Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

AGO4 slicer activity reveals the passenger strand function of plant 23 nt siRNAs and the post-slicing retention of target RNAs mediating RNA-directed DNA methylation [smallRNA-seq]

ABSTRACT: In plants, transcriptional silencing by RNA-directed DNA methylation (RdDM) is mediated by ARGONAUTE 4 (AGO4) and 24 nt short-interfering RNAs (siRNAs) that are generated in parallel with 23 nt RNAs of unknown function. We show that 23 nt RNAs serve as the passenger strands of 23/24 nt duplexes loaded into AGO4. The 24 nt siRNAs then guide AGO4 slicing of the passenger strands, generating 11 and 12 nt cleavage products. Unexpectedly, we find that the 12 nt products remain associated with the guide strand-AGO4 complexes. Long noncoding RNAs generated at RdDM loci are similarly sliced and retained by AGO4. These results suggest a model in which RNA POLYMERASE V transcripts at target loci are sliced repeatedly as transcription elongation proceeds, sequentially releasing AGO4-siRNA-scaffold RNA complexes that independently recruit the RdDM machinery. Consistent with this hypothesis, plant lines expressing wild-type versus slicing-defective AGO4 show quantitative variation in cytosine methylation and siRNA levels within RdDM loci.

ORGANISM(S): Arabidopsis thaliana

PROVIDER: GSE201233 | GEO | 2023/02/17

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Shared Molecules

Only show the datasets with similarity scores above: 0.5

Threshold

0.5

Similar Datasets

AGO4 slicer activity reveals the passenger strand function of plant 23 nt siRNAs and the post-slicing retention of target RNAs mediating RNA-directed DNA methylation [WGBS]

Project description:In plants, transcriptional silencing by RNA-directed DNA methylation (RdDM) is mediated by ARGONAUTE 4 (AGO4) and 24 nt short-interfering RNAs (siRNAs) that are generated in parallel with 23 nt RNAs of unknown function. We show that 23 nt RNAs serve as the passenger strands of 23/24 nt duplexes loaded into AGO4. The 24 nt siRNAs then guide AGO4 slicing of the passenger strands, generating 11 and 12 nt cleavage products. Unexpectedly, we find that the 12 nt products remain associated with the guide strand-AGO4 complexes. Long noncoding RNAs generated at RdDM loci are similarly sliced and retained by AGO4. These results suggest a model in which RNA POLYMERASE V transcripts at target loci are sliced repeatedly as transcription elongation proceeds, sequentially releasing AGO4-siRNA-scaffold RNA complexes that independently recruit the RdDM machinery. Consistent with this hypothesis, plant lines expressing wild-type versus slicing-defective AGO4 show quantitative variation in cytosine methylation and siRNA levels within RdDM loci.

2023-02-17 | GSE201234 | GEO

RNA-directed DNA methylation involves co-transcriptional small RNA-guided slicing of Pol V transcripts in Arabidopsis.

Project description:Small RNAs regulate chromatin modifications such as DNA methylation and gene silencing across eukaryotic genomes. In plants, RNA-directed DNA methylation (RdDM) requires 24-nucleotide (nt) small RNAs (siRNAs) that bind ARGONAUTE4 (AGO4) and target genomic regions for silencing. It also requires non-coding RNAs transcribed by RNA POLYMERASE V (Pol V), that likely serve as scaffolds for binding of AGO4/siRNA complexes. Here we utilized a modified global nuclear run-on (GRO) protocol followed by deep sequencing to capture Pol V nascent transcripts genome-wide. We uncovered unique characteristics of Pol V RNAs, including a uracil (U) common at position 10. This uracil was complementary to the 5’ adenine found in many AGO4-bound 24-nt siRNAs and was eliminated in an siRNA-deficient mutant as well as in the ago4/6/9 triple mutant, suggesting that the +10U signature is due to siRNA-mediated co-transcriptional slicing of Pol V transcripts. Expressing wild-type AGO4 in ago4/6/9 was able to restore slicing of Pol V transcripts but a catalytically inactive AGO4 mutant did not correct the slicing defect. We also found that Pol V transcript slicing required the little understood elongation factor SPT5L. These results highlight the importance of Pol V transcript slicing in RNA-mediated transcriptional gene silencing, which is a conserved process in many eukaryotes.

2018-01-29 | GSE108078 | GEO

RNA-directed DNA methylation involves co-transcriptional small RNA-guided slicing of Pol V transcripts in Arabidopsis

Project description:Small RNAs regulate chromatin modifications such as DNA methylation and gene silencing across eukaryotic genomes. In plants, RNA-directed DNA methylation (RdDM) requires 24-nucleotide (nt) small RNAs (siRNAs) that bind ARGONAUTE4 (AGO4) and target genomic regions for silencing. It also requires non-coding RNAs transcribed by RNA POLYMERASE V (Pol V), although their function is largely unknown. We utilized a modified global nuclear run-on (GRO) protocol followed by deep sequencing to capture Pol V nascent transcripts genome-wide. We uncovered unique characteristics of Pol V RNAs, including a uracil (U) common at position 10. This uracil was complementary to the 5’ adenine found in many AGO4-bound 24-nt siRNAs and was eliminated in an siRNA-deficient mutant. This indicates co-transcriptional slicing of Pol V transcripts by AGO4-bound siRNAs. Pol V transcript slicing also required the elongation factor SPT5L. These results highlight a novel step in RNA-mediated transcriptional gene silencing, which is a conserved process in many eukaryotes.

2018-01-29 | GSE100010 | GEO

Expression data from 5-week-old Arabidopsis

Project description:AGO4 plays an important role in RNA-directed DNA methylation (RdDM). RdDM on specific genomic loci have the potential to silence the nearby protein coding gene. We used wild-type La-er and ago4-1 mutant Arabidopsis to identify AGO4-regulated genes. Five-weeks wild-type and ago4-1 mutant RNA were used for Affymetrix microarrays. Differentially expressed genes were identified to study the role of AGO4 in regulating plant development.

2010-12-20 | E-GEOD-18928 | biostudies-arrayexpress

Expression data from 5-week-old Arabidopsis

2010-12-20 | GSE18928 | GEO

Arabidopsis AGO3 predominantly recruits 24-nucleotide small RNAs to regulate epigenetic silencing [miRNA-seq]

Project description:AGO3 predominantly bound 24-nt sRNAs with 5â?? terminal adenine. The spectrum of AGO3-associated sRNAs was different from those bound to AGO2. By contrast, approximately 30% of AGO3-bound 24-nt sRNAs overlapped with those bound to AGO4 and over 60% of AGO3-associated 24-nt sRNA enriched loci were identical to those of AGO4. In addition, expression of AGO3 driven by AGO4 native promoter partially complemented AGO4 function and rescued DNA methylation defect in ago4-1 background. Examination of AGO3 and AGO2 bound small RNAs with/without salt stress.

2016-05-31 | E-GEOD-78088 | biostudies-arrayexpress

AGO4 slicer activity reveals the passenger strand function of plant 23 nt siRNAs and the post-slicing retention of target RNAs mediating RNA-directed DNA methylation [WGBS]

Project description:AGO4 slicer activity reveals the passenger strand function of plant 23 nt siRNAs and the post-slicing retention of target RNAs mediating RNA-directed DNA methylation [WGBS]

| PRJNA830474 | ENA

AGO4 slicer activity reveals the passenger strand function of plant 23 nt siRNAs and the post-slicing retention of target RNAs mediating RNA-directed DNA methylation [smallRNA-seq]

Project description:AGO4 slicer activity reveals the passenger strand function of plant 23 nt siRNAs and the post-slicing retention of target RNAs mediating RNA-directed DNA methylation [smallRNA-seq]

| PRJNA830475 | ENA

RNA polymerase V targets transcriptional silencing components to promoters of protein-coding genes

Project description:Transcriptional gene silencing controls transposons and other repetitive elements through RNA-directed DNA methylation (RdDM) and heterochromatin formation. A key component of the Arabidopsis RdDM pathway is ARGONAUTE4 (AGO4), which associates with sizs to mediate DNA methylation. Here, we show that AGO4 preferentially targets transposable elements embedded within promoters of protein-coding genes. This pattern of AGO4 binding cannot be simply explained by the sequences of AGO4-bound siRNAs; instead, AGO4 binding to specific gene promoters is also mediated by long non-coding RNAs (lncRNAs) produced by RNA polymerase V. lncRNA-mediated AGO4 binding to gene promoters directs asymmetric DNA methylation to these genomic regions and is involved in regulating the expression of targeted genes. Finally, AGO4 binding overlaps sites of DNA methylation affected by the biotic stress response. Based on these findings, we propose that the targets of AGO4-directed RdDM are regulatory units responsible for controlling gene expression under specific environmental conditions. ChIP-seq experiments using AGO4 antibody of WT (Col-0) and ago4 or nrpe1 mutant plants of Arabidopsis thaliana

2012-10-17 | E-GEOD-35381 | biostudies-arrayexpress

Arabidopsis AGO3 predominantly recruits 24-nucleotide small RNAs to regulate epigenetic silencing [Bisulfite-seq]

Project description:AGO3 predominantly bound 24-nt sRNAs with 5’ terminal adenine. The spectrum of AGO3-associated sRNAs was different from those bound to AGO2. By contrast, approximately 30% of AGO3-bound 24-nt sRNAs overlapped with those bound to AGO4 and over 60% of AGO3-associated 24-nt sRNA enriched loci were identical to those of AGO4. In addition, expression of AGO3 driven by AGO4 native promoter partially complemented AGO4 function and rescued DNA methylation defect in ago4-1 background.

2016-05-31 | GSE78089 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data