Precipitation of mRNAs by Ago2 and phosphorylation mutants
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE92698 | GEO | 2017/06/22
SECONDARY ACCESSION(S): PRJNA358393
REPOSITORIES: GEO
Similar Datasets
Project description:Small regulatory RNAs including small interfering RNAs (siRNAs) and microRNAs (miRNAs) guide Argonaute (Ago) proteins to specific target RNAs leading to mRNA destabilization or translational repression. We recently reported the identification of Importin 8 (Imp8) as a novel component of miRNA-guided regulatory pathways. Imp8 interacts with Ago proteins and localizes to cytoplasmic processing bodies (P-bodies), structures involved in RNA metabolism. For this micro-array dataset, we used immunoprecipitations of Ago2-associated mRNAs followed by micro-array analysis. The results demonstrate that Imp8 is required for recruiting Ago protein complexes to a large set of Ago2-associated target mRNAs allowing for efficient and specific gene silencing. Therefore, we provide evidence that Imp8 is required for cytoplasmic miRNA-guided gene silencing.
2009-01-22 | GSE14054 | GEO
Project description:Transcription and pre-mRNA alternative splicing are highly regulated processes that play major roles in modulating eukaryotic gene expression. It is increasingly apparent that other pathways of RNA metabolism, including small RNA biogenesis, can regulate these processes. However, a direct link between alternative pre- mRNA splicing and small RNA pathways has remained elusive. Here we show that the small RNA pathway protein Argonaute-2 (Ago-2) regulates alternative pre-mRNA splicing patterns of specific transcripts in the Drosophila nucleus using genome-wide methods in conjunction with RNAi in cell culture and Ago-2 deletion or catalytic site mutations in Drosophila adults. Moreover, we show that nuclear Argonaute-2 binds to specific chromatin sites near gene promoters and negatively regulates the transcription of the Ago-2-associated target genes. These transcriptional target genes are also bound by Polycomb group (PcG) transcriptional repressor proteins and change during development, implying that Ago-2 may regulate Drosophila development. Impor- tantly, both of these activities were independent of the catalytic activity of Ago-2, suggesting new roles for Ago-2 in the nucleus. Finally, we determined the nuclear RNA-binding profile of Ago-2, found it bound to several splicing target transcripts, and identified a G-rich RNA-binding site for Ago-2 that was enriched in these transcripts. These results suggest two new nuclear roles for Ago-2: one in pre-mRNA splicing and one in transcriptional repression. 2 Ago2 mutants, 51B and V966M, heterozygotes and homozygotes of both each sequenced in duplicate
2013-09-25 | E-GEOD-51136 | biostudies-arrayexpress
Project description:Argonaute (Ago) proteins interact with various binding partners and play a pivotal role in microRNA (miRNA)-mediated silencing pathways. By utilizing immunoprecipitation followed by mass spectrometry to determine cytoplasmic Ago2 protein complexes in mouse embryonic stem cells (mESCs), we identified a putative RNA-binding protein FAM120A (also known as OSSA/C9ORF10) as an Ago2 interacting protein. Individual nucleotide resolution Cross-Linking and ImmunoPrecipitation (iCLIP) analysis revealed that FAM120A binds to homopolymeric tracts in 3´ UTRs of about 2,000 mRNAs, particularly poly(G) sequences. Comparison of FAM120A iCLIP and Ago2 iCLIP reveals that greater than one-third of mRNAs bound by Ago2 in mESCs are co-bound by FAM120A. Furthermore, such FAM120A-bound Ago2 target genes are not subject to Ago2-mediated target degradation. Reporter assays suggest that the 3´ UTRs of several FAM120A-bound miRNA target genes are less sensitive to Ago2-mediated target repression than those of FAM120A-unbound miRNA targets and FAM120A modulates them via its G-rich target sites. These findings suggest that Ago2 may exist in multiple protein complexes with varying degrees of functionality.
2019-07-09 | GSE128264 | GEO
Project description:We undertook an unbiased approach based on differential Argonaute-2 (Ago2) RNA immunoprecipitation followed by deep sequencing (Ago2 RIP-seq) to unravel the molecular mechanism(s) underlying miR-146a function, namely the relevant mRNA target(s). Ago2 is a crucial protein that engages with both miRNA and its mRNA target(s) in the RISC complex. To overcome the problem of lack of commercially available high affinity antibodies against Ago2, we took advantage of a genetically modified mouse in which endogenous Ago2 is replaced with a N-terminal tagged version of the protein (3xFLAG- 6xHIS), thus allowing stringent purification (i.e., with low unspecific background) of the RNA molecules bound to Ago2 (upon UV-crosslinking), followed by RNA-sequencing. In order to enrich for miR-146a targets, we transduced purified CD3+ T cells (we could not use γδ T cells due to insufficient cell numbers for this approach) with a miR-146a-expressing retrovirus (with~12-fold overexpression of miR-146a). We thereby identified 225 putative mRNAs after differential Ago2-RIP-seq, from which 96 (42,7%) had a predicted miR-146a binding site in their 3’ UTR region.
2018-02-12 | GSE109263 | GEO
Project description:Transcription and pre-mRNA alternative splicing are highly regulated processes that play major roles in modulating eukaryotic gene expression. It is increasingly apparent that other pathways of RNA metabolism, including small RNA biogenesis, can regulate these processes. However, a direct link between alternative pre- mRNA splicing and small RNA pathways has remained elusive. Here we show that the small RNA pathway protein Argonaute-2 (Ago-2) regulates alternative pre-mRNA splicing patterns of specific transcripts in the Drosophila nucleus using genome-wide methods in conjunction with RNAi in cell culture and Ago-2 deletion or catalytic site mutations in Drosophila adults. Moreover, we show that nuclear Argonaute-2 binds to specific chromatin sites near gene promoters and negatively regulates the transcription of the Ago-2-associated target genes. These transcriptional target genes are also bound by Polycomb group (PcG) transcriptional repressor proteins and change during development, implying that Ago-2 may regulate Drosophila development. Impor- tantly, both of these activities were independent of the catalytic activity of Ago-2, suggesting new roles for Ago-2 in the nucleus. Finally, we determined the nuclear RNA-binding profile of Ago-2, found it bound to several splicing target transcripts, and identified a G-rich RNA-binding site for Ago-2 that was enriched in these transcripts. These results suggest two new nuclear roles for Ago-2: one in pre-mRNA splicing and one in transcriptional repression. Input chromatin, 2 replicates of Ago2 ChIP-seq
2013-09-25 | E-GEOD-51134 | biostudies-arrayexpress
Project description:Background: The RNA-binding protein Argonaute 2 (AGO2) is a key effector of RNAsilencing pathways, exerting a pivotal role in microRNA maturation and activity, that in the cell nucleus is able to modulate chromatin remodeling, transcriptional gene regulation and RNA splicing. The Estrogen Receptor beta (ERβ), a member of the nuclear receptor superfamily of trancriptional regulators, is endowed with oncosuppressive activities, antagonizing hormone-induced carcinogenesis and inhibiting growth and oncogenic functions in luminal-like breast cancers (BCs), where its expression correlates with a better prognosis of the disease. Results: Applying interaction proteomics coupled to mass spectrometry (MS) to characterize nuclear factors cooperating with ERβ in gene regulation, we identified AGO2 as a novel partner of ERβ in human BC cells. ERβ-AGO2 association was confirmed in vitro and in vivo both in the nucleus and cytoplasm. ChIP-Seq demonstrated AGO2 association to a large number of ERβ binding sites, and total and nascent RNA-Seq in ERβ+ vs ERβ- cells, and before and after AGO2 knock-down in ERβ+ cells, revealed a widespread involvement of this factor in ERβ-mediated regulation of gene transcription rate and RNA splicing. Moreover, isolation and sequencing by RIP-Seq of ERβ-associated long and small RNAs in the cytoplasm suggested involvement of the nuclear receptor in RISC loading, indicating that it may able to control directly also mRNA translation efficiency and stability. Conclusions: These results demonstrate that AGO2 is a pleiotropic functional partner of ERβ in BC cells, indicating that both factors are endowed with multiple roles in the control of BC cell functions.
2017-09-20 | PXD006280 | Pride
Project description:To determine the spectrum of miRNA targets regulated following Dicer deletion, we performed argonaute 2 (AGO2)-RNA Immunoprecipitation (RIP)-microarray in bone marrow-derived macrophages (BMDMs) from LysM-Cre/Dicerflox/flox/Apoe–/– and LysM-Cre/Dicerwt/wt/Apoe–/– mice. This analysis combined with miRNA profiling in Dicer wild type (WT) and knockout (KO) BMDMs may help to identify the miRNA targets regulated by Dicer deletion.
2018-05-23 | GSE87717 | GEO
Project description:Shortening of polyadenosine (poly(A)) tails (deadenylation) is the initial step in the decay of most mRNAs. The CCR4-NOT complex is the major deadenylase in mammals. Interaction of Cnot1 with RNA binding proteins, including the miRNA-induced silencing complex (miRISC), which includes Argonaute (Ago) and GW182 as core proteins, and the TTP family of AU-rich element (ARE)-binding proteins (TTP and BRF1/2), recruits the CCR4-NOT complex to the 3’-untranslated regions (3’-UTR) of mRNAs, leading to their degradation. This experiment aimed to determine the binding affinity of the CCR4-NOT complex, Ago2, and BRF1 with their target mRNAs in liver. Liver isolated from C57BL/6J wild-type mice at 8 weeks of age was solubilized in TNE buffer for 30 min at 4ºC. Lysate was incubated with antibodies against Cnot3, Ago2, and BRF1 for 1 hr at 4ºC, and then incubated with Dynabeads (Invitrogen) for 2 hr at 4ºC. mRNAs in immune complexes were isolated using Isogen II. 100 ng of total RNA was used for RNA-seq library preparation with TruSeq Stranded mRNA Library Prep Kit for NeoPrep. 150 base-pair pair-end read RNA-seq was performed with Hiseq 3000/4000 PE Cluster Kit and Hiseq 3000/4000 SBS Kit on Hiseq4000.
2020-03-30 | E-MTAB-6941 | biostudies-arrayexpress
Project description:In mammals, RNA interference (RNAi) is mostly studied as a cytoplasmic event, however, numerous reports convincingly show nuclear localization of the AGO proteins. Nevertheless, the mechanism of nuclear entry remains to be fully elucidated, and the extent of nuclear RNAi further explored. We found that reduced Lamin A levels significantly induced nuclear influx of AGO2 in SHSY5Y neuroblastoma and A375 melanoma cancer cell lines, which normally have no nuclear AGO2. The translocation of AGO2 was accompanied by aggravated cell proliferation and we further found that the loss of Lamin A leads to EGFR and Src kinase activation, which regulates the turnover and stability of cytoplasmic AGO2. Furthermore, Lamin A KO significantly reduced the activity of nuclear RNAi. This was evident by AGO fPAR-CLIP in WT and Lamin A KO cells, where we observed ca 60% less efficiency of RNAi. Mass spectrometry of AGO interactome, from the nuclear fraction, indicated that AGO2 is in complex with FAM120A, a known interactor of AGO2 that reduces the activity of RNAi by competing with AGO2 transcript binding. Therefore, loss of Lamin A starts a signaling cascade that mediates nuclear AGO2 translocation to rapidly inhibit RNAi in order to facilitate cancer proliferation
2024-10-17 | PXD042899 | Pride
Project description:As a core RISC component, Ago2 associates with miRNAs and target mRNAs. To identify these mRNAs, we ran lysate from HEK293T cells over a FLAG resin from 2 conditions: +FLAG-Ago2, +mock transfection. To identify mRNAs associated with specific miRNAs, we ran lysate from HEK293T cells over a FLAG resin from 2 conditions: +FLAG-Ago2 & miR-1, and +FLAG-Ago2 & miR-124. Set of arrays that are part of repeated experiments Compound Based Treatment: mock transfected Keywords: Biological Replicate
2008-04-08 | GSE11079 | GEO