Department of Medicine, University of Florida, Gainesville, FL 32610, USA.
Bioessays. 2009 Nov;31(11):1150-60. doi: 10.1002/bies.200900049.
Rapid polymerization and depolymerization of actin filaments in response to extracellular stimuli is required for normal cell motility and development. Profilin is one of the most important actin-binding proteins; it regulates actin polymerization and interacts with many cytoskeletal proteins that link actin to extracellular membrane. The molecular mechanism of profilin has been extensively considered and debated in the literature for over two decades. Here we discuss several accepted hypotheses regarding the mechanism of profilin function as well as new recently emerged possibilities. Thermal noise is routine in molecular world and unsurprisingly, nature has found a way to utilize it. An increasing amount of theoretical and experimental research suggests that fluctuation-based processes play important roles in many cell events. Here we show how a fluctuation-based process of exchange diffusion is involved in the regulation of actin polymerization.
细胞的正常运动和发育依赖于肌动蛋白纤维的快速聚合和解聚来响应细胞外刺激。原肌球蛋白是最重要的肌动蛋白结合蛋白之一，它调节肌动蛋白聚合并与许多将肌动蛋白与细胞外膜连接的细胞骨架蛋白相互作用。二十多年来，文献中广泛讨论并争论了原肌球蛋白的分子机制。在这里，我们讨论了几个关于原肌球蛋白功能机制的公认假说，以及最近出现的新可能性。热噪声在分子世界中很常见，毫不奇怪，大自然已经找到了利用它的方法。越来越多的理论和实验研究表明，基于波动的过程在许多细胞事件中起着重要作用。在这里，我们展示了基于波动的交换扩散过程如何参与肌动蛋白聚合的调节。
