Probable mobile flower-promoting signal (florigen) that moves from the leaf to the shoot apical meristem (SAM) and induces flowering. Promotes the transition from vegetative growth to flowering downstream of HD1 and EHD1 under short day (SD) conditions. Acts upstream of MADS14 and MADS15. Expressed in the inner region of the SAM, stem and leaf blade vascular tissues (at protein level). Expressed with a circadian rhythm showing a peak at dawn and then decreasing to reach the lowest levels early in the night in SD conditions. Belongs to the phosphatidylethanolamine-binding protein family.