Binds to actin and affects the structure of the cytoskeleton. At high concentrations, profilin prevents the polymerization of actin, whereas it enhances it at low concentrations. By binding to PIP2, it inhibits the formation of IP3 and DG. Has a high affinity for poly-proline. Occurs in many kinds of cells as a complex with monomeric actin in a 1:1 ratio. Expressed predominantly in endosperm but is also found at low levels in all tissues examined, including mature and germinated pollen. Phosphorylated by MAP kinases. Several isoforms of the allergen exist due to polymorphism. Causes an allergic reaction in human. Belongs to the profilin family.