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Halder D, Park JH, Choi MR, Chai JC, Lee YS, Mandal C, Jung KH, Chai YG. Chronic ethanol exposure increasesgoosecoid(GSC) expression in human embryonic carcinoma cell differentiation. J Appl Toxicol 2013; 34:66-75. [DOI: 10.1002/jat.2832] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/04/2012] [Accepted: 09/07/2012] [Indexed: 01/01/2023]
Affiliation(s)
- Debasish Halder
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
| | - Ji Hyun Park
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
| | - Mi Ran Choi
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
| | - Jin Choul Chai
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
| | - Young Seek Lee
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
| | - Chanchal Mandal
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
| | - Kyoung Hwa Jung
- Institute of Natural Science and Technology; Hanyang University; Ansan Korea
| | - Young Gyu Chai
- Division of Molecular and Life Sciences; Hanyang University; Ansan Korea
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2
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Li C, Li YP, Fu XY, Deng CX. Anterior visceral endoderm SMAD4 signaling specifies anterior embryonic patterning and head induction in mice. Int J Biol Sci 2010; 6:569-83. [PMID: 20941375 PMCID: PMC2952407 DOI: 10.7150/ijbs.6.569] [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: 09/16/2010] [Accepted: 09/27/2010] [Indexed: 12/22/2022] Open
Abstract
SMAD4 serves as a common mediator for signaling of TGF-β superfamily. Previous studies illustrated that SMAD4-null mice die at embryonic day 6.5 (E6.5) due to failure of mesoderm induction and extraembryonic defects; however, functions of SMAD4 in each germ layer remain elusive. To investigate this, we disrupted SMAD4 in the visceral endoderm and epiblast, respectively, using a Cre-loxP mediated approach. We showed that mutant embryos lack of SMAD4 in the visceral endoderm (Smad4Co/Co;TTR-Cre) died at E7.5-E9.5 without head-fold and anterior embryonic structures. We demonstrated that TGF-β regulates expression of several genes, such as Hex1, Cer1, and Lim1, in the anterior visceral endoderm (AVE), and the failure of anterior embryonic development in Smad4Co/Co;TTR-Cre embryos is accompanied by diminished expression of these genes. Consistent with this finding, SMAD4-deficient embryoid bodies showed impaired responsiveness to TGF-β-induced gene expression and morphological changes. On the other hand, embryos carrying Cre-loxP mediated disruption of SMAD4 in the epiblasts exhibited relatively normal mesoderm and head-fold induction although they all displayed profound patterning defects in the later stages of gastrulation. Cumulatively, our data indicate that SMAD4 signaling in the epiblasts is dispensable for mesoderm induction although it remains critical for head patterning, which is significantly different from SMAD4 signaling in the AVE, where it specifies anterior embryonic patterning and head induction.
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Affiliation(s)
- Cuiling Li
- Mammalian Genetics Section, Genetics of Development and Disease Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10/9N105, 10 Center Drive, Bethesda, MD 20892, USA
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3
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Zou Z, Ocaya PA, Sun H, Kuhnert F, Stuhlmann H. Targeted Vezf1-null mutation impairs vascular structure formation during embryonic stem cell differentiation. Arterioscler Thromb Vasc Biol 2010; 30:1378-88. [PMID: 20431070 DOI: 10.1161/atvbaha.109.200428] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Vezf1 encodes an early zinc finger transcription factor that is essential for normal vascular development and functions in a dose-dependent manner. Here, we investigated the role of Vezf1 during processes of endothelial cell differentiation and maturation by studying mutant Vezf1 embryonic stem (ES) cells using the in vitro embryoid body differentiation model and the in vivo teratocarcinoma model. METHODS AND RESULTS Vezf1-/- ES cell-derived embryoid bodies failed to form a well-organized vascular network and showed dramatic vascular sprouting defects. Our results indicate that the retinol pathway is an important mediator of Vezf1 function and that loss of Vezf1 results in reduced retinol/vitamin A signaling and aberrant extracellular matrix (ECM) formation. Unexpectedly, we also uncovered defects during in vitro differentiation of Vezf1-/- ES cells along hematopoietic cell lineages. Vezf1-/- ES cell-derived teratocarcinomas were able to spontaneously differentiate into cell types of all 3 germ layers. However, histological and immunohistochemical examination of these tumors showed decreased cell proliferation, delayed differentiation, and large foci of cells with extensive deposition of ECM. Embryoid bodies and teratocarcinomas derived from heterozygous ES cells displayed an intermediate phenotype. CONCLUSIONS Together, these results suggest that Vezf1 is involved in early differentiation processes of the vasculature by regulating cell differentiation, proliferation, and ECM distribution and deposition.
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Affiliation(s)
- Zhongmin Zou
- Department of Cell Biology, Scripps Research Institute, La Jolla, CA, USA
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4
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Wang C, Faloon PW, Tan Z, Lv Y, Zhang P, Ge Y, Deng H, Xiong JW. Mouse lysocardiolipin acyltransferase controls the development of hematopoietic and endothelial lineages during in vitro embryonic stem-cell differentiation. Blood 2007; 110:3601-9. [PMID: 17675553 PMCID: PMC2077310 DOI: 10.1182/blood-2007-04-086827] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The blast colony-forming cell (BL-CFC) was identified as an equivalent to the hemangioblast during in vitro embryonic stem (ES) cell differentiation. However, the molecular mechanisms underlying the generation of the BL-CFC remain largely unknown. Here we report the isolation of mouse lysocardiolipin acyltransferase (Lycat) based on homology to zebrafish lycat, a candidate gene for the cloche locus. Mouse Lycat is expressed in hematopoietic organs and is enriched in the Lin(-)C-Kit(+)Sca-1(+) hematopoietic stem cells in bone marrow and in the Flk1(+)/hCD4(+)(Scl(+)) hemangioblast population in embryoid bodies. The forced Lycat transgene leads to increased messenger RNA expression of hematopoietic and endothelial genes as well as increased blast colonies and their progenies, endothelial and hematopoietic lineages. The Lycat small interfering RNA transgene leads to a decrease expression of hematopoietic and endothelial genes. An unbiased genomewide microarray analysis further substantiates that the forced Lycat transgene specifically up-regulates a set of genes related to hemangioblasts and hematopoietic and endothelial lineages. Therefore, mouse Lycat plays an important role in the early specification of hematopoietic and endothelial cells, probably acting at the level of the hemangioblast.
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Affiliation(s)
- Chengyan Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
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5
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Campagnolo L, Leahy A, Chitnis S, Koschnick S, Fitch MJ, Fallon JT, Loskutoff D, Taubman MB, Stuhlmann H. EGFL7 is a chemoattractant for endothelial cells and is up-regulated in angiogenesis and arterial injury. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 167:275-84. [PMID: 15972971 PMCID: PMC1451775 DOI: 10.1016/s0002-9440(10)62972-0] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The endothelium of the adult vasculature is normally quiescent, with the exception of the vasculature of the female reproductive system. However, in response to appropriate stimuli (ie, wound healing, atherosclerosis, tumor growth and metastasis, arthritis) the vasculature becomes activated and grows new capillaries through angiogenesis. We have recently identified a novel endothelial-restricted gene, Egfl7, that encodes a 41-kd secreted protein (Fitch MJ, Campagnolo L, Kuhnert F, Stuhlmann H: Egfl7, a novel epidermal growth factor-domain gene expressed in endothelial cells. Dev Dyn 2004, 230:316-324). Egfl7 is expressed at high levels early during mouse embryonic development and is strictly associated with the vascular bed. In this study, we investigated Egfl7 expression in the quiescent adult vasculature, in the pregnant uterus, and in two different models of arterial injury, namely ballooning and ferric chloride injury. By RNA in situ hybridization, Egfl7 expression in the vasculature was found to be restricted to the endothelium of the capillaries and mature vessels. In the pregnant uterus, increased vascularization was accompanied by up-regulation of Egfl7. On arterial injury, Egfl7 expression was up-regulated in the regenerating endothelium, but not in the neointima. Importantly, the EGFL7 protein acted as a chemoattractant for embryonic endothelial cells and fibroblasts in a cell migration assay. Together, these results suggest that Egfl7 functions in the formation and maintenance of endothelial integrity and that its up-regulation may be a critical component in the reorganization of the vascular bed in response to angiogenic stimuli.
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Affiliation(s)
- Luisa Campagnolo
- Division of Vascular Biology, Department of Cell Biology, The Scripps Research Institute, Mail CVN-26, 10550 North Torrey Pines Rd., La Jolla, CA 92037, USA
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6
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Niimi M, Kim MY, Tao L, Liu H, Wu X, Kambayashi JI, Yoshitake M, Sun B. Single embryonic stem cell-derived embryoid bodies for gene screening. Biotechniques 2005; 38:349-50, 352. [PMID: 15786800 DOI: 10.2144/05383bm01] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Masashi Niimi
- Otsuka Maryland Medicinal Laboratories, LLC, Rockville, MD 20850, USA
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7
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Fitch MJ, Campagnolo L, Kuhnert F, Stuhlmann H. Egfl7, a novel epidermal growth factor-domain gene expressed in endothelial cells. Dev Dyn 2005; 230:316-24. [PMID: 15162510 PMCID: PMC1458501 DOI: 10.1002/dvdy.20063] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We report the cloning and characterization of a novel epidermal growth factor (EGF) domain gene that was identified in a retroviral gene entrapment screen and is expressed in endothelial cells. This gene encodes a protein of 278 amino acids with an amino-terminal signal peptide and two centrally located EGF-like domains. We have named this novel gene in accordance with the guidelines of the Mouse Genome Informatics group Egfl7, for EGF-like domain 7. Egfl7 mRNA is expressed in highly vascularized adult tissues such as the lung, heart, uterus, and ovary. In addition, Egfl7 is expressed early during mouse embryogenesis and in undifferentiated murine embryonic stem cells. The analysis of Egfl7 expression in embryonic day 9.5 embryos by in situ hybridization indicates that Egfl7 is expressed in vascular structures in both the embryo proper and the yolk sac and at sites of mesodermal precursors of angioblasts. Within the cell, EGFL7 protein is localized to the endoplasmic reticulum and Golgi apparatus, suggesting that the protein is targeted for secretion. Indeed, recombinant EGFL7 is readily detectable in the supernatant media of transiently transfected HEK293 cells. We also report the identification of an Egfl7 paralog, Egfl8, and show that EGFL8 protein shares similar domains and molecular weight with EGFL7.
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Affiliation(s)
- Michael J Fitch
- Department of Cell Biology, Division of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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8
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Affiliation(s)
- Heidi Stuhlmann
- Department of Cell Biology, Division of Vascular Biology, Scripps Research Institute, Mail CVN-26, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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9
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Kuhnert F, Stuhlmann H. Identifying early vascular genes through gene trapping in mouse embryonic stem cells. Curr Top Dev Biol 2004; 62:261-81. [PMID: 15522745 DOI: 10.1016/s0070-2153(04)62009-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Frank Kuhnert
- Department of Cell Biology, Division of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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10
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Kearney JB, Bautch VL. In Vitro Differentiation of Mouse ES Cells: Hematopoietic and Vascular Development. Methods Enzymol 2003; 365:83-98. [PMID: 14696339 DOI: 10.1016/s0076-6879(03)65006-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Joseph B Kearney
- Program in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, CB#3280, Chapel Hill, North Carolina 27599, USA
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11
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Jackson M, Baird JW, Cambray N, Ansell JD, Forrester LM, Graham GJ. Cloning and characterization of Ehox, a novel homeobox gene essential for embryonic stem cell differentiation. J Biol Chem 2002; 277:38683-92. [PMID: 12087094 DOI: 10.1074/jbc.m203459200] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report here the identification and characterization of a novel paired-like homeobox-containing gene (Ehox). This gene, identified in embryonic stem (ES) cells, is differentially expressed during in vitro ES cell differentiation. We have assessed Ehox function using the ES cell in vitro differentiation system. This has involved molecular and biological analyses of the effects of sense or antisense Ehox expression (using episomal vectors) on ES cell differentiation. Analysis of antisense Ehox-expressing ES cells indicates that they are unable to express marker genes associated with hematopoietic, endothelial, or cardiac differentiation following removal of leukemia inhibitory factor. In contrast, overexpression of Ehox using the sense construct accelerated the appearance of these differentiation markers. ES cell self-renewal and differentiation assays reveal that inhibition of Ehox activity results in the maintenance of a stem cell phenotype in limiting concentrations of leukemia inhibitory factor and the almost complete impairment of the cardiomyocyte differentiation capacity of these cells. We therefore conclude that Ehox is a novel homeobox-containing gene that is essential for the earliest stages of murine ES cell differentiation.
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Affiliation(s)
- Melany Jackson
- John Hughes Bennett Laboratories, Department of Oncology, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, Scotland, United Kingdom
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12
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Carroll P, Renoncourt Y, Gayet O, De Bovis B, Alonso S. Sorting nexin-14, a gene expressed in motoneurons trapped by an in vitro preselection method. Dev Dyn 2001; 221:431-42. [PMID: 11500980 DOI: 10.1002/dvdy.1163] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A gene-trap strategy was set up in embryonic stem (ES) cells with the aim of trapping genes expressed in restricted neuronal lineages. The vector used trap genes irrespective of their activity in undifferentiated totipotent ES cells. Clones were subjected individually to differentiation in a system in which ES cells differentiated into neurons. Two ES clones in which the trapped gene was expressed in ES-derived neurons were studied in detail. The corresponding cDNAs were cloned, sequenced, and analysed by in situ hybridisation on wild-type embryo sections. Both genes are expressed in the nervous system. One gene, YR-23, encodes a large intracellular protein of unknown function. The second clone, YR-14, represents a sorting nexin (SNX14) gene whose expression in vivo coincides with that of LIM-homeodomain Islet-1 in several tissues. Sorting nexins are proteins associated with the endoplasmic reticulum (ER) and may play a role in receptor trafficking. Gene trapping followed by screening based on in vitro preselection of differentiated ES recombinant clones, therefore, has the potential to identify integration events in subsets of genes before generation of mouse mutants.
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MESH Headings
- Animals
- Base Sequence
- Carrier Proteins/biosynthesis
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Differentiation
- Cells, Cultured
- Cloning, Molecular
- DNA, Complementary/metabolism
- Databases, Factual
- Digoxigenin/pharmacology
- Electroporation
- Embryo, Mammalian/metabolism
- Endoplasmic Reticulum/metabolism
- Exons
- Galactosides/metabolism
- Gene Expression Regulation, Developmental
- Genetic Techniques
- Genetic Vectors
- In Situ Hybridization
- Indoles/metabolism
- Introns
- Lac Operon
- Mice
- Models, Genetic
- Molecular Sequence Data
- Motor Neurons/metabolism
- Nervous System/embryology
- Neurons/metabolism
- Protein Structure, Tertiary
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Sorting Nexins
- Stem Cells/metabolism
- Time Factors
- Vesicular Transport Proteins
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Affiliation(s)
- P Carroll
- INSERM U.382, Developmental Biology Institute of Marseille (IBDM), CNRS/INSERM/Université de la Méditerranée/AP de Marseille, Campus de Luminy, Marseille, France
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13
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Skarnes WC. Gene trapping methods for the identification and functional analysis of cell surface proteins in mice. Methods Enzymol 2001; 328:592-615. [PMID: 11075368 DOI: 10.1016/s0076-6879(00)28420-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- W C Skarnes
- Department of Molecular and Cell Biology, University of California at Berkeley 94720-3200, USA
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14
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Abstract
New methods enable the identification of compounds that both induce a specific cellular state and lead to identification of proteins that regulate that state. Together, developments in three critical areas: chemical diversity, phenotype-based screening and target identification, enable the systematic application of this chemical genetic approach to almost any biological problem or disease process.
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Affiliation(s)
- B R Stockwell
- Whitehead Institute for Biomedical Research, Nine Cambridge Center, MA 02142, USA.
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15
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Xiong JW, Leahy A, Stuhlmann H. Retroviral promoter-trap insertion into a novel mammalian septin gene expressed during mouse neuronal development. Mech Dev 1999; 86:183-91. [PMID: 10446280 DOI: 10.1016/s0925-4773(99)00113-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We have characterized a retroviral promoter-trap insertion into a novel mammalian septin gene, Sep3. Its predicted amino acid sequence shares significant homology to that of Saccharomyces cerevisiae CDC3, CDC10, CDC11, CDC12, the Drosophila genes Pnut, Sep1, Sep2, and the mammalian genes BH5, CDC10, Nedd5, Diff6, and Sep2, which are implicated in cytokinesis and cell polarity. Sep3 encodes a protein of 465 amino acids, and contains an evolutionary conserved ATP/GTP-binding motif, two coiled-coil domains, and a highly hydrophobic domain at the C terminus. Alkaline phosphatase reporter gene expression in transgenic embryos was first detected at E8.5 in the neural fold, and high levels of expression continued throughout embryogenesis in the neural tube and brain. In addition, a low level of transient expression was detected in the somites, gut, and branchial arches of mouse embryos. Overall, reporter gene expression recapitulated Sep3 mRNA expression during mouse embryogenesis. In adults, Sep3 transcripts were only detected in the brain and testis. Zoo blot analysis revealed that Sep3-related sequences exist in several vertebrate species including zebrafish, frog, chicken, mouse and human. Consistent with the retroviral insertion into the 3' UTR of the Sep3 gene, no obvious phenotypes associated with the promoter trap were detected in transgenic embryos or adult mice. In summary, we report the first isolation of a novel full-length Sep3 cDNA and extensive characterization of its expression during mouse embryogenesis and in adult tissues.
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Affiliation(s)
- J W Xiong
- Department of Biochemistry and Molecular Biology, Mount Sinai School of Medicine, New York, NY 10029, USA
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Leahy A, Xiong JW, Kuhnert F, Stuhlmann H. Use of developmental marker genes to define temporal and spatial patterns of differentiation during embryoid body formation. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1999; 284:67-81. [PMID: 10368935 DOI: 10.1002/(sici)1097-010x(19990615)284:1<67::aid-jez10>3.0.co;2-o] [Citation(s) in RCA: 165] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mouse embryonic stem cells are pluripotent cells that are derived from the inner cell mass of blastocysts. When induced to synchronously enter a program of differentiation in vitro, they form embryoid bodies that contain cells of the mesodermal, hematopoietic, endothelial, muscle, and neuronal lineages. Here, we used a panel of marker genes with early expression within the germ layers (oct-3, Brachyury T, Fgf-5, nodal, and GATA-4) or a variety of lineages (flk-1, Nkx-2.5, EKLF, and Msx3) to determine how progressive differentiation of embryoid bodies in culture correlated with early postimplantation development of mouse embryos. Using RNA in situ hybridization, we found that the temporal and spatial relationships existing between these marker genes in vivo were maintained also in vitro. Studying the onset of marker gene expression allowed us also to determine the time course of differentiation during the formation of embryoid bodies. Thus, stages equivalent to embryogenesis between implantation and the beginning of gastrulation (4.5-6.5 d.p.c.) occur within the first two days of embryoid body differentiation. Between days 3 and 5, embryoid bodies contain cell lineages found in embryos during gastrulation at 6.5 to 7.0 d.p.c., and after day 6 in culture, embryoid bodies are equivalent to early organogenesis-stage embryos (7.5 d.p.c.). In addition, we demonstrate that the panel of developmental markers can be applied in a screen for stage- or lineage-specific genes. Reporter gene expression from entrapment vector insertions can be co-localized with expression of specific markers within the same cell during embryoid body formation as well as during embryogenesis. Our results thus demonstrate the power of embryoid body formation as an in vitro model system to study early lineage determination and organogenesis in mammals, and indicate that they will prove to be useful tools for identifying developmental genes whose expression is restricted to particular lineages.
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Affiliation(s)
- A Leahy
- Brookdale Center for Developmental and Molecular Biology, Mount Sinai School of Medicine, New York, New York 10029, USA
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17
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Xiong JW, Leahy A, Lee HH, Stuhlmann H. Vezf1: A Zn finger transcription factor restricted to endothelial cells and their precursors. Dev Biol 1999; 206:123-41. [PMID: 9986727 DOI: 10.1006/dbio.1998.9144] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Using retroviral entrapment vectors, we identified a novel mouse gene whose expression is restricted to vascular endothelial cells and their precursors in the yolk sac blood islands. A 3.68-kb cDNA corresponding to the endogenous transcript was isolated using genomic DNA flanking the entrapment vector insertion as a probe. We have named this gene Vezf1 for vascular endothelial zinc finger 1. Vezf1 encodes a protein with a predicted molecular mass of 56 kDa and that contains six putative zinc finger domains and shows high homology to a previously identified human gene, DB1, that is believed to be involved in regulating expression of cytokine genes such as interleukin-3. In situ hybridization analysis revealed the onset of expression in advanced primitive streak-stage embryos being located in the extraembryonic mesodermal component of the visceral yolk sac and in the anteriormost mesoderm of the embryo proper. During head-fold and somite stages, expression was restricted to vascular endothelial cells that arise during both vasculogenesis and angiogenesis. Vezf1-related sequences were found to be highly conserved among higher vertebrate species that have acquired extraembryonic yolk sac membranes during evolution. The Vezf1 locus mapped to the proximal part of mouse chromosome 2, a region which has homology to human chromosome 9q. Vezf1 expression correlates temporally and spatially with the early differentiation of angioblasts into the endothelial cell lineage and the proliferation of endothelial cells of the embryonic vascular system. Thus, Vezf1 may play an important role in the endothelial lineage determination and may have an additional role during later stages of embryonic vasculogenesis and angiogenesis.
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Affiliation(s)
- J W Xiong
- Brookdale Center for Developmental and Molecular Biology, Mount Sinai School of Medicine, New York, New York, 10029, USA
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18
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Stockwell BR, Haggarty SJ, Schreiber SL. High-throughput screening of small molecules in miniaturized mammalian cell-based assays involving post-translational modifications. CHEMISTRY & BIOLOGY 1999; 6:71-83. [PMID: 10021420 DOI: 10.1016/s1074-5521(99)80004-0] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Fully adapting a forward genetic approach to mammalian systems requires efficient methods to alter systematically gene products without prior knowledge of gene sequences, while allowing for the subsequent characterization of these alterations. Ideally, these methods would also allow function to be altered in a temporally controlled manner. RESULTS We report the development of a miniaturized cell-based assay format that enables a genetic-like approach to understanding cellular pathways in mammalian systems using small molecules, rather than mutations, as the source of gene-product alterations. This whole-cell immunodetection assay can sensitively detect changes in specific cellular macromolecules in high-density arrays of mammalian cells. Furthermore, it is compatible with screening large numbers of small molecules in nanoliter to microliter culture volumes. We refer to this assay format as a 'cytoblot', and demonstrate the use of cytoblotting to monitor biosynthetic processes such as DNA synthesis, and post-translational processes such as acetylation and phosphorylation. Finally, we demonstrate the applicability of these assays to natural-product screening through the identification of marine sponge extracts exhibiting genotype-specific inhibition of 5-bromodeoxyuridine incorporation and suppression of the anti-proliferative effect of rapamycin. CONCLUSIONS We show that cytoblots can be used for high-throughput screening of small molecules in cell-based assays. Together with small-molecule libraries, the cytoblot assay can be used to perform chemical genetic screens analogous to those used in classical genetics and thus should be applicable to understanding a wide variety of cellular processes, especially those involving post-transitional modifications.
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Affiliation(s)
- B R Stockwell
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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