- The C-terminal tail of UNC-60B (actin depolymerizing factor/cofilin) is critical for maintaining its stable association with F-actin and is implicated in the second actin-binding site. Ono, S., McGough, A., Pope, B.J., Tolbert, V.T., Bui, A., Pohl, J., Benian, G.M., Gernert, K.M., Weeds, A.G. J. Biol. Chem. (2001)