Description
We demonstrate that REF6/JMJ12 (RELATIVE OF EARLY FLOWERING 6/Jumonji domain-containing protein 12) is an H3K27me3 and H3K27me2 demethylase. Plants overexpressing REF6/JMJ12 resemble mutants defective in H3K27me3-mediated gene silencing. Genetic interaction tests indicate that REF6/JMJ12 acts downstream of H3K27me3 methyltransferases. Moreover, loss of REF6/JMJ12 leads to ectopic and increased H3K27me3 and decreased mRNA expression of a large spectrum of genes involved in development and hormone responses to stimuli.