Department of Physics & Astronomy and Department of Biological Sciences, University of Southern California, Los Angeles, California 90089, USA.
Phys Rev E. 2020 Dec;102(6-1):060401. doi: 10.1103/PhysRevE.102.060401.
Cell membranes show an intricate organization of lipids and membrane proteins into domains with distinct composition and hydrophobic thickness. Using mechanosensitive ion channels as a model system, we employ the membrane elasticity theory of lipid-protein interactions together with the Landau-Ginzburg theory of lipid domain formation to quantify protein-induced lipid bilayer thickness deformations in lipid bilayers with heterogeneous hydrophobic thickness. We show that protein-induced lipid bilayer thickness deformations yield, without any assumptions about preferential interactions between particular lipid and protein species, organization of lipids and membrane proteins according to their preferred hydrophobic thickness, and couple the conformational states of membrane proteins to the local membrane composition. Our calculations suggest that protein-induced lipid bilayer thickness deformations endow proteins in cell membranes with diverse and controlled mechanical environments that, in turn, allow targeted regulation of membrane proteins.
细胞膜显示出脂质和膜蛋白复杂的组织形式，形成具有不同组成和疏水性厚度的域。我们以机械敏感离子通道作为模型系统，利用脂质-蛋白质相互作用的膜弹性理论和脂质域形成的朗道-金兹堡理论，来量化具有不均匀疏水性厚度的脂质双层中蛋白质诱导的脂质双层厚度变形。我们表明，蛋白质诱导的脂质双层厚度变形导致脂质和膜蛋白根据其疏水性厚度的偏好进行组织，而无需对特定脂质和蛋白质种类之间的优先相互作用做出任何假设，并将膜蛋白的构象状态与局部膜组成耦合。我们的计算表明，蛋白质诱导的脂质双层厚度变形赋予细胞膜中的蛋白质多种可控的机械环境，从而可以有针对性地调节膜蛋白。
