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). In association with OTU6/OTLD1, involved in transcriptional gene repression via histone deubiquitination and demethylation (PubMed:21690391). Interacts with CZS (PubMed:17224141). Interacts with OTU6/OTLD1 (PubMed:21690391). Expressed in the shoot and root apical regions of young seedlings. Expressed in cotyledons and inflorescences. Up-regulated expression of GLP2A/GLP5A due to derepression associated with hyperubiquitination of the target chromatin and H3K4 hypermethylation. Belongs to the flavin monoamine oxidase family. The predicted gene has been split into 3 genes: At1g62810, At1g62820 and At1g62830. Truncated N-terminus.