Combining Fluorescence Lifetime and Polarization Microscopy to Discriminate Phase Separated Domains in Giant Unilamellar Vesicles.

Fiche publication


Date publication

décembre 2008

Auteurs

Membres identifiés du Cancéropôle Est :
Pr MELY Yves


Tous les auteurs :
Haluska CK, Schroder AP, Didier P, Heissler D, Duportail G, Mely Y, Marques CM

Résumé

Using fluorescence lifetime microscopy we study the structure of lipid domains in giant unilamellar vesicles made from sphingomyelin, 1,2-dioleoyl-sn-glycero-3-phosphocholine, and cholesterol. Lifetimes and orientation of a derivative of the fluorescent probe DPH embedded in the membrane were measured for binary and ternary lipid mixtures incorporating up to 42 mol % of cholesterol. The results show that adding cholesterol always increases the lifetime of the probe studied. In addition, the analysis of the probe orientation indicates that cholesterol has little influence on the ordering of the sphingomyelin alkyl chains whereas it has a noticeable effect on the structure of the 1,2-dioleoyl-sn-glycero-3-phosphocholine chains. The measurements made on the orientation and lifetime of the probe show the structure of the membrane in its liquid ordered and liquid disordered domains.

Référence

Biophys J. 2008 Dec 15;95(12):5737-47