Background: FGF signaling controls numerous processes during cell lineage specification, organogenesis and terminal differentiation. In lens, FGF signaling was implicated as the key pathway that controls lens fiber cell differentiation, but little is known about its full range and spectrum of regulated genes. Results: Herein, we employed rat lens epithelial explant system and performed RNA and microRNA expression profiling in cells induced to differentiate by FGF2. The primary data were collected at explants grown overnight in the presence of 5 ng/ml of FGF2, followed by a treatment with 100 ng/ml of FGF2 and collection of samples at 2, 4, 12 and 24 hours. Global analysis identified extensive FGF2-regulated cellular responses that were both independent and dependent on microRNAs (miRNAs). We identified a total number of 131 FGF2-regulated miRNAs. Forty-four of these microRNAs had at least two predicted and inversely regulated target RNA molecules. The genes regulated by the highest number of miRs include Nfib, Nfat5, c-Maf, Ets1 and N-Myc, all encoding DNA-binding transcription factors. Analysis of RNA data revealed that activated FGF signaling influenced other major signaling pathways known to regulate lens differentiation including BMP/TGF-, Notch, and Wnt signaling. In the early response phase (2-4 hours), miRNAs targeted expression of batteries of genes that control transcription, cell death, cell proliferation, cell junction, and protein serine/threonine kinase activity. In late stages (12-24 hours), the main miRNA targets included regulators of cell cycle arrest and cellular differentiation. Specific miRNA:mRNA interaction networks were identified for c-Maf, N-Myc, and Nfib (DNA-binding transcription factors); Cnot6, Dicer1, Fbx33 and Wdr47 (RNA processing); Ash1l, Med1/PBP and Kdm5b (chromatin remodeling); and c-Maf, Ets1 and Stc1 (FGF signaling). MicroRNAs including miR-9, -143, -155, -455 and -543 downregulated expression of c-Maf in the 3-UTR luciferase reporter asssays. The functional requirement for miRNAs in lens was further demonstrated via disrupted lens fiber cell differentiation in lenses with inactivated Dicer1. Conclusions: These studies demonstrate for the first time global impact of activated FGF signaling in lens cell culture system and identified novel gene regulatory networks (GRNs) connected by multiple miRNAs.
Identification and characterization of FGF2-dependent mRNA: microRNA networks during lens fiber cell differentiation.
Specimen part
View SamplesBackground: E-cadherin is an adherens junction protein that forms homophilic intercellular contacts in epithelial cells while also interacting with the intracellular cytoskeletal networks. It has roles including establishment and maintenance of cell polarity, differentiation, migration and signalling in cell proliferation pathways. Its downregulation is commonly observed in epithelial tumours and is a hallmark of the epithelial to mesenchymal transition (EMT). Methods: To improve our understanding of how E-cadherin loss contributes to tumorigenicity, we investigated the impact of its elimination from the non-tumorigenic breast cell line MCF10A. We performed cell-based assays and whole genome RNAseq to characterize an isogenic MCF10A cell line that is devoid of CDH1 expression due to an engineered homozygous 4bp deletion in CDH1 exon 11. Results: The E-cadherin-deficient line, MCF10A CDH1-/- showed subtle morphological changes, weaker cell-substrate adhesion, delayed migration, but retained cell-cell contact, contact growth inhibition and anchorage-dependent growth. Within the cytoskeleton, the apical microtubule network in the CDH1-deficient cells lacked the radial pattern of organization present in the MCF10A cells and F-actin formed thicker, more numerous stress fibres in the basal part of the cell. Whole genome RNAseq identified compensatory changes in the genes involved in cell-cell adhesion while genes involved in cell-substrate adhesion, notably ITGA1, COL8A1, COL4A2 and COL12A1, were significantly downregulated. Key EMT markers including CDH2, FN1, VIM and VTN were not upregulated although increased expression of proteolytic matrix metalloprotease and kallikrein genes was observed. Conclusions: Overall, our results demonstrated that E-cadherin loss alone was insufficient to induce an EMT or enhance transforming potential in the non-tumorigenic MCF10A cells but was associated with broad transcriptional changes associated with tissue remodelling. Overall design: Examination of the impact of E-cadherin (CDH1) loss in an isogenic pair of breast cell lines.
E-cadherin loss alters cytoskeletal organization and adhesion in non-malignant breast cells but is insufficient to induce an epithelial-mesenchymal transition.
No sample metadata fields
View SamplesComparison of the meis2b+ and the meis2b- halves of the atrium of the adult zebrafish atrium reveals the existence of two different transcriptional domains. These two domains analogous to that of the two atria in terrestrial vertebrates Overall design: To determine the expression profiles of the Tg(meis2b-reporter)-positive vs -negative atrial compartments, a total of 6 hearts of 3 mpf Tg(meis2b-reporter) zebrafish were micro-dissected. A total of 4 pools were made: the first two pools, each contained 3 Tg(meis2b-reporter)-positive atrial compartments, and the other two contained the Tg(meis2b-reporter)-negative halves.
Distinct myocardial lineages break atrial symmetry during cardiogenesis in zebrafish.
Age, Specimen part, Cell line, Subject
View SamplesTriple-negative (TN) breast cancers need to be refined in order to identify therapeutic subgroups of patients.
Gene-expression molecular subtyping of triple-negative breast cancer tumours: importance of immune response.
Disease
View SamplesrGal1 (recombinant Galectin-1) vs non treated (Ctrl) pancreatic cancer cell line RWP-1
Targeting galectin-1 inhibits pancreatic cancer progression by modulating tumor-stroma crosstalk.
Specimen part, Cell line
View SamplescAMP receptor protein (CRP, also known as the catabolite activator protein [CAP]) is arguably the best-studied of the global transcription factors of E coli. CRP alone is responsible for regulating at least 283 operons. Upon binding cAMP, the CRP dimer binds DNA and directly interacts with RNA polymerase (RNAP). At Class II promoters, CRP binds near position -41,5 relative to the transcription start site and contacts the amino-terminal domain of the RNAP subunit (RNAP-NTD). This interaction requires AR2, a patch of primarily positively charged residues (H19, H21, E96, and K101) that interact with negatively charged residues on RNAP-NTD. Acetylome analyses consistently detect lysine 100 (K100) of CRP as acetylated. Since K100 is adjacent to the positively charged AR2, we hypothesized that the K100 positive charge may also play a role in CRP function. We further hypothesized that acetylation of K100 would neutralize this positive charge, leading to a potential regulatory mechanism
Influence of Glucose Availability and CRP Acetylation on the Genome-Wide Transcriptional Response of <i>Escherichia coli</i>: Assessment by an Optimized Factorial Microarray Analysis.
No sample metadata fields
View SamplesPMID: 15539473. We compared the gene expression in roots between WT and fit mutant under +Fe and -Fe conditions using ATH1 microarray analysis to explore which genes are affected by the loss of FIT function.
The essential basic helix-loop-helix protein FIT1 is required for the iron deficiency response.
Specimen part, Treatment
View SamplesThe aim of this study was to determine the effect of transgenic Aire expression on the transcriptional profile of a tissue that normally does not express Aire: pancreatic islets. The transcriptional profile of transgenic RIP-Aire27 islets was compared to non-transgenic littermate islets as well as to archival NOD thymic medullary epithelial cells (MEC) data. All data were from non-obese diabetic (NOD) mice
Transcriptional impact of Aire varies with cell type.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Promiscuous targeting of bromodomains by bromosporine identifies BET proteins as master regulators of primary transcription response in leukemia.
Cell line, Treatment
View SamplesBromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET inhibitors and their significant activity in diverse tumor models has rapidly translated into clinical studies and has motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of bromodomain protein complexes complicates predictions of consequences of their pharmacological targeting. To address this issue we developed a promiscuous bromodomain inhibitor (bromosporine, BSP) that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle we studied the effect of BSP in leukemic cell-lines known to be sensitive to BET inhibition and found as expected strong anti-proliferative activity. Comparison of the modulation of transcriptional profiles by BSP at short inhibitor exposure resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, non-selective targeting of BRDs identified BETs, but not other BRDs, as master regulators of a context dependent primary transcription response.
Promiscuous targeting of bromodomains by bromosporine identifies BET proteins as master regulators of primary transcription response in leukemia.
Cell line, Treatment
View Samples