Argonaute 2 binds directly to tRNA genes and promotes gene repression in cis
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE68813 | GEO | 2015/05/17
SECONDARY ACCESSION(S): PRJNA283872
REPOSITORIES: GEO
Similar Datasets
Project description:To further our understanding of the RNAi machinery within the human nucleus, we analyzed the chromatin and RNA binding of Argonaute 2 (AGO2) within human cancer cell lines. Our data indicated that AGO2 binds directly to nascent tRNA and 5S rRNA, and to the genomic loci from which these RNAs are transcribed, in a small RNA- and DICER-independent manner. AGO2 chromatin binding was not observed at non-TFIIIC-dependent RNA polymerase (Pol) III genes or at extra-TFIIIC (ETC) sites, indicating that the interaction is specific for TFIIIC-dependent Pol III genes. A genome-wide analysis indicated that loss of AGO2 caused a global increase in the mRNA expression level among genes that flank AGO2-bound tRNA genes. This effect was shown to be distinct from that of the disruption of DICER, DROSHA, or CTCF. We propose that AGO2 binding to tRNA genes has a novel and important regulatory role in human cells. ChIP-seq for AGO2 was performed from K562 cells using 2 commercially available monoclonal antibodies (mAbs) and 5 replicates. Replicates 1-3 were performed with Millipore 04-642, and replicates 4 and 5 were performed with Abcam 57113. RNA-seq was carried out on 2 replicates of shMock and 2 replicates of shAGO2. Lentiviral vectors GIPZ Lentiviral #RHS4531-EG271611.
2015-05-17 | E-GEOD-68813 | biostudies-arrayexpress
Project description:Particularly in the context of differentiation and development, the importance of three-dimensional chromatin architecture to gene regulatory mechanisms is becoming increasingly clear. The most ancient known mechanism of chromatin organization involves TFIIIC, a transcription factor (TF) that recruits RNA polymerase III (Pol III) for transcription of tRNA and other types of non-coding RNA genes. From yeast to mammals, TFIIIC binds to tRNA genes (tDNAs) and scattered “extra-TFIIIC” (ETC) loci and serves to tether these loci together as anchors of chromatin loops. TFIIIC activities are modulated by MAF, MYC, and other TF proteins that are still unidentified. Here we identify the ZSCAN5 TF family - including mammalian ZSCAN5B and its primate-specific paralogs - as proteins that occupy mammalian Pol III promoters and ETC sites. We show that ZSCAN5B binds with high specificity to a conserved subset of tDNA loci and other Pol III genes in human and mouse and that primate-specific ZSCAN5A and ZSCAN5D also bind Pol III genes, although ZSCAN5D preferentially localizes to MIR SINE- and LINE2-associated ETC sites. ZSCAN5 genes are expressed in proliferating cell populations and are cell-cycle regulated, and gene expression data suggested that they might cooperate to regulate basic cellular functions including mitotic progression. Consistent with this predicted role, ZSCAN5A knockdown led to increasing numbers of cells in mitotic cells and aneuploidy in cultured cells. Together these data implicate ZSCAN5 genes in regulation of Pol III gene transcription and nearby Pol II genes, ultimately influencing cell cycle progression and differentiation in a variety of tissues.
2017-02-16 | GSE85009 | GEO
Project description:Particularly in the context of differentiation and development, the importance of three-dimensional chromatin architecture to gene regulatory mechanisms is becoming increasingly clear. The most ancient known mechanism of chromatin organization involves TFIIIC, a transcription factor (TF) that recruits RNA polymerase III (Pol III) for transcription of tRNA and other types of non-coding RNA genes. From yeast to mammals, TFIIIC binds to tRNA genes (tDNAs) and scattered “extra-TFIIIC” (ETC) loci and serves to tether these loci together as anchors of chromatin loops. TFIIIC activities are modulated by MAF, MYC, and other TF proteins that are still unidentified. Here we identify the ZSCAN5 TF family - including mammalian ZSCAN5B and its primate-specific paralogs - as proteins that occupy mammalian Pol III promoters and ETC sites. We show that ZSCAN5B binds with high specificity to a conserved subset of tDNA loci and other Pol III genes in human and mouse and that primate-specific ZSCAN5A and ZSCAN5D also bind Pol III genes, although ZSCAN5D preferentially localizes to MIR SINE- and LINE2-associated ETC sites. ZSCAN5 genes are expressed in proliferating cell populations and are cell-cycle regulated, and gene expression data suggested that they might cooperate to regulate basic cellular functions including mitotic progression. Consistent with this predicted role, ZSCAN5A knockdown led to increasing numbers of cells in mitotic cells and aneuploidy in cultured cells. Together these data implicate ZSCAN5 genes in regulation of Pol III gene transcription and nearby Pol II genes, ultimately influencing cell cycle progression and differentiation in a variety of tissues.
2017-02-16 | GSE84884 | GEO
Project description:Particularly in the context of differentiation and development, the importance of three-dimensional chromatin architecture to gene regulatory mechanisms is becoming increasingly clear. The most ancient known mechanism of chromatin organization involves TFIIIC, a transcription factor (TF) that recruits RNA polymerase III (Pol III) for transcription of tRNA and other types of non-coding RNA genes. From yeast to mammals, TFIIIC binds to tRNA genes (tDNAs) and scattered “extra-TFIIIC” (ETC) loci and serves to tether these loci together as anchors of chromatin loops. TFIIIC activities are modulated by MAF, MYC, and other TF proteins that are still unidentified. Here we identify the ZSCAN5 TF family - including mammalian ZSCAN5B and its primate-specific paralogs - as proteins that occupy mammalian Pol III promoters and ETC sites. We show that ZSCAN5B binds with high specificity to a conserved subset of tDNA loci and other Pol III genes in human and mouse and that primate-specific ZSCAN5A and ZSCAN5D also bind Pol III genes, although ZSCAN5D preferentially localizes to MIR SINE- and LINE2-associated ETC sites. ZSCAN5 genes are expressed in proliferating cell populations and are cell-cycle regulated, and gene expression data suggested that they might cooperate to regulate basic cellular functions including mitotic progression. Consistent with this predicted role, ZSCAN5A knockdown led to increasing numbers of cells in mitotic cells and aneuploidy in cultured cells. Together these data implicate ZSCAN5 genes in regulation of Pol III gene transcription and nearby Pol II genes, ultimately influencing cell cycle progression and differentiation in a variety of tissues.
2017-02-16 | GSE85040 | GEO
Project description:RNA polymerase III (RNAP III) synthetizes small essential non-coding RNA molecules such as tRNAs and 5S rRNA. In yeast and vertebrates, RNAP III needs general transcription factors TFIIIA, TFIIIB and TFIIIC to initiate transcription. TFIIIC, composed of six subunits, binds to internal promoter elements in RNAP III-dependent genes. Limited information is available about RNAP III transcription in the trypanosomatid protozoa Trypanosoma brucei and Leishmania major, which diverged early from the eukaryotic lineage. Analyses of the first draft of the trypanosomatid genome sequences failed to recognize orthologs of any of the TFIIIC subunits, suggesting that this transcription factor is absent in these parasites. However, a single putative TFIIIC subunit was recently annotated in the databases. Here we characterize this subunit in T. brucei and L. major and demonstrate that it corresponds to Tau95. In silico analyses showed that both proteins possess the typical Tau95 sequences: the DNA binding region and the dimerization domain. As anticipated for a transcription factor, Tau95 localized to the nucleus in insect forms of both parasites. Chromatin immunoprecipitation (ChIP) assays demonstrated that Tau95 binds to tRNA and U2 snRNA genes in T. brucei. Remarkably, by performing tandem affinity purifications we identified orthologs of TFIIIC subunits Tau55, Tau131 and Tau138 in T. brucei and L. major. Thus, contrary to what was assumed, trypanosomatid parasites do possess a TFIIIC complex. Other putative interacting partners of Tau95 were identified in T. brucei and L. major.
2024-01-16 | PXD045036 | Pride
Project description:The genomic loci occupied by RNA polymerase (pol) III have been characterized in human culture cells by genome-wide chromatin immunoprecipitation experiments followed by deep sequencing (ChIP-Seq). These studies have in particular shown that only about 40 % of the annotated 622 human tRNA genes and pseudogenes are occupied by pol III, and that these genes are often in regions of open chromatin rich in active pol II transcription units. Here we have used ChIP-Seq to characterize pol III-occupied loci in a differentiated tissue, the mouse liver. Our studies define the mouse liver pol III-occupied loci and point to a conserved pol III-occupied mammalian interspersed repeat (MIR) as a potential regulator of a pol III subunit-encoding gene. They reveal that synteny relationships can be established between a number of human and mouse pol III genes, and that the expression levels of these genes are significantly linked. They establish that variations within the A and B promoter boxes, as well as the strength of the terminator sequence can strongly affect pol III occupancy of tRNA genes. They reveal correlations with various genomic features that together describe the pol III occupancy scores over some 50% of tRNA genes. In mouse liver, pol III-occupied loci represented in the NCBI37/mm9 genome assembly comprise fifty 5S genes, fourteen known non-tRNA genes, nine 4.5S genes, and some twenty nine SINEs. In addition, out of the 433 annotated tRNA genes, half are occupied by pol III. Transfer RNA gene expression levels reflect both an underlying genomic organization that is conserved in dividing human culture cells and resting mouse liver cells, and the particular promoter and terminator strengths of individual genes. 12 samples examinded, 4 on pol III, 2 on pol II, 2 on H3K4me3, 2 on H3k36me3, 2 input samples.
2012-01-19 | E-GEOD-33421 | biostudies-arrayexpress
Project description:RNA polymerase III transcribes many noncoding RNAs (e.g. tRNAs) important for translational capacity and other functions. Here, we localized RNA polymerase III, alternative TFIIIB complexes (BRF1/2) and TFIIIC in HeLa cells, determining the Pol III transcriptome, defining gene classes, and revealing ‘TFIIIC-only’ sites. Pol III localization in other transformed and primary cell lines revealed both novel and cell-type specific Pol III loci, and one occupied miRNA. Surprisingly, only a fraction of the in silico-predicted Pol III loci are occupied. Interestingly, many occupied Pol III genes reside within an annotated Pol II promoter. Outside of Pol II promoters, occupied Pol III genes overlap with enhancer-like chromatin and enhancer binding proteins such as ETS1 and STAT1. Remarkably, Pol III occupancy scales with the levels of nearby Pol II, active chromatin and CpG content. Taken together, active promoter and enhancer-like chromatin appears to gate Pol III accessibility to the genome. Use of ChIP-array to identify genomic regions bound by RNA Polymerase III machinery
2010-04-14 | E-GEOD-20609 | biostudies-arrayexpress
Project description:RNA polymerase (Pol) III transcribes many noncoding RNAs (for example, transfer RNAs) important for translational capacity and other functions. We localized Pol III, alternative TFIIIB complexes (BRF1 or BRF2) and TFIIIC in HeLa cells to determine the Pol III transcriptome, define gene classes and reveal 'TFIIIC-only' sites. Pol III localization in other transformed and primary cell lines reveals previously uncharacterized and cell type–specific Pol III loci as well as one microRNA. Notably, only a fraction of the in silico–predicted Pol III loci are occupied. Many occupied Pol III genes reside within an annotated Pol II promoter. Outside of Pol II promoters, occupied Pol III genes overlap with enhancer-like chromatin and enhancer-binding proteins such as ETS1 and STAT1. Moreover, Pol III occupancy scales with the levels of nearby Pol II, active chromatin and CpG content. These results suggest that active chromatin gates Pol III accessibility to the genome.
2010-04-14 | GSE20309 | GEO
Project description:RNA polymerase III transcribes many noncoding RNAs (e.g. tRNAs) important for translational capacity and other functions. Here, we localized RNA polymerase III, alternative TFIIIB complexes (BRF1/2) and TFIIIC in HeLa cells, determining the Pol III transcriptome, defining gene classes, and revealing ‘TFIIIC-only’ sites. Pol III localization in other transformed and primary cell lines revealed both novel and cell-type specific Pol III loci, and one occupied miRNA. Surprisingly, only a fraction of the in silico-predicted Pol III loci are occupied. Interestingly, many occupied Pol III genes reside within an annotated Pol II promoter. Outside of Pol II promoters, occupied Pol III genes overlap with enhancer-like chromatin and enhancer binding proteins such as ETS1 and STAT1. Remarkably, Pol III occupancy scales with the levels of nearby Pol II, active chromatin and CpG content. Taken together, active promoter and enhancer-like chromatin appears to gate Pol III accessibility to the genome.
2010-04-14 | GSE20609 | GEO
Project description:The genomic loci occupied by RNA polymerase (pol) III have been characterized in human culture cells by genome-wide chromatin immunoprecipitation experiments followed by deep sequencing (ChIP-Seq). These studies have in particular shown that only about 40 % of the annotated 622 human tRNA genes and pseudogenes are occupied by pol III, and that these genes are often in regions of open chromatin rich in active pol II transcription units. Here we have used ChIP-Seq to characterize pol III-occupied loci in a differentiated tissue, the mouse liver. Our studies define the mouse liver pol III-occupied loci and point to a conserved pol III-occupied mammalian interspersed repeat (MIR) as a potential regulator of a pol III subunit-encoding gene. They reveal that synteny relationships can be established between a number of human and mouse pol III genes, and that the expression levels of these genes are significantly linked. They establish that variations within the A and B promoter boxes, as well as the strength of the terminator sequence can strongly affect pol III occupancy of tRNA genes. They reveal correlations with various genomic features that together describe the pol III occupancy scores over some 50% of tRNA genes. In mouse liver, pol III-occupied loci represented in the NCBI37/mm9 genome assembly comprise fifty 5S genes, fourteen known non-tRNA genes, nine 4.5S genes, and some twenty nine SINEs. In addition, out of the 433 annotated tRNA genes, half are occupied by pol III. Transfer RNA gene expression levels reflect both an underlying genomic organization that is conserved in dividing human culture cells and resting mouse liver cells, and the particular promoter and terminator strengths of individual genes.
2012-01-19 | GSE33421 | GEO