TY - JOUR
T1 - Effect of Ca2+ on vesicle fusion on solid surface
T2 - An in vitro model of protein-accelerated vesicle fusion
AU - Shinozaki, Youichi
AU - Sittonen, Ari M.
AU - Sumitomo, Koji
AU - Furukawa, Kazuaki
AU - Torimitsu, Keiichi
PY - 2008/7/18
Y1 - 2008/7/18
N2 - Lipid vesicle fusion is an important reaction in the cell. Calcium ions (Ca2+) participate in various important biological events including the fusion of vesicles with cell membranes in cells. We studied the effect of Ca2+ on the fusion of egg yolk phosphatidylcholine/brain phosphatidylserine (eggPC/brainPS) lipid vesicles on a mica substrate with fast scanning atomic force microscopy (AFM). When unattached and unfused lipid vesicles on mica were rinsed away, discrete patches of fused vesicles were observed under high Ca2+ concentrations. At 0 mM Ca2+, lipid vesicles were fused on mica and formed continuous supported lipid bilayers (SLBs) covering almost the entire mica surface. The effect of Ca2+ on SLB formation was offset by a Ca2+ chelating agent. When lipid vesicles were added during AFM observation, vesicles fused on mica and covered almost all areas even under high Ca2+ concentrations. These results indicate that force between AFM tip and vesicles overcomes the Ca 2+-reduced fusion of lipid vesicles.
AB - Lipid vesicle fusion is an important reaction in the cell. Calcium ions (Ca2+) participate in various important biological events including the fusion of vesicles with cell membranes in cells. We studied the effect of Ca2+ on the fusion of egg yolk phosphatidylcholine/brain phosphatidylserine (eggPC/brainPS) lipid vesicles on a mica substrate with fast scanning atomic force microscopy (AFM). When unattached and unfused lipid vesicles on mica were rinsed away, discrete patches of fused vesicles were observed under high Ca2+ concentrations. At 0 mM Ca2+, lipid vesicles were fused on mica and formed continuous supported lipid bilayers (SLBs) covering almost the entire mica surface. The effect of Ca2+ on SLB formation was offset by a Ca2+ chelating agent. When lipid vesicles were added during AFM observation, vesicles fused on mica and covered almost all areas even under high Ca2+ concentrations. These results indicate that force between AFM tip and vesicles overcomes the Ca 2+-reduced fusion of lipid vesicles.
KW - Calcium
KW - Fast scanning AFM
KW - Lipid
KW - Supported lipid bilayer
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U2 - 10.1143/JJAP.47.6164
DO - 10.1143/JJAP.47.6164
M3 - Article
AN - SCOPUS:55149090508
VL - 47
SP - 6164
EP - 6167
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 7 PART 3
ER -