developmental patterns of cellular expression during embryoid body (EB) differentiation can address this issue. We first established conditions whereby EBs could form efficiently in the absence of serum. Surprisingly, in addition to mesoderm, these cells expressed hemangioblast and hematopoietic markers. However, they did not express the committed erythroid markers EKLF and GATA1, nor the terminally differentiated β-like globin markers. Using this system, we determined that EB differentiation in BMP4 was necessary and sufficient to recover EKLF and GATA1 expression and could be further stimulated by the inclusion of VEGF, SCF, erythropoietin and thyroid hormone. EBs were competent to respond to BMP4 only until day 4 of differentiation, which coincides with the normal onset of EKLF expression. The direct involvement of the BMP/Smad pathway in this induction process was further verified by showing that erythroid expression of a dominant negative BMP1B receptor or of the inhibitory Smad6 protein prevented induction of EKLF or GATA1 even in the presence of serum. Although Smad1, Smad5 and Smad8 are all expressed in the EBs, BMP4 induction of EKLF and GATA1 transcription is not immediate. These data implicate the BMP/Smad induction system as being a crucial pathway to direct the onset of EKLF and GATA1 expression during hematopoietic differentiation and demonstrate that EB differentiation can be manipulated to study induction of specific genes that are expressed early within a lineage.
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Affiliation(s)
- Carrie A Adelman
- Department of Biochemistry and Molecular Biology, Mount Sinai School of Medicine, New York, NY 10029, USA
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16
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Zhang W, Kadam S, Emerson BM, Bieker JJ. Site-specific acetylation by p300 or CREB binding protein regulates erythroid Krüppel-like factor transcriptional activity via its interaction with the SWI-SNF complex. Mol Cell Biol 2001; 21:2413-22. [PMID: 11259590 PMCID: PMC86874 DOI: 10.1128/mcb.21.7.2413-2422.2001] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2000] [Accepted: 01/03/2001] [Indexed: 11/20/2022] Open
Abstract
Recruitment of modifiers and remodelers to specific DNA sites within chromatin plays a critical role in controlling gene expression. The study of globin gene regulation provides a convergence point within which to address these issues in the context of tissue-specific and developmentally regulated expression. In this regard, erythroid Krüppel-like factor (EKLF) is critical. EKLF is a red cell-specific activator whose presence is crucial for establishment of the correct chromatin structure and high-level transcriptional induction of adult beta-globin. We now find, by metabolic labeling-immunoprecipitation experiments, that EKLF is acetylated in the erythroid cell. EKLF residues acetylated by CREB binding protein (CBP) in vitro map to Lys-288 in its transactivation domain and Lys-302 in its zinc finger domain. Although site-specific DNA binding by EKLF is unaffected by the acetylation status of either of these lysines, directed mutagenesis of Lys-288 (but not Lys-302) decreases the ability of EKLF to transactivate the beta-globin promoter in vivo and renders it unable to be superactivated by coexpressed p300 or CBP. In addition, the acetyltransferase function of CBP or p300 is required for superactivation of wild-type EKLF. Finally, acetylated EKLF has a higher affinity for the SWI-SNF chromatin remodeling complex and is a more potent transcriptional activator of chromatin-assembled templates in vitro. These results demonstrate that the acetylation status of EKLF is critical for its optimal activity and suggest a mechanism by which EKLF acts as an integrator of remodeling and transcriptional components to alter chromatin structure and induce adult beta-globin expression within the beta-like globin cluster.
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Affiliation(s)
- W Zhang
- Department of Biochemistry and Molecular Biology, Mount Sinai School of Medicine, New York, NY 10029, USA
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17
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Damante G, Tell G, Di Lauro R. A unique combination of transcription factors controls differentiation of thyroid cells. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2001; 66:307-56. [PMID: 11051768 DOI: 10.1016/s0079-6603(00)66033-6] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The thyroid follicular cell type is devoted to the synthesis of thyroid hormones. Several genes, whose protein products are essential for efficient hormone biosynthesis, are uniquely expressed in this cell type. A set of transcriptional regulators, unique to the thyroid follicular cell type, has been identified as responsible for thyroid specific gene expression; it comprises three transcription factors, named TTF-1, TTF-2, and Pax8, each of which is expressed also in cell types different from the thyroid follicular cells. However, the combination of these factors is unique to the thyroid hormone producing cells, strongly suggesting that they play an important role in differentiation of these cells. An overview of the molecular and biological features of these transcription factors is presented here. Data demonstrating that all three play also an important role in early thyroid development, at stages preceding expression of the differentiated phenotype, are also reviewed. The wide temporal expression, from the beginning of thyroid organogenesis to the adult state, is suggestive of a recycling of the thyroid-specific transcription factors, that is, the control of different sets of target genes at diverse developmental stages. The identification of molecular mechanisms leading to specific gene expression in thyroid cells renders this cell type an interesting model in which to address several aspects of cell differentiation and organogenesis.
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Affiliation(s)
- G Damante
- Dipartimento di Scienze e Tecnologie Biomediche Università di Udine
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18
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Zermati Y, Varet B, Hermine O. TGF-beta1 drives and accelerates erythroid differentiation in the epo-dependent UT-7 cell line even in the absence of erythropoietin. Exp Hematol 2000; 28:256-66. [PMID: 10720690 DOI: 10.1016/s0301-472x(99)00155-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE TGF-beta1 is a powerful inhibitor of erythropoiesis. However, its mechanisms of action are not fully elucidated yet at the cellular level. In this work we have studied the effects of TGF-beta on UT-7 cell survival, proliferation and differentiation. MATERIALS AND METHODS UT-7 cell line is strictly dependent on growth factors for cell survival, growth, and differentiation. Epo (2 U/mL) induces erythroid differentiation as assessed by up regulation of glycophorin A and the presence of 5%-10% benzidine positive cells (BPC). In contrast, even in the presence of Epo (2 U/mL), GM-CSF (1 ng/mL) inhibits erythroid differentiation. RESULTS When UT-7 cells were switched from GM-CSF to Epo, TGF-beta1 (2 ng/mL) induced a rapid (3 days [Epo+TGF-beta1] vs 8 days [Epo]) and marked erythroid differentiation (80% [Epo+TGF-beta1] vs 10% [Epo] BPC) including Hemoglobin A synthesis (HbA/HbF ratio of 1 [Epo] vs 4 [Epo+TGF-beta1]). In the presence of GM-CSF, although to a lesser extent, TGF-beta1 induced erythroid differentiation (40% BPC). This effect was not a consequence of TGF-beta1-induced apoptosis because, in the presence of Epo or GM-CSF, apoptosis occurred only at day 8 or 10, respectively. Moreover, although SCF inhibited apoptotic effect of TGF-beta1, SCF+TGF-beta1+Epo was the best combination to give rise to the highest number of hemoglobinized cells. We further demonstrated that induction of erythroid differentiation by TGF-beta1 was not due to an autocrine loop involving Epo/Epo-R or to a prolongation of the G1 phase of the cell cycle. CONCLUSION Taken together, these data suggest that TGF-beta1 is an inducer of erythroid differentiation, even stronger than Epo at the cellular level.
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Affiliation(s)
- Y Zermati
- CNRS UMR 8603 and IFR Necker, Université René Descartes (Paris V), Paris, France
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19
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Abstract
Pc-G and trx-G genes are responsible for maintenance of transcriptional regulation and provide a cellular memory mechanism throughout development. Studies in fly, yeast, mouse, and human have implicated modulation of higher-order chromatin structure as an important component in this process. Specifically, connections between SWI/SNF complexes and trx-G genes have provided a mechanistic link between chromatin remodeling and transcriptional regulation. Here we discuss recent genetic and biochemical data that has shed light on the molecular mechanisms and pathways associated with Pc-G and trx-G function in developmental processes such as cell cycle control and hematopoiesis. genesis 26:189-197, 2000.
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Affiliation(s)
- T C Gebuhr
- Department of Genetics, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
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20
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Ji XJ, Liu DP, Xu DD, Li L, Wang J, Liang CC. Both locus control region and proximal regulatory elements direct the developmental regulation of ?-globin gene cluster. J Cell Biochem 2000. [DOI: 10.1002/(sici)1097-4644(20000301)76:3<376::aid-jcb5>3.0.co;2-d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Sadlon TJ, Dell'Oso T, Surinya KH, May BK. Regulation of erythroid 5-aminolevulinate synthase expression during erythropoiesis. Int J Biochem Cell Biol 1999; 31:1153-67. [PMID: 10582344 DOI: 10.1016/s1357-2725(99)00073-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Erythroid tissue is the major site of heme production in the body. The synthesis of heme and globin chains is coordinated at both the transcriptional and post-transcriptional levels to ensure that virtually no free heme or globin protein accumulates. The key rate-controlling enzyme of the heme biosynthetic pathway is 5-aminolevulinate synthase (ALAS) and an erythroid-specific isoform (ALAS2) is up-regulated during erythropoiesis. Differentiation of embryonic stem cells with a disrupted ALAS2 gene has established that expression of this gene is critical for erythropoiesis and cannot be compensated by expression of the ubiquitous isoform of the enzyme (ALAS1). Interestingly, heme appears to be important for expression of globin and other late erythroid genes and for erythroid cell differentiation although the mechanism of this effect is not clear. Transcriptional control elements that regulate the human gene for ALAS2 have been identified both in the promoter and in intronic enhancer regions. Subsequent translation of the ALAS2 mRNA is dependent on an adequate iron supply. The mechanism by which transcription of the gene for ALAS2 is increased by erythropoietin late in erythropoiesis remains an interesting issue. Erythropoietin action may result in altered levels of critical erythroid transcription factors or modulate the phosphorylation/acetylation status of these factors. Defects in the coding region of the gene for ALAS2 underlie the disease state X-linked sideroblastic anemia. In this review, we focus on the regulation and function of erythroid-specific 5-aminolevulinate synthase during erythropoiesis and its role in the X-linked sideroblastic anemia.
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Affiliation(s)
- T J Sadlon
- Department of Biochemistry, University of Adelaide, SA, Australia
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22
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Yuan XJ, McCarthy BD, Salgar SK, Kunz HW, Gill TJ. Biological effects of genes in the Grc and EC region of the rat major histocompatibility complex. Am J Reprod Immunol 1999; 42:64-9. [PMID: 10429769 DOI: 10.1111/j.1600-0897.1999.tb00467.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
PROBLEM To study the mechanism of action of major histocompatibility complex (MHC)-linked genes affecting reproduction, growth, and susceptibility to chemical carcinogens. METHOD OF STUDY Tumors derived from rat embryonic fibroblasts were transfected with cosmids from the Grc and its linked regions, the unrelated A region, and a nonMHC region, or with genes from the Grc, Grc-linked, and nonMHC regions, to determine whether they could suppress tumor growth as determined by in vitro (soft agar) and in vivo assays. RESULTS Tumor fibroblasts transfected with cosmids from the Grc or from the EC region decreased tumor growth in both the in vitro and in vivo assays. Transfection with individual genes from the Grc had no effect on tumor growth in either assay. CONCLUSIONS The effects of the Grc on reproduction, growth, and tumorigenesis are mediated by extended genetic effects, i.e., by the conformation of the DNA in this region. Similar effects were seen following transfection with cosmids from the Grc-linked EC region, and this finding strengthens the hypothesis that the conformation of the DNA in this general region is critical for its function. A similar effect has been described for the locus control region (LCR) in the beta-globin gene family in the human.
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Affiliation(s)
- X J Yuan
- Department of Pathology, University of Pittsburgh, School of Medicine, PA 15261, USA
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23
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Abstract
The common perception that hemoglobin is involved solely in the transport of oxygen and carbon dioxide has been challenged by recent studies with nitric oxide (NO). These studies have shown that the primordial bacterial flavohemoglobin functions to consume NO enzymatically (to protect from nitrosative stress), whereas mammalian hemoglobin functions to deliver NO (thus maximizing oxygen delivery in the respiratory cycle). Here we report that murine macrophages stimulated to produce NO with lipopolysaccharide and interferon-gamma express the betaminor hemoglobin subunit. Consumption of NO, however, was not increased by cytokines or by hemoglobin expression. These data suggest alternative functions for globins in mammalian cells, and they challenge the prevailing view that the expression of alpha- and beta-globin genes is always balanced and coordinated.
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Affiliation(s)
- L Liu
- Howard Hughes Medical Institute, Pulmonary and Cardiology Divisions, Duke University Medical Center, Durham, NC 27710, USA
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24
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O'Neill D, Yang J, Erdjument-Bromage H, Bornschlegel K, Tempst P, Bank A. Tissue-specific and developmental stage-specific DNA binding by a mammalian SWI/SNF complex associated with human fetal-to-adult globin gene switching. Proc Natl Acad Sci U S A 1999; 96:349-54. [PMID: 9892636 PMCID: PMC15139 DOI: 10.1073/pnas.96.2.349] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SWI/SNF complexes in yeast and higher eukaryotes are thought to facilitate gene activation and transcription factor binding by disrupting repressive chromatin structures. Little is known, however, about how these complexes target specific genes for activation. We now have purified a specialized SWI/SNF-related complex (PYR complex) from murine erythroleukemia (MEL) cell nuclear extract that binds pyrimidine-rich elements at the human and murine beta-globin loci. PYR complex DNA-binding activity is restricted to definitive hematopoietic cells and is both DNA sequence- and length-dependent. Mass spectrometric identification of purified peptides and antibody supershift assays indicate that PYR complex contains at least four known mammalian SWI/SNF subunits: BAF57, INI1, BAF60a, and BAF170. PYR complex broadly footprints a 250-bp pyrimidine-rich element between the human fetal and adult beta-globin genes. A short intergenic deletion that removes this element from a human globin locus cosmid construct results in delayed human fetal-to-adult globin gene switching in transgenic mice. Taken together, the data suggest that PYR complex may act through this intergenic element to facilitate human fetal-to-adult globin gene switching, presumably by opening the locus in the region of the adult genes to permit the binding of beta-globin transcriptional activators.
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Affiliation(s)
- D O'Neill
- Department of Pathology, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, NY 10032, USA
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25
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Gill TJ. Mechanisms of action of major-histocompatibility-complex-linked genes affecting reproduction. Am J Reprod Immunol 1999; 41:23-33. [PMID: 10097784 DOI: 10.1111/j.1600-0897.1999.tb00072.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
PROBLEM To provide insight into the mechanisms of action of the major-histocompatibility-complex (MHC)-linked genes affecting reproduction. METHOD OF STUDY The data were obtained using a variety of cellular and molecular techniques in experimental animals and from population genetic studies in humans. RESULTS In the mouse, the preimplantation embryonic development (Ped) locus, whose functional gene is Q9, regulates fast and slow cleavage of the early embryo. There is also evidence for a growth and reproduction complex (Grc)-like region from serologic, molecular, and cytogenetic studies. In the human, the human leukocyte antigen (HLA)-G gene has been associated with an increased rate of embryonic cleavage in those embryos that express the HLA-G antigen. Sharing of HLA antigens in couples has been associated with recurrent spontaneous abortions, gestational trophoblastic tumors, and unexplained infertility. Detailed mapping studies showed that the genes responsible are not the HLA genes themselves, but genes closely linked to the HLA-DR-DQ-B genes. The HLA region genes can interact epistatically with the C3 allele of transferrin to increase the incidence of fetal loss. In the rat, the Grc region, which is closely linked to the MHC, has been associated with embryonic loss, growth defects, and susceptibility to chemical carcinogens. The Grc can interact epistatically with the tail anomaly lethal (Tal) gene or the hood restriction (Hre) gene to enhance these effects. CONCLUSIONS There are two basic mechanisms for the effects of MHC-linked genes on reproduction and development: individual gene effects (Ped [Q9], HLA-G) and extended genetic effects (MHC-linked genes in the rat [Grc] and in the human). The nature of these genetic effects, particularly the MHC-linked effects, can also provide some insight into the different theories of human origins: These effects are most consistent with the monogenic theory.
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Affiliation(s)
- T J Gill
- Department of Pathology, University of Pittsburgh, School of Medicine, PA, USA
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26
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Abstract
The most upstream hypersensitive site (HS) of the β-globin locus control region (LCR) in humans (5′ HS 5) and chickens (5′ HS 4) can act as an insulating element in some gain of function assays and may demarcate a β-globin domain. We have mapped the most upstream HSs of the mouse β-globin LCR and sequenced this region. We find that mice have a region homologous to human 5′ HS 5 that is associated with a minor HS. In addition we map a unique HS upstream of 5′ HS 5 and refer to this novel site as mouse 5′ HS 6. We have also generated mice containing a targeted deletion of the region containing 5′ HS 5 and 6. We find that after excision of the selectable marker in vivo, deletion of 5′ HS 5 and 6 has a minimal effect on transcription and does not prevent formation of the remaining LCR HSs. Taken together these findings suggest that the most upstream HSs of the mouse β-globin LCR are not necessary for maintaining the β-globin locus in an active configuration or to protect it from a surrounding repressive chromatin environment.
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27
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Description and Targeted Deletion of 5′ Hypersensitive Site 5 and 6 of the Mouse β-Globin Locus Control Region. Blood 1998. [DOI: 10.1182/blood.v92.11.4394] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The most upstream hypersensitive site (HS) of the β-globin locus control region (LCR) in humans (5′ HS 5) and chickens (5′ HS 4) can act as an insulating element in some gain of function assays and may demarcate a β-globin domain. We have mapped the most upstream HSs of the mouse β-globin LCR and sequenced this region. We find that mice have a region homologous to human 5′ HS 5 that is associated with a minor HS. In addition we map a unique HS upstream of 5′ HS 5 and refer to this novel site as mouse 5′ HS 6. We have also generated mice containing a targeted deletion of the region containing 5′ HS 5 and 6. We find that after excision of the selectable marker in vivo, deletion of 5′ HS 5 and 6 has a minimal effect on transcription and does not prevent formation of the remaining LCR HSs. Taken together these findings suggest that the most upstream HSs of the mouse β-globin LCR are not necessary for maintaining the β-globin locus in an active configuration or to protect it from a surrounding repressive chromatin environment.
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28
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Manis JP, van der Stoep N, Tian M, Ferrini R, Davidson L, Bottaro A, Alt FW. Class switching in B cells lacking 3' immunoglobulin heavy chain enhancers. J Exp Med 1998; 188:1421-31. [PMID: 9782119 PMCID: PMC2213411 DOI: 10.1084/jem.188.8.1421] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/1998] [Revised: 07/28/1998] [Indexed: 12/30/2022] Open
Abstract
The 40-kb region downstream of the most 3' immunoglobulin (Ig) heavy chain constant region gene (Calpha) contains a series of transcriptional enhancers speculated to play a role in Ig heavy chain class switch recombination (CSR). To elucidate the function of this putative CSR regulatory region, we generated mice with germline mutations in which one or the other of the two most 5' enhancers in this cluster (respectively referred to as HS3a and HS1,2) were replaced either with a pgk-neor cassette (referred to as HS3aN and HS1,2N mutations) or with a loxP sequence (referred to as HS3aDelta and HS1,2Delta, respectively). B cells homozygous for the HS3aN or HS1,2N mutations had severe defects in CSR to several isotypes. The phenotypic similarity of the two insertion mutations, both of which were cis-acting, suggested that inhibition might result from pgk-neor cassette gene insertion rather than enhancer deletion. Accordingly, CSR returned to normal in B cells homozygous for the HS3aDelta or HS1,2Delta mutations. In addition, induced expression of the specifically targeted pgk-neor genes was regulated similarly to that of germline CH genes. Our findings implicate a 3' CSR regulatory locus that appears remarkably similar in organization and function to the beta-globin gene 5' LCR and which we propose may regulate differential CSR via a promoter competition mechanism.
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Affiliation(s)
- J P Manis
- The Howard Hughes Medical Institute, Boston, Massachusetts 02115, USA
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29
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Armstrong JA, Bieker JJ, Emerson BM. A SWI/SNF-related chromatin remodeling complex, E-RC1, is required for tissue-specific transcriptional regulation by EKLF in vitro. Cell 1998; 95:93-104. [PMID: 9778250 DOI: 10.1016/s0092-8674(00)81785-7] [Citation(s) in RCA: 253] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Erythroid Krüppel-like factor (EKLF) is necessary for stage-specific expression of the human beta-globin gene. We show that EKLF requires a SWI/SNF-related chromatin remodeling complex, EKLF coactivator-remodeling complex 1 (E-RC1), to generate a DNase I hypersensitive, transcriptionally active beta-globin promoter on chromatin templates in vitro. E-RC1 contains BRG1, BAF170, BAF155, and INI1 (BAF47) homologs of yeast SWI/SNF subunits, as well as a subunit unique to higher eukaryotes, BAF57, which is critical for chromatin remodeling and transcription with EKLF. E-RC1 displays functional selectivity toward transcription factors, since it cannot activate expression of chromatin-assembled HIV-1 templates with the E box-binding protein TFE-3. Thus, a member of the SWI/SNF family acts directly in transcriptional activation and may regulate subsets of genes by selectively interacting with specific DNA-binding proteins.
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Affiliation(s)
- J A Armstrong
- Regulatory Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
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30
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Zhang W, Bieker JJ. Acetylation and modulation of erythroid Krüppel-like factor (EKLF) activity by interaction with histone acetyltransferases. Proc Natl Acad Sci U S A 1998; 95:9855-60. [PMID: 9707565 PMCID: PMC21426 DOI: 10.1073/pnas.95.17.9855] [Citation(s) in RCA: 290] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/1998] [Indexed: 11/18/2022] Open
Abstract
Erythroid Krüppel-like factor (EKLF) is a red cell-specific transcriptional activator that is crucial for consolidating the switch to high levels of adult beta-globin expression during erythroid ontogeny. EKLF is required for integrity of the chromatin structure at the beta-like globin locus, and it interacts with a positive-acting factor in vivo. We find that EKLF is an acetylated transcription factor, and that it interacts in vivo with CBP, p300, and P/CAF. However, its interactions with these histone acetyltransferases are not equivalent, as CBP and p300, but not P/CAF, utilize EKLF as a substrate for in vitro acetylation within its trans-activation region. The functional effects of these interactions are that CBP and p300, but not P/CAF, enhance EKLF's transcriptional activation of the beta-globin promoter in erythroid cells. These results establish EKLF as a tissue-specific transcription factor that undergoes post-translational acetylation and suggest a mechanism by which EKLF is able to alter chromatin structure and induce beta-globin expression within the beta-like globin cluster.
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Affiliation(s)
- W Zhang
- Brookdale Center for Molecular Biology, Mount Sinai School of Medicine, New York, NY 10029, USA
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31
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Full Activity From Human β-Globin Locus Control Region Transgenes Requires 5′HS1, Distal β-Globin Promoter, and 3′ β-Globin Sequences. Blood 1998. [DOI: 10.1182/blood.v92.2.653.414k10_653_663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The locus control region (LCR) activates high-level human β-globin transgene expression. LCR cassettes composed of 5′HS2-4 linked to the 815 bp β-globin proximal promoter do not express fully. Here, we show that LCR (5′HS2-4) β-globin transgenes that also contain either 5′HS1 or the distal promoter fail to express fully in single- and low-copy transgenic mice. In contrast, full expression is obtained in the presence of both 5′HS1 and the distal promoter. Nine factor binding sites were identified in 5′HS1, using in vitro DNaseI footprint and gel retardation assays, and these include a strong Sp1/Sp3 site, four GATA-1 sites, and two sites that encompass an ACTAAC motif. LCR (5′HS1-4) β-globin transgene constructs with the distal promoter deleted or replaced by spacer DNA show that specific distal promoter sequences are required for full expression. An LCR (5′HS1-4) transgene construct with truncated downstream β-globin gene sequences indicates that 3′ sequences also play an important role. These results show that full expression of the β-globin gene directed by the LCR requires 5′HS1, the distal β-globin promoter, and 3′ sequences, and has implications for gene therapy construct design and models of LCR activation.
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32
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Full Activity From Human β-Globin Locus Control Region Transgenes Requires 5′HS1, Distal β-Globin Promoter, and 3′ β-Globin Sequences. Blood 1998. [DOI: 10.1182/blood.v92.2.653] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The locus control region (LCR) activates high-level human β-globin transgene expression. LCR cassettes composed of 5′HS2-4 linked to the 815 bp β-globin proximal promoter do not express fully. Here, we show that LCR (5′HS2-4) β-globin transgenes that also contain either 5′HS1 or the distal promoter fail to express fully in single- and low-copy transgenic mice. In contrast, full expression is obtained in the presence of both 5′HS1 and the distal promoter. Nine factor binding sites were identified in 5′HS1, using in vitro DNaseI footprint and gel retardation assays, and these include a strong Sp1/Sp3 site, four GATA-1 sites, and two sites that encompass an ACTAAC motif. LCR (5′HS1-4) β-globin transgene constructs with the distal promoter deleted or replaced by spacer DNA show that specific distal promoter sequences are required for full expression. An LCR (5′HS1-4) transgene construct with truncated downstream β-globin gene sequences indicates that 3′ sequences also play an important role. These results show that full expression of the β-globin gene directed by the LCR requires 5′HS1, the distal β-globin promoter, and 3′ sequences, and has implications for gene therapy construct design and models of LCR activation.
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33
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Gardiner-Garden M, Ballesteros M, Gordon M, Tam PP. Histone- and protamine-DNA association: conservation of different patterns within the beta-globin domain in human sperm. Mol Cell Biol 1998; 18:3350-6. [PMID: 9584175 PMCID: PMC108916 DOI: 10.1128/mcb.18.6.3350] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Most DNA in human sperm is bound to highly basic proteins called protamines, but a small proportion is complexed with histones similar to those found in active chromatin. This raises the intriguing possibility that histones in sperm are marking sets of genes that will be preferentially activated during early development. We have examined the chromatin structure of members of the beta-globin gene family, which are expressed at different times in development, and the protamine 2 gene, which is expressed in spermatids prior to the widespread displacement of histones by transition proteins. The genes coding for epsilon and gamma globin, which are active in the embryonic yolk sac, contain regions which are histone associated in the sperm. No histone-associated regions are present at the sites tested within the beta- and delta-globin genes which are silent in the embryonic yolk sac. The trends of histone or protamine association are consistent for samples from the same person, and no significant between-subject variations in these trends are found for 13 of the 15 fragments analyzed in the two donors. The results suggest that sperm chromatin structures are generally similar in different men but that the length of the histone-associated regions can vary. The association of sperm DNA with histones or protamines sometimes changes within as little as 400 bp of DNA, suggesting that there is fine control over the retention of histones.
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Affiliation(s)
- M Gardiner-Garden
- Embryology Unit, Children's Medical Research Institute, Westmead, New South Wales 2145, Australia
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34
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Dyer MA, Hayes PJ, Baron MH. The HMG domain protein SSRP1/PREIIBF is involved in activation of the human embryonic beta-like globin gene. Mol Cell Biol 1998; 18:2617-28. [PMID: 9566881 PMCID: PMC110641 DOI: 10.1128/mcb.18.5.2617] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/1997] [Accepted: 02/09/1998] [Indexed: 02/07/2023] Open
Abstract
The human embryonic beta-like globin (epsilon-globin) gene is expressed in primitive erythroid cells of the yolk sac during the first few weeks of development. We have previously shown that developmental stage-specific expression of the epsilon-globin gene is mediated by multiple positive and negative regulatory elements upstream of the start of transcription. Of particular interest is one positive regulatory element, PRE II, that works together with other elements (PRE I and PRE V) to confer developmental stage- and/or tissue-specific expression on a minimal promoter. An approximately 85- to 90-kDa PRE II binding factor (PREIIBF) was identified in the nuclei of erythroid cells and shown to bind specifically to a novel 19-bp region within PRE II; binding of this protein to PRE II resulted in bending of the target DNA and was required for promoter activation. In this report, we present the cDNA expression cloning of PREIIBF. The cDNA encodes a previously identified member of the HMG domain family of DNA binding proteins termed SSRP1. By a number of biochemical and immunological criteria, recombinant SSRP1 appears to be identical to the PREII binding factor from erythroid nuclei. A hallmark of HMG domain proteins is their ability to bend their target DNAs; therefore, as we speculated previously, DNA bending by SSRP1/PREIIBF may contribute to the mechanism by which PRE II synergizes with other regulatory elements located upstream and downstream. In contrast with reports from other investigators, we demonstrate that SSRP1 binds DNA with clear sequence specificity. Moreover, we show that SSRP1/PREIIBF lacks a classical activation domain but that binding by this protein to PRE II is required for activation of a minimal promoter in stable erythroid cell lines. These studies provide the first evidence that SSRP1 plays a role in transcriptional regulation. SSRP1/PREIIBF may serve an architectural function by helping to coordinate the assembly of a multiprotein complex required for stage-specific regulation of the human epsilon-globin gene.
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Affiliation(s)
- M A Dyer
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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35
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Hardison R, Slightom JL, Gumucio DL, Goodman M, Stojanovic N, Miller W. Locus control regions of mammalian beta-globin gene clusters: combining phylogenetic analyses and experimental results to gain functional insights. Gene X 1997; 205:73-94. [PMID: 9461381 DOI: 10.1016/s0378-1119(97)00474-5] [Citation(s) in RCA: 175] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Locus control regions (LCRs) are cis-acting DNA segments needed for activation of an entire locus or gene cluster. They are operationally defined as DNA sequences needed to achieve a high level of gene expression regardless of the position of integration in transgenic mice or stably transfected cells. This review brings together the large amount of DNA sequence data from the beta-globin LCR with the vast amount of functional data obtained through the use of biochemical, cellular and transgenic experimental systems. Alignment of orthologous LCR sequences from five mammalian species locates numerous conserved regions, including previously identified cis-acting elements within the cores of nuclease hypersensitive sites (HSs) as well as conserved regions located between the HS cores. The distribution of these conserved sequences, combined with the effects of LCR fragments utilized in expression studies, shows that important sites are more widely distributed in the LCR than previously anticipated, especially in and around HS2 and HS3. We propose that the HS cores plus HS flanking DNAs comprise a 'unit' to which proteins bind and form an optimally functional structure. Multiple HS units (at least three: HS2, HS3 and HS4 cores plus flanking DNAs) together establish a chromatin structure that allows the proper developmental regulation of genes within the cluster.
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Affiliation(s)
- R Hardison
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park 16802, USA.
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