Mechanosensitive kinetic preference of actin-binding protein to actin filament
Mechanosensitive kinetic preference of actin-binding protein to actin filament
复制标题
肌动蛋白结合蛋白对肌动蛋白丝的机械敏感性动力学偏好
DOI：
10.1103/physreve.93.042403
复制
发表时间：
2016
影响因子：
2.4
通讯作者：
Yasuhiro Inoue and Taiji Adachi
中科院分区：
文献类型：
--
作者：
小杉賢一朗;正岡直也;糸数哲;藤本将光;中村公人;勝山正則;Yasuhiro Inoue and Taiji Adachi
肌动蛋白结合蛋白对肌动蛋白细丝的动力学偏好被外力改变。这种改变的运动偏好在很大程度上是重塑肌动蛋白细胞骨架结构以响应细胞内力的原因。在重塑过程中，肌动蛋白结合蛋白和肌动蛋白细丝在恒温条件下相互作用，因为细胞是内稳态的。在这样的温度平衡状态下，我们可以严格和热力学地将肌动蛋白结合蛋白的化学势与肌动蛋白细丝上的压力联系起来。根据这种关系，我们可以构建一个物理模型来解释肌动蛋白结合蛋白对肌动蛋白细丝的依赖于力的动力学偏好。为了验证该模型，我们分析了Arp2/3和cofilin对肌动蛋白细丝的动力学偏好的机械敏感性交替。我们表明，这个模型捕捉到了这些肌动蛋白结合蛋白对力的定性反应，正如实验观察到的那样。此外，我们的理论结果表明，根据结合区的结构参数，肌动蛋白结合蛋白即使在相同的机械信号张力下也可以表现出不同的动力学反应，其中肌动蛋白微丝的双螺旋性质在微丝的拉伸-扭转耦合中也起着关键作用。
The kinetic preference of actin-binding proteins to actin filaments is altered by external forces on the filament. Such an altered kinetic preference is largely responsible for remodeling the actin cytoskeletal structure in response to intracellular forces. During remodeling, actin-binding proteins and actin filaments interact under isothermal conditions, because the cells are homeostatic. In such a temperature homeostatic state, we can rigorously and thermodynamically link the chemical potential of actin-binding proteins to stresses on the actin filaments. From this relationship, we can construct a physical model that explains the force-dependent kinetic preference of actin-binding proteins to actin filaments. To confirm the model, we have analyzed the mechanosensitive alternation of the kinetic preference of Arp2/3 and cofilin to actin filaments. We show that this model captures the qualitative responses of these actin-binding proteins to the forces, as observed experimentally. Moreover, our theoretical results demonstrate that, depending on the structural parameters of the binding region, actin-binding proteins can show different kinetic responses even to the same mechanical signaltension, in which the double-helix nature of the actin filament also plays a critical role in a stretch-twist coupling of the filament.