Effect of phosphatidyl-L-serine and vinculin on actin polymerization

The effects of phosphatidyl-L-serine (PS) and/or vinculin on actin polymerization are examined by spectrophotometry, viscometry and electrophoresis. Actin polymerization is inhibited by PS alone and stimulated by PS and vinculin. The results suggest that actin does not directly adhere to cell membrane and that vinculin is a protein which is involved in structures connecting actin microfilaments to cell membranes.