Structural polymorphism and functional differentiation of actin filaments

该项目的目标是了解细胞内不同的肌动蛋白丝如何执行不同的功能。我们发现，螺旋间距较长的拉伸肌动蛋白丝对肌凝蛋白II具有较高的亲和力。我们还发现两种主要的肌动蛋白结合蛋白myosin II和cofilin以互斥的方式结合到肌动蛋白丝上，尽管这两种蛋白并不竞争肌动蛋白上的结合位点。这些结果支持了我们的假设，即不同原子结构的肌动蛋白丝对不同的肌动蛋白结合蛋白具有不同的亲和力，从而导致细胞内的功能分化。

The goal of this project is to understood how different actin filaments within a cell perform different functions. We found that stretched actin filaments with a longer helical pitch have higher affinity for myosin II. We also found that myosin II and cofilin, two major actin binding proteins, bound to actin filaments in a mutually exclusive manner, even though the two proteins do not compete for a binding site on actin. These results support our hypothesis that actin filaments of different atomic structures have different affinities for different actin binding proteins, leading to functional differentiation within cells.