TY - JOUR
T1 - Flip-flop of phospholipids in vesicles
T2 - kinetic analysis with time-resolved small-angle neutron scattering
AU - Nakano, Minoru
AU - Fukuda, Masakazu
AU - Kudo, Takayuki
AU - Matsuzaki, Naoya
AU - Azuma, Takuto
AU - Sekine, Kazuhisa
AU - Endo, Hitoshi
AU - Handa, Tetsurou
PY - 2009/5/14
Y1 - 2009/5/14
N2 - We applied a time-resolved small-angle neutron scattering technique to vesicle systems to determine interparticle transfer and flip-flop of phospholipids. Measurements were performed for large unilamellar vesicles, consisting of dimyristoylphosphatidylcholine (DMPC), 1-palmitoyl-2- oleoylphosphatidylcholine (POPC), or 1-palmitoyl-2-oleoylphosphatidic acid (POPA), which differ either in their acyl chains or headgroup. POPC, which is analogous to naturally occurring phosphatidylcholines, exhibited no transbilayer transfer and very slow interbilayer migration. POPC on the inner leaflet of vesicles did not flop even when phospholipase D converted all POPC molecules on the outer leaflet into POPA, which was shown to exhibit fast flip-flop. From these results, together with the observation that the flip-flop of DMPC was entirely inhibited in the presence of cholesterol, it is deduced that the flip-flop of phosphatidylcholines does not take place spontaneously in cellular plasma membranes rich in cholesterol and that it requires enzymatic activities of energy-dependent and/or -independent flippases/floppases.
AB - We applied a time-resolved small-angle neutron scattering technique to vesicle systems to determine interparticle transfer and flip-flop of phospholipids. Measurements were performed for large unilamellar vesicles, consisting of dimyristoylphosphatidylcholine (DMPC), 1-palmitoyl-2- oleoylphosphatidylcholine (POPC), or 1-palmitoyl-2-oleoylphosphatidic acid (POPA), which differ either in their acyl chains or headgroup. POPC, which is analogous to naturally occurring phosphatidylcholines, exhibited no transbilayer transfer and very slow interbilayer migration. POPC on the inner leaflet of vesicles did not flop even when phospholipase D converted all POPC molecules on the outer leaflet into POPA, which was shown to exhibit fast flip-flop. From these results, together with the observation that the flip-flop of DMPC was entirely inhibited in the presence of cholesterol, it is deduced that the flip-flop of phosphatidylcholines does not take place spontaneously in cellular plasma membranes rich in cholesterol and that it requires enzymatic activities of energy-dependent and/or -independent flippases/floppases.
UR - http://www.scopus.com/inward/record.url?scp=67650082648&partnerID=8YFLogxK
U2 - 10.1021/jp900913w
DO - 10.1021/jp900913w
M3 - 学術論文
AN - SCOPUS:67650082648
SN - 1520-6106
VL - 113
SP - 6745
EP - 6748
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 19
ER -