Dissipative Particle Dynamics Studies On Transport Mechanisms For Signal Transduction And Cell Penetrating Peptides Across Cellular Membrane

Cellular membrane, as an important part of cell, consists of lipid lipid molecules and glycoproteins. Cellular membrane plays important roles in stabling the environment inside and outside the membrane and controlling or selecting information and material passing in and out. On the aspect of signal transduction, in this work we used dissipative particle dynamics (DPD) simulation method to study the interplay between the clustering of transmembrane proteins and the coupling of anchored proteins. Then we investigated the penetration mechanism for cell-penetrating peptides (CPP) across the membrane with DPD simulations.The main conclusions are summarized as follows.1. N-varied dissipative particle dynamics (N-varied DPD) was used to study the interplay between the clustering of transmembrane proteins and the coupling of anchored proteins. The research is divided into tow parts. One is the study of the interplay between transmembrane proteins and andhored proteins on one side, and the other is the study of the iinterplay between transmembrane proteins and anchored proteins on both side of membrane. According to our study, the coupling and aggregation of anchored proteins on one side are observed, depending on the length of transmembrane proteins and that of anchored proteins. When anchored proteins are inserted into two sides of the membrane, the clustering of anchored proteins are influenced by transmembrane proteins, again depending on the hydrophobic length of transmembrane proteins. 2. We also investigated the penetration mechanism for cell-penetrating peptides (CPP) across the membrane with DPD simulation. In this part, we studied how the CPP size, the lengths for CPP hydrophoci and hydrophilic regions, the interaction between CPP and lipid, affect the penetration process.