scholarly journals Preventing transcriptional gene silencing by active DNA demethylation

FEBS Letters ◽  
2005 ◽  
Vol 579 (26) ◽  
pp. 5889-5898 ◽  
Author(s):  
Avnish Kapoor ◽  
Fernanda Agius ◽  
Jian-Kang Zhu
Keyword(s):  
Gene Silencing ◽  
Dna Demethylation ◽  
Transcriptional Gene Silencing ◽  
Active Dna Demethylation

scholarly journals The Methyl-CpG-Binding Protein MBD7 Facilitates Active DNA Demethylation to Limit DNA Hyper-Methylation and Transcriptional Gene Silencing

2015 ◽  
Vol 57 (6) ◽  
pp. 971-983 ◽  
Author(s):  
Zhaobo Lang ◽  
Mingguang Lei ◽  
Xingang Wang ◽  
Kai Tang ◽  
Daisuke Miki ◽  
...  
Keyword(s):  
Gene Silencing ◽  
Binding Protein ◽  
Dna Demethylation ◽  
Transcriptional Gene Silencing ◽  
Active Dna Demethylation

scholarly journals A H3K9me2-Binding Protein AGDP3 Limits DNA Methylation and Transcriptional Gene Silencing in Arabidopsis

2021 ◽  
Author(s):  
Xuelin Zhou ◽  
Mengwei Wei ◽  
Wenfeng Nie ◽  
Yue Xi ◽  
Xuan Du ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Gene Silencing ◽  
Histone Acetylation ◽  
Binding Capacity ◽  
Dna Demethylation ◽  
Transcriptional Gene Silencing ◽  
Dna Hypermethylation ◽  
Active Dna Demethylation ◽  
Aromatic Cage ◽  
Deleterious Gene

AbstractDNA methylation is critical for tuning gene expression to prevent potentially deleterious gene-silencing. The Arabidopsis DNA glycosylase/lyase REPRESSOR OF SILENCING 1 (ROS1) initiates active DNA demethylation and is required for the prevention of DNA hypermethylation at thousands of genomic loci. However, the mechanism recruiting ROS1 to specific loci is not well understood. Here, we report the discovery of Arabidopsis AGENET Domain Containing Protein 3 (AGDP3) as a cellular factor required for ROS1-mediated DNA demethylation, and targets ROS1 to specific loci. We found that AGDP3 could bind to the H3K9me2 mark by its AGD12 cassette. The crystal structure of the AGDP3 AGD12 in complex with an H3K9me2 peptide reveals the molecular basis for the specific recognition, that the dimethylated H3K9 and unmodified H3K4 are specifically anchored into two different surface pockets. Interestingly, a histidine residue located in the methylysine binding aromatic cage enables AGDP3 pH-dependent H3K9me2 binding capacity. Considering the intracellular pH correlates with the histone acetylation status, our results provide the molecular mechanism for the regulation of ROS1 DNA demethylase by the gene silencing H3K9me2 mark and the potential crosstalk with active histone acetylation mark.

scholarly journals Insights into the Role of Transcriptional Gene Silencing in Response to Herbicide-Treatments in Arabidopsis thaliana

2021 ◽  
Vol 22 (7) ◽  
pp. 3314
Author(s):  
Catarine Markus ◽  
Ales Pecinka ◽  
Aldo Merotto
Keyword(s):  
Arabidopsis Thaliana ◽  
Gene Silencing ◽  
Dna Demethylation ◽  
Flavonoid Biosynthesis ◽  
Transcriptional Gene Silencing ◽  
Chemical Stimulus ◽  
Wild Type ◽  
Herbicide Treatment ◽  
Silencing Pathways ◽  
Increased Susceptibility

Herbicide resistance is broadly recognized as the adaptive evolution of weed populations to the intense selection pressure imposed by the herbicide applications. Here, we tested whether transcriptional gene silencing (TGS) and RNA-directed DNA Methylation (RdDM) pathways modulate resistance to commonly applied herbicides. Using Arabidopsis thaliana wild-type plants exposed to sublethal doses of glyphosate, imazethapyr, and 2,4-D, we found a partial loss of TGS and increased susceptibility to herbicides in six out of 11 tested TGS/RdDM mutants. Mutation in REPRESSOR OF SILENCING 1 (ROS1), that plays an important role in DNA demethylation, leading to strongly increased susceptibility to all applied herbicides, and imazethapyr in particular. Transcriptomic analysis of the imazethapyr-treated wild type and ros1 plants revealed a relation of the herbicide upregulated genes to chemical stimulus, secondary metabolism, stress condition, flavonoid biosynthesis, and epigenetic processes. Hypersensitivity to imazethapyr of the flavonoid biosynthesis component TRANSPARENT TESTA 4 (TT4) mutant plants strongly suggests that ROS1-dependent accumulation of flavonoids is an important mechanism for herbicide stress response in A. thaliana. In summary, our study shows that herbicide treatment affects transcriptional gene silencing pathways and that misregulation of these pathways makes Arabidopsis plants more sensitive to herbicide treatment.

scholarly journals Viroids as a Tool to Study RNA-Directed DNA Methylation in Plants

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1187
Author(s):  
Michael Wassenegger ◽  
Athanasios Dalakouras
Keyword(s):  
Dna Methylation ◽  
Rna Interference ◽  
Gene Silencing ◽  
Plant Cells ◽  
Transcriptional Gene Silencing ◽  
Rnai Machinery ◽  
Double Stranded Rna ◽  
Post Transcriptional Gene Silencing ◽  
Cumulative Amount

Viroids are plant pathogenic, circular, non-coding, single-stranded RNAs (ssRNAs). Members of the Pospiviroidae family replicate in the nucleus of plant cells through double-stranded RNA (dsRNA) intermediates, thus triggering the host’s RNA interference (RNAi) machinery. In plants, the two RNAi pillars are Post-Transcriptional Gene Silencing (PTGS) and RNA-directed DNA Methylation (RdDM), and the latter has the potential to trigger Transcriptional Gene Silencing (TGS). Over the last three decades, the employment of viroid-based systems has immensely contributed to our understanding of both of these RNAi facets. In this review, we highlight the role of Pospiviroidae in the discovery of RdDM, expound the gradual elucidation through the years of the diverse array of RdDM’s mechanistic details and propose a revised RdDM model based on the cumulative amount of evidence from viroid and non-viroid systems.

Sign in / Sign up

Export Citation Format

Share Document