New structures in complex formation between DNA and cationic liposomes visualized by freeze—fracture electron microscopy

FEBS Letters

Sorgi, Frank L.²  Sternberg, Brigitte¹  Huang, Leaf² 

[1] Institute of Ultrastructure Research, Medical School, Friedrich-Schiller-University Jena, Ziegelmühlenweg 1, Jena D-07743, Germany;Departments of Pharmacology and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15261, USA

关键词: Cationic liposome;    Plasmid DNA;    Transfection;    Freeze—fracture electron microscopy;    DC-Chol;    3β[N-(N′;    N′-dimethylaminoet hane)-Carbamoyl]cholesterol;    DOPE;    1;    2-dioleoyl-sn-glycero-3-phosphoethanolamine;    DOTMA;    N-[1-[2;    3-dioleyloxy)propyl]-n;    n;    n-trimethylammonium chloride;   

DOI  :  10.1016/0014-5793(94)01315-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Structures formed during interaction of cationic liposomes and plasmid DNA were studied by freeze—fracture electron microscopy and their morphology was found to be dependent on incubation time and DNA concentration. These structures were formed with liposomes composed of DC-Chol and DOPE after 30 min incubation at DNA: lipid concentrations encompassing maximal transfection activity. They resembled liposome complexes (meatballs) and additionally bilayer-covered DNA tubules (spaghetti), whereby the DNA-tubules were found to be connected to the liposome complexes as well as occurring free in the suspension. At later times and higher DNA-to-liposome ratios the complexes grow larger while their membranes become discontinuous, allowing the self-encapsulation of the DNA. The relative transfection potency of the various morphologically distinct structures is discussed.

【 授权许可】

Unknown