Dependence of protein-induced lipid bilayer deformations on protein shape
Dependence of protein-induced lipid bilayer deformations on protein shape
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DOI：
10.1103/physreve.107.024403
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发表时间：
2023-02-06
影响因子：
2.4
通讯作者：
Haselwandter，Christoph A.
中科院分区：
文献类型：
--
作者：
Alas，Carlos D.;Haselwandter，Christoph A.
膜蛋白通常使周围的脂质双层膜变形，这在膜蛋白的功能、调节和组织中发挥重要作用。膜弹性理论对蛋白质引起的脂质双层变形提供了完美的描述，其中所有物理参数都可以直接从实验中确定。虽然对于具有近似圆形横截面的蛋白质最容易开发蛋白质引起的弹性双层变形的解析解，但结构生物学表明膜蛋白具有各种不同的形状，通常与圆形横截面有相当大的偏差。我们在这里开发了一种边界值方法（BVM），它允许针对与圆形横截面有任意大偏差的蛋白质形状，针对沿双层-蛋白质界面的恒定和可变边界条件，构建蛋白质诱导的弹性双层变形的解析解。我们将此 BVM 应用于蛋白质诱导的脂质双层厚度变形。我们的 BVM 再现了具有圆形横截面的蛋白质的可用分析解决方案，并且对于具有非圆形横截面的蛋白质，其产量与数值有限元解决方案非常一致。在此基础上，我们制定了与一般蛋白质形状相关的双层厚度变形能的简单解析近似，并表明，对于旋转对称性的适度偏差，该解析近似与 BVM 解非常一致。使用 BVM，我们调查了蛋白质诱导的弹性双层厚度变形对蛋白质形状的依赖性，从而探讨了蛋白质形状和双层厚度变形的耦合如何影响蛋白质寡聚化和蛋白质构象状态的转变。
Membrane proteins typically deform the surrounding lipid bilayer membrane, which can play an important role in the function, regulation, and organization of membrane proteins. Membrane elasticity theory provides a beautiful description of protein-induced lipid bilayer deformations, in which all physical parameters can be directly determined from experiments. While analytic solutions of protein-induced elastic bilayer deformations are most easily developed for proteins with approximately circular cross sections, structural biology has shown that membrane proteins come in a variety of distinct shapes, with often considerable deviations from a circular cross section. We develop here a boundary value method (BVM) that permits the construction of analytic solutions of protein-induced elastic bilayer deformations for protein shapes with arbitrarily large deviations from a circular cross section, for constant as well as variable boundary conditions along the bilayer-protein interface. We apply this BVM to protein-induced lipid bilayer thickness deformations. Our BVM reproduces available analytic solutions for proteins with circular cross section and yields, for proteins with noncircular cross section, excellent agreement with numerical, finite element solutions. On this basis, we formulate a simple analytic approximation of the bilayer thickness deformation energy associated with general protein shapes and show that, for modest deviations from rotational symmetry, this analytic approximation is in good agreement with BVM solutions. Using the BVM, we survey the dependence of protein-induced elastic bilayer thickness deformations on protein shape, and thus explore how the coupling of protein shape and bilayer thickness deformations affects protein oligomerization and transitions in protein conformational state.