Analysis of polyploidy-associated transcriptional gene silencing (paTGS) mutants

A case of transcriptional gene silencing, originally observed in tetraploid Arabidopsis plants, created an epiallele resistant to many mutations or inhibitor treatments that activate other suppressed genes. This raised the question about the molecular basis of this extreme stability. A combination of forward and reverse genetics, transcriptome profiling and drug application provides evidence for a double safeguard system that is only alleviated upon the simultaneous removal of both DNA methylation and histone methylation by loss of DDM1 or HOG1 acitivity. Three biological replicates per line are provided. C2S1 = Wt line; hog1-7=774; ddm1-12=1135