Real-time observation of lipoplex formation and interaction with anionic bilayer vesicles.
Real-time observation of lipoplex formation and interaction with anionic bilayer vesicles.
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实时观察脂质复合物的形成以及与阴离子双层囊泡的相互作用。
DOI：
10.1007/s00232-002-1050-4
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
MacDonald,RC
中科院分区：
文献类型：
--
作者：
Pantazatos,SP;MacDonald,RC
一个新的发展，允许直接观察单，成对的线性DNA与阳离子囊泡和DNA-阳离子脂质复合物与阴离子囊泡的相互作用。用一种新的阳离子磷脂衍生物1，2-二油酰-sn-甘油基-3-乙基磷酸胆碱制备了巨双层囊泡，并与DNA形成了阳离子脂质复合物。将阳离子囊泡与DNA接触，并且类似地，使复合物与由二油酰磷脂酰甘油（DOPG; 100%）、DOPG/二油酰磷脂酰乙醇胺（DOPE; 1：1）或DOPG/二油酰磷脂酰胆碱（DOPC; 1：1）组成的阴离子磷脂囊泡接触。视频荧光显微镜显示，与磷脂阴离子囊泡接触后，脂质复合物表现出四种不同类型的行为：粘附，囊泡破裂，膜穿孔（表现为囊泡收缩和/或内容物损失），和DNA的扩张（这总是伴随着膜穿孔）。在一种情况下，就在DNA扩增之前将脂质复合物注射到靶囊泡中。在所有其他情况下，DNA在囊泡的外表面上扩展，并且扩展得越快，它扩展的囊泡面积越大。考虑到细胞阴离子脂质掺入脂质复合物的可能性，DNA的扩增在细胞转染期间的DNA释放中可能是重要的。在与裸DNA接触时，巨大的阳离子囊泡通常破裂并将DNA浓缩成小颗粒。部分包被有DNA的阳离子囊泡的接触通常导致DNA包裹囊泡，导致囊泡破裂、囊泡融合（与其他附着的囊泡或脂质聚集体）或简单地停止运动。这些行为清楚地表明，DNA和囊泡可以部分或全部被另一个覆盖，从而改变表面电荷，其中包括允许DNA包被的囊泡与未包被的囊泡以及脂质包被的DNA与未包被的DNA的粘附。
A novel development has allowed for the direct observation of single, pairwise interactions of linear DNA with cationic vesicles and of DNA-cationic lipid complexes with anionic vesicles. A new cationic phospholipid derivative, l,2-dioleoyl-sn-glycero-3-ethylphosphocholine, was used to prepare giant bilayer vesicles and to form DNA-cationic lipid complexes (lipoplexes). The cationic vesicles were electrophoretically maneuvered into contact with DNA, and similarly, complexes were brought into contact with anionic phospholipid vesicles composed of dioleoylphosphatidylglycerol (DOPG; 100%), DOPG/dioleoylphosphatidylethanolamine (DOPE; 1:1) or DOPG/dioleoylphosphatidylcholine (DOPC; 1:1). Video fluorescence microscopy revealed that upon contact with phospholipid anionic vesicles, lipoplexes exhibited four different types of behavior: adhesion, vesicle rupture, membrane perforation (manifested as vesicle shrinkage and/or content loss), and expansion of DNA (which was always concomitant with membrane perforation.) In one instance, the lipoplex was injected into the target vesicle just prior to DNA expansion. In all other instances, the DNA expanded over the outer surface of the vesicle, and expansion was faster, the larger the area of vesicle over which it expanded. Given the likelihood of incorporation of cellular anionic lipids into lipoplexes, the expansion of the DNA could be important in DNA release during cell transfection. Upon contact with naked DNA, giant cationic vesicles usually ruptured and condensed the DNA into a small particle. Contact of cationic vesicles that were partially coated with DNA usually caused the DNA to wrap around the vesicle, leading to vesicle rupture, vesicle fusion (with other attached vesicles or lipid aggregates), or simply cessation of movement. These behaviors clearly indicated that both DNA and vesicles could be partly or fully covered by the other, thus modifying surface charges, which, among others, allowed adhesion of DNA-coated vesicles with uncoated vesicles and of lipid-coated DNA with uncoated DNA.