Lassing I, Lindberg U
Nature. 1985;314(6010):472-4. doi: 10.1038/314472a0.
There is evidence that the polymerization of actin takes place at the plasma membrane, and that profilactin (profilin/actin complex), the unpolymerized form of actin found in extracts of many non-muscle cells, serves as the immediate precursor. Both isolated profilin and profilactin interact with detergent when analysed by charge shift electrophoresis, indicating that they have amphipathic properties and may be able to interact directly with the plasma membrane. We demonstrate here that isolated profilin, as well as the profilactin complex, interacts with anionic phospholipids. Phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) was found to be the most active phospholipid, causing a rapid and efficient dissociation of profilactin with a concomitant polymerization of the actin in appropriate conditions. These and other observations suggest the possibility of a relationship between the induction of actin filament formation and the increased activity in the phosphatidylinositol cycle seen as a result of ligand-receptor interactions in various systems.
有证据表明肌动蛋白的聚合发生在质膜上，并且在许多非肌肉细胞提取物中发现的未聚合形式的肌动蛋白（肌动蛋白结合蛋白/肌动蛋白复合物）是直接前体。当通过电荷转移电泳分析时，分离出的肌动蛋白结合蛋白和肌动蛋白结合蛋白复合物都与去污剂相互作用，这表明它们具有两亲性，并且可能能够直接与质膜相互作用。我们在此证明，分离出的肌动蛋白结合蛋白以及肌动蛋白结合蛋白复合物与阴离子磷脂相互作用。发现磷脂酰肌醇4,5-二磷酸（PtdIns(4,5)P2）是最具活性的磷脂，在适当条件下可导致肌动蛋白结合蛋白快速有效解离，并伴随肌动蛋白聚合。这些以及其他观察结果表明，在各种系统中，由于配体-受体相互作用，肌动蛋白丝形成的诱导与磷脂酰肌醇循环中活性增加之间可能存在关联。
