巨型囊泡的侧向相分离与出芽LateralSeparationandBuddingof.PDF

2005 年第63 卷 化 学 学 报 Vol. 63, 2005 第14 期, 1375～1378 ACTA CHIMICA SINICA No. 14, 1375～1378 ·研究简报· 巨型囊泡的侧向相分离与出芽 李 莉 林美玉 邱 枫* 杨玉良* (复旦大学高分子科学系 聚合物分子工程教育部重点实验室 上海 200433) 摘要 用电形成法制备含三组分二油酰磷脂酰胆碱(DOPC)/二棕榈酰磷脂酰胆碱(DPPC)/胆固醇(Chol) 的巨型囊泡, 以 TR-DPPE 为荧光染色剂, 在荧光显微镜下直接观察膜的侧向相分离与微区相凸起出芽的耦合. 发现囊泡膜内的相分离 具有诱导期, 相分离速度很快, 形成的微相区在整个囊泡球面上均衡分布. 各微相区的出芽不是同时进行, 为逐个随 机发生. 每次出芽的时间小于0.5 s. 分相与出芽的耦合使球面上的不同微区之间不会相互融合成更大的微区. 关键词 巨型囊泡; 侧向相分离; 出芽 Lateral Separation and Budding of Giant Vesicles LI, Li LIN, Mei-Yu QIU, Feng* YANG, Yu-Liang* (Key Laboratory of Molecular Engineering of Polymers of Ministry of Education, Department of Macromolecular Science, Fudan University, Shanghai 200433) Abstract Lateral phase separation and budding of giant vesicles prepared by electroformation with a model mixture, 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/1,2-dipalmitoyl-sn-glycero-3-phospho- choline (DPPC)/Cholesterol (Chol), were observed directly by fluorescence microscopy. It was found that the separation after a short retardation time was a fast process and the domains thus formed were regularly distributed on the surface of the vesicles. Budding of the microdomains occurred one by one and the time to finish a budding process was less than 0.5 s. The coupling of the separation and budding stopped further fusing and growing of the microdomains. Keywords giant vesicle; lateral phase separation; budding [1] 一. Rothman 和Schekman 就因发现了配合膜泡出芽与融 脂双层膜 在生物体系中无处不在,