Efficient and precise editing of endogenous transcripts with SNAP-tagged ADARs
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE112787 | GEO | 2018/06/01
REPOSITORIES: GEO
Similar Datasets
Project description:Efficient and precise editing of endogenous transcripts with SNAP-tagged ADARs
| PRJNA448951 | ENA
Project description:Circular RNAs (circRNAs) are produced by head-to-tail back-splicing which is mainly facilitated by base-pairing of reverse complementary matches (RCMs) in circRNA flanking introns. Adenosine deaminases acting on RNA (ADARs) are known to bind double-stranded RNAs for adenosine to inosine (A-to-I) RNA editing. Here we characterize ADARs as potent regulators of circular transcriptome by identifying over a thousand of circRNAs regulated by ADARs in a bidirectional manner through and beyond their editing function. We found that editing can stabilize or destabilize secondary structures formed between RCMs via correcting A:C mismatches to I(G)-C pairs or creating I(G).U wobble pairs, respectively. We provided experimental evidence that editing also favors the binding of RNA-binding proteins such as PTBP1 to regulate back-splicing. These ADARs-regulated circRNAs which are ubiquitously expressed in multiple types of cancers, demonstrate high functional relevance to cancer. Our findings support a hitherto unappreciated bidirectional regulation of circular transcriptome by ADARs and highlights the complexity of cross-talk in RNA processing and its contributions to tumorigenesis.
2022-01-25 | GSE164681 | GEO
Project description:Cellular RNAs containing double-stranded RNA (dsRNA) structures are subject to A-to-I RNA editing by the adenosine deaminases that act on RNA (ADARs). While A-to-I editing can alter mRNA coding potential, most editing is observed in non-coding sequences, the function of which remains poorly characterized. To correlate small RNA population with expression patterns of ADARs and hyperedited RNAs (editing-enriched regions: EERs) defined and characterized in a separate RNAseq analysis, we re-analyzed existing smallRNAseq datasets of a wildtype strain and a strain lacking ADARs (adr-1;adr-2). Analysis of primary siRNAs from mixed-stage worms revealed that ADARs impact siRNA biogenesis from EERs. We then analyzed primary and secondary RNAs mapping to EERs from embryo-stage or L4-stage worms and observed that ADAR effects on siRNA levels are dependent on developmental stage.
2018-02-23 | GSE89765 | GEO
Project description:Adenosine deaminases that act on RNA (ADARs) are RNA editing enzymes that convert adenosine to inosine in double-stranded RNA (dsRNA). To evaluate effects of ADARs on small RNAs that derive from dsRNA precursors, we performed deep-sequencing, comparing small RNAs from wildtype and ADAR mutant C. elegans. While editing in small RNAs was rare, at least 40% of microRNAs had altered levels in at least one ADAR mutant strain, and miRNAs with significantly altered levels had mRNA targets with correspondingly affected levels. About 40% of siRNAs derived from endogenous genes (endo-siRNAs) also had altered levels in at least one mutant strain, including 63% of Dicer-dependent endo-siRNAs. The 26G class of endo-siRNAs was significantly affected by ADARs, and many altered 26G loci had intronic reads, and histone modifications associated with transcriptional silencing. Our data indicate ADARs, through both direct and indirect mechanisms, are important for maintaining wildtype levels of many small RNAs in C. elegans. Deep sequencing of small RNAs in wild-type (N2), adr-1 null, adr-2 null and adr-1;adr-2 null mixed stage C. elegans
2012-04-04 | E-GEOD-28888 | biostudies-arrayexpress
Project description:Adenosine deaminases that act on RNA (ADARs) are RNA editing enzymes that convert adenosine to inosine in double-stranded RNA (dsRNA). To evaluate effects of ADARs on small RNAs that derive from dsRNA precursors, we performed deep-sequencing, comparing small RNAs from wildtype and ADAR mutant C. elegans. While editing in small RNAs was rare, at least 40% of microRNAs had altered levels in at least one ADAR mutant strain, and miRNAs with significantly altered levels had mRNA targets with correspondingly affected levels. About 40% of siRNAs derived from endogenous genes (endo-siRNAs) also had altered levels in at least one mutant strain, including 63% of Dicer-dependent endo-siRNAs. The 26G class of endo-siRNAs was significantly affected by ADARs, and many altered 26G loci had intronic reads, and histone modifications associated with transcriptional silencing. Our data indicate ADARs, through both direct and indirect mechanisms, are important for maintaining wildtype levels of many small RNAs in C. elegans.
2012-04-05 | GSE28888 | GEO
Project description:Adenosine deaminases acting on RNA (ADARs) impact diverse cellular processes and pathological conditions. While we possess important insights into their roles in adult tissues, their functions in early cell fate specification remain less understood. To address this, we devised a comprehensive framework to investigate ADARs in human development. We began by charting time-course RNA editing profiles in human organs from fetal to adult stages, enabling broad insights into RNA editing trends across diverse tissues. Next, we utilized hPSC differentiation to experimentally probe ADARs across specific tissue-types, harnessing brain organoids as neural specific, and teratomas as pan-tissue developmental models. We found that time-series teratomas faithfully recapitulated developmental trends observed in fetal tissue. Motivated by this, we conducted pan-tissue, single-cell CRISPR-KO screens of ADARs in teratomas to assess their role in cell-fate specification. Knocking out ADAR1 led to a global decrease in RNA editing across all germ-layers. Intriguingly, we observed a significant fitness defect in mesodermal tissues, and an enrichment of adipogenic cells, revealing a novel role for ADAR1 in mesenchymal differentiation. Collectively, we developed a multi-pronged framework charting time-resolved RNA editing profiles in fetal and fetal-like organ tissues, thereby shedding light on the role of ADARs in development and cell fate-specification.
2024-10-24 | GSE248941 | GEO
Project description:RNA base editing applies endogenous or engineered adenosine deaminases to introduce adenosine-to-inosine changes into a target RNA in a highly programmable manner. Recently, notable success was achieved for the repair of disease-causing guanosine-to-adenosine mutations by means of RNA base editing. Here, we propose that RNA base editing could be broadly applied to perturb protein function by removal of regulatory sites of post-translational modification (PTM), like phosphorylation and/or acetylation sites. We demonstrate the feasibility of PTM interference (PTMi) on more than 70 PTM sites in various signaling proteins and identify key determinants for high editing efficiency and potent down-stream effects. Specifically, we demonstrate both negative and positive regulation of the JAK/STAT pathway by PTMi. To identify potent regulatory sites for PTMi, we applied an improved version of the SNAP-ADAR tool, which achieved high editing efficiency over a broad codon scope with tight control of bystander editing. The transient nature of RNA base editing enables the fast, dose-dependent (thus partial) and reversible manipulation of PTM sites, which is a key advantage over DNA editing approaches, where genetic compensation or lethality can conceal a phenotype. In summary, PTM interference might become a valuable field of application of RNA base editing in basic biology and medicine.
2024-04-19 | GSE264114 | GEO
Project description:Background: Adenosine deaminases that act on RNA (ADARs) bind to double-stranded and structured RNAs and deaminate adenosines to inosines. This A to I editing is widespread and required for normal life and development. Besides mRNAs and repetitive elements, ADARs can target miRNA precursors. Editing of miRNA precursors can affect processing efficiency and alter target specificity. Interestingly, ADARs can also influence miRNA abundance independent of RNA-editing. In mouse embryos where editing levels are low, ADAR2 was found to be the major ADAR protein that affects miRNA abundance. Here we extend our analysis to adult mouse brains where high editing levels are observed. Results: Using Illumina deep sequencing we compare the abundances of mature miRNAs and editing events within them, between wild-type and ADAR2 knockout mice in the adult mouse brain. Reproducible changes in abundance of specific miRNAs are observed in ADAR2 deficient mice. Most of these quantitative changes seem unrelated to A to I editing events. However, many A to G transitions in cDNAs prepared from mature miRNA sequences, reflecting A to I editing events in the RNA, are observed with frequencies reaching up to 80%. About half of these editing events are primarily caused by ADAR2 while a few miRNAs show increased editing in the absence of ADAR2, suggesting preferential editing by ADAR1. Moreover, novel, previously unknown editing events were identified in several miRNAs. In general 64% of all editing events are located within the seed region of mature miRNAs. In one of these cases retargeting of the edited miRNA could be verified in reporter assays. Also, altered processing efficiency upon editing near a processing site could be experimentally verified. Conclusions: ADAR2 can significantly influence the abundance of certain miRNAs in the brain. Only in a few cases changes in miRNA abundance can be explained by miRNA editing. Thus, ADAR2 binding to miRNA precursors, without editing them, may influence their processing and thereby abundance. ADAR1 and ADAR2 have both overlapping and distinct specificities for editing of miRNA editing sites. Over 60% of editing occurs in the seed region possibly changing target specificities for many edited miRNAs. Examination of the effect of ADAR2 on mature miRNA abundance and sequence in adult mouse brain.
2014-10-02 | E-GEOD-61066 | biostudies-arrayexpress
Project description:Adenosine deaminases acting on RNA (ADARs) are involved in adenosine (A) to inosine (I) RNA editing and human ADARs are implicated in neurological diseases. Here we generated human embryonic stem cells (hESCs) lacking ADAR1 to investigate its role in neural development in a human context. We found that ADAR1 deficiency significantly retarded neural induction with widespread mRNA and miRNA expression changes. We have genome widely examined the changes of A-to-I editing and miRNA expression after ADAR1 knockdown. Such aberrant mRNA and miRNA expression was not due to reduced A-to-I editing after ADAR1 knockdown. We further revealed that ADAR1 regulates miRNA biogenesis independent of its editing activity.
2015-03-23 | GSE56152 | GEO
Project description:Background: Adenosine deaminases that act on RNA (ADARs) bind to double-stranded and structured RNAs and deaminate adenosines to inosines. This A to I editing is widespread and required for normal life and development. Besides mRNAs and repetitive elements, ADARs can target miRNA precursors. Editing of miRNA precursors can affect processing efficiency and alter target specificity. Interestingly, ADARs can also influence miRNA abundance independent of RNA-editing. In mouse embryos where editing levels are low, ADAR2 was found to be the major ADAR protein that affects miRNA abundance. Here we extend our analysis to adult mouse brains where high editing levels are observed. Results: Using Illumina deep sequencing we compare the abundances of mature miRNAs and editing events within them, between wild-type and ADAR2 knockout mice in the adult mouse brain. Reproducible changes in abundance of specific miRNAs are observed in ADAR2 deficient mice. Most of these quantitative changes seem unrelated to A to I editing events. However, many A to G transitions in cDNAs prepared from mature miRNA sequences, reflecting A to I editing events in the RNA, are observed with frequencies reaching up to 80%. About half of these editing events are primarily caused by ADAR2 while a few miRNAs show increased editing in the absence of ADAR2, suggesting preferential editing by ADAR1. Moreover, novel, previously unknown editing events were identified in several miRNAs. In general 64% of all editing events are located within the seed region of mature miRNAs. In one of these cases retargeting of the edited miRNA could be verified in reporter assays. Also, altered processing efficiency upon editing near a processing site could be experimentally verified. Conclusions: ADAR2 can significantly influence the abundance of certain miRNAs in the brain. Only in a few cases changes in miRNA abundance can be explained by miRNA editing. Thus, ADAR2 binding to miRNA precursors, without editing them, may influence their processing and thereby abundance. ADAR1 and ADAR2 have both overlapping and distinct specificities for editing of miRNA editing sites. Over 60% of editing occurs in the seed region possibly changing target specificities for many edited miRNAs. Examination of the effect of ADAR2 on gene expression in mature mouse wildtype and ADAR2 knockout brain using AffymetrixM-BM-. GeneChipM-BM-. Whole Transcript (WT) Expression Arrays (Analysis by KFB Regensburg, Germany)
2014-10-02 | E-GEOD-61067 | biostudies-arrayexpress