Activation of Dynamin II by POPC in Giant Unilamellar Vesicles: A Two-Photon Fluorescence Microscopy Study.

Autor: Bagatolli, L., Binns, D., Jameson, D., Albanesi, J.
Zdroj: Journal of Protein Chemistry; Aug2002, Vol. 21 Issue 6, p383-391, 9p
Abstrakt: The interaction of dynamin II with giant unilamellar vesicles was studied using two-photon fluorescence microscopy. Dynamin II, labeled with fluorescein, was injected into a microscope chamber containing giant unilamellar vesicles, which were composed of either pure 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or a mixture of POPC and phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). Binding of the fluorescent dynamin II to giant unilamellar vesicles, in the presence and absence of PI(4,5)P2, was directly observed using two-photon fluorescence microscopy. This binding was also visualized using the fluorescent N-methylanthraniloyl guanosine 5′-[γ-thio]triphosphate analogue. The membrane probe 6-dodecanoyl-2-dimethylamine-naphthalene was used to monitor the physical state of the lipid in the giant unilamellar vesicles in the absence and presence of dynamin. A surprising finding was the fact that dynamin II bound to vesicles in the absence of PI(4,5)P2. Activation of the GTPase activity of dynamin II by pure POPC was then shown. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index