Profilin 2 is a ubiquitous actin monomer-binding protein belonging to the profilin family. It is thought to regulate actin polymerization in response to extracellular signals by binding to actin (1:1 ratio) and so affecting 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. Highly expressed in skeletal muscle, kidney and brain and less strongly in placenta, heart, liver and lung.