Probable histone demethylase that reduces the levels of histone H3 'Lys-4' methylation in chromatin of the floral repressor FLOWERING LOCUS C (FLC) and the sporophytically silenced floral repressor FWA (PubMed:17921315). Seems to act in partial redundancy with FLOWERING LOCUS D (FLD) to repress FLC expression (PubMed:17921315). Required for cytosine methylation of FWA (PubMed:17921315). Controls primary seed dormancy by regulating DOG1 and abscisic acid signaling-related genes (PubMed:25852712). Expressed in the shoot and root apical regions of young seedlings. Expressed in inflorescences. Belongs to the flavin monoamine oxidase family.