Transcriptome-wide miR-155 binding map reveals widespread non-canonical microRNA targeting [mRNA expression data]
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE41241 | GEO | 2012/11/09
SECONDARY ACCESSION(S): PRJNA176304
REPOSITORIES: GEO
Similar Datasets
Project description:microRNAs (miRNAs) are essential components of gene regulation, but identification of miRNA targets remains a major challenge. Most target prediction and discovery relies on perfect complementarity of the miRNA seed to the 3’ untranslated region (UTR). However, it is unclear to what extent miRNAs target sites without seed matches. Here, we performed a transcriptome-wide identification of the endogenous targets of a single miRNA—miR-155—in a genetically controlled manner. We found that approximately forty percent of miR-155-dependent Argonaute binding occurs at sites without perfect seed matches. The majority of these non-canonical sites feature extensive complementarity to the miRNA seed with one mismatch. These non-canonical sites confer regulation of gene expression albeit less potently than canonical sites. Thus, non-canonical miRNA binding sites are widespread, often contain seed-like motifs, and can regulate gene expression, generating a continuum of targeting and regulation. Argonaute (AGO) HITS-CLIP Libraries generated from wild type and miR-155 knockout activated T cells.
2012-11-09 | GSE41285 | GEO
Project description:microRNAs (miRNAs) are essential components of gene regulation, but identification of miRNA targets remains a major challenge. Most target prediction and discovery relies on perfect complementarity of the miRNA seed to the 3’ untranslated region (UTR). However, it is unclear to what extent miRNAs target sites without seed matches. Here, we performed a transcriptome-wide identification of the endogenous targets of a single miRNA—miR-155—in a genetically controlled manner. We found that approximately forty percent of miR-155-dependent Argonaute binding occurs at sites without perfect seed matches. The majority of these non-canonical sites feature extensive complementarity to the miRNA seed with one mismatch. These non-canonical sites confer regulation of gene expression albeit less potently than canonical sites. Thus, non-canonical miRNA binding sites are widespread, often contain seed-like motifs, and can regulate gene expression, generating a continuum of targeting and regulation. We used microarrays to measure changes in gene expression between activated wild type (WT) and miR-155 deficient (155KO) primary CD4 T cells. CD4 T cells were harvested from WT and miR-155 KO mice (Thai et al., 2007) and activated for 3 days in vitro. Each array is from a separate biological replicate, which are cells originating from a separate mouse.
2012-11-09 | E-GEOD-41241 | biostudies-arrayexpress
Project description:microRNAs (miRNAs) are essential components of gene regulation, but identification of miRNA targets remains a major challenge. Most target prediction and discovery relies on perfect complementarity of the miRNA seed to the 3’ untranslated region (UTR). However, it is unclear to what extent miRNAs target sites without seed matches. Here, we performed a transcriptome-wide identification of the endogenous targets of a single miRNA—miR-155—in a genetically controlled manner. We found that approximately forty percent of miR-155-dependent Argonaute binding occurs at sites without perfect seed matches. The majority of these non-canonical sites feature extensive complementarity to the miRNA seed with one mismatch. These non-canonical sites confer regulation of gene expression albeit less potently than canonical sites. Thus, non-canonical miRNA binding sites are widespread, often contain seed-like motifs, and can regulate gene expression, generating a continuum of targeting and regulation. Argonaute (AGO) HITS-CLIP Libraries generated from wild type and miR-155 knockout activated T cells. AGO HITS-CLIP libraries were generated from activated wild type and miR-155 knockout T cells with two different 3' linkers. Libraries were generated and sequenced with an 11nt index read that contained both a 5nt multiplexing index and a 6nt degenerate barcode. Files have been demultiplexed and the 6nt degenerate barcode has been appended as the first 6 nucleotides of the read.
2012-11-09 | E-GEOD-41285 | biostudies-arrayexpress
Project description:Unlike short interfering RNAs (siRNAs), which are commonly designed to repress a single messenger RNA (mRNA) target through perfect base pairing, microRNAs (miRNAs) are endogenous small RNAs that have evolved to concurrently repress multiple mRNA targets through imperfect complementarity. MicroRNA target recognition is primarily determined by pairing of the miRNA seed sequence (nucleotides 2–8) to complementary match sites in each mRNA target. Whereas siRNA technology is well established for single target knockdown, the design of artificial miRNAs for multi-target repression is largely unexplored. We designed and functionally analysed over 200 artificial miRNAs for simultaneous repression of pyruvate carboxylase and glutaminase by selecting all seed matches shared by their 3′ untranslated regions. Although we identified multiple miRNAs that repressed endogenous protein expression of both genes, seed-based artificial miRNA design was highly inefficient, as the majority of miRNAs with even perfect seed matches did not repress either target. Moreover, commonly used target prediction programs did not substantially discriminate effective artificial miRNAs from ineffective ones, indicating that current algorithms do not fully capture the features important for artificial miRNA targeting and are not yet sufficient for designing artificial miRNAs. Our analysis suggests that additional factors are strong determinants of the efficacy of miRNA-mediated target repression and remain to be discovered. 293T cells were transiently transfected with artificial miRNAs or non-targeting control (Allstars siRNA, Qiagen). Three replicate transfections were performed for each miRNA or control. Total RNA was extracted 48 hours after transfection.
2014-02-28 | E-GEOD-50249 | biostudies-arrayexpress
Project description:Unlike short interfering RNAs (siRNAs), which are commonly designed to repress a single messenger RNA (mRNA) target through perfect base pairing, microRNAs (miRNAs) are endogenous small RNAs that have evolved to concurrently repress multiple mRNA targets through imperfect complementarity. MicroRNA target recognition is primarily determined by pairing of the miRNA seed sequence (nucleotides 2–8) to complementary match sites in each mRNA target. Whereas siRNA technology is well established for single target knockdown, the design of artificial miRNAs for multi-target repression is largely unexplored. We designed and functionally analysed over 200 artificial miRNAs for simultaneous repression of pyruvate carboxylase and glutaminase by selecting all seed matches shared by their 3′ untranslated regions. Although we identified multiple miRNAs that repressed endogenous protein expression of both genes, seed-based artificial miRNA design was highly inefficient, as the majority of miRNAs with even perfect seed matches did not repress either target. Moreover, commonly used target prediction programs did not substantially discriminate effective artificial miRNAs from ineffective ones, indicating that current algorithms do not fully capture the features important for artificial miRNA targeting and are not yet sufficient for designing artificial miRNAs. Our analysis suggests that additional factors are strong determinants of the efficacy of miRNA-mediated target repression and remain to be discovered.
2014-02-28 | GSE50249 | GEO
Project description:To exert regulatory function, miRNAs guide Argonaute (AGO) proteins to partially complementary sites on target RNAs. Crosslinking and immunoprecipitation (“re state-of-the-art to map AGO binding sites, but assigning the targeting miRNA to these sites relies on bioinformatics predictions and is therefore indirect. To directly and unambiguously identify miRNA:target site interactions, we modified our CLIP methodology in C. elegans to experimentally ligate miRNAs to their target sites. Unexpectedly, ligation reactions also occurred in absence of the exogenous ligase. Our in vivo dataset and re-analysis of published mammalian AGO-CLIP data for miRNA-chimeras yielded >17,000 miRNA:target site interactions. Analysis of interactions and extensive experimental validation of chimera-discovered targets of viral miRNAs suggest that our strategy identifies canonical, non-canonical, and non-conserved miRNA interactions. Our data suggest that ~80% of miRNA:targets have perfect or partial seed complementarity. In summary, analysis of miRNA:target chimeras enables the systematic, context-specific, in vivo discovery of miRNA interactions.
2014-05-23 | GSE56180 | GEO
Project description:Expression changes of competitive endogenous RNAs (ceRNAs) have been proposed to influence microRNA (miRNA) activity and thereby regulate other transcripts that contain miRNA binding sites. Here, we find that although miRNA levels define the extent of repression, they do not affect the magnitude of the ceRNA expression change required to observe derepression. Canonical 6-nt sites, which typically mediate modest repression, can nonetheless compete for miRNA binding, with potency ~20% of that observed for canonical 8-nt sites. Sites with extensive additional complementarity can be even more potent, but this occurs predominantly through miRNA degradation rather than competition. Cooperative binding of closely spaced sites for different miRNAs can also increase potency. These results provide quantitative insights into the stoichiometric relationship between miRNA and target abundance, target-site spacing and affinity requirements for ceRNA-mediated gene regulation and specify the unusual circumstances in which ceRNA-mediated gene regulation might be observed. Sixty-four mRNA profiles were generated of 1) primary hepatocytes of mice expressing variable levels of a recombinant Adenovirus expressing the transcript of AldolaseA (Ad-AldoA), containing sites matching miR-122, let-7, miR-192, miR-194 or a mutated site (no site) or 2) embryonic stem (ES) cells that were transfected with a Tet-inducible dual-color reporter construct expressing enhanced yellow fluorescent protein (eYFP) and mCherry that contains zero (0s) or three (3s) 8 nt miRNA seed matches for miR-293 or miR-92 in the 3� UTR. ES cells were sorted with a FACSAria IIIu flow cytometer into three bins based on their eYFP fluorescence intensity. All samples were sequenced in duplicates by an Illumina HiSeq 2500. Library preparation and sequencing were performed by Fasteris SA (Switzerland) or by the Functional Genomics Centre Zürich (FGCZ). Three small RNA profiles or either primary hepatocytes or embryonic stem cells were also generated by Solexa sequencing.
2016-10-27 | E-GEOD-76288 | biostudies-arrayexpress
Project description:To exert regulatory function, miRNAs guide Argonaute (AGO) proteins to partially complementary sites on target RNAs. Crosslinking and immunoprecipitation (“re state-of-the-art to map AGO binding sites, but assigning the targeting miRNA to these sites relies on bioinformatics predictions and is therefore indirect. To directly and unambiguously identify miRNA:target site interactions, we modified our CLIP methodology in C. elegans to experimentally ligate miRNAs to their target sites. Unexpectedly, ligation reactions also occurred in absence of the exogenous ligase. Our in vivo dataset and re-analysis of published mammalian AGO-CLIP data for miRNA-chimeras yielded >17,000 miRNA:target site interactions. Analysis of interactions and extensive experimental validation of chimera-discovered targets of viral miRNAs suggest that our strategy identifies canonical, non-canonical, and non-conserved miRNA interactions. Our data suggest that ~80% of miRNA:targets have perfect or partial seed complementarity. In summary, analysis of miRNA:target chimeras enables the systematic, context-specific, in vivo discovery of miRNA interactions. In vivo PAR-CLIP basically as described previously (Jungkamp et al. 2011) using GFP-tagged ALG-1 expressing worms in L3 stage. Worm lysate was treated with RNase T1. Following immunoprecipitation and a second RNase T1 digest, it was proceeded as described in Hafner et al. 2010. For the modified iPAR-CLIP ligation samples and its control samples immuno-purified complexes were treated with PNK phospathase minus, subjected to ligation with T4 RNA ligase/no ligase added and subsequently phosphorylated with PNK. Protein purification and RNA library preparation essentially as described in Hafner et al., but with the selection of longer RNA products.
2014-05-23 | E-GEOD-56180 | biostudies-arrayexpress
Project description:Among the four Argonaute family members in mammals, only AGO2 protein retains endonuclease activity, and facilitates cleavage of target RNAs base-pairing with highly complementary guide RNAs. Despite the deeply conserved catalytic activity, only a small number of targets have been reported to extensively base pair with cognate miRNAs to be cleaved by AGO2. Here, we analyzed AGO2-bound RNAs by CrossLinking ImmunoPrecipitation (CLIP) of genetically modified cells that express epitope-tagged AGO2 from the native genomic locus. We found that HMGA2 mRNA is cleaved by AGO2 loaded with let-7 and miR-21. In contrast to the generally accepted notion, the base-pairing from the seed region to the cleavage site, rather than perfect or near perfect complementarity, was required for cleavage of the target mRNA in cells. Non-templated addition of nucleotides at the 3’ end of the cleaved RNA was observed, further supporting the AGO2-mediated cleavage. Based on the observation that the limited complementarity is the minimum requirement for cleavage, we found that AGO2-mediated cleavage of targets is more common than previously thought. Our result may explain the vital role of endonuclease activity in controlling miRNA-mediated gene regulation.
2017-10-05 | GSE93644 | GEO
Project description:MicroRNAs are small, non-coding RNAs that post-transcriptionally regulate gene expression by binding to 3âUTRs of target mRNAs. Kaposiâs sarcoma-associated herpesvirus (KSHV), a virus linked to malignancies including primary effusion lymphoma (PEL), encodes 12 miRNA genes, but only a few regulatory targets are known. We found that KSHV-miR-K12-11 shares 100% seed-sequence homology with hsa-miR-155, a miRNA frequently found up-regulated in lymphomas and critically important for B cell development. Based on this seed-sequence homology, we hypothesized that both miRNAs regulate a common set of target genes and as a result, could have similar biological activities. Examination of five PEL lines showed that PELs do not express miR-155, but do express high levels of miR-K12-11. Bioinformatics tools predicted the transcriptional repressor BACH-1 to be targeted by both miRNAs and ectopic expression of either miR-155 or miR-K12-11 inhibited a BACH-1 3'UTR containing reporter. . Furthermore, BACH-1 protein levels are low in cells expressing either miRNA. Gene expression profiling of miRNA-expressing stable cell lines revealed 66 genes that were commonly down-regulated. For select genes, miRNA targeting was confirmed by reporter assays. Thus, based on our in silico predictions, reporter assays, and expression profiling data, miR-K12-11 and miR-155 regulate a common set of cellular targets. Given the role of miR-155 during B cell maturation, we speculate that miR-K12-11 may contribute to the distinct developmental phenotype of PEL cells, which are blocked in a late stage of B cell development. Together, these findings indicate that KSHV miR-K12-11 is an ortholog of miR-155. Experiment Overall Design: 12 samples, 4 experiemental (miR-155 ), 4 experimental (miR-K12-11) and 4 reference controls (pCDNA3.1)
2008-06-16 | E-GEOD-9264 | biostudies-arrayexpress