Project description:We applied the tiling arrays to study the Arabidopsis whole-genome transcriptome in Arabidopsis axe1-5 and met1-3 mutants. Fifteen-day-old Arabidopsis plants grown on the agar plates were harvested. The total RNA was prepared from 15-day-old Arabidopsis plants (axe1-5 (hda6 mutant), DR5 (parental line of axe1-5), met1-3 and Col) and used for the microarray hybridization. Three replicative hybridization experiments for each strand array were carried out using the independent biological RNA samples.
Project description:DNA methylation in the promoters of plant genes sometimes leads to transcriptional repression, and the wholesale removal of DNA methylation as seen in methyltransferase mutants results in drastic changes in gene expression and severe developmental defects. However, many cases of naturally-occurring DNA methylation variations have been reported, whereby the altered expression of differentially methylated genes is responsible for agronomically important traits. The ability to manipulate plant methylomes to generate populations of epigenetically distinct individuals could provide invaluable resources for breeding and research purposes. Here we describe “epimutagenesis”, a novel method to rapidly generate variation of DNA methylation through random demethylation of the Arabidopsis thaliana genome. This method involves the expression of a human Ten-eleven translocation (TET) enzyme, and results in widespread hypomethylation that can be inherited to subsequent generations, mimicking mutants in the maintenance DNA methyltransferase met1. Application of TET-mediated epimutagenesis to agriculturally significant plants may result in differential expression of alleles normally silenced by DNA methylation, uncovering previously hidden phenotypic variations.
