Glucocorticoid-regulated microRNAs and mirtrons in acute lymphoblastic leukemia
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE11336 | GEO | 2009/01/16
SECONDARY ACCESSION(S): PRJNA106543
REPOSITORIES: GEO
Similar Datasets
Project description:Glucocorticoids (GC) have a major impact on the biology of normal and malignant cells of the lymphoid lineage. This includes induction of apoptosis which is exploited in the therapy of acute lymphoblastic leukemia (ALL) and related lymphoid malignancies. MicroRNAs (miRNAs), and the related mirtrons, are ~22 nucleotide RNA molecules implicated in the control of essential biological functions including proliferation, differentiation and apoptosis. They derive from polymerase-II transcripts but whether GCs regulate miRNA/mirtron-encoding transcription units is not known. We investigated miRNA/mirtron expression and GC regulation in 8 ALL in vitro models and 13 ALL children undergoing systemic GC monotherapy using a combination of expression profiling techniques, real time RT-PCR and northern blotting to detect mature miRNAs/mirtrons and/or their precursors. We identified a GC-regulated mirtron (miR-1233) and a number of GC-regulated miRNAs, including the myeloid-specific miR-223 and the apoptosis and cell cycle arrest-inducing mir15~16 cluster. However, the response was heterogeneous in individual patients and cell lines, the extent of regulation was moderate, and functional analyses of the most promising candidates (miR223 and the miR15~16 cluster) revealed little, if any effect, on cell cycle progression and survival. Thus, although GCs affect miRNA expression in ALL cells, these regulations may not be major contributors to the anti-leukemic GC effects. Keywords: exon analysis
2009-01-16 | GSE10910 | GEO
Project description:Glucocorticoids (GC) have a major impact on the biology of normal and malignant cells of the lymphoid lineage. This includes induction of apoptosis which is exploited in the therapy of acute lymphoblastic leukemia (ALL) and related lymphoid malignancies. MicroRNAs (miRNAs) and the related mirtrons are ~22 nucleotide RNA molecules implicated in the control of essential biological functions including proliferation, differentiation and apoptosis. They derive from polymerase-II transcripts but whether GCs regulate miRNA-encoding transcription units is not known. We investigated miRNA/mirtron expression and GC regulation in 8 ALL in vitro models and 13 ALL children undergoing systemic GC monotherapy using a combination of expression profiling techniques, real time RT-PCR and northern blotting to detect mature miRNAs and/or their precursors. We identified a number of GC-regulated miRNAs/mirtrons, including the myeloid-specific miR-223 and the apoptosis and cell cycle arrest-inducing mir15~16 cluster. Thus, the observed complex changes in miRNA/mirtron expression during GC treatment might contribute to the anti-leukemic GC effects in a cell context dependent manner. Experiment Overall Design: Glucocorticoid-sensitive T-ALL cell line CCRF-CEM-C7H2 was treated in 3 independent experiments either with 100nM dexametasone (a glucocorticoid) or 0.1% ethanol as an empty carrier control. Samples were taken at various timepoints (6 and 24 hours), RNA extracted and hybridized onto Affymetrix HGU133-plus2 microarrays. The microarray dataset was subsetted to probesets targetting potential primary microRNA transcripts (pri-miRNAs). Differentially expressed pri-miRNAs were identified for the comparisons of the 6h GC versus 6h EtOH (control) and for the 24h GC versus 24h EtOH (control) samples.
2009-01-25 | E-GEOD-11336 | biostudies-arrayexpress
Project description:A canonical pathway generates microRNAs (miRNAs) via stepwise cleavage of hairpin precursors by RNase III enzymes Drosha and Dicer, followed by loading of resultant ~22 nucleotide (nt) RNAs into an Argonaute (Ago) effector complex. In addition, non-canonical substrates can bypass either RNase III enzyme to yield functional small RNAs, including hundreds of intron-derived hairpins that comprise pre-miRNA mimics that bypass Drosha (i.e., mirtrons). Here, we show that mirtron breadth is much larger than currently appreciated, since hundreds of novel splicing-derived hairpins are detected in intermediate (~50-100 nt) but not small (20-30nt) RNA data. Since mirtrons were originally defined on the basis of small RNA duplexes, we term the larger set of loci as structured, splicing-derived RNAs (ssdRNAs). Although individual species generally accumulate modestly, these are broadly detected in Dicer and/or Ago complexes and can mediate repression in directed assays. Nevertheless, their extremely poor conservation suggests they do not generally benefit regulatory networks, and may instead contaminate the canonical miRNA pathway. In aggregate, ssdRNAs/mirtrons comprise the dominant hairpin substrates for 3' tailing by multiple terminal nucleotidyltransferases, notably TUT4/7 and TENT2. We provide evidence that hairpin tailing is inhibitory for ssdRNA/mirtron biogenesis and/or function, and that this pathway has restricted the evolution of canonical pre-miRNAs that resemble splicing products. Overall, the rampant proliferation of evolutionary young mammalian mirtrons, coupled with an attendant molecular defense, comprises a Red Queen's race of intragenomic conflict.
2022-12-25 | GSE206186 | GEO
Project description:Uridylation of diverse RNA species represents an emerging theme in post-transcriptional gene regulation. In the microRNA pathway, such modifications regulate small RNA biogenesis and stability in plants, worms and mammals. Here, we report the first uridylyltransferase that acts on small RNAs in Drosophila, which we refer to as Tailor. Tailor is the source for the majority of 3´ terminal uridine-modifications in small RNAs and predominantly targets precursor-miRNAs. Uridylation modulates the characteristic two-nucleotide 3´ overhangs of miRNA hairpins, which regulates pre-miRNA processing by Dicer-1. Furthermore, Tailor preferentially uridylates mirtron hairpins, thereby impeding the production of non-canonical microRNAs. Mirtron-selectivity is explained by unique primary sequence specificity of Tailor, selecting RNA substrates ending with a 3´ guanosine, a feature not previously observed for terminal uridylyltransferases. In contrast to mirtrons, conserved Drosophila pre-miRNAs are significantly depleted in 3´ guanosine, thereby escaping regulatory uridylation.Our data support the hypothesis that evolutionary adaptation to pre-miRNA uridylation shapes the nucleotide composition of pre-miRNA 3´ ends and may serve as a barrier for the de novo creation of miRNAs in Drosophila.
2015-10-19 | GSE66213 | GEO
Project description:Uridylation of diverse RNA species represents an emerging theme in post-transcriptional gene regulation. In the microRNA pathway, such modifications regulate small RNA biogenesis and stability in plants, worms and mammals. Here, we report the first uridylyltransferase that acts on small RNAs in Drosophila, which we refer to as Tailor. Tailor is the source for the majority of 3´ end-modifications in microRNAs and predominantly targets precursor-hairpins. Uridylation modulates the characteristic two-nucleotide 3´ overhangs of microRNA hairpins, which regulates processing by Dicer-1 and destabilizes RNA hairpins. Furthermore, Tailor preferentially uridylates mirtron-hairpins, thereby impeding the production of non-canonical microRNAs. Mirtron-selectivity is explained by unique primary sequence specificity of Tailor, selecting RNA substrates ending with a 3´ guanosine, a feature not previously observed for TUTases. In contrast to mirtrons, conserved Drosophila pre-miRNAs are significantly depleted in 3´ guanosine, thereby escaping regulatory uridylation. Our data support the hypothesis that evolutionary adaptation to pre-miRNA uridylation shapes the nucleotide composition of pre-miRNA 3´ ends. Hence, hairpin-uridylation may serve as a barrier for the de novo creation of miRNAs in Drosophila.
2015-10-19 | GSE67646 | GEO
Project description:Glucocorticoids (GCs) cause apoptosis in lymphoid lineage cells and are therefore widely used in the therapy of lymphoid malignancies. The molecular mechanisms of the anti-leukemic GC effects are, however, poorly understood. We have previously defined a list of GC-regulated candidate genes by Affymetrix-based whole genome comparative expression profiling in children with acute lymphoblastic leukemia (ALL) during systemic GC monotherapy and in experimental systems of GC-induced apoptosis. ZBTB16, a Zink finger and BOZ-domain containing transcriptional repressor, was one of the most promising candidates derived from this screen. To investigate its possible role in GC-induced apoptosis and cell cycle arrest, we performed conditional over-expression experiments in CCRF-CEM childhood ALL cells. Transgenic ZBTB16 alone had no detectable effect on survival, however, it reduced sensitivity to GC-induced apoptosis. This protective effect was not seen when apoptosis was induced by antibodies against Fas/CD95 or 3 different chemotherapeutics. To address the molecular mechanism underlying this protective effect, we performed whole genome expression profiling in cells with conditional ZBTB16 expression. Surprisingly, ZBTB16 induction did not significantly alter the expression profile, however, it interfered with the regulation of several GC response genes. One of them, BCL2L11/Bim, has previously been shown to be responsible for cell death induction in CCRF-CEM cells. Thus, ZBTB16´s protective effect can be attributed to interference with transcriptional regulation of apoptotic genes, at least in the investigated model system.
2010-05-07 | GSE15820 | GEO
Project description:<p>The biomarker development study consisted of two parts: discovery and validation. The first part was the discovery and verification phase of biomarkers using two different platforms: transcriptomic and miRNA. The salivary transcriptomes of 63 GC samples and 31 non-GC controls were profiled using Affymetrix HG U133+2.0 microarrays (Affymetrix, Santa Clara, CA). The identified exRNA candidates were verified by quantitative real-time PCR (RT-qPCR) using all 94 of the original samples. In the discovery phase for the miRNA biomarkers, 10 early-stage GC samples and 10 non-GC controls were selected. The salivary miRNAs of these samples (n=20) were profiled using the TaqMan MicroRNA Array (Applied Biosystems, Foster City, CA). MicroRNA candidates were verified using TaqMan miRNA Assay (Thermo Scientific, Grand Island, NY). The second part of the study was to validate these verified exRNA biomarker candidates with exRNA samples extracted from an independent cohort of 100 GC and 100 non-GC saliva samples. The cohort was not balanced for demographics on gender and smoking history but more accurately reflected the diagnostic setting where our proposed final model could be implemented.</p> <p>Reprinted from "Li F, Yoshizawa MJ, Kim K, Kanjanapangka J, Grogan T, Wang X, Elashoff D, Ishikawa S, Chia D, Liao W, Akin D, Yan X, Lee M, Choi R, Kim S, Kang S, Bae J, Sohn T, Lee J, Choi M, Min B, Lee J, Kim J, Kim Y, Kim S, Wong D. (2018) Development and Validation of Salivary Extracellular RNA Biomarkers for Noninvasive Detection of Gastric Cancer. Clin Chem. PMID: <a href="https://www.ncbi.nlm.nih.gov/pubmed/30097497">30097497</a> DOI: 10.1373/clinchem.2018.290569", with permission from American Association for Clinical Chemistry (United States). </p>
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Project description:MicroRNA (miRNA) and other types of small regulatory RNAs play a crucial role in the regulation of gene expression in eukaryotes. Several distinct classes of small regulatory RNAs have been discovered in recent years. To extend the repertoire of small regulatory RNAs characterized in chickens we used a deep sequencing approach developed by Solexa (now Illumina Inc.). We sequenced three small RNA libraries prepared from different developmental stages of the chicken embryo (days 5, 7, and 9) to produce over 9.5 million short sequence reads. We developed a bioinformatics pipeline to distinguish authentic mature miRNA sequences from other classes of small RNAs and short RNA fragments represented in the sequencing data. Using this approach we detected almost all of the previously known chicken miRNAs and their respective miRNA* sequences. In addition we discovered 449 putative new chicken miRNAs. Of these, 430 miRNAs appear to be specific to the avian lineage. Another 6 new miRNAs had evidence of evolutionary conservation in at least one vertebrate species outside of the bird lineage. The remaining 13 putative miRNAs appear to represent chicken orthologs of known vertebrate miRNAs. We discovered 39 additional putative miRNA candidates originating from miRNA generating intronic sequences known as mirtrons. Keywords: miRNA discovery, mirtrons, chicken embryo 3 samples
2008-05-11 | E-GEOD-10686 | biostudies-arrayexpress
Project description:MicroRNA (miRNA) and other types of small regulatory RNAs play a crucial role in the regulation of gene expression in eukaryotes. Several distinct classes of small regulatory RNAs have been discovered in recent years. To extend the repertoire of small regulatory RNAs characterized in chickens we used a deep sequencing approach developed by Solexa (now Illumina Inc.). We sequenced three small RNA libraries prepared from different developmental stages of the chicken embryo (days 5, 7, and 9) to produce over 9.5 million short sequence reads. We developed a bioinformatics pipeline to distinguish authentic mature miRNA sequences from other classes of small RNAs and short RNA fragments represented in the sequencing data. Using this approach we detected almost all of the previously known chicken miRNAs and their respective miRNA* sequences. In addition we discovered 449 putative new chicken miRNAs. Of these, 430 miRNAs appear to be specific to the avian lineage. Another 6 new miRNAs had evidence of evolutionary conservation in at least one vertebrate species outside of the bird lineage. The remaining 13 putative miRNAs appear to represent chicken orthologs of known vertebrate miRNAs. We discovered 39 additional putative miRNA candidates originating from miRNA generating intronic sequences known as mirtrons. Keywords: miRNA discovery, mirtrons, chicken embryo
2008-05-12 | GSE10686 | GEO
Project description:In this study, the viral miRNAs from white spot syndrome virus (WSSV) were characterized in shrimp in vivo. On the basis of our previous study and small RNA sequencing in this study, a total of 89 putative WSSV miRNAs were identified. As revealed by miRNA microarray analysis, the expressions of viral miRNAs were tissue-specific in vivo. In this study, the viral miRNAs from white spot syndrome virus (WSSV) were characterized in shrimp in vivo. On the basis of our previous study and small RNA sequencing in this study, a total of 89 putative WSSV miRNAs were identified. As revealed by miRNA microarray analysis and Northern blots, the expressions of viral miRNAs were tissue-specific in vivo. Therefore, our study presented the first report on the in vivo molecular events of viral miRNA in the antiviral apoptosis.
2014-01-09 | E-GEOD-53900 | biostudies-arrayexpress