Chromatin regulates expression of small RNAs to help maintain transposon methylome homeostasis in Arabidopsis
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA641096 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR12067230.fastq.gz | Fastqsanger.gz | |||
| SRR12067231.fastq.gz | Fastqsanger.gz | |||
| SRR12067232.fastq.gz | Fastqsanger.gz | |||
| SRR12067233.fastq.gz | Fastqsanger.gz | |||
| SRR12067234.fastq.gz | Fastqsanger.gz |
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Project description:We demonstrated that thousands of transposable elements (TEs) produce exceptionally high levels of siRNAs in Arabidopsis thaliana embryos.Depending on whether they are located in euchromatic or heterochromatic regions of the genome, bipartite-classified TEs generate siRNAs throughout embryogenesis according to two distinct patterns. siRNAs are transcribed in embryos and required to direct the re-establishment of DNA methylation on TEs from which they are derived in the new generation.
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Project description:TnpB nucleases represent the evolutionary precursors to CRISPR-Cas12 and are widespread in all domains of life. IS605-family TnpB homologs function in bacteria as programmable RNA-guided homing endonucleases driving transposon maintenance through DSB-stimulated homologous recombination. Here we uncover molecular mechanisms of transposition lifecycle of IS607-family elements that, remarkably, also encode group I introns. We discover molecular features for a candidate ‘IStron’ from Clostridium botulinum that allow the element to carefully control the relative levels of spliced products versus functional guide RNAs. Our results suggest that IStron transcripts have evolved a sensitive equilibrium to balance competing and mutually exclusive activities that promote transposon maintenance while limiting adverse fitness costs on the host. Collectively, this work highlights molecular innovation in the multi-functional utility of transposon-encoded noncoding RNAs.
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