1
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Yang M, Tang Y, Zhu P, Lu H, Wan X, Guo Q, Xiao L, Liu C, Guo L, Liu W, Yang Y. The advances of E2A-PBX1 fusion in B-cell acute lymphoblastic Leukaemia. Ann Hematol 2023:10.1007/s00277-023-05595-7. [PMID: 38148344 DOI: 10.1007/s00277-023-05595-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/17/2023] [Indexed: 12/28/2023]
Abstract
The E2A-PBX1 gene fusion is a common translocation in B-cell acute lymphoblastic leukaemia. Patients harbouring the E2A-PBX1 fusion gene typically exhibit an intermediate prognosis. Furthermore, minimal residual disease has unsatisfactory prognostic value in E2A-PBX1 B-cell acute lymphoblastic leukaemia. However, the mechanism of E2A-PBX1 in the occurrence and progression of B-cell acute lymphoblastic leukaemia is not well understood. Here, we mainly review the roles of E2A and PBX1 in the differentiation and development of B lymphocytes, the mechanism of E2A-PBX1 gene fusion in B-cell acute lymphoblastic leukaemia, and the potential therapeutic approaches.
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Affiliation(s)
- Mengting Yang
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Yanhui Tang
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Peng Zhu
- School of Pharmacy, Wannan Medical College, Wuhu, 241000, People's Republic of China
| | - Haiquan Lu
- The Second Hospital, Centre for Reproductive Medicine, Advanced Medical Research Institute, Key Laboratory for Experimental Teratology of the Ministry of Education, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Xiaohong Wan
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Qulian Guo
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Lan Xiao
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Chunyan Liu
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Ling Guo
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China
| | - Wenjun Liu
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China.
| | - You Yang
- Department of Paediatrics (Children Haematological Oncology), Birth Defects and Childhood Haematological Oncology Laboratory, Sichuan Clinical Research Centre for Birth Defects, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
- Department of Paediatrics, Southwest Medical University, Luzhou, Sichuan, China.
- The Second Hospital, Centre for Reproductive Medicine, Advanced Medical Research Institute, Key Laboratory for Experimental Teratology of the Ministry of Education, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.
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2
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Liang JJ, Peng H, Wang JJ, Liu XH, Ma L, Ni YR, Yang HJ, Zhang YQ, Ai WB, Wu JF. Relationship between the structure and function of the transcriptional regulator E2A. ACTA ACUST UNITED AC 2021; 28:15. [PMID: 34271975 PMCID: PMC8283981 DOI: 10.1186/s40709-021-00146-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 06/30/2021] [Indexed: 11/10/2022]
Abstract
E proteins are transcriptional regulators that regulate many developmental processes in animals and lymphocytosis and leukemia in Homo sapiens. In particular, E2A, a member of the E protein family, plays a major role in the transcriptional regulatory network that promotes the differentiation and development of B and T lymphocytes. E2A-mediated transcriptional regulation usually requires the formation of E2A dimers, which then bind to coregulators. In this review, we summarize the mechanisms by which E2A participates in transcriptional regulation from a structural perspective. More specifically, the C-terminal helix-loop-helix (HLH) region of the basic HLH (bHLH) domain first dimerizes, and then the activation domains of E2A bind to different coactivators or corepressors in different cell contexts, resulting in histone acetylation or deacetylation, respectively. Then, the N-terminal basic region (b) of the bHLH domain binds to or dissociates from a specific DNA motif (E-box sequence). Last, trans-activation or trans-repression occurs. We also summarize the properties of these E2A domains and their interactions with the domains of other proteins. The feasibility of developing drugs based on these domains is discussed.
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Affiliation(s)
- Jia-Jie Liang
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Institute of Organ Fibrosis and Targeted Drug Delivery, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China
| | - Hu Peng
- Institute of Organ Fibrosis and Targeted Drug Delivery, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,The Yiling Hospital of Yichang, 32 Donghu Road, Yi Ling District, Yichang, 443100, Hubei, China
| | - Jiao-Jiao Wang
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China
| | - Xiao-Hui Liu
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China
| | - Lan Ma
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Institute of Organ Fibrosis and Targeted Drug Delivery, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China
| | - Yi-Ran Ni
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Institute of Organ Fibrosis and Targeted Drug Delivery, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China
| | - Huai-Jie Yang
- The People's Hospital of China Three Gorges University, 31 Huti Subdistrict, Xi Ling District, Yichang, 443000, Hubei, China
| | - Yan-Qiong Zhang
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Institute of Organ Fibrosis and Targeted Drug Delivery, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China.,Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China
| | - Wen-Bing Ai
- The Yiling Hospital of Yichang, 32 Donghu Road, Yi Ling District, Yichang, 443100, Hubei, China.
| | - Jiang-Feng Wu
- Medical College, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China. .,Institute of Organ Fibrosis and Targeted Drug Delivery, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China. .,Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, 8 Daxue Road, Xiling District, Yichang, 443002, China. .,The People's Hospital of China Three Gorges University, 31 Huti Subdistrict, Xi Ling District, Yichang, 443000, Hubei, China. .,The Yiling Hospital of Yichang, 32 Donghu Road, Yi Ling District, Yichang, 443100, Hubei, China.
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3
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Lochhead MR, Brown AD, Kirlin AC, Chitayat S, Munro K, Findlay JE, Baillie GS, LeBrun DP, Langelaan DN, Smith SP. Structural insights into TAZ2 domain-mediated CBP/p300 recruitment by transactivation domain 1 of the lymphopoietic transcription factor E2A. J Biol Chem 2020; 295:4303-4315. [PMID: 32098872 PMCID: PMC7105314 DOI: 10.1074/jbc.ra119.011078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 02/21/2020] [Indexed: 01/02/2023] Open
Abstract
The E-protein transcription factors guide immune cell differentiation, with E12 and E47 (hereafter called E2A) being essential for B-cell specification and maturation. E2A and the oncogenic chimera E2A-PBX1 contain three transactivation domains (ADs), with AD1 and AD2 having redundant, independent, and cooperative functions in a cell-dependent manner. AD1 and AD2 both mediate their functions by binding to the KIX domain of the histone acetyltransferase paralogues CREB-binding protein (CBP) and E1A-binding protein P300 (p300). This interaction is necessary for B-cell maturation and oncogenesis by E2A-PBX1 and occurs through conserved ΦXXΦΦ motifs (with Φ denoting a hydrophobic amino acid) in AD1 and AD2. However, disruption of this interaction via mutation of the KIX domain in CBP/p300 does not completely abrogate binding of E2A and E2A-PBX1. Here, we determined that E2A-AD1 and E2A-AD2 also interact with the TAZ2 domain of CBP/p300. Characterization of the TAZ2:E2A-AD1(1-37) complex indicated that E2A-AD1 adopts an α-helical structure and uses its ΦXXΦΦ motif to bind TAZ2. Whereas this region overlapped with the KIX recognition region, key KIX-interacting E2A-AD1 residues were exposed, suggesting that E2A-AD1 could simultaneously bind both the KIX and TAZ2 domains. However, we did not detect a ternary complex involving E2A-AD1, KIX, and TAZ2 and found that E2A containing both intact AD1 and AD2 is required to bind to CBP/p300. Our findings highlight the structural plasticity and promiscuity of E2A-AD1 and suggest that E2A binds both the TAZ2 and KIX domains of CBP/p300 through AD1 and AD2.
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Affiliation(s)
- Marina R Lochhead
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Alexandra D Brown
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Alyssa C Kirlin
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Seth Chitayat
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Kim Munro
- Protein Function Discovery Group, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Jane E Findlay
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - George S Baillie
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - David P LeBrun
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - David N Langelaan
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada; Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada.
| | - Steven P Smith
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada; Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada.
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4
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Maharjan BD, Ono R, Nosaka T. Eya2 is critical for the E2A‑HLF‑mediated immortalization of mouse hematopoietic stem/progenitor cells. Int J Oncol 2019; 54:981-990. [PMID: 30628662 DOI: 10.3892/ijo.2019.4673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 11/09/2018] [Indexed: 11/05/2022] Open
Abstract
The immunoglobulin enhancer‑binding factor/hepatic leukemia factor (E2A‑HLF) oncogenic fusion gene, generated by t(17;19)(q22;p13) translocation in childhood B‑cell acute lymphoblastic leukemia with a very poor prognosis, encodes a chimeric transcription factor in which the transactivation domains of E2A are fused to the DNA‑binding and dimerization domain of HLF. E2A‑HLF has been demonstrated to have an anti‑apoptotic effect. However, the molecular mechanism underlying E2A‑HLF‑mediated leukemogenesis remains unclear. The present study identified EYA transcriptional coactivator and phosphatase 2 (Eya2), the forced expression of which is known to immortalize mouse hematopoietic stem/progenitor cells (HSPCs), as a direct target molecule downstream of E2A‑HLF. E2A‑HLF‑immortalized mouse HSPCs expressed Eya2 at a high level in the aberrant self‑renewal program. Chromatin immunoprecipitation‑quantitative polymerase chain reaction and a reporter assay revealed that E2A‑HLF enhanced the Eya2 expression by binding to the promoter region containing the E2A‑HLF‑binding consensus sequence. Eya2 knockdown in E2A‑HLF‑immortalized cells resulted in reduced colony‑forming efficiency. These results suggest a critical role of Eya2 in E2A‑HLF‑mediated leukemogenesis.
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Affiliation(s)
- Bishnu Devi Maharjan
- Department of Microbiology and Molecular Genetics, Mie University Graduate School of Medicine, Tsu 514‑8507, Japan
| | - Ryoichi Ono
- Department of Microbiology and Molecular Genetics, Mie University Graduate School of Medicine, Tsu 514‑8507, Japan
| | - Tetsuya Nosaka
- Department of Microbiology and Molecular Genetics, Mie University Graduate School of Medicine, Tsu 514‑8507, Japan
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5
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Blume J, Ziętara N, Witzlau K, Liu Y, Sanchez OO, Puchałka J, Winter SJ, Kunze-Schumacher H, Saran N, Düber S, Roy B, Weiss S, Klein C, Wurst W, Łyszkiewicz M, Krueger A. miR-191 modulates B-cell development and targets transcription factors E2A, Foxp1, and Egr1. Eur J Immunol 2018; 49:121-132. [PMID: 30281154 DOI: 10.1002/eji.201847660] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 09/17/2018] [Accepted: 10/01/2018] [Indexed: 01/07/2023]
Abstract
The interdependence of posttranscriptional gene regulation via miRNA and transcriptional regulatory networks in lymphocyte development is poorly understood. Here, we identified miR-191 as direct upstream modulator of a transcriptional module comprising the transcription factors Foxp1, E2A, and Egr1. Deletion as well as ectopic expression of miR-191 resulted in developmental arrest in B lineage cells, indicating that fine tuning of the combined expression levels of Foxp1, E2A, and Egr1, which in turn control somatic recombination and cytokine-driven expansion, constitutes a prerequisite for efficient B-cell development. In conclusion, we propose that miR-191 acts as a rheostat in B-cell development by fine tuning a key transcriptional program.
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Affiliation(s)
- Jonas Blume
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Natalia Ziętara
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Katrin Witzlau
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Yanshan Liu
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | | | - Jacek Puchałka
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Samantha J Winter
- Institute for Molecular Medicine, Goethe University Frankfurt, Frankfurt, Germany
| | | | - Namita Saran
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Sandra Düber
- Molecular Immunology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Bishnudeo Roy
- Molecular Immunology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Siegfried Weiss
- Institute of Immunology, Hannover Medical School, Hannover, Germany.,Molecular Immunology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Christoph Klein
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Centre Munich, Germany.,Technische Universität München-Weihenstephan, Neuherberg/Munich, Germany.,German Center for Neurodegenerative Diseases (DZNE), Site Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Marcin Łyszkiewicz
- Institute of Immunology, Hannover Medical School, Hannover, Germany.,Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Andreas Krueger
- Institute of Immunology, Hannover Medical School, Hannover, Germany.,Institute for Molecular Medicine, Goethe University Frankfurt, Frankfurt, Germany
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6
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Zhou X, Xian W, Zhang J, Zhu Y, Shao X, Han Y, Qi Y, Ding X, Wang X. YY1 binds to the E3' enhancer and inhibits the expression of the immunoglobulin κ gene via epigenetic modifications. Immunology 2018; 155:491-498. [PMID: 30098214 DOI: 10.1111/imm.12990] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 06/08/2018] [Accepted: 06/22/2018] [Indexed: 01/11/2023] Open
Abstract
The rearrangement and expression of immunoglobulin genes are regulated by enhancers and their binding transcriptional factors that activate or suppress the activities of the enhancers. The immunoglobulin κ (Igκ) gene locus has three important enhancers: the intrinsic enhancer (Ei), 3' enhancer (E3'), and distal enhancer (Ed). Ei and E3' are both required for Igκ gene rearrangement during early stages of B-cell development, whereas optimal expression of the rearranged Igκ gene relies on both E3' and Ed. The transcription factor YY1 affects the expression of many genes involved in B-cell development, probably by mediating interactions between their enhancers and promoters. Herein, we found that YY1 binds to the E3' enhancer and suppresses Igκ expression in B lymphoma cells by epigenetically modifying the enhancer. Knocking down YY1 enhanced Igκ expression, which was associated with increased levels of E2A (encoded by the TCF3 gene) and its binding to the E3' enhancer. Moreover, in germinal centre B cells and plasma cells, YY1 expression was reversely associated with Igκ levels, implying that YY1 might facilitate antibody affinity maturation in germinal centre B cells through the transient attenuation of Igκ expression.
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Affiliation(s)
- Xiaorong Zhou
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Weiwei Xian
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Jie Zhang
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Yiqing Zhu
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Xiaoyi Shao
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Yu Han
- Department of Occupational Medicine and Environmental Hygiene, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Yue Qi
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Xiaoling Ding
- Department of Gastroenterology, The Affiliated Hospital of Nantong University, Nantong, Jiangsu, China
| | - Xiaoying Wang
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu, China
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7
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Paradoxical role of Id proteins in regulating tumorigenic potential of lymphoid cells. Front Med 2018; 12:374-386. [PMID: 30043222 DOI: 10.1007/s11684-018-0652-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 06/26/2018] [Indexed: 12/11/2022]
Abstract
A family of transcription factors known as Id proteins, or inhibitor of DNA binding and differentiation, is capable of regulating cell proliferation, survival and differentiation, and is often upregulated in multiple types of tumors. Due to their ability to promote self-renewal, Id proteins have been considered as oncogenes, and potential therapeutic targets in cancer models. On the contrary, certain Id proteins are reported to act as tumor suppressors in the development of Burkitt's lymphoma in humans, and hepatosplenic and innate-like T cell lymphomas in mice. The contexts and mechanisms by which Id proteins can serve in such contradictory roles to determine tumor outcomes are still not well understood. In this review, we explore the roles of Id proteins in lymphocyte development and tumorigenesis, particularly with respect to inhibition of their canonical DNA binding partners known as E proteins. Transcriptional regulation by E proteins, and their antagonism by Id proteins, act as gatekeepers to ensure appropriate lymphocyte development at key checkpoints. We re-examine the derailment of these regulatory mechanisms in lymphocytes that facilitate tumor development. These mechanistic insights can allow better appreciation of the context-dependent roles of Id proteins in cancers and improve considerations for therapy.
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8
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Sauer CM, Chteinberg E, Rennspiess D, Kurz AK, Zur Hausen A. [Merkel cell carcinoma: cutaneous manifestation of a highly malignant pre-/pro-B cell neoplasia? : Novel concept about the cellular origin of Merkel cell carcinoma]. Hautarzt 2017; 68:204-210. [PMID: 28194491 DOI: 10.1007/s00105-017-3945-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Merkel cell carcinoma (MCC) is a relatively rare but highly malignant non-melanoma skin cancer of the elderly and immunosuppressed patients. The discovery of the Merkel cell polyomavirus (MCPyV) in 2008 significantly impacted the understanding of the etiopathogenesis of MCC. MCPyV is clonally integrated into the MCC genome and approximately 80% of MCC are MCPyV-positive. Recent results of clinical trials using blockade of the PD-1 immune modulatory pathway are promising for the future treatment of MCC. Despite this major progress of the past few years, the cellular origin of MCC still remains obscure. Based on histomorphology, gene expression profiling, and molecular analyses, we have recently hypothesized that MCC originates from pre‑/pro-B cells. Here we review putative cells of MCC, including Merkel cells, (epi‑)dermal stem cells, and pro‑/pre-B cells. In the present work, the focus is on the concept of pre‑/pro-B cells as the cellular origin of MCC, which might also impact the understanding of other human small cell malignancies of unknown cellular origin, such as small cell carcinomas of the lung and other anatomical locations. In addition, this concept might pave the way for novel treatment options, especially for advanced MCC.
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Affiliation(s)
- C M Sauer
- Department of Pathology, GROW-School for Oncology & Developmental Biology, Maastricht University Medical Centre, P. Debyelaan 25, 6229 HX, Maastricht, Netherlands.,Department of Internal Medicine IV, University Hospital Aachen, Aachen, Deutschland
| | - E Chteinberg
- Department of Pathology, GROW-School for Oncology & Developmental Biology, Maastricht University Medical Centre, P. Debyelaan 25, 6229 HX, Maastricht, Netherlands
| | - D Rennspiess
- Department of Pathology, GROW-School for Oncology & Developmental Biology, Maastricht University Medical Centre, P. Debyelaan 25, 6229 HX, Maastricht, Netherlands
| | - A K Kurz
- Department of Internal Medicine IV, University Hospital Aachen, Aachen, Deutschland
| | - A Zur Hausen
- Department of Pathology, GROW-School for Oncology & Developmental Biology, Maastricht University Medical Centre, P. Debyelaan 25, 6229 HX, Maastricht, Netherlands.
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9
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Hauser J, Grundström C, Kumar R, Grundström T. Regulated localization of an AID complex with E2A, PAX5 and IRF4 at the Igh locus. Mol Immunol 2016; 80:78-90. [DOI: 10.1016/j.molimm.2016.10.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 10/25/2016] [Accepted: 10/27/2016] [Indexed: 12/11/2022]
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10
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Masuda J, Kawamoto H, Strober W, Takayama E, Mizutani A, Murakami H, Ikawa T, Kitani A, Maeno N, Shigehiro T, Satoh A, Seno A, Arun V, Kasai T, Fuss IJ, Katsura Y, Seno M. Transient Tcf3 Gene Repression by TALE-Transcription Factor Targeting. Appl Biochem Biotechnol 2016; 180:1559-1573. [PMID: 27406037 DOI: 10.1007/s12010-016-2187-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 07/04/2016] [Indexed: 12/14/2022]
Abstract
Transplantation of hematopoietic stem and progenitor cells (HSCs) i.e., self-renewing cells that retain multipotentiality, is now a widely performed therapy for many hematopoietic diseases. However, these cells are present in low number and are subject to replicative senescence after extraction; thus, the acquisition of sufficient numbers of cells for transplantation requires donors able to provide repetitive blood samples and/or methods of expanding cell numbers without disturbing cell multipotentiality. Previous studies have shown that HSCs maintain their multipotentiality and self-renewal activity if TCF3 transcription function is blocked under B cell differentiating conditions. Taking advantage of this finding to devise a new approach to HSC expansion in vitro, we constructed an episomal expression vector that specifically targets and transiently represses the TCF3 gene. This consisted of a vector encoding a transcription activator-like effector (TALE) fused to a Krüppel-associated box (KRAB) repressor. We showed that this TALE-KRAB vector repressed expression of an exogenous reporter gene in HEK293 and COS-7 cell lines and, more importantly, efficiently repressed endogenous TCF3 in a human B lymphoma cell line. These findings suggest that this vector can be used to maintain multipotentiality in HSC being subjected to a long-term expansion regimen prior to transplantation.
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Affiliation(s)
- Junko Masuda
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.
- Mucosal Immunity Section, Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Hiroshi Kawamoto
- Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama, 230-0045, Japan
- Department of Immunology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, 606-8507, Japan
| | - Warren Strober
- Mucosal Immunity Section, Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Eiji Takayama
- Department of Oral Biochemistry, Asahi University School of Dentistry, Hozumi 1851, Gifu, 501-0296, Japan
| | - Akifumi Mizutani
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Hiroshi Murakami
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Tomokatsu Ikawa
- Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama, 230-0045, Japan
- Laboratory for Immune Regeneration, RIKEN Center for Integrative Medical Sciences, Yokohama, 230-0045, Japan
| | - Atsushi Kitani
- Mucosal Immunity Section, Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Narumi Maeno
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Tsukasa Shigehiro
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Ayano Satoh
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Akimasa Seno
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Vaidyanath Arun
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Tomonari Kasai
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Ivan J Fuss
- Mucosal Immunity Section, Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Yoshimoto Katsura
- Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama, 230-0045, Japan
- Division of Cell Regeneration and Transplantation, Advanced Medical Research Center, School of Medicine, Nihon University, Tokyo, 173-8610, Japan
| | - Masaharu Seno
- Division of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
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11
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Manoharan A, Du Roure C, Rolink AG, Matthias P. De novo DNA Methyltransferases Dnmt3a and Dnmt3b regulate the onset of Igκ light chain rearrangement during early B-cell development. Eur J Immunol 2015; 45:2343-55. [PMID: 26059604 DOI: 10.1002/eji.201445035] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 04/24/2015] [Accepted: 05/19/2015] [Indexed: 02/01/2023]
Abstract
Immunoglobulin genes V(D)J rearrangement during early lymphopoiesis is a critical process involving sequential recombination of the heavy and light chain loci. A number of transcription factors act together with temporally activated recombinases and chromatin accessibility changes to regulate this complex process. Here, we deleted the de novo DNA methyltransferases Dnmt3a and Dnmt3b in early B cells of conditionally targeted mice, and monitored the process of V(D)J recombination. Dnmt3a and Dnmt3b deletion resulted in precocious recombination of the immunoglobulin κ light chain without impairing the differentiation of mature B cells or overall B-cell development. Ex vivo culture of IL-7 restricted early B-cell progenitors lacking Dnmt3a and Dnmt3b showed precocious Vκ-Jκ rearrangements that are limited to the proximal Vκ genes. Furthermore, B-cell progenitors deficient in Dnmt3a and Dnmt3b showed elevated levels of germline transcripts at the proximal Vκ genes, alterations in methylation patterns at Igκ enhancer sites and increased expression of the transcription factor E2A. Our data suggest that Dnmt3a and Dnmt3b are critical to regulate the onset of Igκ light chain rearrangement during early B-cell development.
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Affiliation(s)
- Anand Manoharan
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Camille Du Roure
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | | | - Patrick Matthias
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- Faculty of Sciences, University of Basel, Basel, Switzerland
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12
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de Almeida CR, Hendriks RW, Stadhouders R. Dynamic Control of Long-Range Genomic Interactions at the Immunoglobulin κ Light-Chain Locus. Adv Immunol 2015; 128:183-271. [DOI: 10.1016/bs.ai.2015.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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13
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Expression and recruitment of uracil-DNA glycosylase are regulated by E2A during antibody diversification. Mol Immunol 2014; 60:23-31. [DOI: 10.1016/j.molimm.2014.03.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 03/24/2014] [Indexed: 11/20/2022]
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14
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Denis CM, Langelaan DN, Kirlin AC, Chitayat S, Munro K, Spencer HL, LeBrun DP, Smith SP. Functional redundancy between the transcriptional activation domains of E2A is mediated by binding to the KIX domain of CBP/p300. Nucleic Acids Res 2014; 42:7370-82. [PMID: 24682819 PMCID: PMC4066744 DOI: 10.1093/nar/gku206] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The E-protein transcription factors play essential roles in lymphopoiesis, with E12 and E47 (hereafter called E2A) being particularly important in B cell specification and maturation. The E2A gene is also involved in a chromosomal translocation that results in the leukemogenic oncoprotein E2A-PBX1. The two activation domains of E2A, AD1 and AD2, display redundant, independent, and cooperative functions in a cell-dependent manner. AD1 of E2A functions by binding the transcriptional co-activator CBP/p300; this interaction is required in oncogenesis and occurs between the conserved ϕ-x-x-ϕ-ϕ motif in AD1 and the KIX domain of CBP/p300. However, co-activator recruitment by AD2 has not been characterized. Here, we demonstrate that the first of two conserved ϕ-x-x-ϕ-ϕ motifs within AD2 of E2A interacts at the same binding site on KIX as AD1. Mutagenesis uncovered a correspondence between the KIX-binding affinity of AD2 and transcriptional activation. Although AD2 is dispensable for oncogenesis, experimentally increasing the affinity of AD2 for KIX uncovered a latent potential to mediate immortalization of primary hematopoietic progenitors by E2A-PBX1. Our findings suggest that redundancy between the two E2A activation domains with respect to transcriptional activation and oncogenic function is mediated by binding to the same surface of the KIX domain of CBP/p300.
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Affiliation(s)
- Christopher M Denis
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - David N Langelaan
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Alyssa C Kirlin
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Seth Chitayat
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Kim Munro
- Protein Function Discovery Group, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Holly L Spencer
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - David P LeBrun
- Protein Function Discovery Group, Queen's University, Kingston, Ontario, K7L 3N6, Canada Department of Pathology and Molecular Medicine, Queen's University, Kingston, Ontario, K7L 3N6, Canada Division of Cancer Biology and Genetics, Cancer Research Institute, Queen's University, Kingston, Ontario, K7L 3N6, Canada
| | - Steven P Smith
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, K7L 3N6, Canada Protein Function Discovery Group, Queen's University, Kingston, Ontario, K7L 3N6, Canada
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15
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Yu L, Zhang YD, Zhou J, Yao DM, Li X. Identification of target genes of transcription factor CEBPB in acute promyelocytic leukemia cells induced by all-trans retinoic acid. ASIAN PAC J TROP MED 2014; 6:473-80. [PMID: 23711709 DOI: 10.1016/s1995-7645(13)60077-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Revised: 03/15/2013] [Accepted: 04/15/2013] [Indexed: 10/26/2022] Open
Abstract
OBJECTIVE To identify target genes of transcription factor CCAAT enhancer-binding protein β (CEBPB) in acute promyelocytic leukemia cells induced by all-trans retinoic acid. METHODS A new strategy for high-throughput identification of direct target genes was established by combining chromatin immunoprecipitation (ChIP) with in vitro selection. Then, 106 potential CEBPB binding fragments from the genome of the all-trans retinoic acid (ATRA)-treated NB4 cells were identified. RESULTS Of them, 82 were mapped in proximity to known or previously predicted genes; 7 were randomly picked up for further confirmation by ChIP-PCR and 3 genes (GALM, ITPR2 and ORM2) were found to be specifically up-regulated in the ATRA-treated NB4 cells, indicating that they might be the down-stream target genes of ATRA. CONCLUSIONS Our results provided new insight into the mechanisms of ATRA-induced granulocytic differentiation.
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Affiliation(s)
- Lei Yu
- Department of Hepatic Surgery, National Hepatobiliary and Enteric Surgery Research Center, Ministry of Health, Central South University, China
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16
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Stadhouders R, de Bruijn MJW, Rother MB, Yuvaraj S, de Almeida CR, Kolovos P, Van Zelm MC, van Ijcken W, Grosveld F, Soler E, Hendriks RW. Pre-B cell receptor signaling induces immunoglobulin κ locus accessibility by functional redistribution of enhancer-mediated chromatin interactions. PLoS Biol 2014; 12:e1001791. [PMID: 24558349 PMCID: PMC3928034 DOI: 10.1371/journal.pbio.1001791] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 01/08/2014] [Indexed: 12/13/2022] Open
Abstract
Chromatin conformation analyses provide novel insights into how variable segments in the immunoglobulin light chain gene become accessible for recombination in precursor B lymphocytes. During B cell development, the precursor B cell receptor (pre-BCR) checkpoint is thought to increase immunoglobulin κ light chain (Igκ) locus accessibility to the V(D)J recombinase. Accordingly, pre-B cells lacking the pre-BCR signaling molecules Btk or Slp65 showed reduced germline Vκ transcription. To investigate whether pre-BCR signaling modulates Vκ accessibility through enhancer-mediated Igκ locus topology, we performed chromosome conformation capture and sequencing analyses. These revealed that already in pro-B cells the κ enhancers robustly interact with the ∼3.2 Mb Vκ region and its flanking sequences. Analyses in wild-type, Btk, and Slp65 single- and double-deficient pre-B cells demonstrated that pre-BCR signaling reduces interactions of both enhancers with Igκ locus flanking sequences and increases interactions of the 3′κ enhancer with Vκ genes. Remarkably, pre-BCR signaling does not significantly affect interactions between the intronic enhancer and Vκ genes, which are already robust in pro-B cells. Both enhancers interact most frequently with highly used Vκ genes, which are often marked by transcription factor E2a. We conclude that the κ enhancers interact with the Vκ region already in pro-B cells and that pre-BCR signaling induces accessibility through a functional redistribution of long-range chromatin interactions within the Vκ region, whereby the two enhancers play distinct roles. B lymphocyte development involves the generation of a functional antigen receptor, comprising two heavy chains and two light chains arranged in a characteristic “Y” shape. To do this, the receptor genes must first be assembled by ordered genomic recombination events, starting with the immunoglobulin heavy chain (IgH) gene segments. On successful rearrangement, the resulting IgH μ protein is presented on the cell surface as part of a preliminary version of the B cell receptor—the “pre-BCR.” Pre-BCR signaling then redirects recombination activity to the immunoglobulin κ light chain gene. The activity of two regulatory κ enhancer elements is known to be crucial for opening up the gene, but it remains largely unknown how the hundred or so Variable (V) segments in the κ locus gain access to the recombination system. Here, we studied a panel of pre-B cells from mice lacking specific signaling molecules, reflecting absent, partial, or complete pre-BCR signaling. We identify gene regulatory changes that are dependent on pre-BCR signaling and occur via long-range chromatin interactions between the κ enhancers and the V segments. Surprisingly the light chain gene initially contracts, but the interactions then become more functionally redistributed when pre-BCR signaling occurs. Interestingly, we find that the two enhancers play distinct roles in the process of coordinating chromatin interactions towards the V segments. Our study combines chromatin conformation techniques with data on transcription factor binding to gain unique insights into the functional role of chromatin dynamics.
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MESH Headings
- Animals
- Cells, Cultured
- Chromatin/genetics
- Chromatin/metabolism
- Chromatin Assembly and Disassembly
- Enhancer Elements, Genetic
- Epistasis, Genetic
- Histones/metabolism
- Immunoglobulin kappa-Chains/genetics
- Immunoglobulin kappa-Chains/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Precursor Cells, B-Lymphoid/metabolism
- Protein Processing, Post-Translational
- Receptors, Antigen, B-Cell/genetics
- Receptors, Antigen, B-Cell/metabolism
- Signal Transduction
- Transcriptome
- V(D)J Recombination
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Affiliation(s)
| | | | | | - Saravanan Yuvaraj
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, The Netherlands
| | | | - Petros Kolovos
- Department of Cell Biology, Erasmus MC Rotterdam, The Netherlands
| | | | | | - Frank Grosveld
- Department of Cell Biology, Erasmus MC Rotterdam, The Netherlands
- The Cancer Genomics Center, Erasmus MC Rotterdam, The Netherlands
| | - Eric Soler
- Department of Cell Biology, Erasmus MC Rotterdam, The Netherlands
- The Cancer Genomics Center, Erasmus MC Rotterdam, The Netherlands
- INSERM UMR967 and French Alternative Energies and Atomic Energy Commission (CEA), Fontenay-aux-Roses, France
| | - Rudi W. Hendriks
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, The Netherlands
- * E-mail:
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17
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Hauser J, Grundström C, Grundström T. Allelic exclusion of IgH through inhibition of E2A in a VDJ recombination complex. THE JOURNAL OF IMMUNOLOGY 2014; 192:2460-70. [PMID: 24470503 DOI: 10.4049/jimmunol.1302216] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A key feature of the immune system is the paradigm that one lymphocyte has only one Ag specificity that can be selected for or against. This requires that only one of the alleles of genes for AgR chains is made functional. However, the molecular mechanism of this allelic exclusion has been an enigma. In this study, we show that B lymphocytes with E2A that cannot be inhibited by calmodulin are dramatically defective in allelic exclusion of the IgH locus. Furthermore, we provide data supporting that E2A, PAX5, and the RAGs are in a VDJ recombination complex bound to key sequences on the Igh gene. We show that pre-BCR activation releases the VDJ recombination complex through calmodulin binding to E2A. We also show that pre-BCR signaling downregulates several components of the recombination machinery, including RAG1, RAG2, and PAX5, through calmodulin inhibition of E2A.
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Affiliation(s)
- Jannek Hauser
- Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden
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18
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Abstract
E-proteins are critical transcription factors in B-cell lymphopoiesis. E2A, 1 of 3 E-protein-encoding genes, is implicated in the induction of acute lymphoblastic leukemia through its involvement in the chromosomal translocation 1;19 and consequent expression of the E2A-PBX1 oncoprotein. An interaction involving a region within the N-terminal transcriptional activation domain of E2A-PBX1, termed the PCET motif, which has previously been implicated in E-protein silencing, and the KIX domain of the transcriptional coactivator CBP/p300, critical for leukemogenesis. However, the structural details of this interaction remain unknown. Here we report the structure of a 1:1 complex between PCET motif peptide and the KIX domain. Residues throughout the helical PCET motif that contact the KIX domain are important for both binding KIX and bone marrow immortalization by E2A-PBX1. These results provide molecular insights into E-protein-driven differentiation of B-cells and the mechanism of E-protein silencing, and reveal the PCET/KIX interaction as a therapeutic target for E2A-PBX1-induced leukemia.
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19
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miR290-5p/292-5p activate the immunoglobulin kappa locus in B cell development. PLoS One 2012; 7:e43805. [PMID: 22928038 PMCID: PMC3426528 DOI: 10.1371/journal.pone.0043805] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 07/26/2012] [Indexed: 01/09/2023] Open
Abstract
Regulated expression of miRNAs influences development in a wide variety of contexts. We report here that miR290-5p (100049710) and miR292-5p (100049711) are induced at the pre-B stage of murine B cell development and that they influence assembly of the Igκ light chain gene (243469) by contributing to the activation of germline Igκ transcription (κGT). We found that upon forced over-expression of miR290-5p/292-5p in Abelson Murine Leukemia Virus (AMuLV) transformed pro-B cells, two known activators of κGT, E2A (21423) and NF-κB (19697), show increased chromosomal binding to the kappa intronic enhancer. Conversely, knockdown of miR290-5p/292-5p in AMuLV pro-B cells blunts drug-induced activation of κGT. Furthermore, miR290-5p/292-5p knockdown also diminishes κGT activation, but not Rag1/2 (19373, 19374) expression, in an IL-7 dependent primary pro-B cell culture system. In addition, we identified a deficiency in κGT induction in miR290 cluster knockout mice. We hypothesize that increased expression of miR290-5p and miR292-5p contributes to the induction of κGT at the pre-B stage of B cell development through increased binding of NF-κB and E2A to kappa locus regulatory sequences.
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20
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Sakamoto S, Wakae K, Anzai Y, Murai K, Tamaki N, Miyazaki M, Miyazaki K, Romanow WJ, Ikawa T, Kitamura D, Yanagihara I, Minato N, Murre C, Agata Y. E2A and CBP/p300 Act in Synergy To Promote Chromatin Accessibility of the Immunoglobulin κ Locus. THE JOURNAL OF IMMUNOLOGY 2012; 188:5547-60. [DOI: 10.4049/jimmunol.1002346] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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21
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Biochemical and phosphoproteomic analysis of the helix-loop-helix protein E47. Mol Cell Biol 2012; 32:1671-82. [PMID: 22354994 DOI: 10.1128/mcb.06452-11] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Numerous in vitro as well as genetic studies have demonstrated that the activities of the E2A proteins are regulated at multiple levels, including modulation of DNA binding by the Id proteins, association with the transcriptional modulators p300 and ETO, and posttranslational modifications. Here, we use affinity purification of tagged E47 combined with mass spectrometry in order to show that E47 interacts with the entire ensemble of Id proteins, namely, Id1, Id2, Id3, and Id4. Furthermore, we find that the lysine-specific histone demethylase 1 (LSD1), the protein arginine N-methyltransferase 5 (PRMT5), the corepressor CoREST, and the chaperones of the 14-3-3 family associate with affinity-purified E47. We also identify a spectrum of amino acid residues in E47 that are phosphorylated, including an AKT substrate site. We did, however, find that mutation of the identified AKT substrate site by itself did not perturb B cell development. In sum, these studies show that the entire ensemble of Id proteins has the ability to interact with E47, identify factors that associate with E47, and reveal a spectrum of phosphorylated residues in E47, including an AKT substrate site.
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22
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Green YS, Vetter ML. EBF proteins participate in transcriptional regulation of Xenopus muscle development. Dev Biol 2011; 358:240-50. [PMID: 21839736 DOI: 10.1016/j.ydbio.2011.07.034] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 07/24/2011] [Accepted: 07/27/2011] [Indexed: 01/08/2023]
Abstract
EBF proteins have diverse functions in the development of multiple lineages, including neurons, B cells and adipocytes. During Drosophila muscle development EBF proteins are expressed in muscle progenitors and are required for muscle cell differentiation, but there is no known function of EBF proteins in vertebrate muscle development. In this study, we examine the expression of ebf genes in Xenopus muscle tissue and show that EBF activity is necessary for aspects of Xenopus skeletal muscle development, including somite organization, migration of hypaxial muscle anlagen toward the ventral abdomen, and development of jaw muscle. From a microarray screen, we have identified multiple candidate targets of EBF activity with known roles in muscle development. The candidate targets we have verified are MYOD, MYF5, M-Cadherin and SEB-4. In vivo overexpression of the ebf2 and ebf3 genes leads to ectopic expression of these candidate targets, and knockdown of EBF activity causes downregulation of the endogenous expression of the candidate targets. Furthermore, we found that MYOD and MYF5 are likely to be direct targets. Finally we show that MYOD can upregulate the expression of ebf genes, indicating the presence of a positive feedback loop between EBF and MYOD that we find to be important for maintenance of MYOD expression in Xenopus. These results suggest that EBF activity is important for both stabilizing commitment and driving aspects of differentiation in Xenopus muscle cells.
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Affiliation(s)
- Yangsook Song Green
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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23
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Abstract
Lymphopoiesis generates mature B, T, and NK lymphocytes from hematopoietic stem cells via a series of increasingly restricted developmental intermediates. The transcriptional networks that regulate these fate choices are composed of both common and lineage-specific components, which combine to create a cellular context that informs the developmental response to external signals. E proteins are an important factor during lymphopoiesis, and E2A in particular is required for normal T- and B-cell development. Although the other E proteins, HEB and E2-2, are expressed during lymphopoiesis and can compensate for some of E2A's activity, E2A proteins have non-redundant functions during early T-cell development and at multiple checkpoints throughout B lymphopoiesis. More recently, a role for E2A has been demonstrated in the generation of lymphoid-primed multipotent progenitors and shown to favor their specification toward lymphoid over myeloid lineages. This review summarizes both our current understanding of the wide-ranging functions of E proteins during the development of adaptive lymphocytes and the novel functions of E2A in orchestrating a lymphoid-biased cellular context in early multipotent progenitors.
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Affiliation(s)
- Renée F de Pooter
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
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24
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Forced expression of cyclin-dependent kinase 6 confers resistance of pro-B acute lymphocytic leukemia to Gleevec treatment. Mol Cell Biol 2011; 31:2566-76. [PMID: 21536647 DOI: 10.1128/mcb.01349-10] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The gene encoding c-ABL, a nonreceptor protein tyrosine kinase, is involved in a chromosomal translocation resulting in expression of a BCR-Abl fusion protein that causes most chronic myelogenous and some acute lymphocytic leukemias (CML and ALL) in humans. The Abelson murine leukemia virus (A-MuLV) expresses an alternative form of c-Abl, v-Abl, that transforms murine pro-B cells, resulting in acute leukemia and providing an experimental model for human disease. Gleevec (STI571) inhibits the Abl kinase and has shown great utility against CML and ALL in humans, although its usefulness is limited by acquired resistance. Since STI571 is active against A-MuLV-transformed cells in vitro, we performed a retroviral cDNA library screen for genes that confer resistance to apoptosis induced by STI571. We found that forced expression of Cdk6 promotes continued cell division and decreased apoptosis of leukemic cells. We then determined that the transcription factor E2A negatively regulates Cdk6 transcription in leukemic pro-B cells and that the v-Abl kinase stimulates Cdk6 expression via an extracellular signal-regulated kinase 1-dependent pathway. Finally, we show that the cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor PD0332991 can act synergistically with STI571 to enhance leukemic cell death, suggesting a potential role for CDK6 inhibitors in the treatment of STI571-resistant CML or ALL.
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25
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Abstract
CD38, a nucleotide-metabolizing ectoenzyme and a receptor, is a negative prognostic marker for chronic lymphocytic leukemia (CLL) patients. CD38 has a genetic polymorphism, with a C → G variation in a putative E-box located in a regulatory region. E2A, the predominant E-box factor in B lymphocytes, was found to be highly expressed by CD38(+) CLL patients. The highest CD38 levels scored by E2A(+)/G carrier patients suggested that E2A is (i) directly associated with CD38 expression, and that (ii) the binding of the transcription factor is influenced by the CD38 genotype. Chromatin immunoprecipitation indicated that E2A directly interacts with the CD38 regulatory region. Furthermore, E2A binding was stronger in the presence of the G allele. Experiments of E2A silencing led to a significant reduction of surface levels of CD38, confirming the working hypothesis. A direct functional interplay between E2A and CD38 was shown by exposing CLL cells to interleukin-2 and TLR-9 ligands, both inducers of CD38 expression. Under these conditions, CD38 upregulation was primarily conditioned by the presence of E2A and then by the G allele. The results of this study link E2A and CD38 expression within a common pathway, in which E-protein activity is required for the efficient induction of CD38 transcription.
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26
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Pinaud E, Marquet M, Fiancette R, Péron S, Vincent-Fabert C, Denizot Y, Cogné M. The IgH locus 3' regulatory region: pulling the strings from behind. Adv Immunol 2011; 110:27-70. [PMID: 21762815 DOI: 10.1016/b978-0-12-387663-8.00002-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Antigen receptor gene loci are among the most complex in mammals. The IgH locus, encoding the immunoglobulin heavy chain (IgH) in B-lineage cells, undergoes major transcription-dependent DNA remodeling events, namely V(D)J recombination, Ig class-switch recombination (CSR), and somatic hypermutation (SHM). Various cis-regulatory elements (encompassing promoters, enhancers, and chromatin insulators) recruit multiple nuclear factors in order to ensure IgH locus regulation by tightly orchestrated physical and/or functional interactions. Among major IgH cis-acting regions, the large 3' regulatory region (3'RR) located at the 3' boundary of the locus includes several enhancers and harbors an intriguing quasi-palindromic structure. In this review, we report progress insights made over the past decade in order to describe in more details the structure and functions of IgH 3'RRs in mouse and human. Generation of multiple cellular, transgenic and knock-out models helped out to decipher the function of the IgH 3' regulatory elements in the context of normal and pathologic B cells. Beside its interest in physiology, the challenge of elucidating the locus-wide cross talk between distant cis-regulatory elements might provide useful insights into the mechanisms that mediate oncogene deregulation after chromosomal translocations onto the IgH locus.
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Affiliation(s)
- Eric Pinaud
- UMR CNRS 6101, Centre National de la Recherche Scientifique, Université de Limoges, Limoges, France
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27
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Cochrane SW, Zhao Y, Perry SS, Urbaniak T, Sun XH. Id1 has a physiological role in regulating early B lymphopoiesis. Cell Mol Immunol 2010; 8:41-9. [PMID: 21200383 DOI: 10.1038/cmi.2010.58] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Basic helix-loop-helix E proteins play critical roles in B-cell development by stimulating B cell-specific gene expression and immunoglobulin gene rearrangement. The function of E proteins can be effectively suppressed by their naturally occurring inhibitors, Id1 to 4. Ectopic expression of Id1 has been shown to block B-cell development at the early pro-B cell stage. However, whether Id1 plays a physiological role in controlling B lymphopoiesis was not known. Although Id1-deficient mice do not exhibit significant abnormalities in steady-state B lymphopoiesis, we detected more robust B-cell engraftment in transplant recipients of Id1-deficient bone marrow compared to those of wild-type donor cells. In culture, Id1 ablation dramatically enhances B-lineage cell production without any marked effects on myeloid differentiation. Consistently, Id1 expression was found in pro-B but not pre-B cells as measured by enhanced green fluorescent protein (EGFP) fluorescence and by quantitative reverse transcription-PCR. Although loss of Id1 did not alter the number of B-cell colonies generated from whole bone marrow or the proliferation rate of developing B cells, B-cell colonies were detectable at a much earlier time point and the size of the colonies were larger. Therefore, we infer that Id1-deficient progenitors possess higher potential to differentiate to the pre-B cell stage when a proliferative burst occurs. Taken together, we present evidence to suggest that Id1 plays a physiological role in restraining the developmental progression, which may be important for proper B-cell differentiation in the bone marrow.
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Affiliation(s)
- Shawn W Cochrane
- Immunobiology and Cancer Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
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Novak R, Jacob E, Haimovich J, Avni O, Melamed D. The MAPK/ERK and PI3K pathways additively coordinate the transcription of recombination-activating genes in B lineage cells. THE JOURNAL OF IMMUNOLOGY 2010; 185:3239-47. [PMID: 20709952 DOI: 10.4049/jimmunol.1001430] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Rag-1 and Rag-2 are essential for the construction of the BCR repertoire. Regulation of Rag gene expression is tightly linked with BCR expression and signaling during B cell development. Earlier studies have shown a major role of the PI(3)K/Akt pathway in regulating the transcription of Rag genes. In this study, by using the 38c13 murine B cell lymphoma we show that transcription of Rag genes is also regulated by the MEK/ERK pathways, and that both pathways additively coordinate in this regulation. The additive effect is observed for both ligand-dependent (upon BCR ligation) and ligand independent (tonic) signals. However, whereas the PI(3)K/Akt regulation of Rag transcription is mediated by Foxo1, we show in this study that the MEK/ERK pathway coordinates with the regulation of Rag by controlling the phosphorylation and turnover of E47 and its consequential binding to the Rag enhancer regions. Our results suggest that the PI(3)K and MEK/ERK pathways additively coordinate in the regulation of Rag transcription in an independent manner.
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Affiliation(s)
- Rostislav Novak
- Department of Immunology, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
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Abstract
The intestine is subjected to a barrage of insults from food, bacterial flora, and pathogens. Despite this constant antigenic challenge, the mucosal tissues lining the intestinal tract remain largely under control. The mechanisms regulating the homeostatic balance in the gut have been investigated for many years by many groups, but the precise nature of the regulatory control remains elusive. In this review, we provide an overview of pathways proposed to be involved in dampening the inflammatory response and maintaining the homeostatic balance in the intestine, and how these pathways may be disrupted in ulcerative colitis and Crohn's disease.
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Beck K, Peak MM, Ota T, Nemazee D, Murre C. Distinct roles for E12 and E47 in B cell specification and the sequential rearrangement of immunoglobulin light chain loci. ACTA ACUST UNITED AC 2009; 206:2271-84. [PMID: 19752184 PMCID: PMC2757879 DOI: 10.1084/jem.20090756] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The E2A gene products, E12 and E47, are critical regulators of B cell development. However, it remains elusive whether E12 and E47 have overlapping and/or distinct functions during B lymphopoiesis. We have generated mice deficient for either E12 or E47 and examined their roles in B cell maturation. We show that E47 is essential for developmental progression at the prepro–B cell stage, whereas E12 is dispensable for early B cell development, commitment, and maintenance. In contrast, both E12 and E47 play critical roles in pre–B and immature B cells to promote immunoglobulin λ (Igλ) germline transcription as well as Igλ VJ gene rearrangement. Furthermore, we show that E12 as well as E47 is required to promote receptor editing upon exposure to self-antigen. We demonstrate that increasing levels of E12 and E47 act to induce Igλ germline transcription, promote trimethylated lysine 4 on histone 3 (H3) as well as H3 acetylation across the Jλ region, and activate Igλ VJ gene rearrangement. We propose that in the pre–B and immature B cell compartments, gradients of E12 and E47 activities are established to mechanistically regulate the sequential rearrangement of the Ig light chain genes.
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Affiliation(s)
- Kristina Beck
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
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31
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Ebf1-mediated down-regulation of Id2 and Id3 is essential for specification of the B cell lineage. Proc Natl Acad Sci U S A 2009; 106:552-7. [PMID: 19122139 DOI: 10.1073/pnas.0802550106] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Gene knockout experiments in mice have suggested a hierarchical model of early B cell commitment wherein E2A proteins (E47 and E12) activate early B cell factor (Ebf1), which in turn activates expression of the B cell commitment factor, Pax5. In IL-7 receptor alpha (IL-7Ralpha) knockout mice, B cell development is blocked before B-lineage commitment at the prepro-B cell stage in adult animals. In IL-7Ralpha(-/-) prepro-B cells, E47 is expressed and yet is insufficient to transcriptionally activate the putative downstream target gene, Ebf1. In this study, we show that further increases of E47 expression in IL-7Ralpha(-/-) prepro-B cells fails to activate Ebf1, but rather leads to a dramatic induction of the E2A inhibitory factors, Id2 and Id3. In contrast, enforced expression of Ebf1 in IL-7Ralpha(-/-) bone marrow potently down-regulates Id2 and Id3 mRNA expression and restores B cell differentiation in vivo. Down-regulation of both Id2 and Id3 during B cell specification is essential in that overexpression of either Id2 or Id3 in wild-type bone marrow blocks B cell specification at the prepro-B cell stage. Collectively, these studies suggest a model where Ebf1 induction specifies the B cell fate by dramatically increasing activity of E47 at the posttranslational level.
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32
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Regulation of V(D)J recombination by E-protein transcription factors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 650:148-56. [PMID: 19731808 DOI: 10.1007/978-1-4419-0296-2_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Extensive study of the E-proteins E2A and HEB duringlymphocyte development has revealed various functions for these bHLH transcription factors in regulating V(D)J recombination in both B- and T-cells. The study of E-proteins in mammals began with the identification of E2A by its ability to bind immunoglobulin heavy and light chain enhancers. Subsequent analysis has identified numerous roles for E2A and HEB at the immunoglobulin and T-cell receptor loci. E-protein targets also include the rag genes and other factors critical for recombination and for regulation of the developmental windows when cells undergo recombination. E-proteins appear to be master regulators that coordinate antigen receptor gene rearrangement and expression. This chapter focuses on how E-proteins regulate V(D)J recombination by activating transcription, initiating rearrangement and driving differentiation during B- and T-cell development.
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Abstract
Hematopoiesis consists of a series of lineage decisions controlled by specific gene expression that is regulated by transcription factors and intracellular signaling events in response to environmental cues. Here, we demonstrate that the balance between E-protein transcription factors and their inhibitors, Id proteins, is important for the myeloid-versus-lymphoid fate choice. Using Id1-GFP knockin mice, we show that transcription of the Id1 gene begins to be up-regulated at the granulocyte-macrophage progenitor stage and continues throughout myelopoiesis. Id1 expression is also stimulated by cytokines favoring myeloid differentiation. Forced expression of Id1 in multipotent progenitors promotes myeloid development and suppresses B-cell formation. Conversely, enhancing E-protein activity by expressing a variant of E47 resistant to Id-mediated inhibition prevents the myeloid cell fate while driving B-cell differentiation from lymphoid-primed multipotent progenitors. Together, these results suggest a crucial function for E proteins in the myeloid-versus-lymphoid lineage decision.
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35
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Regulation of lymphocyte development by cell-type-specific interpretation of Notch signals. Mol Cell Biol 2008; 28:2078-90. [PMID: 18195039 DOI: 10.1128/mcb.00844-07] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Notch signaling pathways exert diverse biological effects depending on the cellular context where Notch receptors are activated. How Notch signaling is integrated with environmental cues is a central issue. Here, we show that Notch activation accelerates ubiquitin-mediated and mitogen-activated protein kinase (MAPK)-dependent degradation of E2A transcription factors and Janus kinases, molecules essential for both B- and T-lymphocyte development. However, these events occur in B lymphocytes, but not T lymphocytes, due to their different levels of MAPK, thus providing one mechanism whereby Notch inhibits B-cell development without impairing T-cell differentiation. Lymphoid progenitors expressing a Notch-resistant E2A mutant differentiated into B-lineage cells on stromal cells expressing Notch ligands and in the thymus of transplant recipients. Bone marrow transplant assays and examination of steady-state B lymphopoiesis also revealed that the expression of Notch-resistant E2A and constitutively active STAT5 in mice neutralized the effects of Notch-induced degradation, allowing B-cell development through a bone marrow-like program in the thymus. These findings illustrate that Notch function can be influenced by MAPKs, producing distinct outcomes in different cellular contexts.
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36
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Cherrier M, D'Andon MF, Rougeon F, Doyen N. Identification of a new cis-regulatory element of the terminal deoxynucleotidyl transferase gene in the 5' region of the murine locus. Mol Immunol 2007; 45:1009-17. [PMID: 17854898 DOI: 10.1016/j.molimm.2007.07.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 07/26/2007] [Accepted: 07/27/2007] [Indexed: 10/22/2022]
Abstract
Terminal deoxynucleotidyl transferase (TdT) expression is controlled at the transcriptional level, however, the TdT core promoter combining D, D', an initiator (Inr) and downstream basal elements (DBE) does not recapitulate the whole complex regulation of TdT expression. We hypothesized that important cis-regulatory elements of the gene are located outside of the TdT promoter. In an attempt to identify these elements, we performed DNase I hypersensitivity assays over 24kb including a 10kb region located upstream of the transcription start site (+1) and a 14kb region spanning exons and introns I to VI. Hypersensitive sites (HS) HS1 and HS2 were localized 8.5 and 8kb upstream of the transcription start site, respectively, and were exclusively detected in TdT+ cell types. HS3, HS4 and HS5 were mapped at positions -7, -3.4 and -3kb, respectively, and detected in both TdT negative and positive cells. HS6, HS7 and HS8 were detected immediately upstream of the TdT promoter. HS10 and HS11 were localized in the first and third intron of the gene. Luciferase reporter assays revealed that HS1, HS2 and HS3 synergize with the TdT promoter to activate transcription in a TdT+ pre-T cell line but not in a TdT+ pro-B cell line. In summary novel cis-regulatory elements have been identified in the 5' region of the TdT locus that synergize with the promoter to activate gene expression and our results suggest these elements may be more active in T cells.
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Affiliation(s)
- Marie Cherrier
- Développement des tissus lymphoïdes, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France.
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Wojciechowski J, Lai A, Kondo M, Zhuang Y. E2A and HEB are required to block thymocyte proliferation prior to pre-TCR expression. THE JOURNAL OF IMMUNOLOGY 2007; 178:5717-26. [PMID: 17442955 PMCID: PMC2265380 DOI: 10.4049/jimmunol.178.9.5717] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Thymocytes undergoing TCRbeta gene rearrangements are maintained in a low or nonproliferating state during early T cell development. This block in cell cycle progression is not released until the expression of a functional pre-TCR, which is composed of a successfully rearranged TCRbeta-chain and the Pre-Talpha-chain. The regulatory molecules responsible for the coordination of these differentiation and proliferation events are currently unknown. E2A and HEB are structurally and functionally related basic helix-loop-helix transcription factors involved in T cell development. To reveal the function of E2A and HEB through the stage of pre-TCR expression and alleviate functional compensation between E2A and HEB, we use a double-conditional knockout model. The simultaneous deletion of E2A and HEB in developing thymocytes leads to a severe developmental block before pre-TCR expression and a dramatic reduction of Pre-Talpha expression. These developmentally arrested thymocytes exhibit increased proliferation in vivo and dramatic expansion ex vivo in response to IL-7 signaling. These results suggest that E2A and HEB are not only critical for T cell differentiation but also necessary to retain developing thymocytes in cell cycle arrest before pre-TCR expression.
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Affiliation(s)
| | | | | | - Yuan Zhuang
- Address correspondence and reprint requests to Dr. Yuan Zhuang, Duke University, Department of Immunology, DUMC 3010, Durham, NC 27710. E-mail address:
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Lin D, Ippolito GC, Zong RT, Bryant J, Koslovsky J, Tucker P. Bright/ARID3A contributes to chromatin accessibility of the immunoglobulin heavy chain enhancer. Mol Cancer 2007; 6:23. [PMID: 17386101 PMCID: PMC1852116 DOI: 10.1186/1476-4598-6-23] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Accepted: 03/26/2007] [Indexed: 01/27/2023] Open
Abstract
Bright/ARID3A is a nuclear matrix-associated transcription factor that stimulates immunoglobulin heavy chain (IgH) expression and Cyclin E1/E2F-dependent cell cycle progression. Bright positively activates IgH transcriptional initiation by binding to ATC-rich P sites within nuclear matrix attachment regions (MARs) flanking the IgH intronic enhancer (Eμ). Over-expression of Bright in cultured B cells was shown to correlate with DNase hypersensitivity of Eμ. We report here further efforts to analyze Bright-mediated Eμ enhancer activation within the physiological constraints of chromatin. A system was established in which VH promoter-driven in vitro transcription on chromatin- reconstituted templates was responsive to Eμ. Bright assisted in blocking the general repression caused by nucleosome assembly but was incapable of stimulating transcription from prebound nucleosome arrays. In vitro transcriptional derepression by Bright was enhanced on templates in which Eμ is flanked by MARs and was inhibited by competition with high affinity Bright binding (P2) sites. DNase hypersensitivity of chromatin-reconstituted Eμ was increased when prepackaged with B cell nuclear extract supplemented with Bright. These results identify Bright as a contributor to accessibility of the IgH enhancer.
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Affiliation(s)
- Danjuan Lin
- Section of Molecular Genetics and Microbiology and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Gregory C Ippolito
- Section of Molecular Genetics and Microbiology and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Rui-Ting Zong
- Section of Molecular Genetics and Microbiology and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - James Bryant
- Section of Molecular Genetics and Microbiology and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Janet Koslovsky
- Section of Molecular Genetics and Microbiology and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Philip Tucker
- Section of Molecular Genetics and Microbiology and Institute of Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
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Tanigawa Y, Yakura R, Komiya T. The bHLH transcription factor Tcf12 (ME1) mRNA is abundantly expressed in Paneth cells of mouse intestine. Gene Expr Patterns 2007; 7:709-13. [PMID: 17405739 DOI: 10.1016/j.modgep.2007.02.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 02/06/2007] [Accepted: 02/23/2007] [Indexed: 10/23/2022]
Abstract
Using a large-scale in situ hybridization screening system, we found that mRNA coding for ME1, a basic helix-loop-helix (bHLH) transcription factor, was abundantly expressed in Paneth cells of adult small intestinal crypts. Other functionally related E-protein mRNAs, ME2, and E2A, however, could not be detected in the cells. ME1 mRNA was first detected in the jejunum and ileum two weeks after birth when the number of Paneth cells starts to increase. ME1 is the first identified bHLH transcription factor expressed in the Paneth cells and may be used as a molecular marker and a key molecule for analyzing transcriptional regulation in the Paneth cell.
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Affiliation(s)
- Yoko Tanigawa
- Department of Biological Function, Graduate School of Science, Osaka City University, Sumiyoshi, Osaka, Japan
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40
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Lazorchak AS, Wojciechowski J, Dai M, Zhuang Y. E2A promotes the survival of precursor and mature B lymphocytes. THE JOURNAL OF IMMUNOLOGY 2006; 177:2495-504. [PMID: 16888011 PMCID: PMC2228329 DOI: 10.4049/jimmunol.177.4.2495] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The basic helix-loop-helix transcription factor E2A is an essential regulator of B lymphocyte lineage commitment and is required to activate the expression of numerous B lineage-specific genes. Studies involving ectopic expression of Id proteins, which inhibit E2A as well as other basic helix-loop-helix proteins such as HEB, suggest additional roles of E2A at later stages of B cell development. We use E2A-deficient and E2A and HEB double-deficient pre-B cell lines to directly assess the function of E2A and HEB in B cell development after lineage commitment. We show that, in contrast to the established role of E2A in lineage commitment, elimination of E2A and HEB in pre-B cell lines has only a modest negative impact on B lineage gene expression. However, E2A single and E2A and HEB double-deficient but not HEB single-deficient cell lines show dramatically enhanced apoptosis upon growth arrest. To address the possible role of E2A in the regulation of B cell survival in vivo, we crossed IFN-inducible Cre-transgenic mice to E2A conditional mice. Cre-mediated E2A deletion resulted in a block in bone marrow B cell development and a significant reduction in the proportion and total number of splenic B cells in these mice. We show that Cre-mediated deletion of E2A in adoptively transferred mature B cells results in the rapid depletion of the transferred population within 24 h of Cre induction. These results reveal that E2A is not required to maintain B cell fate but is essential in promoting pre-B and B cell survival.
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Affiliation(s)
| | | | | | - Yuan Zhuang
- Address correspondence and reprint requests to Dr. Yuan Zhuang, Department of Immunology, Duke University Medical Center, Box 3010, 328 Jones Building, Research Drive, Durham, NC 27710. E-mail address:
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41
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Lazorchak AS, Schlissel MS, Zhuang Y. E2A and IRF-4/Pip promote chromatin modification and transcription of the immunoglobulin kappa locus in pre-B cells. Mol Cell Biol 2006; 26:810-21. [PMID: 16428437 PMCID: PMC1347029 DOI: 10.1128/mcb.26.3.810-821.2006] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The immunoglobulin kappa light chain (Igkappa) locus is regulated in a lineage- and stage-specific manner during B-cell development. The highly restricted timing of V to J gene recombination at the pre-B-cell stage is under the control of two enhancers, the intronic enhancer (kappaEi) and the 3' enhancer (kappaE3'), flanking the constant exon. E2A transcription factors have been indicated to be directly involved in the regulation of Igkappa locus activation. In this study, we utilize E2A-deficient pre-B cells to directly investigate the mechanism of E2A-mediated Igkappa activation. We demonstrate that Igkappa germ line transcription is severely impaired and recombination is blocked in the absence of E2A. Reconstitution of E2A-/- pre-B cells with inducible human E2A (E47R) is sufficient to promote chromatin modification of Igkappa and rescue Igkappa germ line transcription and Jkappa gene recombinase accessibility. Furthermore, we show that increased E2A recruitment to kappaEi and kappaE3' correlates with activation of Igkappa in pre-B cells and that recruitment of E2A to kappaE3' is in part dependent on the transcription factor IRF-4. Inhibition of IRF-4 expression in pre-B cells leads to a significant reduction of Igkappa germ line transcription and enhancer acetylation. In the absence of E2A, increased IRF-4 expression is not sufficient to promote Igkappa enhancer chromatin modification or transcription, suggesting that the sequential involvement of IRF-4 and E2A is necessary for the activation of the Igkappa locus. Finally, we provide genetic evidence in the mouse that E2A gene dosage can influence the development of pre-B cells during the phase of Igkappa gene activation.
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Affiliation(s)
- Adam S Lazorchak
- Department of Immunology, Duke University Medical Center, Box 3010, 328 Jones Building, Research Drive, Durham, NC 27710, USA
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42
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Hagman J, Lukin K. Transcription factors drive B cell development. Curr Opin Immunol 2006; 18:127-34. [PMID: 16464566 DOI: 10.1016/j.coi.2006.01.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 01/25/2006] [Indexed: 11/25/2022]
Abstract
Transcription factors including PU.1, E2A and early B cell factor (EBF) are essential for the earliest stages of B lymphocyte development. Recent advances suggest that, although PU.1 initiates events leading to B lymphopoiesis, it might be dispensable at later stages of development. E2A proteins are also crucial for B cell lineage determination, as shown by the pluripotency of E2A-deficient progenitors. Both PU.1 and E2A are required for expression of EBF. EBF activates the early program of genes unique to B cells, including the lineage commitment factor Pax5. EBF also facilitates the function of Pax5 by mediating epigenetic changes necessary for the function of Pax5 at gene targets. Together, these proteins function in a hierarchy of factors that orchestrates B cell development.
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Affiliation(s)
- James Hagman
- Integrated Department of Immunology, National Jewish Medical and Research Center, 1400 Jackson Street, K516B, Denver, CO 80206, USA.
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43
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Allman D, Miller JP. B cell development and receptor diversity during aging. Curr Opin Immunol 2005; 17:463-7. [PMID: 16054808 DOI: 10.1016/j.coi.2005.07.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Accepted: 07/19/2005] [Indexed: 10/25/2022]
Abstract
Although it is clear that B cell genesis declines with age, the specifics of why this happens are largely unknown. Even less clear is how the age-related decline in B cell development might affect peripheral B cell function. Recent studies have investigated the impact of aging on both B cell genesis in the bone marrow and the resulting peripheral B cell repertoire. On the basis of these studies we propose a model in which the aging of very early B cell progenitors results in shifts in the peripheral B cell repertoire and, consequently, changes in mature B cell function.
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Affiliation(s)
- David Allman
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6082, USA.
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44
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Abstract
B cell genesis declines with age, but at what stage and why remains unclear. Previous studies attribute the decline in B cell production in aged mice to both environmental and cell-intrinsic defects that impact mid-to-late stream B cell precursors. However, mounting evidence suggests that the aging process may also negatively affect the earliest phases of B cell development. We review past studies on the B cells and aging question, discuss recent data suggesting that age-associated defects in B cell development reflect deficiencies in hematopoietic stem cell-proximal progenitor pools, and provide an integrative model that will hopefully facilitate further studies into this complex problem.
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Affiliation(s)
- Juli P Miller
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, 269 John Morgan Building, 36th and Hamilton Walk, Philadelphia, PA 19104, USA
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45
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Polli M, Dakic A, Light A, Wu L, Tarlinton DM, Nutt SL. The development of functional B lymphocytes in conditional PU.1 knock-out mice. Blood 2005; 106:2083-90. [PMID: 15933053 DOI: 10.1182/blood-2005-01-0283] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
An abundance of research has entrenched the view that the Ets domain containing transcription factor PU.1 is fundamental to the development and function of B lymphocytes. In this study, we have made use of a conditional PU.1 allele to test this notion. Complete deletion of PU.1 resulted in the loss of B cells and all other lineage-positive cells in the fetal liver and death between E18.5 and birth; however, specific deletion of PU.1 in the B lineage had no effect on B-cell development. Furthermore, deletion of PU.1 in B cells did not compromise their ability to establish and maintain an immune response. An increased level of apoptosis was observed in vitro upon B-cell receptor (BCR) cross-linking; however, this was partially rescued by interleukin-4 (IL-4). These findings suggest that PU.1 is not essential for the development of functional B lymphocytes beyond the pre-B stage. (Blood. 2005;106:2083-2090)
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Affiliation(s)
- Matthew Polli
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria, Australia 3050
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46
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Hagman J, Lukin K. Early B-cell factor ‘pioneers’ the way for B-cell development. Trends Immunol 2005; 26:455-61. [PMID: 16027038 DOI: 10.1016/j.it.2005.07.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 06/20/2005] [Accepted: 07/06/2005] [Indexed: 01/14/2023]
Abstract
Early B-cell factor (EBF) is a DNA-binding protein required for B-cell lymphopoiesis. The lack of EBF results in an early developmental blockade, including the lack of functional B cells and Igs. Recent studies have elucidated a central role for EBF in the specification of B-lineage cells. EBF directs progenitor cells to undergo B lymphopoiesis and activates transcription of B cell-specific genes in the absence of upstream regulators. How EBF mediates these effects has yet to be thoroughly explored, however, it initiates epigenetic modifications necessary for gene activation and the function of other transcriptional regulators, including Pax5. Together, these observations suggest a molecular basis for the role of EBF in the hierarchical network of factors that control B lymphopoiesis.
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Affiliation(s)
- James Hagman
- Integrated Department of Immunology, National Jewish Medical and Research Center, Denver, CO 80206, USA.
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Lazorchak A, Jones ME, Zhuang Y. New insights into E-protein function in lymphocyte development. Trends Immunol 2005; 26:334-8. [PMID: 15922950 DOI: 10.1016/j.it.2005.03.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 02/28/2005] [Accepted: 03/24/2005] [Indexed: 11/20/2022]
Abstract
Lymphocyte development has long served as an experimental paradigm, revealing fundamental mechanisms of gene regulation and cellular differentiation in mammals. The study of E-protein-mediated transcriptional regulation in lymphocyte development provides a means to address these mechanistic issues. Both genetic and biochemical studies have defined many important regulatory events during lymphocyte development that are mediated by E-proteins. The E2A gene, one of the three known E-protein genes in mammals, has a particularly important role in B-lymphocyte development. Major progress has been made in recent years towards understanding the physiological targets of E2A during B-lymphocyte development. Most notably, new insights have been gained regarding the role of E2A in controlling lineage commitment and V(D)J recombination. This Review focuses primarily on E2A-mediated gene regulation during B-lymphocyte development.
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Affiliation(s)
- Adam Lazorchak
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
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Abstract
B-cell genesis in the bone marrow declines with advancing age. In this review, we discuss our current understanding of why B-cell production rates decline with age with a special emphasis on why age-related factors might target very early lymphoid precursors. We consider the impact of aging on cytokine responsiveness and how current models for lineage relationships for very early B- and T-cell precursors might influence interpretations of experiments addressing age-associated declines in B- and T-cell differentiation. This discussion centers on the notion that aging affects events associated with the process by which hematopoietic stem cells are guided toward the B-cell pathway. Finally, we present a model in which the age-associated loss of early B-cell precursors is linked to suboptimal function of key transcriptional regulators of very early B-cell development.
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Affiliation(s)
- David Allman
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, 19104, USA.
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Fang H, Sodja C, Chartier J, Desbois A, Lei J, Walker PR, Sikorska M. Identification of a functional CRE in the promoter of Fukuyama congenital muscular dystrophy gene fukutin. ACTA ACUST UNITED AC 2005; 136:1-11. [PMID: 15893581 DOI: 10.1016/j.molbrainres.2004.12.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Revised: 12/15/2004] [Accepted: 12/20/2004] [Indexed: 01/16/2023]
Abstract
We isolated a fragment of the fukutin gene promoter from differentiated human NT2 cells using chromatin immunoprecipitation technique with an anti-CREB antibody. This fragment contained a CRE-like sequence and here we describe its functional validation. The results showed that the element was functional in vitro and in vivo and that CREB in neurons was involved in the transcriptional regulation of the fukutin gene. Moreover, its expression in neurons was regulated by cAMP and calcium ions, known triggers of CREB phosphorylation. To our knowledge, this is the first report on the regulation of fukutin gene by transcription factor CREB in response to the signals generated by synaptic activity. The true biological function of fukutin, the gene responsible for Fukuyama-type congenital muscular dystrophy and mental retardation, is at present not known. However, it has been suggested that it might possess glycosyltransferase activity and its intracellular localization within the Golgi structures is consistent with this function. As such, fukutin might play a significant role in post-translational modification of synaptic proteins in neuronal cells.
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Affiliation(s)
- Hung Fang
- Neurogenesis and Brain Repair Group, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A 0R6.
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Matuszewski L, Persigehl T, Wall A, Schwindt W, Tombach B, Fobker M, Poremba C, Ebert W, Heindel W, Bremer C. Cell Tagging with Clinically Approved Iron Oxides: Feasibility and Effect of Lipofection, Particle Size, and Surface Coating on Labeling Efficiency. Radiology 2005; 235:155-61. [PMID: 15749976 DOI: 10.1148/radiol.2351040094] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the effect of lipofection, particle size, and surface coating on labeling efficiency of mammalian cells with superparamagnetic iron oxides (SPIOs). MATERIALS AND METHODS Institutional Review Board approval was not required. Different human cell lines (lung and breast cancer, fibrosarcoma, leukocytes) were tagged by using carboxydextran-coated SPIOs of various hydrodynamic diameters (17-65 nm) and a dextran-coated iron oxide (150 nm). Cells were incubated with increasing concentrations of iron (0.01-1.00 mg of iron [Fe] per milliliter), including or excluding a transfection medium (TM). Cellular iron uptake was analyzed qualitatively at light and electron microscopy and was quantified at atomic emission spectroscopy. Cell visibility was assessed with gradient- and spin-echo magnetic resonance (MR) imaging. Effects of iron concentration in the medium and of lipofection on cellular SPIO uptake were analyzed with analysis of variance and two-tailed Student t test, respectively. RESULTS Iron oxide uptake increased in a dose-dependent manner with higher iron concentrations in the medium. The TM significantly increased the iron load of cells (up to 2.6-fold, P < .05). For carboxydextran-coated SPIOs, larger particle size resulted in improved cellular uptake (65 nm, 4.37 microg +/- 0.08 Fe per 100 000 cells; 17 nm, 2.14 microg +/- 0.06 Fe per 100 000 cells; P < .05). Despite larger particle size, dextran-coated iron oxides did not differ from large carboxydextran-coated particles (150 nm, 3.81 microg +/- 0.46 Fe per 100 000 cells; 65 nm, 4.37 microg +/- 0.08 Fe per 100 000 cells; P > .05). As few as 10 000 cells could be detected with clinically available MR techniques by using this approach. CONCLUSION Lipofection-based cell tagging is a simple method for efficient cell labeling with clinically approved iron oxide-based contrast agents. Large particle size and carboxydextran coating are preferable for cell tagging with endocytosis- and lipofection-based methods.
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Affiliation(s)
- Lars Matuszewski
- Department of Clinical Radiology, University Hospital Muenster, Albert-Schweitzer-Strasse 33, D-48129 Muenster, Germany
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