The retinal pigment epithelium (RPE) provides vital support to photoreceptor cells and its dysfunction is associated with the onset and progression of age-related macular degeneration (AMD). Surgical provision of RPE cells may ameliorate AMD and thus it would be valuable to develop sources of patient-matched RPE cells for this application of regenerative medicine. We describe here the generation of functional RPE-like cells from fibroblasts that represent an important step toward that goal. We identified candidate master transcriptional regulators of RPEs using a novel computational method and then used these regulators to guide exploration of the transcriptional regulatory circuitry of RPE cells and to reprogram human fibroblasts into RPE-like cells. The RPE-like cells share key features with RPEs derived from healthy individuals, including morphology, gene expression and function, and thus represent a step toward the goal of generating patient-matched RPE cells for treatment of macular degeneration.
A Systematic Approach to Identify Candidate Transcription Factors that Control Cell Identity.
Specimen part
View SamplesWe used microarrays to detail the global transcriptional response mediated by ERalpha or ERbeta to the phytoestrogen genistein in the MCF-7 human breast cancer cell model.
Estrogen Receptors alpha and beta as determinants of gene expression: influence of ligand, dose, and chromatin binding.
No sample metadata fields
View SamplesHSFA1s are a gene family of HSFA1 with four members, HSFA1a, HSFA1b, HSFA1d, and HSFA1e. HSFA1s are the master regulators of heat shock response. As a part of the heat shock response, HSFA2 can prolong the heat shock response and amplify the heat shock response in response to repeat heat shock. To identify the heat-shock-responsive genes differentially regulated by HSFA1s and HSFA2, we compared the transcriptomic differences of plants containing only constitutively expressed HSFA1s or HSFA2 after heat stress.
Common and distinct functions of Arabidopsis class A1 and A2 heat shock factors in diverse abiotic stress responses and development.
Age, Specimen part
View SamplesThe study demontrates differences in the transcriptome ( both of protein coding transcripts and long non-coding RNAs) in the unilateral ureteric obstruction model of renal fibrosis. Overall design: Renal tissue was studied from animals undergoing sham operation (as controls) or right ureteric ligation. Animals were sacrificed 2 and 8 days following ligation and the right kidney tissue was examined.
Whole-transcriptome analysis of UUO mouse model of renal fibrosis reveals new molecular players in kidney diseases.
Sex, Age, Specimen part, Cell line, Subject
View SamplesInflammatory breast cancer (IBC) is an aggressive form of BC poorly defined at the molecular level. We compared the molecular portraits of 63 IBC and 134 non-IBC (nIBC) clinical samples. Genomic imbalances of 49 IBCs and 124 nIBCs were determined using high-resolution array-comparative genomic hybridization, and mRNA expression profiles of 197 samples using whole-genome microarrays. Genomic profiles of IBCs were as heterogeneous as those of nIBCs, and globally relatively close. However, IBCs showed more frequent complex patterns and a higher percentage of genes with CNAs per sample. The number of altered regions was similar in both types, although some regions were altered more frequently and/or with higher amplitude in IBCs. Many genes were similarly altered in both types; however, more genes displayed recurrent amplifications in IBCs.
High-resolution comparative genomic hybridization of inflammatory breast cancer and identification of candidate genes.
Age
View SamplesThe nuclear receptor, estrogen receptor alpha (ER), controls the expression of hundreds of genes responsible for target cell phenotypic properties, but the relative importance of direct vs. tethering mechanisms of DNA binding has not been established. In this first report, we examine the genome-wide chromatin localization of an altered-specificity mutant ER with a DNA-binding domain deficient in binding to estrogen response element (ERE)-containing DNA (DBDmut ER) vs. wild type ER. Using high-throughput sequencing of ER chromatin immunoprecipitations (ChIP-Seq) and mRNA transcriptional profiling, we show that direct ERE binding is required for most (75%) estrogen-dependent gene regulation and 90% of hormone-dependent recruitment of ER to genomic binding sites. De novo motif analysis of the chromatin binding regions in MDA-MB-231 human breast cancer cells defined unique transcription factor profiles responsible for genes regulated through tethering vs. direct DNA (ERE) binding, with Runx motifs enriched in ER-tethered sites. We confirmed a role for Runx1 in mediating ERa genomic recruitment and regulation of tethering genes. Our findings delineate the contributions of ERE binding vs. binding through response elements for other transcription factors in chromatin localization and ER-dependent gene regulation, paradigms likely to underlie the gene regulatory actions of other nuclear receptors as well.
Genome-wide analysis of estrogen receptor alpha DNA binding and tethering mechanisms identifies Runx1 as a novel tethering factor in receptor-mediated transcriptional activation.
Specimen part, Time
View SamplesEstradiol Timecourse of MDA-MB-231ER+ cells containing a WT-ER and DBDmut-ER
Genome-wide analysis of estrogen receptor alpha DNA binding and tethering mechanisms identifies Runx1 as a novel tethering factor in receptor-mediated transcriptional activation.
Time
View SamplesIn order to study the importance of HSFA1 in thermotolerance in Arabidopsis, we generated the HSFA1a, b, d and e quadruple mutant (QK). QK is very sensitive to heat. Therefore, we used microarray to study how many genes regulated by HSFA1 after heat shock.
The role of class A1 heat shock factors (HSFA1s) in response to heat and other stresses in Arabidopsis.
Age, Specimen part, Treatment
View SamplesAnalysis of the response to arginine of the Escherichia coli K-12 transcriptome by microarray hybridization and real-time quantitative PCR provides a first coherent quantitative picture of the ArgR-mediated repression of arginine biosynthesis and uptake genes. Transcriptional repression was shown to be the major control mechanism of the biosynthetic genes, leaving only limited room for additional transcriptional or post-transcriptional regulations. The art genes coding for the specific arginine uptake system are subject to ArgR-mediated repression,
The arginine regulon of Escherichia coli: whole-system transcriptome analysis discovers new genes and provides an integrated view of arginine regulation.
No sample metadata fields
View SamplesScreening small molecules and drugs for activity to modulate alternative splicing, we found that amiloride, distinct from four other intracellular pH-affecting analogues, could normalize the splicing of BCL-X, HIPK3 and RON/MISTR1 transcripts in human hepatocellular carcinoma Huh-7 cells. To elucidate the underlying mechanisms, our proteomic analyses of amiloride-treated cells detected hypo-phosphorylation of splicing factor SF2/ASF and also decreased levels of SRp20 and two un-identified SR proteins. We further observed decreased phosphorylation of AKT, ERK1/2 and PP1, while increased phosphorylation of p38 and JNK, suggesting that amiloride treatment down-regulated kinases and up-regulated phosphatases in the signal pathways known to affect the splicing factor protein phosphorylation. The amiloride effects of splicing factor protein hypo-phosphorylation andnormalizedoncogenic RNA splicing were both abrogated by pre-treatment with a PP1 inhibitor. We then performed global exon array analysis of Huh-7 cells treated with amiloride for 24 hours. Using gene array chips (Affymetrix GeneChip Human Exon 1.0 ST Array of >518000 exons of 42974 genes) for exon array analysis (set parameters of correlation coefficient 0.7, splicing index -1.585 , and log2 ratio -1.585), we found that amiloride influenced the splicing patterns of 551 genes involving at least 584 exons, which included 495 known protein-coding genes involving 526 exons, many of which play key roles in functional networks of ion transport, extracellular matrix, cytoskeletons and genome maintenance. Cellular functional analyses revealed subsequent invasion and migration defects, cell cycle disruption, cytokinesis impairment, and lethal DNA degradation in amiloride-treated Huh-7 cells. This study thus provides mechanistic underpinnings for exploiting small molecule modulation of abnormal RNA splicing for cancer therapeutics.
Small molecule amiloride modulates oncogenic RNA alternative splicing to devitalize human cancer cells.
Cell line
View Samples