Role of 3' UTR in spreading of siRNAs
Ontology highlight
ABSTRACT:
ORGANISM(S): Schizosaccharomyces pombe
PROVIDER: GSE52534 | GEO | 2013/12/26
SECONDARY ACCESSION(S): PRJNA229168
REPOSITORIES: GEO
Similar Datasets
Project description:We use small RNA sequencing to look for spreading of secondary and tertiary siRNAs along transcripts targeted by ectopic hairpin-derived primary siRNAs. We find that signals within the 3' UTR inhibit siRNA spreading. sequencing of 20-30nt sRNAs from Argonaute immunoprecipitation
2013-12-26 | E-GEOD-52534 | biostudies-arrayexpress
Project description:We tested the ability of trans siRNAs to establish a silent allele of endogenous ade6+ or an ade6+ transgene inserted within euchromatic loci. We found that a silent ade6-OFF epi-allele that grows red on low adenine medium could be established in several mutant backgrounds (mlo3∆, leo1∆) in the presence of ectopic siRNAs. Furthermore, we found that the silent ade6-OFF epi-allele could be meiotically inherited to wildtype progeny lacking the establishing mutation or ectopic siRNAs. Here, we sequenced genome-wide small RNAs and found widespread generation of secondary siRNAs at genes surrounding the ade6-OFF locus in cells expressing the ectopic siRNAs source cen::ade6. In wildtype meiotic progeny lacking the driver cen::ade6 siRNAs, we observed establishment of a local siRNA producing locus at genes adjacent to the endogenous ade6-OFF or at a kanMX-ade6-OFF transgene inserted within euchromatic loci. In contrast, spreading of secondary siRNAs was limited or nonexistent in ade6-ON cells. Finally, we found that spreading of secondary siRNAs at the endogenous ade6 locus was limited when an ade6 hairpin construct served as the ectopic siRNA driver locus instead of cen::ade6.
2018-04-26 | GSE111858 | GEO
Project description:We tested the ability of trans siRNAs to establish a silent allele of endogenous ade6+ or an ade6+ transgene inserted within euchromatic loci. We found that a silent ade6-OFF epi-allele that grows red on low adenine medium could be established in several mutant backgrounds (mlo3∆, leo1∆) in the presence of ectopic siRNAs. Furthermore, we found that the silent ade6-OFF epi-allele could be meiotically inherited to wildtype progeny lacking the establishing mutation or ectopic siRNAs. Here, we sequenced genome-wide DNA associated with conserved heterochromatin markers and found that silencing of the endogenous ade6 locus correlates with increased spreading of H3K9me2 and H3K9me3. Additionally, heterochromatin domains established with cen::ade6 as the ectopic siRNA-producing locus were associated with significantly more spreading of H3K9me2 and H3K9me3 than those established using an ade6 hairpin as the driver siRNA-producing locus.
2018-04-26 | GSE111851 | GEO
Project description:Role of 3' UTR in spreading of siRNAs
| PRJNA229168 | ENA
Project description:We analyzed the C. elegans small RNA response to high copy transgene sequences expressed in the soma in a wild type and an eri-6/7 mutant background. We also analyzed small RNA defects in the arl-8(tm2472) mutant. Transgene siRNAs are 22 nt long, mostly antisense, and correspond to the promoter, coding regions, the 3'UTR and plamsid sequences present on the transgene. Transgene siRNAs are decreased in the eri-6/7 mutant. In the arl-8 mutant, 26G siRNAs in the ALG-3/4 dependent endogenous RNAi pathway are decreased.
2013-12-15 | GSE52785 | GEO
Project description:We analyzed the C. elegans small RNA response to high copy transgene sequences expressed in the soma in a wild type and an eri-6/7 mutant background. We also analyzed small RNA defects in the arl-8(tm2472) mutant. Transgene siRNAs are 22 nt long, mostly antisense, and correspond to the promoter, coding regions, the 3'UTR and plamsid sequences present on the transgene. Transgene siRNAs are decreased in the eri-6/7 mutant. In the arl-8 mutant, 26G siRNAs in the ALG-3/4 dependent endogenous RNAi pathway are decreased. Sequencing small RNAs from C. elegans transgenic strains and mutants.
2013-12-15 | E-GEOD-52785 | biostudies-arrayexpress
Project description:Despite their prominent role in transposon silencing, expression of endo-siRNAs is not limited to the “non-self” DNA elements. Transcripts of protein-coding genes (“self” DNA) in some cases also produce endo-siRNAs in yeast, plants, and animals [1]. How cells distinguish these two populations of siRNAs to prevent unwanted silencing of self-genes in animals is not well understood. To address this question, we examined the expression of ectopic siRNAs from an LTR retrotransposon in C. elegans germline. We found that the abundance of ectopic siRNAs was dependent on their homologous target genes: ectopic siRNAs against genes expressed only in somatic cells can be abundantly expressed. In contrast, ectopic siRNAs against germline-expressed genes are often suppressed. This phenomenon, which we termed “target-directed siRNA suppression”, is dependent on the target mRNA and requires germline P-granule components. We found that siRNA suppression can also occur to naturally produced endo-siRNAs. We suggest that siRNA suppression plays an important role in regulating siRNA expression and preventing self-genes from aberrant epigenetic silencing.
2022-02-19 | GSE196847 | GEO
Project description:In the nematode Caenorhabditis elegans, different small RNA-dependent gene silencing mechanisms act in the germline to initiate transgenerational gene silencing. Piwi-interacting RNAs (piRNAs) can initiate transposon and gene silencing by acting upstream of endogenous short interfering RNAs (siRNAs), which engage a nuclear RNA interference (RNAi) pathway to trigger transcriptional gene silencing. Once gene silencing has been established, it can be stably maintained over multiple generations without the requirement of the initial trigger and is also referred to as RNAe or paramutation. This heritable silencing depends on the integrity of the nuclear RNAi pathway. However, the exact mechanism by which silencing is maintained across generations is not understood.Here we demonstrate that silencing of piRNA targets involves the production of two distinct classes of small RNAs with different genetic requirements. The first class, secondary siRNAs, are localized close to the direct target site for piRNAs. Nuclear import of the secondary siRNAs by the Argonaute HRDE-1 leads to the production of a distinct class of small RNAs that map throughout the transcript, which we term tertiary siRNAs. Both classes of small RNAs are necessary for full repression of the target gene and can be maintained independently of the initial piRNA trigger. Consistently, we observed a form of paramutation associated with tertiary siRNAs. Once paramutated, a tertiary siRNA generating allele confers dominant silencing in the progeny regardless of its own transmission, suggesting germline-transmitted siRNAs are sufficient for multigenerational silencing. C. elegans strains containing transgenes silenced by piRNAs were crossed to strains with transgenes with similar sequences but without piRNA target sites, to investigate the spreading of silencing between transgenes mediated by small RNAs. Mutant backgrounds were used to investigate the genetic requirements for this process.
2015-04-01 | E-GEOD-66344 | biostudies-arrayexpress
Project description:Canonical small interfering RNAs (siRNAs) are generated by the cleavage of double-stranded RNA (dsRNA) by the ribonuclease Dicer. siRNAs are found in plants, animals, and some fungi where they bind to Argonautes to direct RNA silencing. In this study, we characterized the canonical Dicer-dependent siRNAs of C. elegans. We identified thousands of endogenous loci, representing dozens of unique elements, that give rise to low to moderate levels of siRNAs, called 23H-RNAs. These loci include repetitive elements, alleged coding genes, pseudogenes, non-coding RNAs, and unannotated features, many of which adopt hairpin structures. Using protein-small RNA co-immunoprecipitation, we identified the Argonautes that associate with 23H-RNAs and using mRNA-sequencing we explored their roles in gene regulation.
2024-01-29 | GSE254442 | GEO
Project description:LAPTM5 3’UTR suppresses the growth of B-lymphoma cells. To investigate the underline mechanism, we used the Agilent Whole Mouse Genome Microarray 4×44K to profile the differential expressed genes. Ectopic expression of LAPTM5 3’UTR in B-lymphoma cells 38B9 led to upregulation of 225 genes and downregulation of 350 genes with a 2-fold or greater changes compare with empty vector control cells.
2020-02-19 | GSE145463 | GEO