Transcription activator that mediates floral transition in response to vernalization. Promotes inflorescence fate in apical meristems. Acts in a dosage-dependent manner. Probably involved in the transduction of RLK-mediated signaling (e.g. IMK3 pathway). Together with AP1 and SVP, controls the identity of the floral meristem and regulates expression of class B, C and E genes. When associated with SOC1, mediates effect of gibberellins on flowering under short-day conditions, and regulates the expression of LEAFY (LFY), which links floral induction and floral development. Confers inflorescence characteristics to floral primordia and early flowering. Interacts with IMK3/MRLK. Forms a homodimer and heterodimer with SOC1, AP1 and SVP through MADS-box domain. Interacts with the SEU-LUG corepressor complex when complexed to AP1. Interacts with AGL15 and AGL16. Translocation from the cytoplasm to the nucleus in the presence of IMK3. Mostly expressed in shoot apical meristems, including floral meristems. Also detected in stems, seedlings, leaves, flowers and siliques, and, to a lower extent, in roots. During vegetative phase, expressed in the entire shoot apical meristem and in emerging leaf primordia. During floral transition, gradually detectable in the transitional shoot apex and young cauline leaves. Detected in the inflorescence meristem. Present throughout the tunica (superficial layers) of the floral meristem during early stages of flower development. Later disappears prior to emergence of sepal primordia. At later stages of floral development, weakly expressed in the distal parts of stamens and carpels. Then restricted to pollen and the adaxial surface of the gynoecium. Induced by vernalization in a FLC-independent manner. Repressed by the floral homeotic genes AP1, LFY and SEP3 in emerging floral meristems to establish a floral identity and prevent inflorescence fate. Up-regulated at the shoot apex by SOC1. Phosphorylated by IMK3. Induced by vernalization. Delayed flowering.