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Full-length autonomous transposable elements are preferentially targeted by expression-dependent forms of RNA-directed DNA methylation

ABSTRACT: The diversity of small RNA-directed DNA methylation (RdDM) mechanisms have been underestimated due to the nearly complete transcriptional silencing of transposable elements (TEs) in the wild-type reference strains of Arabidopsis thaliana. In plants mutant for the SWI/SNF histone remodeler DDM1, TEs are globally activated due to loss of genome wide heterochromatin condensation. Transcriptionally activated TEs go through additional non-canonical forms of RdDM that are dependent on RNA Polymerase II expression. However, the global targets of the non-canonical RdDM pathway have not been explored. In an attempt to identify and contrast the targets of canonical and expression-dependent non-canonical RdDM, we performed MethylC-seq of genome-wide DNA methylation patterns from several RdDM mutants in either the TE-silent or the TE-active (ddm1) contexts. Arabidopsis wildtype and twenty RdDM pathway mutants

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Robert Schmitz

PROVIDER: E-GEOD-79746 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Comparing the targets of distinct RNA Directed DNA Methylation mechanisms in Arabidopsis thaliana

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