Mediator12 and 13 act as conditional anti-silencing factors in Arabidopsis [RNA-seq]

Mediator is a multi-protein complex which facilitates the initial steps of gene transcription. Mediator 12 (MED12) and MED13 are components of a module that reversibly associates with the core Mediator complex, and both positively and negatively regulates gene expression. Here, in an Arabidopsis mutant screen for factors that can bypass repressive epigenetic marks, we identified MED12 and MED13 as anti-silencing factors. Both are preferentially required for the expression of genes in the absence of H3K4me3, an activating chromatin mark. Thus, MED12 and MED13 respond to specific epigenetic states and can act as conditional positive gene regulators in Arabidopsis. In each experiments, a minimum of three replicates were analyzed. cct-2 and gct-2 mutants were compared to columbia-0. GFP-morc1/med12 and GFP-morc1/med13 were compared to GFP-morc1. GFP-morc1 was compared to GFP-wt. GFP-ddc/med12 and GFP-ddc/med13 were compared to GFP-ddc. GFP-ddc was compared to GFP-wt. Please also see description section of each individual sample.