Evidence for the Formation of Symmetric and Asymmetric DLPC-DAPC Lipid Bilayer Domains

Cellular Physiology and Biochemistry

关键词: DLPC;    DAPC;    Lipid bilayer;    Lipid domain;    Lipid raft;    Atomic force microscopy;   

DOI  :  10.1159/000350122

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Background/Aims We investigated if mixtures of the phosphatidylcholine (PC) lipids 1,2-dilauroyl-sn-glycero-3-phosphocholine (C120 PC; DLPC) and 1,2-diarachidoyl-sn-glycero-3-phosphocholine (C200 PC; DAPC), which differ by eight methylene groups in acyl chain length, lead to the spontaneous formation of distinct lipid rafts and asymmetric bilayers. Methods The experiments were performed using Atomic Force Microscopy (AFM). Results We show that DLPC and DAPC mixed at a molar ratio of 11 lead to the formation of single, double and triple bilayers with peaks at 6.14 ± 0.11, 13.27 ± 0.17 and 20.54 ± 0.46 nm, respectively (n=750). Within these formations discrete height steps of 0.92 nm can be resolved (n=422). Conclusion The most frequently observed height steps value of 0.92 nm matches best with the calculated mean lipid hydrophobic thickness difference for asymmetric C120 PC and C200 PC lipid bilayers of 0.88 nm. This indicates the ability of DLPC and DAPC to form asymmetric lipid bilayers.

【 授权许可】

CC BY-NC-ND