Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA105107 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:This SuperSeries is composed of the following subset Series:; GSE9757: Response to estradiol-ERalpha; GSE9758: Response to estradiol-ERalpha ERE Binding defective mutant; GSE9759: Response to estradiol-Erbeta and estradiol-ERbeta ERE binding defective mutant Experiment Overall Design: Refer to individual Series
2008-06-16 | E-GEOD-9761 | biostudies-arrayexpress
Project description:Response to estradiol-ERbeta and estradiol-ERbeta ERE binding defective mutant
| PRJNA105109 | ENA
Project description:ChIP followed by deep sequencing was performed with antibodies to ERalpha in U2OS-ERalpha cells treated with 17beta-estradiol. Examination of Eralpha binding sites in U2OS-Eralpha cells. Sequenced input was used as a control
2011-05-03 | E-GEOD-28918 | biostudies-arrayexpress
Project description:We used ChIP-Seq to map ERalpha binding sites and to profile changes in RNA polymerase II (RNAPII) occupancy in MCF-7 cells in response to estradiol (E2), tamoxifen or fulvestrant. We identified 10,205 high confidence ERalpha binding sites in response to E2 of which 68% contained an estrogen response element (ERE) and only 7% contained a FOXA1 motif. Remarkably, 596 genes already change significantly in RNAPII occupancy (59% up and 41% down) following one hour of E2 exposure. Although pausing of RNA polymerase II occurs frequently in MCF-7 cells (17%) it is only observed on a minority of E2-regulated genes (4%). Tamoxifen and fulvestrant partially reduce ERalpha DNA binding and prevent RNAPII loading on the promoter and coding body on E2-upregulated genes. Both antagonists act differently on E2-downregulated genes. Tamoxifen acts as an agonist, also downregulating these genes while fulvestrant antagonizes E2 induced repression and often increases RNAPII occupancy. Furthermore our data identified genes preferentially regulated by tamoxifen but not by E2 or fulvestrant. Thus, antagonist loaded ERalpha acts mechanistically different on E2-activated and E2-repressed genes. Examination of ERalpha binding sites upon the binding of different ligands and association with transcription via RNAPII occupancy.
2009-03-09 | E-GEOD-14664 | biostudies-arrayexpress
Project description:We used ChIP-Seq to map ERalpha binding sites and to profile changes in RNA polymerase II (RNAPII) occupancy in MCF-7 cells in response to estradiol (E2), tamoxifen or fulvestrant. We identified 10,205 high confidence ERalpha binding sites in response to E2 of which 68% contained an estrogen response element (ERE) and only 7% contained a FOXA1 motif. Remarkably, 596 genes already change significantly in RNAPII occupancy (59% up and 41% down) following one hour of E2 exposure. Although pausing of RNA polymerase II occurs frequently in MCF-7 cells (17%) it is only observed on a minority of E2-regulated genes (4%). Tamoxifen and fulvestrant partially reduce ERalpha DNA binding and prevent RNAPII loading on the promoter and coding body on E2-upregulated genes. Both antagonists act differently on E2-downregulated genes. Tamoxifen acts as an agonist, also downregulating these genes while fulvestrant antagonizes E2 induced repression and often increases RNAPII occupancy. Furthermore our data identified genes preferentially regulated by tamoxifen but not by E2 or fulvestrant. Thus, antagonist loaded ERalpha acts mechanistically different on E2-activated and E2-repressed genes.
2009-03-09 | GSE14664 | GEO
Project description:Genome-wide analysis of ERalpha binding sites in U2OS-ERalpha cells
| PRJNA140575 | ENA
Project description:ChIP followed by deep sequencing was performed with antibodies to ERalpha in U2OS-ERalpha cells treated with 17beta-estradiol.
2011-05-03 | GSE28918 | GEO
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
| S-EPMC2531291 | biostudies-literature