Other search tools

About this data

The publication data currently available has been vetted by Vanderbilt faculty, staff, administrators and trainees. The data itself is retrieved directly from NCBI's PubMed and is automatically updated on a weekly basis to ensure accuracy and completeness.

If you have any questions or comments, please contact us.

Results: 481 to 484 of 484

Publication Record

Connections

A central role for a single c-Myb binding site in a thymic locus control region.
Ess KC, Whitaker TL, Cost GJ, Witte DP, Hutton JJ, Aronow BJ
(1995) Mol Cell Biol 15: 5707-15
MeSH Terms: Adenosine Deaminase, Animals, Base Sequence, Binding Sites, Cell Line, Chromatin, Enhancer Elements, Genetic, Gene Expression Regulation, Developmental, Humans, Introns, Mice, Mice, Transgenic, Molecular Sequence Data, Point Mutation, Proto-Oncogene Proteins, Proto-Oncogene Proteins c-myb, Saccharomyces cerevisiae, T-Lymphocytes, Thymus Gland, Trans-Activators
Show Abstract · Added June 9, 2010
Locus control regions (LCRs) are powerful assemblies of cis elements that organize the actions of cell-type-specific trans-acting factors. A 2.3-kb LCR in the human adenosine deaminase (ADA) gene first intron, which controls expression in thymocytes, is composed of a 200-bp enhancer domain and extended flanking sequences that facilitate activation from within chromatin. Prior analyses have demonstrated that the enhancer contains a 28-bp core region and local adjacent augmentative cis elements. We now show that the core contains a single critical c-Myb binding site. In both transiently cotransfected human cells and stable chromatin-integrated yeast cells, c-Myb strongly transactivated reporter constructs that contained polymerized core sequences. c-Myb protein was strongly evident in T lymphoblasts in which the enhancer was active and was localized within discrete nuclear structures. Fetal murine thymus exhibited a striking concordance of endogenous c-myb expression with that of mouse ADA and human ADA LCR-directed transgene expression. Point mutation of the c-Myb site within the intact 2.3-kb LCR severely attenuated enhancer activity in transfections and LCR activity in transgenic thymocytes. Within the context of a complex enhancer and LCR, c-Myb can act as an organizer of thymocyte-specific gene expression via a single binding site.
0 Communities
1 Members
0 Resources
20 MeSH Terms
Autonomous endodermal determination in Xenopus: regulation of expression of the pancreatic gene XlHbox 8.
Gamer LW, Wright CV
(1995) Dev Biol 171: 240-51
MeSH Terms: Activins, Animals, Embryo, Nonmammalian, Endoderm, Gene Expression Regulation, Developmental, Genes, Homeobox, Homeodomain Proteins, Inhibins, Up-Regulation, Xenopus, Xenopus Proteins
Show Abstract · Added June 11, 2010
In neural plate stage Xenopus embryos, XlHbox 8 expression marks anterior endodermal cells fated to develop into pancreas/duodenum, and expression continues in adult pancreas in exocrine duct, acinar, and islet cells. Here, XlHbox 8 is used as a marker in experiments addressing the mechanisms of early endodermal patterning, particularly with respect to the role of specific polypeptide growth factors. When mesoderm-free vegetal explants (VEs) from early blastula stage embryos are cultured in isolation, XlHbox 8 expression develops autonomously in the dorsal region, strongly suggesting that endodermal region-specific determination occurs before MBT. Data from microinjection experiments using RNA encoding the activin and FGF dominant negative receptors and growth factor treatments of isolated VEs suggest that activin positively regulates XlHbox 8 expression, whereas bFGF is a potent negative regulator. Moreover, bFGF induces mesodermal marker expression in VEs. This suggests that the early endodermal determination state is plastic and that elevated levels of bFGF may convert vegetal (endodermal) cells into mesoderm. We propose a model for XlHbox 8 regulation in which an early signal from the Nieuwkoop center (whose eventual fate is endoderm) predisposes dorsovegetal cells for autonomous XlHbox 8 expression, in an area of high local activin (or activin-like) ligand concentration, and low relative concentrations of bFGF.
1 Communities
1 Members
0 Resources
11 MeSH Terms
pRb is necessary for inhibition of N-myc expression by TGF-beta 1 in embryonic lung organ cultures.
Serra R, Moses HL
(1995) Development 121: 3057-66
MeSH Terms: Animals, Antigens, Polyomavirus Transforming, Base Sequence, DNA Primers, Epithelium, Gene Expression Regulation, Developmental, In Situ Hybridization, Lung, Mice, Mice, Mutant Strains, Mice, Transgenic, Molecular Sequence Data, Morphogenesis, Organ Culture Techniques, Polymerase Chain Reaction, Proto-Oncogene Proteins c-myc, Retinoblastoma Protein, Transforming Growth Factor beta
Show Abstract · Added February 17, 2014
The beta type transforming growth factors (TGF-beta) are potent inhibitors of epithelial cell proliferation, and data suggest that growth inhibition by TGF-beta 1 is mediated through suppression of Myc family genes in certain cell types. Indirect evidence has indicated that the product of the retinoblastoma gene (pRb) may also be involved in this pathway. Previously, we have shown that TGF-beta 1 inhibits branching morphogenesis and N-myc expression in mouse embryonic lung cultures. The purpose of this study was to determine the role of pRb in the inhibition of branching morphogenesis and N-myc expression by TGF-beta 1. Treatment with TGF-beta 1 was shown to inhibit development of lungs from homozygous Rb null (Rb-/-) and heterozygous null (Rb+/-) mouse embryos to the same extent as lungs from wild-type (Rb+/+) embryos. However, TGF-beta 1 treatment did not suppress N-myc expression in Rb-/- as it did in Rb+/+ embryonic lung explants as determined by in situ hybridization and quantitative RT-PCR. The effect of TGF-beta 1 treatment on N-myc expression in lungs from Rb+/- embryos was intermediate between that seen in Rb+/+ and Rb-/- embryos. Embryonic lungs derived from transgenic mice expressing the SV40 large T-antigen in lung epithelium under the control of the surfactant protein C promoter also showed inhibition of development in response to TGF-beta 1 treatment. The data demonstrate that pRb is necessary for TGF-beta 1 suppression of N-myc expression but not for TGF-beta 1 inhibition of branching morphogenesis; therefore, suppression of N-myc is not necessary for inhibition of branching morphogenesis by TGF-beta 1.
0 Communities
1 Members
0 Resources
18 MeSH Terms
Cholesterol side-chain cleavage cytochrome P450 gene expression in the primitive gut of the mouse embryo does not require steroidogenic factor 1.
Keeney DS, Ikeda Y, Waterman MR, Parker KL
(1995) Mol Endocrinol 9: 1091-8
MeSH Terms: Animals, Base Sequence, Cholesterol Side-Chain Cleavage Enzyme, DNA Primers, DNA-Binding Proteins, Fushi Tarazu Transcription Factors, Gene Expression Regulation, Developmental, Gene Expression Regulation, Enzymologic, Homeodomain Proteins, In Situ Hybridization, Intestines, Mice, Mice, Transgenic, Molecular Sequence Data, Progesterone, RNA, Messenger, Receptors, Cytoplasmic and Nuclear, Skin, Steroidogenic Factor 1, Transcription Factors
Show Abstract · Added February 12, 2015
In situ hybridization studies reveal novel sites of expression of cholesterol side-chain cleavage cytochrome P450 (P450scc) during murine embryonic development. In addition to fetal adrenals and testes, P450scc transcripts localize in situ to the primitive gut and to a subset of unidentified cells in the dermal mesenchyme of embryonic skin. In the gut, transcripts are most abundant in luminal epithelia of the hindgut, which will form the colon. P450scc transcript abundance at these novel sites is a fraction of that in fetal adrenals or testes, suggesting a local rather than an endocrine function. Immunocytochemical analyses localize P450scc protein to the fetal hindgut, indicating that the transcripts are translated in vivo. RNA isolated from microdissected embryonic hindgut and skin was reverse transcribed and amplified by polymerase chain reaction. DNA sequence analyses of polymerase chain reaction products confirmed that specific hybridization in situ represents authentic P450scc gene (Cyp11A) transcripts and that 3 beta-hydroxysteroid dehydrogenase/delta 5-->delta 4-isomerase transcripts are also present, demonstrating the potential of these fetal tissues to produce pregnenolone and progesterone. P450scc transcripts are also detectable by in situ hybridization in primitive gut and skin of Fushi tarazu factor 1 null mice, which lack the nuclear receptor steroidogenic factor 1, proving that steroidogenic factor 1 is not required for steroid hydroxylase gene expression at these sites. The capacity for C21 steroid biosynthesis in primitive gut and skin during organogenesis raises the question whether local production of steroid hormones may be required for normal cellular growth and differentiation of these tissues during embryogenesis.
0 Communities
1 Members
0 Resources
20 MeSH Terms