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Updated: Aug 18, 2026

Determination of Lipid Raft Partitioning of Fluorescently-tagged Probes in Living Cells by Fluorescence Correlation Spectroscopy (FCS)
Published on: April 6, 2012
[Calcium-dependent association of membrane rafts]
E B Babiĭchuk1, V S Babiĭchuk, V M Danylova
1Petro Bogach Institute of Physiology, Taras Schevchenko Kyiv National University, Kyiv, Ukraine.
Abstract:
The plasma membrane of eucariotic cells is composed from spatially distinct regions enriched in sphingomyelin and cholesterol (so called membrane rafts), which are surrounded by glycerophospholipid milieu. The ability of these regions (membrane microdomains) to recruit specific enzymes and structural proteins results in spatial segregation of elements of different signaling systems. To the great extent, such segregation is a result of membrane raft association. Our results demonstrate that association of individual rafts is a controlled process, which is regulated, as many other biological processes, by Ca2+. Annexin II, a member of phospholipid-binding protein family, interacts with preparations of membrane rafts in a Ca(2+)-dependent manner thus resulting in reversible raft-association. Occurring in the presence of physiologically relevant calcium concentrations these interactions may play a role in regulation of smooth muscle contraction.
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