论文标题
各向异性曲率诱导蛋白在膜管上的结合
Binding of anisotropic curvature-inducing proteins onto membrane tubes
论文作者
论文摘要
bin/Amphiphysin/RVS超家族蛋白和其他曲率诱导蛋白具有各向异性形状和各向异性弯曲的生物膜。在这里，我们报告了各向异性蛋白如何结合膜管，并使用平均场理论（包括方向依赖于排除体积）进行定向排序。蛋白质根据膜管的半径表现出二阶或一阶列过渡，并增加蛋白质密度。最大蛋白质结合和定向顺序的管曲率不同，并且因蛋白质的密度和刚度而变化。随着沿着管轴的外力的增加，从低蛋白质密度的大管半径到具有高密度的小半径的一阶跃迁一次，随后，蛋白质取向倾斜到管轴方向。当各向同性弯曲能用于具有椭圆形形状的蛋白质时，力依赖性曲线变为对称，而第一阶转变发生两次。该理论定量地重现了短蛋白的无网膜模拟结果，而由于蛋白簇的形成，长蛋白的偏差是可见的。
Bin/Amphiphysin/Rvs superfamily proteins and other curvature-inducing proteins have anisotropic shapes and anisotropically bend biomembrane. Here, we report how the anisotropic proteins bind the membrane tube and are orientationally ordered using mean-field theory including an orientation-dependent excluded volume. The proteins exhibit a second-order or first-order nematic transition with increasing protein density depending on the radius of the membrane tube. The tube curvatures for the maximum protein binding and orientational order are different and varied by the protein density and rigidity. As the external force along the tube axis increases, a first-order transition from a large tube radius with low protein density to a small radius with high density occurs once, and subsequently, the protein orientation tilts to the tube-axis direction. When an isotropic bending energy is used for the proteins with an elliptic shape, the force-dependence curves become symmetric and the first-order transition occurs twice. This theory quantitatively reproduces the results of meshless membrane simulation for short proteins, whereas deviations are seen for long proteins owing to the formation of protein clusters.
