The dsRBP and inactive editor, ADR-1, utilizes dsRNA binding to regulate A-to-I RNA editing across the C. elegans transcriptome
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ABSTRACT:
ORGANISM(S): Caenorhabditis elegans
PROVIDER: GSE51556 | GEO | 2014/01/20
SECONDARY ACCESSION(S): PRJNA223411
REPOSITORIES: GEO
Similar Datasets
Project description:Purpose: The purpose of this experiment is to expand the repertoire of C. elegans edited transcripts and identify the roles of ADR-1 as indirect regulator of editing and ADR-2 as the only active deaminase in vivo. Methods: Strand-specific RNA sequencing of wild-type and adr mutant worms, followed by a novel RNA variant calling and comparative analysis pipeline. Results: Despite lacking deaminase function, ADR-1 affects editing of over 60 adenosines within the 3’ UTRs of 16 different mRNAs. Furthermore, ADR-1 interacts directly with ADR-2 substrates, even in the absence of ADR-2; and mutations within its dsRNA binding domains abolished both binding and editing regulation. Conclusions: ADR-1 acts as a major regulator of editing by binding ADR-2 substrates in vivo and raises the possibility that other dsRNA binding proteins, including the inactive human ADARs, regulate RNA editing by deaminase-independent mechanisms. Strand-specific RNA sequencing of wild-type and adr mutant worms, followed by a novel RNA variant calling and comparative analysis pipeline.
2014-01-20 | E-GEOD-51556 | biostudies-arrayexpress
Project description:Caenorhabditis elegans strain:N2, adr-1, adr-2, adr-1;adr-2 Transcriptome or Gene expression
| PRJNA82293 | ENA
Project description:Using a combination of molecular and genomic approaches we uncover a molecular mechanism that regulates RNA editing in a neural- and development-specific manner. We de novo identified 570 A-to-i editing sites in adult neural RNA-seq data and 6202 sites from re-analyzing L1 neural RNA seq.Comparing editomes during development led to the identification of both neural transcripts that were edited only in one life-stage. The stage-specific editing is largely regulated by differential gene expression during neural development, and proper gene expression of nearly one-third of these differentially expressed genes is dependent on adr-2, the only known A-to-I editing enzyme in C. elegans. However, we also identified a subset of neural transcripts which are edited and expressed throughout development. Interestingly, despite a neural-specific downregulation of adr-2 during development, the majority of sites edited throughout development exhibit increased editing in adult neural cells. Biochemical data suggests that ADR-1, a deaminase deficient member of the Adenosine deaminase acting on RNA (ADAR) family is competing with ADR-2 for binding to specific transcripts early in development. Our data suggest a model where during neural development, ADR-2 levels overcome ADR-1 repression, resulting in increased ADR-2 binding and editing of specific transcripts. Together, our findings reveal tissue- and development-specific regulation of RNA editing and identify a molecular mechanism that regulates ADAR substrate recognition and editing efficiency.
2020-06-06 | GSE151916 | GEO
Project description:The antiviral defense in vertebrates requires the innate immune system to sense foreign “non-self” nucleic acids while avoiding “self” nucleic acids, which is accomplished by an intricate system. Cellular double-stranded RNAs (dsRNAs) are edited by the RNA editing enzyme ADAR1 to prevent their dsRNA structure pattern from being recognized as viral dsRNA. Lack of RNA editing by ADAR1 enables activation of MDA5, a cytosolic dsRNA sensor, by cellular dsRNA. Additional RNA editing- independent functions of ADAR1 have been proposed, but the specific mechanism remains elusive. Here we demonstrate that RNA binding by ADAR1, independent of its editing activity, restricts the activation of PKR, another cytosolic dsRNA sensor, by cellular dsRNA. Mechanistically, the loss of ADAR1 editing caused MDA5 activation to induce interferon signaling, while a lack of ADAR1 protein or its dsRNA binding ability led to PKR activation, with subsequent stress granule formation and proliferation arrest. Based on these findings we rescued the Adar1−/− mice from embryonic lethality to adulthood by deleting both MDA5 and PKR, in contrast to the limited rescue of Adar1−/− mice by removing MDA5 or PKR alone. Our findings reveal a multifaceted contribution of ADAR1 in regulating the immunogenicity of “self” dsRNAs. Furthermore, ADAR1 is an immuno-oncology target for drug development, and the separation of ADAR1’s RNA editing and binding functions provides mechanistic insights for such developments.
2023-10-03 | GSE198386 | 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:RNA base editors have become powerful tools for both therapeutic and research purposes. However, currently available RNA editors such as ADAR or APOBEC family proteins have limitations due to RNA structure and sequence dependence. Here, we designed a protein engineering platform for putative RNA editor screening and directed enzyme evolution. We engineered an RNA A-to-I base editor (rABE) that has high activity, low local sequence or structure bias, and low background. Utilizing rABE, we present REMORA (RNA Encoded Molecular Recording in Adenosines), a new strategy to measure RNA-binding events on single RNA molecules in cells. In REMORA, adenosine deamination serves as a molecular record of RNA-protein interactions that are identified by mutations by sequencing. By combining our improved A-to-I RNA deaminase with the C-to-U deaminase APOBEC1 and long-read RNA sequencing, our approach enables simultaneous recording of the locations two RNA binding proteins on single mRNA molecules. Orthogonal RNA molecular recording of two Pumilio family proteins, PUM1 and PUM2, reveals that PUM1 competes with PUM2 for some but not all Pumilio binding sites in cells, despite having the same in vitro binding preferences. Our work thus measures competition between RNA-binding proteins for RNA sites in cells, and our genetically encodable RNA deaminase enables single-molecule identification of RNA-protein interactions with cell type specificity.
2022-10-28 | GSE216334 | GEO
Project description:RNA base editors have become powerful tools for both therapeutic and research purposes. However, currently available RNA editors such as ADAR or APOBEC family proteins have limitations due to RNA structure and sequence dependence. Here, we designed a protein engineering platform for putative RNA editor screening and directed enzyme evolution. We engineered an RNA A-to-I base editor (rABE) that has high activity, low local sequence or structure bias, and low background. Utilizing rABE, we present REMORA (RNA Encoded Molecular Recording in Adenosines), a new strategy to measure RNA-binding events on single RNA molecules in cells. In REMORA, adenosine deamination serves as a molecular record of RNA-protein interactions that are identified by mutations by sequencing. By combining our improved A-to-I RNA deaminase with the C-to-U deaminase APOBEC1 and long-read RNA sequencing, our approach enables simultaneous recording of the locations two RNA binding proteins on single mRNA molecules. Orthogonal RNA molecular recording of two Pumilio family proteins, PUM1 and PUM2, reveals that PUM1 competes with PUM2 for some but not all Pumilio binding sites in cells, despite having the same in vitro binding preferences. Our work thus measures competition between RNA-binding proteins for RNA sites in cells, and our genetically encodable RNA deaminase enables single-molecule identification of RNA-protein interactions with cell type specificity.
2023-08-24 | GSE241615 | GEO
Project description:A-to-I RNA editing is widespread in eukaryotic transcriptomes and plays an essential role in the creation of proteomic and phenotypic diversity. Loss of ADARs, the proteins responsible for A-to-I editing, results in lethality in mammals. In C. elegans, knocking out both ADARs, ADR-1 and ADR-2, results in aberrant behavior and abnormal development. Studies have shown that ADR-2 can actively deaminate dsRNA while ADR-1 cannot. However, as most studies of C. elegans ADARs were performed on worms mutated in both ADAR genes, the effects observed cannot be attributed to a single ADAR or to the interactions between ADAR genes. Therefore, we set to study the effects of each C. elegans ADAR on RNA editing, gene expression, protein levels and the contribution of each of ADAR to the phenotypes observed in worms mutated in both genes, in order to elucidate their distinct functions. We found significant differences in the phenotypes observed in worms mutated in a single ADAR gene. Worms harboring adr-1 mutations have a significant reduction in their lifespan, while worms harboring adr-2 mutations have extended lifespan. We also observed severe abnormalities in vulva formation mainly in adr-1 mutants, and we suggest that these phenotypes are a result of an RNA editing independent function of ADR-1. Mutations in each ADAR resulted in expressional changes in hundreds of genes, and a significant downregulation of edited genes. However, very few changes in the protein levels were observed. In addition, we found that ADR-1 binds many edited genes. Our results suggest that ADR-1 has a significant function in the RNA editing process and by altering editing levels it causes the severe phenotypes that we observed. In contrast, a complete lack of RNA editing is less harmful to the worms. Furthermore, our results indicate that the effect of RNA editing on the protein content in the cell is minor and probably the main purpose of these modifications is to antagonize or enhance other gene regulatory mechanisms that act on RNA.
2019-04-22 | GSE110701 | GEO
Project description:Chemoresistance in breast cancer has been a great interest in past studies, however, the development of rational therapeutic strategies targeting chemoresistant cells is still a challenge for clinical oncology.The resistant property of MCF7/ADR cells was confirmed by long term culture with Dox, cell viability, and PARP cleavage assays. Microarray analysis was performed to compare the global differences of gene expression between MCF-7 and MCF-7/ADR cells. MCF-7 and MCF-7/ADR gene expression profiles were analyzed. Total RNA were prepared for analysis with Affymetrix Human U133 Plus 2.0 arrays according to the manufacturerâs instructions.
2016-01-05 | E-GEOD-76540 | biostudies-arrayexpress
Project description:C. elegans mutants deleted for TDP-1, an ortholog of the neurodegeneration-associated RNA binding protein TDP-43, display only mild phenotypes. Nevertheless, transcriptome sequencing revealed that many RNAs were altered in accumulation and/or processing in the mutant. Analysis of these transcriptional abnormalities demonstrates that a primary function of TDP-1 is to limit formation or stability of double-stranded RNA. Specifically, we found that deletion of tdp-1: 1) preferentially alters the accumulation of RNAs with inherent double stranded structure (dsRNA); 2) increases the accumulation of nuclear dsRNA foci, 3) enhances the frequency of adenosine-to-inosine RNA editing, and 4) dramatically increases the amount of transcripts immunoprecipitable with a dsRNA-specific antibody, including intronic sequences, RNAs with antisense overlap to another transcript, and transposons. We also show that TDP-43 knockdown in human cells results in accumulation of dsRNA , indicating that suppression of dsRNA is a conserved function of TDP-43 in mammals. Altered accumulation of structured RNA may account for some of the previously described molecular phenotypes (e.g., altered splicing) resulting from reduction of TDP-43 function. 24 samples: 3 tdp-1 polyA samples with 3 N2 controls, 3 tdp1J2 immunoprecipitated samples and tdp1 total RNA input with 3 N2 J2 immunoprecipitated controls (with N2 input), 3 tdp1 total RNA samples for RNA editing analysis with 3 N2 total RNA controls and an adr-2 mutant control, 2 tdp1 CHIPseq samples with RNAsecontrol.
2014-11-19 | E-GEOD-61581 | biostudies-arrayexpress