1
|
Abstract
DLK1 is a maternally imprinted, paternally expressed gene coding for the transmembrane protein Delta-like homologue 1 (DLK1), a non-canonical NOTCH ligand with well-described roles during development, and tumor-supportive functions in several aggressive cancer forms. Here, we review the many functions of DLK1 as a regulator of stem cell pools and tissue differentiation in tissues such as brain, muscle, and liver. Furthermore, we review recent evidence supporting roles for DLK1 in the maintenance of aggressive stem cell characteristics of tumor cells, specifically focusing on central nervous system tumors, neuroblastoma, and hepatocellular carcinoma. We discuss NOTCH -dependent as well as NOTCH-independent functions of DLK1, and focus particularly on the complex pattern of DLK1 expression and cleavage that is finely regulated from a spatial and temporal perspective. Progress in recent years suggest differential functions of extracellular, soluble DLK1 as a paracrine stem cell niche-secreted factor, and has revealed a role for the intracellular domain of DLK1 in cell signaling and tumor stemness. A better understanding of DLK1 regulation and signaling may enable therapeutic targeting of cancer stemness by interfering with DLK1 release and/or intracellular signaling.
Collapse
Affiliation(s)
- Elisa Stellaria Grassi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Alexander Pietras
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, Lund, Sweden
| |
Collapse
|
2
|
Dong Y, Guo H, Wang D, Tu R, Qing G, Liu H. Genome-Wide Analysis Identifies Rag1 and Rag2 as Novel Notch1 Transcriptional Targets in Thymocytes. Front Cell Dev Biol 2021; 9:703338. [PMID: 34322489 PMCID: PMC8311795 DOI: 10.3389/fcell.2021.703338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/15/2021] [Indexed: 12/04/2022] Open
Abstract
Recombination activating genes 1 (Rag1) and Rag2 are expressed in immature lymphocytes and essential for generating the vast repertoire of antigen receptors. Yet, the mechanisms governing the transcription of Rag1 and Rag2 remain to be fully determined, particularly in thymocytes. Combining cDNA microarray and ChIP-seq analysis, we identify Rag1 and Rag2 as novel Notch1 transcriptional targets in acute T-cell lymphoblastic leukemia (T-ALL) cells. We further demonstrate that Notch1 transcriptional complexes directly bind the Rag1 and Rag2 locus in not only T-ALL but also primary double negative (DN) T-cell progenitors. Specifically, dimeric Notch1 transcriptional complexes activate Rag1 and Rag2 through a novel cis-element bearing a sequence-paired site (SPS). In T-ALL and DN cells, dimerization-defective Notch1 causes compromised Rag1 and Rag2 expression; conversely, dimerization-competent Notch1 achieves optimal upregulation of both. Collectively, these results reveal Notch1 dimerization-mediated transcription as one of the mechanisms for activating Rag1 and Rag2 expression in both primary and transformed thymocytes. Our data suggest a new role of Notch1 dimerization in compelling efficient TCRβ rearrangements in DN progenitors during T-cell development.
Collapse
Affiliation(s)
- Yang Dong
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Hao Guo
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Donghai Wang
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Rongfu Tu
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Guoliang Qing
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Hudan Liu
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, China.,Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| |
Collapse
|
3
|
Nitta T, Ota A, Iguchi T, Muro R, Takayanagi H. The fibroblast: An emerging key player in thymic T cell selection. Immunol Rev 2021; 302:68-85. [PMID: 34096078 PMCID: PMC8362222 DOI: 10.1111/imr.12985] [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: 02/02/2021] [Revised: 05/04/2021] [Accepted: 05/08/2021] [Indexed: 02/06/2023]
Abstract
Fibroblasts have recently attracted attention as a key stromal component that controls the immune responses in lymphoid tissues. The thymus has a unique microenvironment comprised of a variety of stromal cells, including fibroblasts and thymic epithelial cells (TECs), the latter of which is known to be important for T cell development because of their ability to express self‐antigens. Thymic fibroblasts contribute to thymus organogenesis during embryogenesis and form the capsule and medullary reticular network in the adult thymus. However, the immunological significance of thymic fibroblasts has thus far only been poorly elucidated. In this review, we will summarize the current views on the development and functions of thymic fibroblasts as revealed by new technologies such as multicolor flow cytometry and single cell–based transcriptome profiling. Furthermore, the recently discovered role of medullary fibroblasts in the establishment of T cell tolerance by producing a unique set of self‐antigens will be highlighted.
Collapse
Affiliation(s)
- Takeshi Nitta
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ayami Ota
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Takahiro Iguchi
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ryunosuke Muro
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Takayanagi
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
4
|
Rodríguez-Cano MM, González-Gómez MJ, Sánchez-Solana B, Monsalve EM, Díaz-Guerra MJM, Laborda J, Nueda ML, Baladrón V. NOTCH Receptors and DLK Proteins Enhance Brown Adipogenesis in Mesenchymal C3H10T1/2 Cells. Cells 2020; 9:cells9092032. [PMID: 32899774 PMCID: PMC7565505 DOI: 10.3390/cells9092032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/27/2020] [Accepted: 09/03/2020] [Indexed: 12/26/2022] Open
Abstract
The NOTCH family of receptors and ligands is involved in numerous cell differentiation processes, including adipogenesis. We recently showed that overexpression of each of the four NOTCH receptors in 3T3-L1 preadipocytes enhances adipogenesis and modulates the acquisition of the mature adipocyte phenotype. We also revealed that DLK proteins modulate the adipogenesis of 3T3-L1 preadipocytes and mesenchymal C3H10T1/2 cells in an opposite way, despite their function as non-canonical inhibitory ligands of NOTCH receptors. In this work, we used multipotent C3H10T1/2 cells as an adipogenic model. We used standard adipogenic procedures and analyzed different parameters by using quantitative-polymerase chain reaction (qPCR), quantitative reverse transcription-polymerase chain reaction (qRT-PCR), luciferase, Western blot, and metabolic assays. We revealed that C3H10T1/2 multipotent cells show higher levels of NOTCH receptors expression and activity and lower Dlk gene expression levels than 3T3-L1 preadipocytes. We found that the overexpression of NOTCH receptors enhanced C3H10T1/2 adipogenesis levels, and the overexpression of NOTCH receptors and DLK (DELTA-like homolog) proteins modulated the conversion of cells towards a brown-like adipocyte phenotype. These and our prior results with 3T3-L1 preadipocytes strengthen the idea that, depending on the cellular context, a precise and highly regulated level of global NOTCH signaling is necessary to allow adipogenesis and determine the mature adipocyte phenotype.
Collapse
Affiliation(s)
- María-Milagros Rodríguez-Cano
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Farmacia/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (M.-M.R.-C.); (M.-J.G.-G.)
| | - María-Julia González-Gómez
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Farmacia/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (M.-M.R.-C.); (M.-J.G.-G.)
| | - Beatriz Sánchez-Solana
- National Institutes of Health, Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA;
| | - Eva-María Monsalve
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Medicina de Albacete/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (E.-M.M.); (M.-J.M.D.-G.)
| | - María-José M. Díaz-Guerra
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Medicina de Albacete/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (E.-M.M.); (M.-J.M.D.-G.)
| | - Jorge Laborda
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Farmacia/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (M.-M.R.-C.); (M.-J.G.-G.)
- Correspondence: (J.L.); (M.-L.N.); (V.B.); Tel.: +34-967-599-200 (ext. 2926) (V.B.); Fax: +34-967-599-327 (V.B.)
| | - María-Luisa Nueda
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Farmacia/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (M.-M.R.-C.); (M.-J.G.-G.)
- Correspondence: (J.L.); (M.-L.N.); (V.B.); Tel.: +34-967-599-200 (ext. 2926) (V.B.); Fax: +34-967-599-327 (V.B.)
| | - Victoriano Baladrón
- Departamento de Química Inorgánica, Laboratorio de Bioquímica y Biología Molecular, Facultad de Medicina de Albacete/CRIB/Unidad de Biomedicina, Orgánica y Bioquímica, Universidad de Castilla-La Mancha/CSIC, C/Almansa 14, 02008 Albacete, Spain; (E.-M.M.); (M.-J.M.D.-G.)
- Correspondence: (J.L.); (M.-L.N.); (V.B.); Tel.: +34-967-599-200 (ext. 2926) (V.B.); Fax: +34-967-599-327 (V.B.)
| |
Collapse
|
5
|
Traustadóttir GÁ, Lagoni LV, Ankerstjerne LBS, Bisgaard HC, Jensen CH, Andersen DC. The imprinted gene Delta like non-canonical Notch ligand 1 (Dlk1) is conserved in mammals, and serves a growth modulatory role during tissue development and regeneration through Notch dependent and independent mechanisms. Cytokine Growth Factor Rev 2019; 46:17-27. [DOI: 10.1016/j.cytogfr.2019.03.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 03/21/2019] [Accepted: 03/21/2019] [Indexed: 12/22/2022]
|
6
|
Briana DD, Papathanasiou AE, Gavrili S, Georgantzi S, Marmarinos A, Christou C, Voulgaris K, Gourgiotis D, Malamitsi-Puchner A. Preadipocyte factor-1 in maternal, umbilical cord serum and breast milk: The impact of fetal growth. Cytokine 2019; 114:143-148. [PMID: 30459083 DOI: 10.1016/j.cyto.2018.11.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 11/07/2018] [Accepted: 11/12/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND/OBJECTIVE To study the concentrations of preadipocyte factor-1 (Pref-1) -an inhibitor of adipocyte differentiation, implicated in adipose tissue metabolism, late metabolic disorders and fetal growth- in maternal and umbilical cord serum, as well as maternal milk and correlate above concentrations with intrauterine growth and other perinatal parameters. MATERIAL AND METHODS Pref-1 concentrations were determined by ELISA in antepartum maternal and umbilical cord serum, as well as day 3 to 4 postpartum breast milk, deriving from 80 women, who delivered 40 appropriate (AGA), 20 large for gestational age (LGA) and 20 intrauterine growth restricted (IUGR) neonates, classified by the use of customized birth-weight standards adjusted for significant determinants of fetal growth. RESULTS Umbilical cord serum Pref-1 concentrations were significantly higher than antepartum maternal ones (p < 0.001), while breast milk concentrations were the lowest (p < 0.001 concerning umbilical serum, p < 0.001 concerning maternal serum). Umbilical cord serum Pref-1 concentrations were significantly lower in the LGA group than in the AGA one (p = 0.044). Breast milk and maternal serum Pref-1 concentrations did not differ between the three intrauterine growth groups. Maternal serum and breast milk Pref-1 concentrations did not correlate with maternal age, body mass index before and after gestation, birth weight, body length, and customized centile. A positive weak correlation was recorded between maternal serum and milk Pref-1 concentrations (r = 0.238, p = 0.034). CONCLUSIONS Pref-1 concentrations in umbilical cord serum are higher than in antepartum maternal serum, probably pointing to its fetal origin and role in intrauterine growth. Breast milk concentrations, being extremely low, and possibly implying infant protection from metabolic disorders, positively correlate with maternal serum ones, conceivably suggesting a transfer of the substance from the circulation to the breast. Umbilical cord serum Pref-1 concentrations were lower in LGA fetuses/neonates, as compared to respective AGA ones.
Collapse
Affiliation(s)
- Despina D Briana
- National and Kapodistrian University of Athens, Medical School, Athens, Greece
| | | | - Stavroula Gavrili
- Neonatal Intensive Care Unit, "Alexandra" University and State Maternity Hospital, Athens, Greece
| | - Sophia Georgantzi
- Neonatal Intensive Care Unit, "Alexandra" University and State Maternity Hospital, Athens, Greece
| | - Antonios Marmarinos
- Laboratory of Clinical Biochemistry-Molecular Diagnostics, 2(nd) Department of Pediatrics, National and Kapodistrian University of Athens, Athens, Greece
| | | | | | - Dimitrios Gourgiotis
- Laboratory of Clinical Biochemistry-Molecular Diagnostics, 2(nd) Department of Pediatrics, National and Kapodistrian University of Athens, Athens, Greece
| | | |
Collapse
|
7
|
|
8
|
Mitchell M, Strick R, Strissel PL, Dittrich R, McPherson NO, Lane M, Pliushch G, Potabattula R, Haaf T, El Hajj N. Gene expression and epigenetic aberrations in F1-placentas fathered by obese males. Mol Reprod Dev 2017; 84:316-328. [PMID: 28186371 DOI: 10.1002/mrd.22784] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 02/06/2017] [Indexed: 12/17/2022]
Abstract
Gene expression and/or epigenetic deregulation may have consequences for sperm and blastocysts, as well as for the placenta, together potentially contributing to problems observed in offspring. We previously demonstrated specific perturbations of fertilization, blastocyst formation, implantation, as well as aberrant glucose metabolism and adiposity in offspring using a mouse model of paternal obesity. The current investigation analyzed gene expression and methylation of specific CpG residues in F1 placentas of pregnancies fathered by obese and normal-weight male mice, using real-time PCR and bisulfite pyrosequencing. Our aim was to determine if paternal obesity deregulated placental gene expression and DNA methylation when compared to normal-weight males. Gene methylation of sperm DNA was analyzed and compared to placentas to address epigenetic transmission. Of the 10 paternally expressed genes (Pegs), 11 genes important for development and transport of nutrients, and the long-terminal repeat Intracisternal A particle (IAP) elements, derived from a member of the class II endogenous retroviral gene family, we observed a significant effect of paternal diet-induced obesity on deregulated expression of Peg3, Peg9, Peg10, and the nutrient transporter gene Slc38a2, and aberrant DNA methylation of the Peg9 promoter in F1 placental tissue. Epigenetic changes in Peg9 were also found in sperm from obese fathers. We therefore propose that paternal obesity renders changes in gene expression and/or methylation throughout the placental genome, which could contribute to the reproductive problems related to fertility and to the metabolic, long-term health impact on offspring.
Collapse
Affiliation(s)
- Megan Mitchell
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Laboratory for Molecular Medicine, Universitaetsstrasse, Erlangen, Germany.,School of Paediatrics and Reproductive Health, The Robinson Institute, University of Adelaide, South Australia, Australia
| | - Reiner Strick
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Laboratory for Molecular Medicine, Universitaetsstrasse, Erlangen, Germany
| | - Pamela L Strissel
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Laboratory for Molecular Medicine, Universitaetsstrasse, Erlangen, Germany
| | - Ralf Dittrich
- Department of Obstetrics and Gynaecology, Erlangen University Hospital, Laboratory for Molecular Medicine, Universitaetsstrasse, Erlangen, Germany
| | - Nicole O McPherson
- School of Paediatrics and Reproductive Health, The Robinson Institute, University of Adelaide, South Australia, Australia
| | - Michelle Lane
- School of Paediatrics and Reproductive Health, The Robinson Institute, University of Adelaide, South Australia, Australia.,Repromed, Dulwich, Adelaide, South Australia
| | - Galyna Pliushch
- Institute of Human Genetics, Julius Maximillians University, Biozentrum, Am Hubland, Würzburg, Germany
| | - Ramya Potabattula
- Institute of Human Genetics, Julius Maximillians University, Biozentrum, Am Hubland, Würzburg, Germany
| | - Thomas Haaf
- Institute of Human Genetics, Julius Maximillians University, Biozentrum, Am Hubland, Würzburg, Germany
| | - Nady El Hajj
- Institute of Human Genetics, Julius Maximillians University, Biozentrum, Am Hubland, Würzburg, Germany
| |
Collapse
|
9
|
Lee D, Yoon SH, Lee HJ, Jo KW, Park BC, Kim IS, Choi Y, Lim JC, Park YW. Human soluble delta-like 1 homolog exerts antitumor effects in vitro and in vivo. Biochem Biophys Res Commun 2016; 475:209-15. [PMID: 27191393 DOI: 10.1016/j.bbrc.2016.05.076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 05/14/2016] [Indexed: 10/21/2022]
Abstract
Proteolysis of delta-like 1 homolog (DLK1), a cell-surface transmembrane protein, produces an active soluble form of DLK1 (sDLK1). Both membrane-bound DLK1 and sDLK1 modulate multiple developmental processes including adipogenesis, osteogenesis, chondrogenesis and myogenesis. However, cancer-related functions of DLK1 have not yet been established. We thus evaluated the roles of extracellular sDLK1, comprising six EGF-like domains and juxtamembrane regions, in human pancreatic cancer MIA PaCa-2 cells in vitro and in vivo. We observed that sDLK1 exerted antitumor effects not only in cancer cell migration and anchorage-independent cell growth but also in in vivo tumor growth.
Collapse
Affiliation(s)
- Donghee Lee
- Aging Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, 34141, Republic of Korea
| | - Sun Ha Yoon
- Aging Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, 34141, Republic of Korea
| | - Hyun Ju Lee
- Aging Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, 34141, Republic of Korea
| | - Ki Won Jo
- Aging Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, 34141, Republic of Korea
| | - Bum-Chan Park
- Aging Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, 34141, Republic of Korea
| | - In Seop Kim
- Department of Biological Sciences and Biotechnology, Hannam University, Daejeon, 34054, Republic of Korea
| | - Yunseon Choi
- Department of Biological Sciences and Biotechnology, Hannam University, Daejeon, 34054, Republic of Korea
| | - Jung Chae Lim
- ANRT, Inc., PAI CHAI University Industry-Academic Cooperation Foundation Building, Daejeon, 34015, Republic of Korea.
| | - Young Woo Park
- Aging Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, 34141, Republic of Korea.
| |
Collapse
|
10
|
HES1 in immunity and cancer. Cytokine Growth Factor Rev 2016; 30:113-7. [PMID: 27066918 DOI: 10.1016/j.cytogfr.2016.03.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 03/18/2016] [Accepted: 03/18/2016] [Indexed: 01/06/2023]
Abstract
Hairy and enhancer of split homolog-1 (HES1) is a part of an extensive family of basic helix-loop-helix (bHLH) proteins and plays a crucial role in the control and regulation of cell cycle, proliferation, cell differentiation, survival and apoptosis in neuronal, endocrine, T-lymphocyte progenitors as well as various cancers. HES1 is a transcription factor which is regulated by the NOTCH, Hedgehog and Wnt signalling pathways. Aberrant expression of these pathways is a common feature of cancerous cells. There appears to be a fine and complicated crosstalk at the molecular level between the various signalling pathways and HES1, which contributes to its effects on the immune response and cancers such as leukaemia. Several mechanisms have been proposed, including an enhanced invasiveness and metastasis by inducing epithelial mesenchymal transition (EMT), in addition to its strict requirement for tumour cell survival. In this review, we summarize the current biology and molecular mechanisms as well as its use as a clinical target in cancer therapeutics.
Collapse
|
11
|
Traustadóttir GÁ, Jensen CH, Thomassen M, Beck HC, Mortensen SB, Laborda J, Baladrón V, Sheikh SP, Andersen DC. Evidence of non-canonical NOTCH signaling: Delta-like 1 homolog (DLK1) directly interacts with the NOTCH1 receptor in mammals. Cell Signal 2016; 28:246-54. [PMID: 26791579 DOI: 10.1016/j.cellsig.2016.01.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/08/2016] [Accepted: 01/08/2016] [Indexed: 12/21/2022]
Abstract
Canonical NOTCH signaling, known to be essential for tissue development, requires the Delta-Serrate-LAG2 (DSL) domain for NOTCH to interact with its ligand. However, despite lacking DSL, Delta-like 1 homolog (DLK1), a protein that plays a significant role in mammalian development, has been suggested to interact with NOTCH1 and act as an antagonist. This non-canonical interaction is, however controversial, and evidence for a direct interaction, still lacking in mammals. In this study, we elucidated the putative DLK1-NOTCH1 interaction in a mammalian context. Taking a global approach and using Dlk1(+/+) and Dlk1(-/-) mouse tissues at E16.5, we demonstrated that several NOTCH signaling pathways indeed are affected by DLK1 during tissue development, and this was supported by a lower activation of NOTCH1 protein in Dlk1(+/+) embryos. Likewise, but using a distinct Dlk1-manipulated (siRNA) setup in a mammalian cell line, NOTCH signaling was substantially inhibited by DLK1. Using a mammalian two-hybrid system, we firmly established that the effect of DLK1 on NOTCH signaling was due to a direct interaction between DLK1 and NOTCH1. By careful dissection of this mechanism, we found this interaction to occur between EGF domains 5 and 6 of DLK1 and EGF domains 10-15 of NOTCH1. Thus, our data provide the first evidence for a direct interaction between DLK1 and NOTCH1 in mammals, and substantiate that non-canonical NOTCH ligands exist, adding to the complexity of NOTCH signaling.
Collapse
Affiliation(s)
- Gunnhildur Ásta Traustadóttir
- Laboratory of Molecular and Cellular Cardiology, Dep. of Clinical Biochemistry and Pharmacology, Odense University Hospital (OUH), Winsloewparken 21 3rd, 5000 Odense C, Denmark; Cardiovascular and Renal Research (University of Southern Denmark), OUH, Denmark
| | - Charlotte H Jensen
- Laboratory of Molecular and Cellular Cardiology, Dep. of Clinical Biochemistry and Pharmacology, Odense University Hospital (OUH), Winsloewparken 21 3rd, 5000 Odense C, Denmark; The Danish Centre for Regenerative Medicine (danishcrm@com), OUH, Denmark
| | - Mads Thomassen
- Dep. of Clinical Genetics (OUH), OUH, Denmark; Clinical Institute (University of Southern Denmark), OUH, Denmark
| | - Hans Christian Beck
- Clinical Institute (University of Southern Denmark), OUH, Denmark; Dep. of Clinical Biochemistry and Pharmacology (OUH), OUH, Denmark
| | - Sussi B Mortensen
- Laboratory of Molecular and Cellular Cardiology, Dep. of Clinical Biochemistry and Pharmacology, Odense University Hospital (OUH), Winsloewparken 21 3rd, 5000 Odense C, Denmark; Dep. of Clinical Immunology (OUH), Denmark
| | - Jorge Laborda
- Department of Inorganic and Organic Chemistry and Biochemistry, Medical School, Regional Center for Biomedical Research, University of Castilla-La Mancha, Albacete, Spain
| | - Victoriano Baladrón
- Department of Inorganic and Organic Chemistry and Biochemistry, Medical School, Regional Center for Biomedical Research, University of Castilla-La Mancha, Albacete, Spain
| | - Søren P Sheikh
- Laboratory of Molecular and Cellular Cardiology, Dep. of Clinical Biochemistry and Pharmacology, Odense University Hospital (OUH), Winsloewparken 21 3rd, 5000 Odense C, Denmark; Cardiovascular and Renal Research (University of Southern Denmark), OUH, Denmark; The Danish Centre for Regenerative Medicine (danishcrm@com), OUH, Denmark
| | - Ditte C Andersen
- Laboratory of Molecular and Cellular Cardiology, Dep. of Clinical Biochemistry and Pharmacology, Odense University Hospital (OUH), Winsloewparken 21 3rd, 5000 Odense C, Denmark; Clinical Institute (University of Southern Denmark), OUH, Denmark; The Danish Centre for Regenerative Medicine (danishcrm@com), OUH, Denmark.
| |
Collapse
|
12
|
Im E, Kim H, Kim J, Lee H, Yang H. Tributyltin acetate-induced immunotoxicity is related to inhibition of T cell development in the mouse thymus. Mol Cell Toxicol 2015. [DOI: 10.1007/s13273-015-0022-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
13
|
Kilian TM, Beck-Sickinger AG. Recombinant expression and characterization of biologically active protein delta homolog 1. Protein Expr Purif 2015; 110:72-8. [DOI: 10.1016/j.pep.2015.02.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 02/07/2015] [Accepted: 02/09/2015] [Indexed: 10/24/2022]
|
14
|
Wang Y, Lee K, Moon YS, Ahmadian M, Kim KH, Roder K, Kang C, Sul HS. Overexpression of Pref-1 in pancreatic islet β-cells in mice causes hyperinsulinemia with increased islet mass and insulin secretion. Biochem Biophys Res Commun 2015; 461:630-5. [PMID: 25918019 DOI: 10.1016/j.bbrc.2015.04.078] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Accepted: 04/09/2015] [Indexed: 11/26/2022]
Abstract
Preadipocyte factor-1 (Pref-1) is made as a transmembrane protein containing EGF-repeats at the extracellular domain that can be cleaved to generate a biologically active soluble form. Pref-1 is found in islet β-cells and its level has been reported to increase in neonatal rat islets upon growth hormone treatment. We found here that Pref-1 can promote growth of pancreatic tumor derived AR42J cells. To examine Pref-1 function in pancreatic islets in vivo, we generated transgenic mouse lines overexpressing the Pref-1/hFc in islet β-cells using rat insulin II promoter (RIP). These transgenic mice exhibit an increase in islet mass with higher proportion of larger islets in pancreas compared to wild-type littermates. This is in contrast to pancreas from Pref-1 null mice that show higher proportion of smaller islets. Insulin expression and insulin secretion from pancreatic islets from RIP-Pref-1/hFc transgenic mice are increased also. Thus, RIP-Pref-1/hFc transgenic mice show normal glucose levels but with higher plasma insulin levels in both fasting and fed conditions. These mice show improved glucose tolerance. Taken together, we conclude Pref-1 as a positive regulator of islet β-cells and insulin production.
Collapse
Affiliation(s)
- Yuhui Wang
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Kichoon Lee
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Yang Soo Moon
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Maryam Ahmadian
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Kee-Hong Kim
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Karim Roder
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Chulho Kang
- Department of Molecular Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Hei Sook Sul
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA.
| |
Collapse
|
15
|
Kang JA, Kim WS, Park SG. Notch1 is an important mediator for enhancing of B-cell activation and antibody secretion by Notch ligand. Immunology 2015; 143:550-9. [PMID: 24913005 DOI: 10.1111/imm.12333] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 06/03/2014] [Accepted: 06/04/2014] [Indexed: 12/27/2022] Open
Abstract
The roles of Notch1 and Notch2 in T-cell function have been well studied, but the functional roles of Notch in B cells have not been extensively investigated, except for Notch2 involvement in peripheral marginal zone B-cell differentiation. This study examined the roles of Notch1 in murine primary B cells. During B-cell activation by B-cell receptor ligation, Notch1 was up-regulated while Notch2 was not. In addition, Notch1 up-regulation itself did not contribute to the further activation of B cells, but the Notch ligand was important for Notch1-mediated further B-cell activation. Moreover, Notch1 deficiency significantly decreased B-cell activation and antibody secretion under the presence of Notch ligand. These data suggest that Notch1 is an important mediator for enhancing B-cell activation and antibody secretion by Notch ligand.
Collapse
Affiliation(s)
- Jung-Ah Kang
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea; Bio Imaging Research Centre and Immune Synapse Research Centre, Gwangju Institute of Science and Technology (GIST), Gwangju, Korea
| | | | | |
Collapse
|
16
|
Delta-Like Homologue 1 and Its Role in the Bone Marrow Niche and Hematologic Malignancies. CLINICAL LYMPHOMA MYELOMA & LEUKEMIA 2014; 14:451-5. [DOI: 10.1016/j.clml.2014.06.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/08/2014] [Accepted: 06/17/2014] [Indexed: 01/08/2023]
|
17
|
Benetatos L, Vartholomatos G, Hatzimichael E. DLK1-DIO3 imprinted cluster in induced pluripotency: landscape in the mist. Cell Mol Life Sci 2014; 71:4421-30. [PMID: 25098353 PMCID: PMC11113449 DOI: 10.1007/s00018-014-1698-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 07/29/2014] [Accepted: 07/31/2014] [Indexed: 12/20/2022]
Abstract
DLK1-DIO3 represents an imprinted cluster which genes are involved in physiological cell biology as early as the stem cell level and in the pathogenesis of several diseases. Transcription factor-mediated induced pluripotent cells (iPSCs) are considered an unlimited source of patient-specific hematopoietic stem cells for clinical application in patient-tailored regenerative medicine. However, to date there is no marker established able to distinguish embryonic stem cell-equivalent iPSCs or safe human iPSCs. Recent findings suggest that the DLK1-DIO3 locus possesses the potential to represent such a marker but there are also contradictory data. This review aims to report the current data on the topic describing both sides of the coin.
Collapse
Affiliation(s)
- Leonidas Benetatos
- Blood Bank, Selefkeias 2, Preveza General Hospital, 48100, Preveza, Greece,
| | | | | |
Collapse
|
18
|
Tuncel J, Haag S, Yau ACY, Norin U, Baud A, Lönnblom E, Maratou K, Ytterberg AJ, Ekman D, Thordardottir S, Johannesson M, Gillett A, Stridh P, Jagodic M, Olsson T, Fernández-Teruel A, Zubarev RA, Mott R, Aitman TJ, Flint J, Holmdahl R. Natural polymorphisms in Tap2 influence negative selection and CD4∶CD8 lineage commitment in the rat. PLoS Genet 2014; 10:e1004151. [PMID: 24586191 PMCID: PMC3930506 DOI: 10.1371/journal.pgen.1004151] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 12/16/2013] [Indexed: 12/17/2022] Open
Abstract
Genetic variation in the major histocompatibility complex (MHC) affects CD4∶CD8 lineage commitment and MHC expression. However, the contribution of specific genes in this gene-dense region has not yet been resolved. Nor has it been established whether the same genes regulate MHC expression and T cell selection. Here, we assessed the impact of natural genetic variation on MHC expression and CD4∶CD8 lineage commitment using two genetic models in the rat. First, we mapped Quantitative Trait Loci (QTLs) associated with variation in MHC class I and II protein expression and the CD4∶CD8 T cell ratio in outbred Heterogeneous Stock rats. We identified 10 QTLs across the genome and found that QTLs for the individual traits colocalized within a region spanning the MHC. To identify the genes underlying these overlapping QTLs, we generated a large panel of MHC-recombinant congenic strains, and refined the QTLs to two adjacent intervals of ∼0.25 Mb in the MHC-I and II regions, respectively. An interaction between these intervals affected MHC class I expression as well as negative selection and lineage commitment of CD8 single-positive (SP) thymocytes. We mapped this effect to the transporter associated with antigen processing 2 (Tap2) in the MHC-II region and the classical MHC class I gene(s) (RT1-A) in the MHC-I region. This interaction was revealed by a recombination between RT1-A and Tap2, which occurred in 0.2% of the rats. Variants of Tap2 have previously been shown to influence the antigenicity of MHC class I molecules by altering the MHC class I ligandome. Our results show that a restricted peptide repertoire on MHC class I molecules leads to reduced negative selection of CD8SP cells. To our knowledge, this is the first study showing how a recombination between natural alleles of genes in the MHC influences lineage commitment of T cells. Peptides from degraded cytoplasmic proteins are transported via TAP into the endoplasmic reticulum for loading onto MHC class I molecules. TAP is encoded by Tap1 and Tap2, which in rodents are located close to the MHC class I genes. In the rat, genetic variation in Tap2 gives rise to two different transporters: a promiscuous A variant (TAP-A) and a more restrictive B variant (TAP-B). It has been proposed that the class I molecule in the DA rat (RT1-Aa) has co-evolved with TAP-A and it has been shown that RT1-Aa antigenicity is changed when co-expressed with TAP-B. To study the contribution of different allelic combinations of RT1-A and Tap2 to the variation in MHC expression and T cell selection, we generated DA rats with either congenic or background alleles in the RT1-A and Tap2 loci. We found increased numbers of mature CD8SP cells in the thymus of rats which co-expressed RT1-Aa and TAP-B. This increase of CD8 cells could be explained by reduced negative selection, but did not correlate with RT1-Aa expression levels on thymic antigen presenting cells. Thus, our results identify a crucial role of the TAP and the quality of the MHC class I repertoire in regulating T cell selection.
Collapse
Affiliation(s)
- Jonatan Tuncel
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- * E-mail: (JT); (RH)
| | - Sabrina Haag
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Anthony C. Y. Yau
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Ulrika Norin
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Amelie Baud
- Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
| | - Erik Lönnblom
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Klio Maratou
- Physiological Genomics and Medicine Group, Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - A. Jimmy Ytterberg
- Rheumatology Unit, Department of Medicine, Karolinska University Hospital, Stockholm, Sweden
- Medical Proteomics, Department of Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden and Science for Life Laboratory, Solna, Sweden
| | - Diana Ekman
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Soley Thordardottir
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Martina Johannesson
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Alan Gillett
- Department of Clinical Neuroscience, Karolinska Institutet, Neuroimmunology Unit, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | | | - Pernilla Stridh
- Department of Clinical Neuroscience, Karolinska Institutet, Neuroimmunology Unit, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Maja Jagodic
- Department of Clinical Neuroscience, Karolinska Institutet, Neuroimmunology Unit, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Tomas Olsson
- Department of Clinical Neuroscience, Karolinska Institutet, Neuroimmunology Unit, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Alberto Fernández-Teruel
- Medical Psychology Unit, Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, School of Medicine, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain
| | - Roman A. Zubarev
- Medical Proteomics, Department of Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden and Science for Life Laboratory, Solna, Sweden
| | - Richard Mott
- Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
| | - Timothy J. Aitman
- Physiological Genomics and Medicine Group, Medical Research Council Clinical Sciences Centre, Faculty of Medicine, Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - Jonathan Flint
- Wellcome Trust Centre for Human Genetics, Oxford, United Kingdom
| | - Rikard Holmdahl
- Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- * E-mail: (JT); (RH)
| |
Collapse
|
19
|
Faje AT, Fazeli PK, Katzman D, Miller KK, Breggia A, Rosen CJ, Mendes N, Misra M, Klibanski A. Inhibition of Pref-1 (preadipocyte factor 1) by oestradiol in adolescent girls with anorexia nervosa is associated with improvement in lumbar bone mineral density. Clin Endocrinol (Oxf) 2013; 79:326-32. [PMID: 23331192 PMCID: PMC3640659 DOI: 10.1111/cen.12144] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 11/25/2012] [Accepted: 01/06/2013] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Adolescents with anorexia nervosa (AN) are amenorrheic and have decreased bone mass accrual and low bone mineral density (BMD). The regulation of mesenchymal stem cell differentiation is an important factor governing bone formation. Preadipocyte factor 1 (Pref-1), an inhibitor of adipocyte and osteoblast differentiation, is elevated in states of oestrogen deficiency. In this study, we aim to (i) investigate effects of transdermal oestradiol on Pref-1 in adolescent girls with AN, and (ii) examine associations of changes in Pref-1 with changes in lumbar BMD and bone turnover markers. DESIGN Adolescent girls with AN and normal-weight controls were studied cross-sectionally. Girls with AN were examined longitudinally in a double-blind study and received transdermal oestradiol (plus cyclic medroxyprogesterone) or placebo for 12 months. PATIENTS Sixty-nine girls (44 with AN, 25 normal-weight controls) 13-18 years were studied at baseline; 22 AN girls were followed prospectively. MEASUREMENTS Pref-1 levels, bone formation and resorption markers, and BMD. RESULTS Pref-1 levels decreased in girls with AN after treatment with transdermal oestradiol compared with placebo (-0·015 ± 0·016 vs 0·060±0·026 ng/ml, P = 0·01), although at baseline, levels did not differ in AN vs controls (0·246 ± 0·015 vs 0·267 ± 0·022 ng/ml). Changes in Pref-1 over 12 months correlated inversely with changes in lumbar BMD (r = -0·48, P = 0·02) and positively with changes in CTX (r = 0·73, P = 0·006). CONCLUSIONS For the first time, we show that Pref-1 is negatively regulated by oestradiol in adolescent girls with AN. Inhibition of Pref-1 may mediate the beneficial effects of transdermal oestradiol replacement on BMD in girls with AN.
Collapse
Affiliation(s)
- Alexander T. Faje
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Pouneh K. Fazeli
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Debra Katzman
- Division of Adolescent Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Karen K Miller
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Anne Breggia
- Maine Medical Center Research Institute, Portland, ME 04074
| | | | - Nara Mendes
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Madhusmita Misra
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
- Pediatric Endocrine Unit, Massachusetts General Hospital for Children and Harvard Medical School, Boston, MA 02114
| | - Anne Klibanski
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| |
Collapse
|
20
|
Yue LZ, Fu R, Wang HQ, Li LJ, Ruan EB, Wang GJ, Qu W, Liang Y, Guan J, Wu YH, Liu H, Song J, Wang XM, Xing LM, Shao ZH. Expression of DLK1 Gene in the Bone Marrow Cells of Patients with Myelodysplastic Syndromes and Its Clinical Significance. Cancer Biol Med 2013; 9:188-91. [PMID: 23691477 PMCID: PMC3643669 DOI: 10.7497/j.issn.2095-3941.2012.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 05/24/2012] [Indexed: 01/16/2023] Open
Abstract
OBJECTIVE This study aims to investigate the expression of delta-like 1 (DLK1) gene in the bone marrow cells of patients with myelodysplastic syndromes (MDS) and to explore its molecular characteristics for the early diagnosis of MDS. METHODS The expression of DLK1 mRNA in the bone marrow cells of cases with MDS, acute myeloid leukemia (AML), and normal control groups were measured by real-time polymerase chain reaction and were analyzed for clinical significance. RESULTS Significantly higher expression of DLK1 mRNA was observed in the bone marrow cells of MDS patients (0.7342±0.3652) compared with the normal control group (0.4801±0.1759) (P<0.05). The expression of DLK1 mRNA had a positive correlation with the proportion of bone marrow blasts (r=0.467, P<0.05). Moreover, DLK1 mRNA expression was significantly increased as MDS progressed (P<0.05). Patients with abnormal karyotypes exhibited significantly higher expression of DLK1 mRNA (0.9007±0.4334) than those with normal karyotypes (0.6411±0.2630) (P<0.05). Subsequently, patients with highly expressed DLK1 (≥0.8) presented significantly higher malignant clone burden (0.4134±0.3999) than those with lower DLK1 expression (<0.8),(0.1517±0.3109), (P<0.05). CONCLUSIONS The DLK1 gene was highly expressed in MDS patients, and was increased as MDS progressed. The expression of DLK1 mRNA was positively correlated with the proportion of the bone marrow blasts. A high expression of DLK1 gene suggested a higher malignant clone burden of MDS.
Collapse
Affiliation(s)
- Lan-Zhu Yue
- Department of Hematology, General Hospital of Tianjin Medical University, Tianjin 300052, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Appelbe OK, Yevtodiyenko A, Muniz-Talavera H, Schmidt JV. Conditional deletions refine the embryonic requirement for Dlk1. Mech Dev 2012; 130:143-59. [PMID: 23059197 DOI: 10.1016/j.mod.2012.09.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 09/13/2012] [Accepted: 09/28/2012] [Indexed: 12/21/2022]
Abstract
Numerous studies have implicated Delta-like 1 (DLK1), a transmembrane protein that shares homology with Notch ligands, in embryonic growth and differentiation. Dlk1 expression is widespread, though not ubiquitous, during early development, but is confined to a few specific cell types in adults. Adult Dlk1-expressing tissues include the Insulin-producing β-cells of the pancreas and the Growth hormone-producing somatotrophs of the pituitary gland. Previously generated Dlk1 null mice (Dlk1(Sul-pat)), display a partially penetrant neonatal lethality and a complex pattern of developmental and adult phenotypes. Here we describe the generation of a conditional Dlk1 mouse line (Dlk1(flox)) to facilitate cell type-specific deletion of the Dlk1 gene, providing a powerful system to explore each aspect of the Dlk1 null phenotype. Four tissue-specific Cre mouse lines were used to produce individual Dlk1 deletions in pancreatic β-cells, pituitary somatotrophs and the endothelial cells of the embryo and placenta, key candidates for the Dlk1 phenotype. Contrary to expectations, all of these conditional mice were fully viable, and none recapitulated any aspect of the Dlk1(Sul-pat) null mice. Dlk1 expression is therefore not essential for the normal development of β-cells, somatotrophs and endothelial cells, and the tissues responsible for the Dlk1 null phenotype remain to be identified. Dlk1(flox) mice will continue to provide an important tool for further research into the function of Dlk1.
Collapse
Affiliation(s)
- Oliver K Appelbe
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Avenue, Chicago, IL 60607, USA.
| | | | | | | |
Collapse
|
22
|
Mirshekar-Syahkal B, Haak E, Kimber GM, van Leusden K, Harvey K, O'Rourke J, Laborda J, Bauer SR, de Bruijn MFTR, Ferguson-Smith AC, Dzierzak E, Ottersbach K. Dlk1 is a negative regulator of emerging hematopoietic stem and progenitor cells. Haematologica 2012; 98:163-71. [PMID: 22801971 DOI: 10.3324/haematol.2012.070789] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The first mouse adult-repopulating hematopoietic stem cells emerge in the aorta-gonad-mesonephros region at embryonic day (E) 10.5. Their numbers in this region increase thereafter and begin to decline at E12.5, thus pointing to the possible existence of both positive and negative regulators of emerging hematopoietic stem cells. Our recent expression analysis of the aorta-gonad-mesonephros region showed that the Delta-like homologue 1 (Dlk1) gene is up-regulated in the region of the aorta-gonad-mesonephros where hematopoietic stem cells are preferentially located. To analyze its function, we studied Dlk1 expression in wild-type and hematopoietic stem cell-deficient embryos and determined hematopoietic stem and progenitor cell activity in Dlk1 knockout and overexpressing mice. Its role in hematopoietic support was studied in co-culture experiments using stromal cell lines that express varying levels of Dlk1. We show here that Dlk1 is expressed in the smooth muscle layer of the dorsal aorta and the ventral sub-aortic mesenchyme, where its expression is dependent on the hematopoietic transcription factor Runx1. We further demonstrate that Dlk1 has a negative impact on hematopoietic stem and progenitor cell activity in the aorta-gonad-mesonephros region in vivo, which is recapitulated in co-cultures of hematopoietic stem cells on stromal cells that express varying levels of Dlk1. This negative effect of Dlk1 on hematopoietic stem and progenitor cell activity requires the membrane-bound form of the protein and cannot be recapitulated by soluble Dlk1. Together, these data suggest that Dlk1 expression by cells of the aorta-gonad-mesonephros hematopoietic microenvironment limits hematopoietic stem cell expansion and is, to our knowledge, the first description of such a negative regulator in this tissue.
Collapse
Affiliation(s)
- Bahar Mirshekar-Syahkal
- Department of Haematology, Cambridge Institute for Medical Research, Wellcome Trust & MRC Stem Cell Institute, University of Cambridge, Cambridge, UK
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
HES1 opposes a PTEN-dependent check on survival, differentiation, and proliferation of TCRβ-selected mouse thymocytes. Blood 2012; 120:1439-48. [PMID: 22649105 DOI: 10.1182/blood-2011-12-395319] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The developmental progression of immature thymocytes requires cooperative input from several pathways, with Notch signals playing an indispensable role at the T-cell receptor (TCR)-β selection checkpoint. Notch signals affect the activation of the PI3K/Akt pathway, which is required for pTα/TCRβ (pre-TCR)-induced survival, differentiation, and proliferation of developing αβ-lineage thymocytes. However, the molecular players responsible for the interaction between the Notch and PI3K pathways at this critical developmental stage are unknown. Here, we show that Notch induction of Hes1 is necessary to repress the PI3K/Akt pathway inhibitor, PTEN (phosphatase and tensin homolog), which in turn facilitates pre-TCR-induced differentiation. In support of this mechanism, deletion or down-regulation of Pten overcomes the Notch signaling requirement for survival and differentiation during β-selection. In addition, c-Myc is a critical target of Notch at this stage, as c-Myc expression overcomes the Notch signaling requirement for proliferation during β-selection. Collectively, our results point to HES1, via repression of PTEN, and c-Myc as critical mediators of Notch function at the β-selection checkpoint.
Collapse
|
24
|
Rogers ED, Ramalie JR, McMurray EN, Schmidt JV. Localizing transcriptional regulatory elements at the mouse Dlk1 locus. PLoS One 2012; 7:e36483. [PMID: 22606264 PMCID: PMC3350532 DOI: 10.1371/journal.pone.0036483] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 04/06/2012] [Indexed: 11/25/2022] Open
Abstract
Much effort has focused recently on determining the mechanisms that control the allele-specific expression of genes subject to genomic imprinting, yet imprinting regulation is only one aspect of configuring appropriate expression of these genes. Imprinting control mechanisms must interact with those regulating the tissue-specific expression pattern of each imprinted gene in a cluster. Proper expression of the imprinted Delta-like 1 (Dlk1)-Maternally expressed gene 3 (Meg3) gene pair is required for normal fetal development in mammals, yet the mechanisms that control tissue-specific expression of these genes are unknown. We have used a combination of in vivo and in vitro expression assays to localize cis-regulatory elements that may regulate Dlk1 expression in the mouse embryo. A bacterial artificial chromosome transgene encompassing the Dlk1 gene and 77 kb of flanking sequence conferred expression in most endogenous Dlk1-expressing tissues. In combination with previous transgenic data, these experiments localize the majority of Dlk1 cis-regulatory elements to a 41 kb region upstream of the gene. Cross-species sequence conservation was used to further define potential regulatory elements, several of which functioned as enhancers in a luciferase expression assay. Two of these elements were able to drive expression of a lacZ reporter transgene in Dlk1-expressing tissues in the mouse embryo. The sequence proximal to Dlk1 therefore contains at least two discrete regions that may regulate tissue-specificity of Dlk1 expression.
Collapse
MESH Headings
- Animals
- Base Sequence
- Calcium-Binding Proteins
- Chromosomes, Artificial, Bacterial/genetics
- Conserved Sequence
- DNA Primers/genetics
- Enhancer Elements, Genetic
- Female
- Gene Expression Regulation, Developmental
- Genomic Imprinting
- Intercellular Signaling Peptides and Proteins/genetics
- Lac Operon
- Mice
- Mice, Transgenic
- Muscle, Skeletal/embryology
- Muscle, Skeletal/metabolism
- RNA, Long Noncoding
- RNA, Untranslated/genetics
- Regulatory Elements, Transcriptional
- Tissue Distribution
Collapse
Affiliation(s)
- Eric D. Rogers
- The Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Jenniffer R. Ramalie
- The Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Erin N. McMurray
- The Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Jennifer V. Schmidt
- The Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| |
Collapse
|
25
|
Rivero S, Díaz-Guerra MJM, Monsalve EM, Laborda J, García-Ramírez JJ. DLK2 is a transcriptional target of KLF4 in the early stages of adipogenesis. J Mol Biol 2012; 417:36-50. [PMID: 22306741 DOI: 10.1016/j.jmb.2012.01.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 01/20/2012] [Accepted: 01/21/2012] [Indexed: 12/15/2022]
Abstract
The epidermal growth factor-like protein DLK2, highly homologous to DLK1, has been identified as a modulator of adipogenesis in vitro. Knocking down Dlk2 expression prevents adipogenesis of 3T3-L1 cells but enhances that of the mesenchymal cell line C3H10T1/2. The expression of Dlk2 shows two peaks along this differentiation process: the first one, in response to 3-isobutyl-1-methylxanthine (IBMX) and dexamethasone (Dex), and the second, shortly after exposure to insulin. Nothing is known about the transcriptional regulation of Dlk2 during adipogenesis. Here, we report that, during early adipogenesis of 3T3-L1 cells, Dlk2 expression is controlled independently by IBMX and Dex. We also show that KLF4, a transcription factor critical for the control of early adipogenesis, binds directly to the Dlk2 promoter and increases Dlk2 expression in response to IBMX. Overexpression of KLF4 leads to an increase in DLK2 expression levels, whereas KLF4 knockdown downregulates the transcriptional activity of the Dlk2 promoter. Finally, we demonstrate that KLF4 regulates the basal expression of Dlk2 in C3H10T1/2 cells, and it is required for the adipogenic differentiation of those cells. These results indicate that KLF4 mediates the transcriptional regulation of Dlk2 in response to IBMX during the early stages of adipogenesis.
Collapse
Affiliation(s)
- Samuel Rivero
- Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Medicina/Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, 02006 Albacete, Spain
| | | | | | | | | |
Collapse
|
26
|
Tian C, Zheng G, Cao Z, Li Q, Ju Z, Wang J, Yuan W, Cheng T. Hes1 mediates the different responses of hematopoietic stem and progenitor cells to T cell leukemic environment. Cell Cycle 2012; 12:322-31. [PMID: 23255132 DOI: 10.4161/cc.23160] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Normal hematopoiesis is suppressed during the development of leukemia. In the T-ALL leukemia mouse model described in our recent study (Hu X, et al. Blood 2009), the impacts of leukemic environment on normal hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were distinct, in that normal HSCs were preserved in part because of increased mitotic quiescence of HSCs and resulting exhaustion of HPCs proliferation. Stem cell factor (SCF) secreted by leukemic cells in Nalm6 B-ALL model was previously suggested to force normal HSCs/HPCs out of their bone marrow niches and allow leukemic cells to occupy the niches (Colmone A, et al. Science 2008). Here we found that stem cell factor (SCF) expression in PB and BM of T-ALL model was increased, but SCF mRNA and protein levels in normal hematopoietic cells were higher than those in leukemia cells, which suggested that upregulated SCF was mainly contributed by non-leukemic cells in response to the leukemia development. To further elucidate the molecular mechanisms, microarray analysis was conducted on normal HSCs in this model and verified by real-time RT-PCR. The expression of Hes1 and its downstream target p21 were elevated in normal HSCs, whereas their expression showed no significant alteration in HPCs. Interestingly, although overexpression of Hes1 by retroviral infection inhibited the in vitro colony formation of normal hematopoietic cells, in vivo results demonstrated that normal Lin(-) cells and HSPCs were better preserved when normal Lin(-) cells with Hes1 overexpression were co-transplanted with T-ALL leukemia cells. Our results suggested that the differential expression of Hes1 between HSCs and HPCs resulted in the distinct responses of these cells to the leukemic condition, and that overexpression of Hes1 could enhance normal HSPCs in the leukemic environment.
Collapse
Affiliation(s)
- Chen Tian
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Rivero S, Ruiz-García A, Díaz-Guerra MJM, Laborda J, García-Ramírez JJ. Characterization of a proximal Sp1 response element in the mouse Dlk2 gene promoter. BMC Mol Biol 2011; 12:52. [PMID: 22185379 PMCID: PMC3296630 DOI: 10.1186/1471-2199-12-52] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 12/20/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND DLK2 is an EGF-like membrane protein, closely related to DLK1, which is involved in adipogenesis. Both proteins interact with the NOTCH1 receptor and are able to modulate its activation. The expression of the gene Dlk2 is coordinated with that of Dlk1 in several tissues and cell lines. Unlike Dlk1, the mouse Dlk2 gene and its locus at chromosome 17 are not fully characterized. RESULTS The goal of this work was the characterization of Dlk2 mRNA, as well as the analysis of the mechanisms that control its basal transcription. First, we analyzed the Dlk2 transcripts expressed by several mouse cells lines and tissues, and mapped the transcription start site by 5' Rapid Amplification of cDNA Ends. In silico analysis revealed that Dlk2 possesses a TATA-less promoter containing minimal promoter elements associated with a CpG island, and sequences for Inr and DPE elements. Besides, it possesses six GC-boxes, considered as consensus sites for the transcription factor Sp1. Indeed, we report that Sp1 directly binds to the Dlk2 promoter, activates its transcription, and regulates its level of expression. CONCLUSIONS Our results provide the first characterization of Dlk2 transcripts, map the location of the Dlk2 core promoter, and show the role of Sp1 as a key regulator of Dlk2 transcription, providing new insights into the molecular mechanisms that contribute to the expression of the Dlk2 gene.
Collapse
Affiliation(s)
- Samuel Rivero
- Facultad de Medicina/Centro Regional de Investigaciones Biomédicas, Universidad de Castilla-La Mancha, Calle Almansa 14, 02006 Albacete, Spain
| | | | | | | | | |
Collapse
|
28
|
DLK1 Promotes Neurogenesis of Human and Mouse Pluripotent Stem Cell-Derived Neural Progenitors Via Modulating Notch and BMP Signalling. Stem Cell Rev Rep 2011; 8:459-71. [DOI: 10.1007/s12015-011-9298-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
29
|
Abstract
T cells are the key mediators in cell-mediated immunity. Their development and maturation involve a complex variety of interactions with nonlymphoid cell products and receptors. Highly specialized to defend against bacterial and viral infections, T cells also mediate immune surveillance against tumor cells and react to foreign tissues. T cell progenitors originate in the bone marrow and, through a series of defined and coordinated developmental stages, enter the thymus, differentiate, undergo selection, and eventually mature into functional T cells. The steps in this process are regulated through a complex transcriptional network, specific receptor-ligand pair interactions, and sensitization to trophic factors, which mediate the homing, proliferation, survival, and differentiation of developing T cells. This review examines the processes and pathways involved in the highly orchestrated development of T cell fate specification under physiological as well as pathological conditions.
Collapse
Affiliation(s)
- Ute Koch
- Ecole Polytechnique Fédérale de Lausanne, Swiss Institute for Experimental Cancer Research, 1015 Lausanne, Switzerland
| | | |
Collapse
|
30
|
Sánchez-Solana B, Nueda ML, Ruvira MD, Ruiz-Hidalgo MJ, Monsalve EM, Rivero S, García-Ramírez JJ, Díaz-Guerra MJM, Baladrón V, Laborda J. The EGF-like proteins DLK1 and DLK2 function as inhibitory non-canonical ligands of NOTCH1 receptor that modulate each other's activities. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:1153-64. [DOI: 10.1016/j.bbamcr.2011.03.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 02/19/2011] [Accepted: 03/07/2011] [Indexed: 12/23/2022]
|
31
|
Abstract
Unlike conventional T cells, which are exported from the thymus as naive cells and acquire effector functions upon antigen encounter in the periphery, a subset of γδ T cells differentiates into effectors that produce IL-17 within the fetal thymus. We demonstrate here that intrathymic development of the naturally occurring IL-17-producing γδ T cells is independent of STAT3 and partly dependent on RORγt. Comparative gene-expression analysis identified Hes1, one of the basic helix-loop-helix proteins involved in Notch signaling, as a factor specifically expressed in IL-17-producing γδ T cells. Hes1 is critically involved in the development of IL-17-producing γδ T cells, as evidenced by their severe decrease in the thymi of Hes1-deficient fetal mice. Delta-like 4 (Dll4)-expressing stromal cells support the development of IL-17-producing γδ T cells in vitro. In addition, conditional Hes1 ablation in peripheral γδ T cells decreases their IL-17 production but not their IFN-γ production. These results reveal a unique differentiation pathway of IL-17-producing γδ T cells.
Collapse
|
32
|
Aberrant expression of imprinted genes in post-implantation rat embryos. Life Sci 2011; 88:634-43. [DOI: 10.1016/j.lfs.2011.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 01/06/2011] [Accepted: 01/20/2011] [Indexed: 11/19/2022]
|
33
|
Abstract
Hes1 is a direct Notch1 target; however, its precise function is unclear. In this issue of Immunity, Wendorff et al. (2010) report that Hes1 regulates the number of T cell progenitors and has important functions in both the induction and maintenance of T cell leukemia.
Collapse
Affiliation(s)
- Warren S Pear
- Department of Pathology and Laboratory Medicine and Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
34
|
Wendorff AA, Koch U, Wunderlich FT, Wirth S, Dubey C, Brüning JC, MacDonald HR, Radtke F. Hes1 is a critical but context-dependent mediator of canonical Notch signaling in lymphocyte development and transformation. Immunity 2010; 33:671-84. [PMID: 21093323 DOI: 10.1016/j.immuni.2010.11.014] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 08/19/2010] [Accepted: 09/17/2010] [Indexed: 01/03/2023]
Abstract
Although canonical Notch signaling regulates multiple hematopoietic lineage decisions including T cell and marginal zone B cell fate specification, the downstream molecular mediators of Notch function are largely unknown. We showed here that conditional inactivation of Hes1, a well-characterized Notch target gene, in adult murine bone marrow (BM) cells severely impaired T cell development without affecting other Notch-dependent hematopoietic lineages such as marginal zone B cells. Competitive mixed BM chimeras, intrathymic transfer experiments, and in vitro culture of BM progenitors on Delta-like-expressing stromal cells further demonstrated that Hes1 is required for T cell lineage commitment, but dispensable for Notch-dependent thymocyte maturation through and beyond the beta selection checkpoint. Furthermore, our data strongly suggest that Hes1 is essential for the development and maintenance of Notch-induced T cell acute lymphoblastic leukemia. Collectively, our studies identify Hes1 as a critical but context-dependent mediator of canonical Notch signaling in the hematopoietic system.
Collapse
Affiliation(s)
- Agnieszka A Wendorff
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Institute for Experimental Cancer Research (ISREC), Station 19, 1015 Lausanne, Switzerland
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Kim Y. The effects of nutrient depleted microenvironments and delta-like 1 homologue (DLK1) on apoptosis in neuroblastoma. Nutr Res Pract 2010; 4:455-61. [PMID: 21286402 PMCID: PMC3029785 DOI: 10.4162/nrp.2010.4.6.455] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 09/01/2010] [Accepted: 10/05/2010] [Indexed: 11/06/2022] Open
Abstract
The tumor microenvironment, particularly sufficient nutrition and oxygen supply, is important for tumor cell survival. Nutrition deprivation causes cancer cell death. Since apoptosis is a major mechanism of neuronal loss, we explored neuronal apoptosis in various microenvironment conditions employing neuroblastoma (NB) cells. To investigate the effects of tumor malignancy and differentiation on apoptosis, the cells were exposed to poor microenvironments characterized as serum-free, low-glucose, and hypoxia. Incubation of the cells in serum-free and low-glucose environments significantly increased apoptosis in less malignant and more differentiated N-type IMR32 cells, whereas more malignant and less differentiated I-type BE(2)C cells were not affected by those treatments. In contrast, hypoxia (1% O2) did not affect apoptosis despite cell malignancy. It is suggested that DLK1 constitutes an important stem cell pathway for regulating self-renewal, clonogenicity, and tumorigenicity. This raises questions about the role of DLK1 in the cellular resistance of cancer cells under poor microenvironments, which cancer cells normally encounter. In the present study, DLK1 overexpression resulted in marked protection from apoptosis induced by nutrient deprivation. This in vitro model demonstrated that increasing severity of nutrition deprivation and knock-down of DLK1 caused greater apoptotic death, which could be a useful strategy for targeted therapies in fighting NB as well as for evaluating how nutrient deprived cells respond to therapeutic manipulation.
Collapse
Affiliation(s)
- Yuri Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, 11-1 Daehyun-dong, Seodaemun-gu, Seoul 120-750, Korea
| |
Collapse
|
36
|
Shapiro MJ, Shapiro VS. Transcriptional repressors, corepressors and chromatin modifying enzymes in T cell development. Cytokine 2010; 53:271-81. [PMID: 21163671 DOI: 10.1016/j.cyto.2010.11.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2010] [Revised: 11/12/2010] [Accepted: 11/18/2010] [Indexed: 01/13/2023]
Abstract
Gene expression is regulated by the combined action of transcriptional activators and transcriptional repressors. Transcriptional repressors function by recruiting corepressor complexes containing histone-modifying enzymes to specific sites within DNA. Chromatin modifying complexes are subsequently recruited, either directly by transcriptional repressors, or indirectly via corepressor complexes and/or histone modifications, to remodel chromatin into either a transcription-friendly 'open' form or an inhibitory 'closed' form. Transcriptional repressors, corepressors and chromatin modifying complexes play critical roles throughout T cell development. Here, we highlight those genes that function to repress transcription and that have been shown to be required for T cell development.
Collapse
|
37
|
Liu H, Chi AW, Arnett KL, Chiang MY, Xu L, Shestova O, Wang H, Li YM, Bhandoola A, Aster JC, Blacklow SC, Pear WS. Notch dimerization is required for leukemogenesis and T-cell development. Genes Dev 2010; 24:2395-407. [PMID: 20935071 PMCID: PMC2964750 DOI: 10.1101/gad.1975210] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 09/13/2010] [Indexed: 12/30/2022]
Abstract
Notch signaling regulates myriad cellular functions by activating transcription, yet how Notch selectively activates different transcriptional targets is poorly understood. The core Notch transcriptional activation complex can bind DNA as a monomer, but it can also dimerize on DNA-binding sites that are properly oriented and spaced. However, the significance of Notch dimerization is unknown. Here, we show that dimeric Notch transcriptional complexes are required for T-cell maturation and leukemic transformation but are dispensable for T-cell fate specification from a multipotential precursor. The varying requirements for Notch dimerization result from the differential sensitivity of specific Notch target genes. In particular, c-Myc and pre-T-cell antigen receptor α (Ptcra) are dimerization-dependent targets, whereas Hey1 and CD25 are not. These findings identify functionally important differences in the responsiveness among Notch target genes attributable to the formation of higher-order complexes. Consequently, it may be possible to develop a new class of Notch inhibitors that selectively block outcomes that depend on Notch dimerization (e.g., leukemogenesis).
Collapse
MESH Headings
- Animals
- Base Sequence
- Binding Sites
- Cell Line, Tumor
- Cell Proliferation
- Cells, Cultured
- Flow Cytometry
- Leukemia/genetics
- Leukemia/metabolism
- Leukemia/pathology
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred C57BL
- Models, Molecular
- Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/genetics
- Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/metabolism
- Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/pathology
- Protein Multimerization
- Protein Structure, Tertiary
- Proto-Oncogene Proteins c-myc/genetics
- Proto-Oncogene Proteins c-myc/metabolism
- Receptor, Notch1/chemistry
- Receptor, Notch1/genetics
- Receptor, Notch1/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Homology, Nucleic Acid
- Signal Transduction/genetics
- Signal Transduction/physiology
- T-Lymphocytes/cytology
- T-Lymphocytes/metabolism
- Transcription, Genetic
Collapse
Affiliation(s)
- Hudan Liu
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Anthony W.S. Chi
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Kelly L. Arnett
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
- Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA
| | - Mark Y. Chiang
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Division of Hematology-Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Lanwei Xu
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Olga Shestova
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Hongfang Wang
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Yue-Ming Li
- Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Avinash Bhandoola
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Jon C. Aster
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Stephen C. Blacklow
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
- Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA
| | - Warren S. Pear
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| |
Collapse
|
38
|
Kim Y. Effect of retinoic acid and delta-like 1 homologue (DLK1) on differentiation in neuroblastoma. Nutr Res Pract 2010; 4:276-82. [PMID: 20827342 PMCID: PMC2933444 DOI: 10.4162/nrp.2010.4.4.276] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 06/30/2010] [Accepted: 07/05/2010] [Indexed: 01/06/2023] Open
Abstract
The principal objective of this study was to evaluate the chemopreventive and therapeutic effects of a combination of all-trans-retinoic acid (RA) and knockdown of delta-like 1 homologue (Drosophila) (DLK1) on neuroblastoma, the most common malignant disease in children. As unfavorable neuroblastoma is poorly differentiated, neuroblastoma cell was induced differentiation by RA or DLK1 knockdown. Neuroblastoma cells showed elongated neurite growth, a hallmark of neuronal differentiation at various doses of RA, as well as by DLK1 knockdown. In order to determine whether or not a combination of RA and DLK1 knockdown exerts a greater chemotherapeutic effect on neuroblastoma, cells were incubated at 10 nM RA after being transfected with SiRNA-DLK1. Neuronal differentiation was increased more by a combination of RA and DLK1 knockdown than by single treatment. Additionally, in order to assess the signal pathway of neuroblastoma differentiation induced by RA and DLK1 knockdown, treatment with the specific MEK/ERK inhibitors, U0126 and PD 98059, was applied to differentiated neuroblastoma cells. Differentiation induced by RA and DLK1 knockdown increased ERK phosphorylation. The MEK/ERK inhibitor U0126 completely inhibited neuronal differentiation induced by both RA and DLK1 knockdown, whereas PD98059 partially blocked neuronal differentiation. After the withdrawal of inhibitors, cellular differentiation was fully recovered. This study is, to the best of our knowledge, the first to demonstrate that the specific inhibitors of the MEK/ERK pathway, U0126 and PD98059, exert differential effects on the ERK phosphorylation induced by RA or DLK1 knockdown. Based on the observations of this study, it can be concluded that a combination of RA and DLK1 knockdown increases neuronal differentiation for the control of the malignant growth of human neuroblastomas, and also that both MEK1 and MEK2 are required for the differentiation induced by RA and DLK1 knockdown.
Collapse
Affiliation(s)
- Yuri Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, 11-1 Daehyun-dong, Seodaemun-gu, Seoul 120-750, Korea
| |
Collapse
|
39
|
Andersen DC, Jensen CH, Schneider M, Nossent AY, Eskildsen T, Hansen JL, Teisner B, Sheikh SP. MicroRNA-15a fine-tunes the level of Delta-like 1 homolog (DLK1) in proliferating 3T3-L1 preadipocytes. Exp Cell Res 2010; 316:1681-91. [PMID: 20385127 DOI: 10.1016/j.yexcr.2010.04.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Revised: 02/28/2010] [Accepted: 04/04/2010] [Indexed: 11/16/2022]
Abstract
Delta like 1 homolog (Dlk1) exists in both transmembrane and soluble molecular forms, and is implicated in cellular growth and plays multiple roles in development, tissue regeneration, and cancer. Thus, DLK1 levels are critical for cell function, and abnormal DLK1 expression can be lethal; however, little is known about the underlying mechanisms. We here report that miR-15a modulates DLK1 levels in preadipocytes thus providing a mechanism for DLK1 regulation that further links it to cell cycle arrest and cancer since miR-15a is deregulated in these processes. In preadipocytes, miR-15a increases with cell density, and peaks at the same stage where membrane DLK1(M) and soluble DLK1(S) are found at maximum levels. Remarkably, miR-15a represses the amount of all Dlk1 variants at the mRNA level but also the level of DLK1(M) protein while it increases the amount of DLK1(S) supporting a direct repression of DLK1 and a parallel effect on the protease that cleaves off the DLK1 from the membrane. In agreement with previous studies, we found that miR-15a represses cell numbers, but additionally, we report that miR-15a also increases cell size. Conversely, anti-miR-15a treatment decreases cell size while increasing cell numbers, scenarios that were completely rescued by addition of purified DLK1(S). Our data thus imply that miR-15a regulates cell size and proliferation by fine-tuning Dlk1 among others, and further emphasize miR-15a and DLK1 levels to play important roles in growth signaling networks.
Collapse
Affiliation(s)
- Ditte C Andersen
- Laboratory of Molecular and Cellular Cardiology, Department of Biochemistry, Pharmacology and Genetics, Odense University Hospital, University of Southern Denmark, Winsløwparken 21.3, DK-5000 Odense C, Denmark
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Sultana DA, Bell JJ, Zlotoff DA, De Obaldia ME, Bhandoola A. Eliciting the T cell fate with Notch. Semin Immunol 2010; 22:254-60. [PMID: 20627765 DOI: 10.1016/j.smim.2010.04.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 04/23/2010] [Indexed: 10/19/2022]
Abstract
Multipotent progenitors arrive at the thymus via the blood. Constraining the non-T cell fates of these progenitors while promoting the T cell fate is a major task of the thymus. Notch appears to be the initial trigger for a developmental program that eventually results in T cell lineage commitment. Several downstream targets of Notch are known, but the specific roles of each are poorly understood. A greater understanding of how Notch and other thymic signals direct progenitors to a T cell fate could be useful for translational work. For example, such work could eventually allow for the generation of fully competent T cells in vitro that could supplement the waning T cell numbers and function in the elderly and boost T cell-mediated immunity in patients with immunodeficiency and after stem cell transplantation.
Collapse
Affiliation(s)
- Dil Afroz Sultana
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA
| | | | | | | | | |
Collapse
|
41
|
Characterization of a novel murine preadipocyte line, AP-18, isolated from subcutaneous tissue: analysis of adipocyte-related gene expressions. Cell Biol Int 2010; 34:293-9. [DOI: 10.1042/cbi20090063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
42
|
Wang Y, Hudak C, Sul HS. Role of preadipocyte factor 1 in adipocyte differentiation. ACTA ACUST UNITED AC 2010; 5:109-115. [PMID: 20414356 DOI: 10.2217/clp.09.80] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Preadipocyte factor 1 (Pref-1) is an EGF-repeat-containing transmembrane protein that inhibits adipogenesis. The extracellular domain of Pref-1 is cleaved by TNF-α converting enzyme to generate the biologically active soluble form of Pref-1. The role of Pref-1 in adipogenesis has been firmly established by in vitro and in vivo studies. Pref-1 activates ERK/MAPK and upregulates Sox9 expression to inhibit adipocyte differentiation. Sox9 directly binds to the promoter regions of CCAAT/enhancer-binding protein-β and CCAAT/enhancer-binding protein-δ in order to suppress their promoter activities in preventing adipocyte differentiation. Here, we describe the function of Pref-1 in adipocyte differentiation and the recent findings on the mechanisms by which Pref-1 inhibits adipocyte differentiation.
Collapse
Affiliation(s)
- Yuhui Wang
- Department of Nutritional Science & Toxicology, University of California, Berkeley, CA 94720, USA, Tel.: +1 510 642 3978, ,
| | | | | |
Collapse
|
43
|
Miyaoka Y, Tanaka M, Imamura T, Takada S, Miyajima A. A novel regulatory mechanism for Fgf18 signaling involving cysteine-rich FGF receptor (Cfr) and delta-like protein (Dlk). Development 2010; 137:159-67. [PMID: 20023171 DOI: 10.1242/dev.041574] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Fibroblast growth factors (FGFs) transduce signals through FGF receptors (FGFRs) and have pleiotropic functions. Besides signal-transducing FGFRs, cysteine-rich FGF receptor (Cfr; Glg1) is also known to bind some FGFs, although its physiological functions remain unknown. In this study, we generated Cfr-deficient mice and found that some of them die perinatally, and show growth retardation, tail malformation and cleft palate. These phenotypes are strikingly similar to those of Fgf18-deficient mice, and we revealed interaction between Cfr and Fgf18 both genetically and physically, suggesting functional cooperation. Consistently, introduction of Cfr facilitated Fgf18-dependent proliferation of Ba/F3 cells expressing Fgfr3c. In addition, we uncovered binding between Cfr and delta-like protein (Dlk), and noticed that Cfr-deficient mice are also similar to Dlk-transgenic mice, indicating that Cfr and Dlk function in opposite ways. Interestingly, we also found that Dlk interrupts the binding between Cfr and Fgf18. Thus, the Fgf18 signaling pathway seems to be finely tuned by Cfr and Dlk for skeletal development. This study reveals a novel regulatory mechanism for Fgf18 signaling involving Cfr and Dlk.
Collapse
Affiliation(s)
- Yuichiro Miyaoka
- Laboratory of Cell Growth and Differentiation, Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | | | | | | | | |
Collapse
|
44
|
Kim Y, Lin Q, Zelterman D, Yun Z. Hypoxia-regulated delta-like 1 homologue enhances cancer cell stemness and tumorigenicity. Cancer Res 2010; 69:9271-80. [PMID: 19934310 DOI: 10.1158/0008-5472.can-09-1605] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Reduced oxygenation, or hypoxia, inhibits differentiation and facilitates stem cell maintenance. Hypoxia commonly occurs in solid tumors and promotes malignant progression. Hypoxic tumors are aggressive and exhibit stem cell-like characteristics. It remains unclear, however, whether and how hypoxia regulates cancer cell differentiation and maintains cancer cell stemness. Here, we show that hypoxia increases the expression of the stem cell gene DLK1, or delta-like 1 homologue (Drosophila), in neuronal tumor cells. Inhibition of DLK1 enhances spontaneous differentiation, decreases clonogenicity, and reduces in vivo tumor growth. Overexpression of DLK1 inhibits differentiation and enhances tumorigenic potentials. We further show that the DLK1 cytoplasmic domain, especially Tyrosine339 and Serine355, is required for maintaining both clonogenicity and tumorigenicity. Because elevated DLK1 expression is found in many tumor types, our observations suggest that hypoxia and DLK1 may constitute an important stem cell pathway for the regulation of cancer stem cell-like functionality and tumorigenicity.
Collapse
Affiliation(s)
- Yuri Kim
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut 06520-8040, USA
| | | | | | | |
Collapse
|
45
|
Hes1 immortalizes committed progenitors and plays a role in blast crisis transition in chronic myelogenous leukemia. Blood 2009; 115:2872-81. [PMID: 19861684 DOI: 10.1182/blood-2009-05-222836] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Hairy enhancer of split 1 (Hes1) is a basic helix-loop-helix transcriptional repressor that affects differentiation and often helps maintain cells in an immature state in various tissues. Here we show that retroviral expression of Hes1 immortalizes common myeloid progenitors (CMPs) and granulocyte-macrophage progenitors (GMPs) in the presence of interleukin-3, conferring permanent replating capability on these cells. Whereas these cells did not develop myeloproliferative neoplasms when intravenously administered to irradiated mice, the combination of Hes1 and BCR-ABL in CMPs and GMPs caused acute leukemia resembling blast crisis of chronic myelogenous leukemia (CML), resulting in rapid death of the recipient mice. On the other hand, BCR-ABL alone caused CML-like disease when expressed in c-Kit-positive, Sca-1-positive, and lineage-negative hematopoietic stem cells (KSLs), but not committed progenitors CMPs or GMPs, as previously reported. Leukemic cells derived from Hes1 and BCR-ABL-expressing CMPs and GMPs were more immature than those derived from BCR-ABL-expressing KSLs. Intriguingly, Hes1 was highly expressed in 8 of 20 patients with CML in blast crisis, but not in the chronic phase, and dominant negative Hes1 retarded the growth of some CML cell lines expressing Hes1. These results suggest that Hes1 is a key molecule in blast crisis transition in CML.
Collapse
|
46
|
Fleming-Waddell JN, Olbricht GR, Taxis TM, White JD, Vuocolo T, Craig BA, Tellam RL, Neary MK, Cockett NE, Bidwell CA. Effect of DLK1 and RTL1 but not MEG3 or MEG8 on muscle gene expression in Callipyge lambs. PLoS One 2009; 4:e7399. [PMID: 19816583 PMCID: PMC2756960 DOI: 10.1371/journal.pone.0007399] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Accepted: 09/15/2009] [Indexed: 12/30/2022] Open
Abstract
Callipyge sheep exhibit extreme postnatal muscle hypertrophy in the loin and hindquarters as a result of a single nucleotide polymorphism (SNP) in the imprinted DLK1-DIO3 domain on ovine chromosome 18. The callipyge SNP up-regulates the expression of surrounding transcripts when inherited in cis without altering their allele-specific imprinting status. The callipyge phenotype exhibits polar overdominant inheritance since only paternal heterozygous animals have muscle hypertrophy. Two studies were conducted profiling gene expression in lamb muscles to determine the down-stream effects of over-expression of paternal allele-specific DLK1 and RTL1 as well as maternal allele-specific MEG3, RTL1AS and MEG8, using Affymetrix bovine expression arrays. A total of 375 transcripts were differentially expressed in callipyge muscle and 25 transcripts were subsequently validated by quantitative PCR. The muscle-specific expression patterns of most genes were similar to DLK1 and included genes that are transcriptional repressors or affect feedback mechanisms in beta-adrenergic and growth factor signaling pathways. One gene, phosphodiesterase 7A had an expression pattern similar to RTL1 expression indicating a biological activity for RTL1 in muscle. Only transcripts that localize to the DLK1-DIO3 domain were affected by inheritance of a maternal callipyge allele. Callipyge sheep are a unique model to study over expression of both paternal allele-specific genes and maternal allele-specific non-coding RNA with an accessible and nonlethal phenotype. This study has identified a number of genes that are regulated by DLK1 and RTL1 expression and exert control on postnatal skeletal muscle growth. The genes identified in this model are primary candidates for naturally regulating postnatal muscle growth in all meat animal species, and may serve as targets to ameliorate muscle atrophy conditions including myopathic diseases and age-related sarcopenia.
Collapse
Affiliation(s)
| | - Gayla R. Olbricht
- Department of Statistics, Purdue University, West Lafayette, Indiana, United States of America
| | - Tasia M. Taxis
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Animal Sciences Division, University of Missouri, Columbia, Missouri, United States of America
| | - Jason D. White
- School of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Tony Vuocolo
- CSIRO Livestock Industries, St. Lucia, Queensland, Australia
| | - Bruce A. Craig
- Department of Statistics, Purdue University, West Lafayette, Indiana, United States of America
| | - Ross L. Tellam
- CSIRO Livestock Industries, St. Lucia, Queensland, Australia
| | - Mike K. Neary
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Noelle E. Cockett
- Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Christopher A. Bidwell
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana, United States of America
| |
Collapse
|
47
|
Kim JA, Kang YJ, Park G, Kim M, Park YO, Kim H, Leem SH, Chu IS, Lee JS, Jho EH, Oh IH. Identification of a stroma-mediated Wnt/beta-catenin signal promoting self-renewal of hematopoietic stem cells in the stem cell niche. Stem Cells 2009; 27:1318-29. [PMID: 19489023 DOI: 10.1002/stem.52] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
With contrasting observations on the effects of beta-catenin on hematopoietic stem cells (HSCs), the precise role of Wnt/beta-catenin signals on HSC regulation remains unclear. Here, we show a distinct mode of Wnt/beta-catenin signal that can regulate HSCs in a stroma-dependent manner. Stabilization of beta-catenin in the bone marrow stromal cells promoted maintenance and self-renewal of HSCs in a contact-dependent manner, whereas direct stabilization in hematopoietic cells caused loss of HSCs. Interestingly, canonical Wnt receptors and beta-catenin accumulation were predominantly enriched in the stromal rather than the hematopoietic compartment of bone marrows. Moreover, the active form of beta-catenin accumulated selectively in the trabecular endosteum in "Wnt 3a-stimulated" or "irradiation-stressed," but not in "steady-state" marrows. Notably, notch ligands were induced in Wnt/beta-catenin activated bone marrow stroma and downstream notch signal activation was seen in the HSCs in contact with the activated stroma. Taken together, Wnt/beta-catenin activated stroma and their cross-talk with HSCs may function as a physiologically regulated microenvironmental cue for HSC self-renewal in the stem cell niche.
Collapse
Affiliation(s)
- Jin-A Kim
- Catholic Cell Therapy Center and Department of Cellular Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
Preadipocyte factor-1 [Pref-1; also called Dlk1 (Delta-like protein 1)] is made as an epidermal growth factor-repeat containing transmembrane protein that produces a biologically active soluble form by TNF-alpha-converting enzyme (TACE)-mediated cleavage. Soluble Pref-1 activates the MAPK kinase/ERK pathway. In adipose tissue, Pref-1 is specifically expressed in preadipocytes but not in adipocytes and thus is used as a preadipocyte marker. Inhibition of adipogenesis by Pref-1 has been well established in vitro as well as in vivo by ablation and overexpression of Pref-1. SRY (sex determining region Y)-box 9 (Sox9), a transcription factor expressed in preadipocytes to suppress CCAAT enhancer binding protein beta and (C/EBP) delta expression, is required to be down-regulated before adipocyte differentiation can proceed. By activating MAPK kinase/ERK, Pref-1 prevents down-regulation of Sox9, resulting in inhibition of adipogenesis. Furthermore, by inducing Sox9, Pref-1 promotes chondrogenic induction of mesenchymal cells but prevents chondrocyte maturation as well as osteoblast differentiation. Thus, Pref-1 directs multipotent mesenchymal cells toward the chondrogenic lineage but inhibits differentiation into adipocytes as well as osteoblasts and chondrocytes. Pref-1, encoded by an imprinted gene, has also been detected in progenitor cells in various tissues during regeneration and therefore may have a more general role in maintaining cells in an undifferentiated state.
Collapse
Affiliation(s)
- Hei Sook Sul
- Department of Nutritional Science and Toxicology, University of California, Berkeley, California 94720, USA.
| |
Collapse
|
49
|
Kutlesa S, Zayas J, Valle A, Levy RB, Jurecic R. T-cell differentiation of multipotent hematopoietic cell line EML in the OP9-DL1 coculture system. Exp Hematol 2009; 37:909-23. [PMID: 19447159 DOI: 10.1016/j.exphem.2009.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Revised: 05/04/2009] [Accepted: 05/07/2009] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Multipotent hematopoietic cell line EML can differentiate into myeloid, erythroid, megakaryocytic, and B-lymphoid lineages, but it remained unknown whether EML cells have T-cell developmental potential as well. The goal of this study was to determine whether the coculture with OP9 stromal cells expressing Notch ligand Delta-like 1 (OP9-DL1) could induce differentiation of EML cells into T-cell lineage. MATERIALS AND METHODS EML cells were cocultured with control OP9 or OP9-DL1 stromal cells in the presence of cytokines (stem cell factor, interleukin-7, and Fms-like tyrosine kinase 3 ligand). Their T-cell lineage differentiation was assessed through flow cytometry and reverse transcription polymerase chain reaction expression analysis of cell surface markers and genes characterizing and associated with specific stages of T-cell development. RESULTS The phenotypic, molecular, and functional analysis has revealed that in EML/OP9-DL1 cocultures with cytokines, but not in control EML/OP9 cocultures, EML cell line undergoes T-cell lineage commitment and differentiation. In OP9-DL1 cocultures, EML cell line has differentiated into cells that 1) resembled double-negative, double-positive, and single-positive stages of T-cell development; 2) initiated expression of GATA-3, Pre-Talpha, RAG-1, and T-cell receptor-Vbeta genes; and 3) produced interferon-gamma in response to T-cell receptor stimulation. CONCLUSIONS These results support the notion that EML cell line has the capacity for T-cell differentiation. Remarkably, induction of T-lineage gene expression and differentiation of EML cells into distinct stages of T-cell development were very similar to previously described T-cell differentiation of adult hematopoietic stem cells and progenitors in OP9-DL1 cocultures. Thus, EML/OP9-DL1 coculture could be a useful experimental system to study the role of particular genes in T-cell lineage specification, commitment, and differentiation.
Collapse
Affiliation(s)
- Snjezana Kutlesa
- Department of Microbiology and Immunology, Miller School of Medicine, University of Miami, Miami, Fla. 33136, USA
| | | | | | | | | |
Collapse
|
50
|
Wang Y, Sul HS. Pref-1 regulates mesenchymal cell commitment and differentiation through Sox9. Cell Metab 2009; 9:287-302. [PMID: 19254573 PMCID: PMC2673480 DOI: 10.1016/j.cmet.2009.01.013] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 12/01/2008] [Accepted: 01/30/2009] [Indexed: 01/29/2023]
Abstract
Pref-1 is an EGF repeat-containing transmembrane protein that produces a biologically active soluble form by TACE-mediated cleavage. Although Pref-1 inhibition of adipogenesis has been well established, the specific target(s) of Pref-1 or the Pref-1 function in mesenchymal cell commitment/differentiation are not known. Here, we show that Sox9 downregulation is required for adipocyte differentiation and that Pref-1 inhibits adipocyte differentiation through upregulating Sox9 expression. Sox9 directly binds to the promoter regions of C/EBPbeta and C/EBPdelta to suppress their promoter activity, preventing adipocyte differentiation. Furthermore, we also show that, by inducing Sox9, Pref-1 promotes chondrogenic induction of mesenchymal cells but prevents chondrocyte maturation as well as osteoblast differentiation, with supporting in vivo evidence in Pref-1 null and Pref-1 transgenic mice. Thus, Sox9 is a Pref-1 target, and Pref-1 directs multipotent mesenchymal cells to the chondrogenic lineage but inhibits differentiation into adipocytes as well as osteoblasts and chondrocytes.
Collapse
Affiliation(s)
- Yuhui Wang
- Department of Nutritional Science and Toxicology, University of California, Berkeley, Berkeley, CA 94720, USA
| | | |
Collapse
|