Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Reinforcement of transcriptional silencing by a positive feedback between DNA methylation and non-coding transcription

ABSTRACT: Non-coding transcription is an important determinant of heterochromatin formation. In Arabidopsis thaliana a specialized RNA polymerase V (Pol V) transcribes pervasively and produces long non-coding RNA. This facilitates locus-specific establishment of RNA-directed DNA methylation (RdDM). Subsequent maintenance of RdDM is associated with elevated levels of Pol V transcription, which is consistent with a mutual reinforcement of DNA methylation and non-coding transcription. However, the impact of DNA methylation on Pol V transcription remained unresolved. We found that loss of DNA methylation leads to a strong reduction of Pol V transcription. This occurs when DNA methylation is lost in all sequence contexts, which may happen not only in mutants defective in RdDM but also in mutants lacking maintenance DNA methyltransferases. Our results support a model where RdDM is maintained by a mutual reinforcement of DNA methylation and Pol V transcription with a strong crosstalk with other silencing pathways.

ORGANISM(S): Arabidopsis thaliana

PROVIDER: GSE168869 | GEO | 2021/08/27

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

A conserved Pol II elongator SPT6L mediates Pol V transcription to regulate RNA-directed DNA methylation in Arabidopsis

Project description:In plants, the plant-specific RNA polymerase V (Pol V) transcripts non-coding RNA and provides a docking platform for the association of accessory proteins in the RNA-directed DNA methylation (RdDM) pathway. Various components were uncovered in the process of DNA methylation, but it is still not clear how the transcription of Pol V is regulated. Here, we found the conserved elongation factor, SPT6L, bound to thousands of intergenic regions in an RNA polymerase II (Pol II) independent manner. The intergenic enrichment of SPT6L, interestingly, co-occupied with the largest subunit of Pol V (NRPE1) and the mutation of SPT6L led to the reduction of DNA methylation but not Pol V enrichment. Furthermore, the association of SPT6L at Pol V loci was dependent on the Pol V associated factor, SPT5L, rather than the presence of Pol V, and the interaction between SPT6L and NRPE1 was compromised in spt5l. Finally, Pol V RIP-seq revealed that SPT6L is required to maintain the amount and length of Pol V transcripts. Our findings revealed the critical role of a Pol II conserved elongation factor in Pol V mediated DNA methylation and transcription, and shed light on the mutual regulation between Pol V and Pol II in plants.

2024-04-22 | GSE233781 | GEO

Reinforcement of transcriptional silencing by a positive feedback between DNA methylation and non-coding transcription

Project description:Reinforcement of transcriptional silencing by a positive feedback between DNA methylation and non-coding transcription

| PRJNA714396 | ENA

DNA Topoisomerase 1a Promotes RNA-directed DNA Methylation and Histone Lysine 9 Dimethylation at Transposable Elements in Arabidopsis [RNA-Seq]

Project description:RNA-directed DNA methylation (RdDM) is a transcriptional silencing mechanism mediated by small and long noncoding RNAs produced by the plant-specific RNA polymerases Pol IV and Pol V, respectively. Through a chemical genetics screen with a luciferase-based DNA methylation reporter, LUCL, we found that camptothecin, a compound with anti-cancer properties that targets DNA topoisomerase 1a (TOP1a) was able to de-repress LUCL by reducing its DNA methylation and H3K9 dimethylation (H3K9me2) levels. Further studies with Arabidopsis top1a mutants showed that TOP1a promotes RdDM by facilitating the production of Pol V-dependent long non-coding RNAs, AGONAUTE4 recruitment and H3K9me2 deposition at transposable elements (TEs). 5 small RNA libraries were sequenced

2014-07-08 | E-GEOD-50719 | biostudies-arrayexpress

DNA Topoisomerase 1M-NM-1 Promotes RNA-directed DNA Methylation and Histone Lysine 9 Dimethylation at Transposable Elements in Arabidopsis [Bisulfite-Seq]

Project description:RNA-directed DNA methylation (RdDM) is a transcriptional silencing mechanism mediated by small and long noncoding RNAs produced by the plant-specific RNA polymerases Pol IV and Pol V, respectively. Through a chemical genetics screen with a luciferase-based DNA methylation reporter, LUCL, we found that camptothecin, a compound with anti-cancer properties that targets DNA topoisomerase 1M-NM-1 (TOP1M-NM-1) was able to de-repress LUCL by reducing its DNA methylation and H3K9 dimethylation (H3K9me2) levels. Further studies with Arabidopsis top1M-NM-1 mutants showed that TOP1M-NM-1 promotes RdDM by facilitating the production of Pol V-dependent long non-coding RNAs, AGONAUTE4 recruitment and H3K9me2 deposition at transposable elements (TEs). ten bisufite libraries were sequenced

2014-07-07 | E-GEOD-50691 | biostudies-arrayexpress

The MOM1 complex recruits the RdDM machinery via MORC6 to establish de novo DNA methylation.

Project description:MOM1 is an Arabidopsis factor previously shown to mediate transcriptional silencing independent of major DNA methylation changes. Here we found that MOM1 localizes with sites of RNA-directed DNA methylation (RdDM). Tethering MOM1 with artificial zinc finger to unmethylated FWA promoter led to establishment of DNA methylation and FWA silencing. This process was blocked by mutations in components of the Pol V arm of the RdDM machinery, as well as by mutation of MORC6. We found that at some endogenous RdDM sites, MOM1 is required to maintain DNA methylation and a closed chromatin state. In addition, efficient silencing of newly introduced FWA transgenes was impaired by mutation of MOM1 or mutation of genes encoding the MOM1 interacting PIAL1/2 proteins. In addition to RdDM sites, we identified a group of MOM1 peaks at active chromatin near genes that colocalized with MORC6. These findings demonstrate a multifaceted role of MOM1 in genome regulation.

2023-06-10 | PXD039991 | Pride

DNA Topoisomerase 1α Promotes RNA-directed DNA Methylation and Histone Lysine 9 Dimethylation at Transposable Elements in Arabidopsis [Bisulfite-Seq]

Project description:RNA-directed DNA methylation (RdDM) is a transcriptional silencing mechanism mediated by small and long noncoding RNAs produced by the plant-specific RNA polymerases Pol IV and Pol V, respectively. Through a chemical genetics screen with a luciferase-based DNA methylation reporter, LUCL, we found that camptothecin, a compound with anti-cancer properties that targets DNA topoisomerase 1α (TOP1α) was able to de-repress LUCL by reducing its DNA methylation and H3K9 dimethylation (H3K9me2) levels. Further studies with Arabidopsis top1α mutants showed that TOP1α promotes RdDM by facilitating the production of Pol V-dependent long non-coding RNAs, AGONAUTE4 recruitment and H3K9me2 deposition at transposable elements (TEs).

2014-07-07 | GSE50691 | GEO

DNA Topoisomerase 1a Promotes RNA-directed DNA Methylation and Histone Lysine 9 Dimethylation at Transposable Elements in Arabidopsis [RNA-Seq]

2014-07-08 | GSE50719 | GEO

The effect of RNA polymerase V on 24-nt siRNA accumulation depends on DNA methylation contexts and histone modifications in rice

Project description:RNA-directed DNA methylation (RdDM) functions in de novo methylation in CG, CHG, and CHH contexts. Here, we performed map-based cloning of OsNRPE1, which encodes the largest subunit of Pol V, a key regulator of gene silencing and reproductive development in rice. We found that rice Pol V is required for CHH methylation on RdDM loci by transcribing long non-coding RNAs. Pol V influences the accumulation of 24-nt siRNAs in a locus-specific manner. Biosynthesis of 24-nt siRNAs on loci with high CHH methylation levels and low CG and CHG methylation levels tends to depend on Pol V. In contrast, low methylation levels in the CHH context and high methylation levels in CG and CHG contexts predisposes 24-nt siRNA accumulation to be independent of Pol V. H3K9me1 and H3K9me2 tend to be enriched on Pol V-independent 24-nt siRNA loci, whereas various active histone modifications are enriched on Pol V-dependent 24-nt siRNA loci. DNA methylation is required for 24-nt siRNAs biosynthesis on Pol V-dependent loci but not on Pol V-independent loci. Our results reveal the function of rice Pol V for long non-coding RNA production, DNA methylation, 24-nt siRNA accumulation, and reproductive development. This SuperSeries is composed of the SubSeries listed below.

2021-07-06 | GSE158711 | GEO

The effect of RNA polymerase V on 24-nt siRNA accumulation depends on DNA methylation contexts and histone modifications in rice [Bisulfite-Seq]

2021-07-07 | GSE158710 | GEO

The effect of RNA polymerase V on 24-nt siRNA accumulation depends on DNA methylation contexts and histone modifications in rice [ncRNA-Seq]

2021-07-07 | GSE158709 | GEO