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 under long day (LD) conditions. Acts upstream of MADS14 and MADS15. May also participate in the promotion of flowering under short day (SD) conditions. Interacts with FTIP1. Expressed in leaf vascular tissues (PubMed:18223202). Specifically expressed in the phloem including companion cells (PubMed:28254780). 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.