The transbilayer movement of phosphatidylcholine in vesicles reconstituted with intrinsic proteins from the human erythrocyte membrane.
Vesicles have been prepared from 18 : 1c/18 : 1c-phosphatidylcholine with or without purified glycophorin or partially purified band 3 (obtained by organomercurial gel chromatography). The vesicles have been characterized by freeze-fracture electron microscopy, binding studies to DEAE-cellulose, 31P-NMR and K+ trap measurements. Pools of phosphatidylcholine available for exchange have been investigated using phosphatidylcholine exchange protein from bovine liver. The protein-containing vesicles both exhibit exchangeable pools larger than the fraction of phosphatidylcholine in the outer monolayer, whereas in the protein-free vesicles the exchangeable pool is consistent with the outer monolayer. The results indicate that both glycophorin and the partially purified band 3 preparation enhance the transbilayer movement of phosphatidylcholine.
D004591:Electrophoresis, Polyacrylamide Gel; D004910:Erythrocyte Membrane / Q000032:analysis*; D004912:Erythrocytes / Q000032:analysis*; D005614:Freeze Fracturing; D006801:Humans; D008051:Lipid Bilayers; D009682:Magnetic Resonance Spectroscopy; D008565:Membrane Proteins / Q000097:blood*; D008854:Microscopy, Electron; D010713:Phosphatidylcholines
D008051:Lipid Bilayers; D008565:Membrane Proteins; D010713:Phosphatidylcholines