Phase separation of biomembrane-polyelectrolyte interaction system

This study models the regulatory process of biomacromolecular phase separation facilitated by biological membranes. Utilizing molecular dynamics simulations based on the coarse graining (CG) Martini force field, we investigate the phase separation of components within polyelectrolyte (PE) and cholesterol-containing dipalmitoyl phosphatidyl choline (DPPC) lipid membrane CDM. Combined with mean field theory, we reveal the intricate physical nature of component phase separation in the PE-CDM system. Our molecular dynamics simulations provide profound insights into the multiphase separation characteristics of the PE-CDM system and identify the driving factors behind phase separation. Furthermore, we delve deeper into the simulation results through mean field theory, elucidating the entropy effects during phase separation in the PE-CDM system and the regulatory mechanisms of component interactions. Our findings illustrate that biomembranes can indeed regulate the phase separation of biomacromolecules at their surfaces, with components such as cholesterol and DPPC playing crucial regulatory roles. Additionally, biomacromolecules can induce phase separation of biomembrane components. The results presented in this paper align with experimental observations, offering a deeper understanding of the critical mechanism by which biomembranes regulate intracellular biomacromolecule phase separation through prewetting. This study can provide valuable references for further research and potential applications.