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GSE14537
Homo sapiens
18 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Relative contribution of sequence and structural features to the mRNA-binding of Argonaute/miRNA complexes and the degradation of miRNA targets
Publication Title
Relative contribution of sequence and structure features to the mRNA binding of Argonaute/EIF2C-miRNA complexes and the degradation of miRNA targets.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 13 Downloadable Samples
Illumina Genome Analyzer IIx
Description
Crosslinking and immunoprecipitation (CLIP) is increasingly used to map transcriptome-wide binding sites of RNA-binding proteins (RBPs). We developed a method for CLIP data analysis and applied it to compare 254 nm CLIP with PAR-CLIP, which involves crosslinking of photoreactive nucleotides with 365 nm UV light. We found small differences in the accuracy of these methods in identifying binding sites of HuR, a protein that binds low-complexity sequences and Argonaute 2, which has a complex binding specificity. We show that crosslink-induced mutations lead to single-nucleotide resolution for both PAR-CLIP and CLIP. Our results confirm the expectation from original CLIP publications that RNA-binding proteins do not protect sufficiently their sites under the denaturing conditions used during the CLIP procedure, and we show that extensive digestion with sequence-specific ribonucleases strongly biases the set of recovered binding sites. We finally show that this bias can be substantially reduced by milder nuclease digestion conditions. Overall design: We performed duplicate experiments for each variant of the CLIP protocol (CLIP, PAR-CLIP), each protein (HuR, Ago2), and enzymatic digestion (complete T1 digestion, mild MNase digestion). In addition, we performed a single PAR-CLIP experiment with mild T1 digestion.
Publication Title
A quantitative analysis of CLIP methods for identifying binding sites of RNA-binding proteins.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 18 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Herpesviruses are known to encode micro (mi)RNAs and to use them to regulate the expression of both viral and cellular genes. The genome of Kaposis sarcoma herpesvirus (KSHV) encodes a cluster of twelve miRNAs, which are abundantly expressed during both latency and lytic infection. Relatively few cellular targets of KSHV miRNAs are known. Here, we used a microarray expression profiling approach to analyze the transcriptome of both B lymphocytes and endothelial cells stably expressing KSHV miRNAs and monitor the changes induced by the presence of these miRNAs. We generated a list of potential cellular targets by looking for miRNA seed-match-containing transcripts that were significantly down regulated upon KSHV miRNAs expression. Interestingly, the overlap of putative targets identified in B lymphocytes and endothelial cells was minimal, suggesting a tissue-specific target-regulation by viral miRNAs. Among the putative targets, we identified caspase 3, a critical factor for the control of apoptosis, which we validated using luciferase reporter assays and western blotting. In functional assays we obtained further evidence that KSHV miRNAs indeed protect cells from apoptosis.
Publication Title
Kaposi's sarcoma herpesvirus microRNAs target caspase 3 and regulate apoptosis.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Transcriptional and posttranscriptional regulatory networks play a crucial role in the maintenance and adaptation of pancreatic beta-cell function. In this study we show that the levels of the prototypic neuroendocrine miRNA-7 are regulated in islets of obese, diabetic and aged mouse models. Using gain- and loss-of-function models we demonstrate that miR-7 regulates crucial members of the endocrine pancreatic transcriptional network controlling differentiation and insulin synthesis. Importantly, it also directly regulates key proteins in the insulin granule secretory machinery. These results reveal an interconnecting miR-7 genomic circuit that influences beta-cell differentiation, insulin synthesis and release and define a role for miR-7 as an endocrine checkpoint to stabilize beta-cell function during metabolic stress. These findings have implications for miR-7 inhibitors as potential therapies for type 2 diabetes and neurodegenerative diseases.
Publication Title
MicroRNA-7a regulates pancreatic β cell function.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 14 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Transcriptome-wide identification of RNA-binding protein and microRNA target sites by PAR-CLIP.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 6 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To assess whether the transcripts identified by PAR-CLIP are regulated by the RNA-binding protein (RBP) Quaking (QKI), we analyzed the mRNA levels of mock-transfected and QKI-specific siRNA-transfected cells with microarrays. Transcripts crosslinked to QKI were significantly upregulated upon siRNA transfection, indicating that QKI negatively regulates bound mRNAs (Figure 3H of PMID 20371350), consistent with previous reports of QKI being a repressor.
Publication Title
Transcriptome-wide identification of RNA-binding protein and microRNA target sites by PAR-CLIP.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To test the influence of IGF2BPs on the stability of their interacting mRNAs, as reported previously for some targets (Yisraeli, 2005), we simultaneously depleted all three IGF2BP family members using siRNAs and compared the cellular RNA from knockdown and mock-transfected cells on microarrays. The levels of transcripts identified by PAR-CLIP decreased in IGF2BP-depleted cells, indicating that IGF2BP proteins stabilize their target mRNAs. Moreover, transcripts that yielded clusters with the highest T to C mutation frequency were most destabilized (Figure 4G of PMID 20371350), indicating that the ranking criterion that we derived based on the analysis of PUM2 and QKI data generalizes to other RNA-binding proteins (RBPs).
Publication Title
Transcriptome-wide identification of RNA-binding protein and microRNA target sites by PAR-CLIP.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To obtain evidence that Argonaute (AGO) crosslink-centered regions (CCRs) indeed contain functional miRNA-binding sites, we blocked 25 of the most abundant miRNAs in HEK 293 cells (Figure 5C of PMID 20371350) by transfection of a cocktail of 2'-O-methyl-modified antisense oligoribonucleotides and monitored the changes in mRNA stability by microarrays (Figure 7A of PMID 20371350). Consistent with previous studies of individual miRNAs (Grimson et al., 2007), the magnitude of the destabilization effects of transcripts containing at least one CCR depended on the length of the seed-complementary region and dropped from 9-mer to 8-mer to 7-mer to 6-mer matches (Figure 7B of PMID 20371350). We did not find evidence for significant destabilization of transcripts that only contained imperfectly paired seed regions.
Publication Title
Transcriptome-wide identification of RNA-binding protein and microRNA target sites by PAR-CLIP.
Sample Metadata Fields
Cell line
View Samples- Drosophila melanogaster
- 13 Downloadable Samples
- Affymetrix Drosophila Genome Array (drosgenome1)
Description
Ewg differentially regulated genes in 16-18 h Drosophila embryos. The experiment contains expression measurements from wild type, ewg l1 protein null allele and ewg l1 elavEWG (elavEWG rescue construct expressing a ewg cDNA from the elav promoter) mutants.
Publication Title
Erect wing regulates synaptic growth in Drosophila by integration of multiple signaling pathways.
Sample Metadata Fields
Age
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Illumina HiSeq 2500
Description
Methylation of mRNA at the N6 position of adenosin is known for a long time, but its function remains poorly understood. Here generated a null mutant in the catalytic subunit of the m6A mRNA methylosome, dIME4, in Drosophila to determine the impact of loss of m6A on gene expression using Illumina sequencing. Overall design: Since dIME4 is preferentially expressed in the nervous system and dIME4 null mutants are viable, we compared gene expression and alternative splicing in wild type (2 samples) and dIME4 mutants (3 samples) with genetic background matched w control females in neuron enriched head/thorax.
Publication Title
m<sup>6</sup>A potentiates Sxl alternative pre-mRNA splicing for robust Drosophila sex determination.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples