scholarly journals Identification of a Mouse Homolog of the Human BTEB2Transcription Factor as a β-Catenin-Independent Wnt-1-Responsive Gene

2001 ◽  
Vol 21 (2) ◽  
pp. 562-574 ◽  
Author(s):  
Lisa Taneyhill Ziemer ◽  
Diane Pennica ◽  
Arnold J. Levine
Keyword(s):  
Cell Line ◽  
Cell Fate ◽  
Target Genes ◽  
Wild Type Mouse ◽  
Subtractive Hybridization ◽  
Parental Cell ◽  
Mammary Tissue ◽  
Parental Cell Line ◽  
Mouse Homolog ◽  
Downstream Target

ABSTRACT The Wnt/Wg signaling pathway functions during development to regulate cell fate determination and patterning in various organisms. Two pathways are reported to lie downstream of Wnt signaling in vertebrates. The canonical pathway relies on the activation of target genes through the β-catenin–Lef/TCF complex, while the noncanonical pathway employs the activation of protein kinase C (PKC) and increases in intracellular calcium to induce target gene expression. cDNA subtractive hybridization between a cell line that overexpresses Wnt-1 (C57MG/Wnt-1) and the parental cell line (C57MG) was performed to identify downstream target genes of Wnt-1 signaling. Among the putative Wnt-1 target genes, we have identified a mouse homolog of the gene encoding human transcription factor basic transcription element binding protein 2 (mBTEB2). ThemBTEB2 transcript is found at high levels in mammary tissue taken from a transgenic mouse overexpressing Wnt-1 (both tissue prior to active proliferation and tumor tissue) but is barely detectable in wild-type mouse mammary glands. The regulation of mBTEB2 by Wnt-1 signaling in tissue culture occurs through a β-catenin–Lef/TCF-independent mechanism, as it is instead partially regulated by PKC. The Wnt-1-induced, PKC-dependent activation of mouse BTEB2 in C57MG cells, as well as the ability of Wnt-1 to stabilize β-catenin in these cells, is consistent with the hypothesis that both the noncanonical and canonical Wnt pathways are activated concomitantly in the same cell. These results suggest that mBTEB2 is a biologically relevant target of Wnt-1 signaling that is activated through a β-catenin-independent, PKC-sensitive pathway in response to Wnt-1.

PU.1 Activity Determines Fate of Myeloid Progenitor Cells during Lineage Commitment.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4207-4207
Author(s):  
Vitek Pospisil ◽  
Emanuel Necas ◽  
Tomas Stopka
Keyword(s):  
Cell Line ◽  
Progenitor Cell ◽  
Target Genes ◽  
Myeloid Cell ◽  
Erythroid Differentiation ◽  
Parental Cell ◽  
Cell Populations ◽  
Parental Cell Line ◽  
Mrna Levels ◽  
Cell Commitment

Abstract Myeloid cell commitment is regulated by factors interacting with chromatin in a progenitor cell entering differentiation. PU.1 is an ETS family transcription factor that has been well characterized in inducing myelopoiesis and blocking erythroid differentiation. Conditionally activated PU.1-Estrogen Receptor transgene in mouse PU.1 knockout-derived hematopoietic progenitors is known to induce macrophage differentiation. We observed that manipulation of PU.1 activity by using different levels of PU.1-ER activator, tamoxifen, was capable of producing major populations of myeloid progeny including macrophages, granulocytes, lymphocytes and mastocytes. Gradual activation of PU.1 produce distinct committed populations that require presence of PU.1 activator. Withdrawal of tamoxifen from macrophages restored cycling and pluripotent potential resembling parental cell line. Furthermore, very low PU.1 activity induced frequent chromosomal aberations such as polyploidy. To determine that PU.1 directly caused these phenotypic changes we determined its occupancy at genes representing PU.1 targets by quantitative chromatin immunoprecipitation (ChIP). We demonstrate that PU.1 is enriched at regulatory regions of lineage restricted cell populations including promoters of CD11b, CD14, IL7R, PAX5, RAG1, Gelatinase, Lysozyme, and MCP. Different PU.1 levels promote distinct cell populations that have different localizations of PU.1 in chromatin. We also tested mRNA levels of PU.1 target genes in progenitor cell line induced by PU.1. Macrophage-specific target genes such as CD11b and CD14 are induced at high PU.1 levels and granulocytic PU.1 targets such as Gelatinase and Lysozyme are induced at intermediate and high PU.1 levels. B-cell specific mRNAs such as IL7-R, PAX5, and RAG1 were induced at low and high PU.1 levels. Our data suggest that PU.1 is recruited to and transactivates its lineage-restricted target genes differently at distinct PU.1 levels and such mechanism may be involved in myeloid cell commitment and leukemogenesis.

The Cisplatin, 5-fluorouracil, Irinotecan, and Gemcitabine Treatment in Resistant 2D and 3D Model Triple Negative Breast Cancer Cell Line: ABCG2 Expression Data

2021 ◽  
Vol 21 ◽  
Author(s):  
Fatma Kubra Ata ◽  
Serap Yalcin
Keyword(s):  
Breast Cancer ◽  
Cell Culture ◽  
Cell Line ◽  
Cell Lines ◽  
Expression Profile ◽  
Three Dimensional ◽  
Parental Cell ◽  
Parental Cell Line ◽  
Xtt Assay ◽  
Gene And Protein Expression

Background: Chemotherapeutics have been commonly used in cancer treatment. Objective: In this study, the effects of Cisplatin, 5-fluorouracil, Irinotecan, and Gemcitabine have been evaluated on two-dimensional (2D) (sensitive and resistance) cell lines and three dimensional (3D) spheroid structure of MDA-MB-231. The 2D cell culture lacks a natural tissue-like structural so, using 3D cell culture has an important role in the development of effective drug testing models. Furthermore, we analyzed the ATP Binding Cassette Subfamily G Member 2 (ABCG2) gene and protein expression profile in this study. We aimed to establish a 3D breast cancer model that can mimic the in vivo 3D breast cancer microenvironment. Methods: The 3D spheroid structures were multiplied (globally) using the three-dimensional hanging drop method. The cultures of the parental cell line MDA-MB-231 served as the controls. After adding the drugs in different amounts we observed a clear and well-differentiated spheroid formation for 24 h. The viability and proliferation capacity of 2D (sensitive and resistant) cell lines and 3D spheroid cell treatment were assessed by the XTT assay. Results: Cisplatin, Irinotecan, 5-Fu, and Gemcitabine-resistant MDA-MB-231 cells were observed to begin to disintegrate in a three-dimensional clustered structure at 24 hours. Additionally, RT-PCR and protein assay showed overexpression of ABCG2 when compared to the parental cell line. Moreover, MDA-MB-231 cells grown in 3D showed decreased sensitivity to chemotherapeutics treatment. Conclusion: More resistance to chemotherapeutics and altered gene expression profile was shown in 3D cell cultures when compared with the 2D cells. These results might play an important role to evaluate the efficacy of anticancer drugs, explore mechanisms of MDR in the 3D spheroid forms.

Energy deprivation and a deficiency in downstream metabolic target genes during the onset of embryonic heart failure in RXRalpha−/− embryos

Development ◽  
1998 ◽  
Vol 125 (3) ◽  
pp. 533-544 ◽  
Author(s):  
P. Ruiz-Lozano ◽  
S.M. Smith ◽  
G. Perkins ◽  
S.W. Kubalak ◽  
G.R. Boss ◽  
...  
Keyword(s):  
Target Genes ◽  
Subtractive Hybridization ◽  
Causative Factor ◽  
Mutant Mice ◽  
Intermediary Metabolism ◽  
Wild Type ◽  
Energy Deficiency ◽  
Downstream Target ◽  
Ultrastructural Studies ◽  
Energy Deprivation

RXRalpha null mutant mice display ocular and cardiac malformations, liver developmental delay, and die from cardiac failure around embryonic day (E) 14.5 pc. To dissect the molecular basis of the RXRalpha-associated cardiomyopathy, we performed subtractive hybridization and systematically characterized putative downstream target genes that were selectively lacking in the mutant embryos, both at early (E10.5) and late (E13.5) stages of mouse embryonic development. Approximately 50% of the subtracted clones (61/115) encoded proteins involved in intermediary metabolism and electron transport, suggesting an energy deficiency in the RXRalpha−/− embryos. In particular, clone G1, which encodes subunit 14.5b of the NADH-ubiquinone dehydrogenase complex, displayed a dose-dependent expression in the wild-type, heterozygous and RXRalpha mutant mice. This gene was also downregulated in a retinoid-deficient rat embryo model. ATP content and medium Acyl-CoA dehydrogenase mRNA were lower in RXRalpha mutant hearts compared to wild-type mice. Ultrastructural studies showed that the density of mitochondria per myocyte was higher in the RXRalpha mutant compared to wild-type littermates. We propose a model whereby defects in intermediary metabolism may be a causative factor of the RXRalpha−/− phenotype and resembles an embryonic form of dilated cardiomyopathy.

Control of thymidylate synthase mRNA content and gene transcription in an overproducing mouse cell line

1985 ◽  
Vol 5 (10) ◽  
pp. 2527-2532
Author(s):  
C H Jenh ◽  
P K Geyer ◽  
L F Johnson
Keyword(s):  
Cell Line ◽  
Thymidylate Synthase ◽  
Northern Blot Analysis ◽  
Mouse Cell ◽  
Parental Cell ◽  
S Phase ◽  
Parental Cell Line ◽  
Mouse Cell Line ◽  
Isolated Nuclei ◽  
Mrna Content

We studied the content and metabolism of thymidylate synthase mRNA in cultured mouse fibroblasts that were undergoing a serum-induced transition from the resting to growing state. The studies were performed with a 5-fluorodeoxyuridine-resistant 3T6 cell line (LU3-7) that over produces the enzyme and its mRNA about 50-fold and that regulates the expression of the thymidylate synthase gene in the same manner as the parental cell line. We have previously shown that the rate of synthesis of thymidylate synthase increases at least ninefold when the serum-stimulated cells traverse the S phase. Here we show, by Northern blot analysis, that thymidylate synthase mRNA increased 20- to 40-fold as cells progressed from resting to late S phase. About 85% of poly(A)+ thymidylate synthase mRNA was associated with polysomes at all times. The increase in thymidylate synthase poly(A)+ mRNA content was the result of an eightfold increase in the rate of production of this species, as shown by pulse-labeling studies. Pulse-chase analysis revealed that the half-life of thymidylate synthase poly(A)+ mRNA was similar in resting (9 h) and growing (7 h) cells. The rate of transcription of the thymidylate synthase gene, as determined in isolated nuclei, increased only by a factor of three to four during the S phase. Since the content of the message increased to a much greater extent than the rate of transcription of the gene, posttranscriptional controls must also play a role in regulating the content of thymidylate synthase mRNA under these conditions. Our results suggest that the cell may regulate the distribution of thymidylate synthase mRNA between a relatively stable poly(A)+ RNA species and a labile poly(A)- RNA species.

scholarly journals Amplicon structure in multidrug-resistant murine cells: a nonrearranged region of genomic DNA corresponding to large circular DNA.

1992 ◽  
Vol 12 (3) ◽  
pp. 1179-1187 ◽  
Author(s):  
F Ståhl ◽  
Y Wettergren ◽  
G Levan
Keyword(s):  
Tumor Cell ◽  
Cell Line ◽  
Single Unit ◽  
Parental Cell ◽  
Parental Cell Line ◽  
Mouse Tumor ◽  
Dna Molecules ◽  
Circular Dna ◽  
Double Minutes ◽  
Mdr Genes

Multidrug resistance (MDR) in tumor cell lines is frequently correlated with amplification of one or more mdr genes. Usually the amplified domain also includes several neighboring genes. Using pulsed-field gel electrophoresis, we have established a restriction map covering approximately 2,200 kb in the drug-sensitive mouse tumor cell line TC13K. The mapped region is located on mouse chromosome 5 and includes the three mdr genes, the gene for the calcium-binding sorcin protein, and a gene with unknown function designated class 5. Long-range maps of the amplified DNA sequences in five of six MDR sublines that had been independently derived from TC13K generally displayed the same pattern as did the parental cell line. All six MDR sublines exhibited numerous double minutes, and one of them displayed a homogeneously staining region in a subpopulation. Large circular molecules, most likely identical to one chromatid of the double minutes, were detected in four of the sublines by linearization with gamma irradiation. The size of the circles was about 2,500 kb, which correlated to a single unit of the amplified domain. We therefore propose that in four independent instances of MDR development, a single unit of about 2,500 kb has been amplified in the form of circular DNA molecules. The restriction enzyme map of the amplified unit is unchanged compared with that of the parental cell line, whereas the joining sites of the circular DNA molecules are not identical but are in the same region.

scholarly journals Control of thymidylate synthase mRNA content and gene transcription in an overproducing mouse cell line.

1985 ◽  
Vol 5 (10) ◽  
pp. 2527-2532 ◽  
Author(s):  
C H Jenh ◽  
P K Geyer ◽  
L F Johnson
Keyword(s):  
Cell Line ◽  
Thymidylate Synthase ◽  
Northern Blot Analysis ◽  
Mouse Cell ◽  
Parental Cell ◽  
S Phase ◽  
Parental Cell Line ◽  
Mouse Cell Line ◽  
Isolated Nuclei ◽  
Mrna Content

We studied the content and metabolism of thymidylate synthase mRNA in cultured mouse fibroblasts that were undergoing a serum-induced transition from the resting to growing state. The studies were performed with a 5-fluorodeoxyuridine-resistant 3T6 cell line (LU3-7) that over produces the enzyme and its mRNA about 50-fold and that regulates the expression of the thymidylate synthase gene in the same manner as the parental cell line. We have previously shown that the rate of synthesis of thymidylate synthase increases at least ninefold when the serum-stimulated cells traverse the S phase. Here we show, by Northern blot analysis, that thymidylate synthase mRNA increased 20- to 40-fold as cells progressed from resting to late S phase. About 85% of poly(A)+ thymidylate synthase mRNA was associated with polysomes at all times. The increase in thymidylate synthase poly(A)+ mRNA content was the result of an eightfold increase in the rate of production of this species, as shown by pulse-labeling studies. Pulse-chase analysis revealed that the half-life of thymidylate synthase poly(A)+ mRNA was similar in resting (9 h) and growing (7 h) cells. The rate of transcription of the thymidylate synthase gene, as determined in isolated nuclei, increased only by a factor of three to four during the S phase. Since the content of the message increased to a much greater extent than the rate of transcription of the gene, posttranscriptional controls must also play a role in regulating the content of thymidylate synthase mRNA under these conditions. Our results suggest that the cell may regulate the distribution of thymidylate synthase mRNA between a relatively stable poly(A)+ RNA species and a labile poly(A)- RNA species.

A Novel Microarray Gene Expression Analysis of Murine AML Cell Lines Provides Clues to the Development of Drug Resistance to Ara-C

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5017-5017
Author(s):  
Susan K Rathe ◽  
David Largaespada
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
Cell Lines ◽  
Ribosomal Subunit ◽  
Nuclear Factor Κb ◽  
Parental Cell ◽  
Parental Cell Line ◽  
Drug Resistant ◽  
Microarray Gene Expression ◽  
Expression Microarrays

Abstract Acute myeloid leukemia (AML) has the ability to evade cell death in the presence of chemotherapeutic cocktails containing cytosine arabinoside (Ara-C). This lab previously developed two highly resistant murine AML cell lines, B117H and B140H, by introducing increasing concentrations of Ara-C to their parental cell lines, B117P and B140P, respectively. B117H and B140H can tolerate Ara-C concentrations ~1000X that of their drug sensitive parental cell lines. mRNA from all four cell lines were used in gene expression microarrays for the purpose of comparing Ara-C drug resistant murine AML cell lines with their Ara-C drug sensitive parental lines. A novel algorithm was developed to evaluate the changes in gene expression between the drug resistant and drug sensitive cells. The algorithm differed from more conventional algorithms in two key ways. First, the detection data was normalized by using ribosomal subunit 9 (Rsp9) as the normalization gene, and secondly it calculated fold change by comparing the minimum value of one population to the maximum value of the other population. The output of this algorithm was a list of genes with significant gene expression changes. These genes were next submitted to the Ingenuity Pathway Analysis (IPA) process. IPA implicated nuclear factor-κB (NFκB) in the Ara-C resistance process. Cell growth assays confirmed that the Ara-C drug resistant B117H cell line was significantly more sensitive to NFκB inhibition than its Ara-C sensitive parental cell line. This leads us to believe that the selection of Ara-C resistance may also concomitantly make some AML cells highly sensitive to killing by NFκB inhibition. This theory is being tested further through the use of drug combination assays, to determine if a synergistic or antagonistic relationship exists between Ara-C and various drugs that affect the NFκB pathway.

scholarly journals Antagonistic BMP–cWNT signaling in the cnidarian Nematostella vectensis reveals insight into the evolution of mesoderm

2017 ◽  
Vol 114 (28) ◽  
pp. E5608-E5615 ◽  
Author(s):  
Naveen Wijesena ◽  
David K. Simmons ◽  
Mark Q. Martindale
Keyword(s):  
Cell Fate ◽  
Target Genes ◽  
Bmp Signaling ◽  
Nematostella Vectensis ◽  
Beta Catenin ◽  
Molecular Signaling ◽  
Downstream Target ◽  
Evolutionary Innovation ◽  
Morphogenetic Protein ◽  
Cnidarian Nematostella Vectensis

Gastrulation was arguably the key evolutionary innovation that enabled metazoan diversification, leading to the formation of distinct germ layers and specialized tissues. Differential gene expression specifying cell fate is governed by the inputs of intracellular and/or extracellular signals. Beta-catenin/Tcf and the TGF-beta bone morphogenetic protein (BMP) provide critical molecular signaling inputs during germ layer specification in bilaterian metazoans, but there has been no direct experimental evidence for a specific role for BMP signaling during endomesoderm specification in the early branching metazoan Nematostella vectensis (an anthozoan cnidarian). Using forward transcriptomics, we show that beta-catenin/Tcf signaling and BMP2/4 signaling provide differential inputs into the cnidarian endomesodermal gene regulatory network (GRN) at the onset of gastrulation (24 h postfertilization) in N. vectensis. Surprisingly, beta-catenin/Tcf signaling and BMP2/4 signaling regulate a subset of common downstream target genes in the GRN in opposite ways, leading to the spatial and temporal differentiation of fields of cells in the developing embryo. Thus, we show that regulatory interactions between beta-catenin/Tcf signaling and BMP2/4 signaling are required for the specification and determination of different embryonic regions and the patterning of the oral–aboral axis in Nematostella. We also show functionally that the conserved “kernel” of the bilaterian heart mesoderm GRN is operational in N. vectensis, which reinforces the hypothesis that the endoderm and mesoderm in triploblastic bilaterians evolved from the bifunctional endomesoderm (gastrodermis) of a diploblastic ancestor, and that slow rhythmic contractions might have been one of the earliest functions of mesodermal tissue.

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