Zhao Yanxiang, Du Qiang
Department of Mathematics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Jul;84(1 Pt 1):011903. doi: 10.1103/PhysRevE.84.011903. Epub 2011 Jul 7.
Prefusion and postfusion states of the biological fusion process between lipid bilayer vesicle membranes are studied in this paper. Based on the Helfrich-type continuum theory, a diffuse interface model is developed which describes the phase changes on the deformable vesicles via a scalar phase field function, and incorporates the adhesion effect between the different phases of the vesicles through a nonlocal interaction potential. Various equilibrium configurations in the prefusion and postfusion states are examined. The effects of spontaneous curvatures, bending, and Gaussian rigidities on the fusion process are discussed. Instead of considering only the regions in close contact as in many previous studies, the present approach allows us to include the energetic contributions from all parts of the vesicles. By carrying out simulations based on the gradient flow of the associated energy functional, we are also able to elucidate the dynamic transitions between the prefusion and postfusion states.
本文研究了脂质双层囊泡膜之间生物融合过程的预融合和后融合状态。基于赫尔弗里希型连续介质理论，建立了一个扩散界面模型，该模型通过标量相场函数描述可变形囊泡上的相变，并通过非局部相互作用势纳入囊泡不同相之间的粘附效应。研究了预融合和后融合状态下的各种平衡构型。讨论了自发曲率、弯曲和高斯刚性对融合过程的影响。与许多先前研究不同，本方法不仅考虑紧密接触区域，还能包含囊泡所有部分的能量贡献。通过基于相关能量泛函的梯度流进行模拟，我们还能够阐明预融合和后融合状态之间的动态转变。
