Cationic lipids and cationic ligands induce DNA helix denaturation: detection of single stranded regions by KMnO4 probing

FEBS Letters

Rao, N.Madhusudhana¹  Prasad, T.K¹  Gopal, Vijaya¹ 

[1] Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India

关键词: Cationic lipid;    DNA condensation;    DNA unwinding;    KMnO4 probing;    Transfection;    Cationic lipid:DNA complex;    CD;    circular dichroism;    CLDC;    cationic lipid:DNA complex;    CTAB;    cetyl trimethylammonium bromide;    DC-Chol;    3β-[N-(N′;    N′-dimethylaminoethane)-carbamoyl]cholesterol;    DDAB;    dimethyldioctadecylammonium bromide;    DMRIE-C;    1;    2-dimyristyloxypropyl-3-dimethyl-hydroxy ethyl ammonium bromide-cholesterol;    DOPC;    1;    2-dioleoyl-sn-glycero-3-phosphocholine;    DOPE;    L-α-dioleoyl phosphatidylethanolamine;    DOTAP;    1;    2-dioleoyl-3-trimethylammonium-propane;    DOTMA;    N-[1-(2;    3-dioleyloxy)propyl]-N;    N;    N-trimethylammonium chloride;    FTIR;    Fourier transform infrared;    N/P charge ratio;    positive charge of tertiary ammonium/negative charge of phosphate;   

DOI  :  10.1016/S0014-5793(03)00922-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Cationic lipids and cationic polymers are widely used in gene delivery. Using 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) as a cationic lipid, we have investigated the stability of the DNA in DOTAP:DNA complexes by probing with potassium permanganate (KMnO₄). Interestingly, thymidines followed by a purine showed higher susceptibility to cationic ligand-mediated melting. Similar studies performed with other water-soluble cationic ligands such as polylysine, protamine sulfate and polyethyleneimine also demonstrated melting of the DNA but with variations. Small cations such as spermine and spermidine and a cationic detergent, cetyl trimethylammonium bromide, also rendered the DNA susceptible to modification by KMnO₄. The data presented here provide direct proof for melting of DNA upon interaction with cationic lipids. Structural changes subsequent to binding of cationic lipids/ligands to DNA may lead to instability and formation of DNA bubbles in double-stranded DNA.

【 授权许可】

Unknown