Transmembrane orientation of lipophilin in phosphatidylcholine vesicles.
Lipophilin, a hydrophobic myelin protein, was incorporated into phosphatidylcholine vesicles by dialysis from 2-chloroethanol which has been shown to produce single-layered lipid-protein vesicles. These vesicles were labeled with a nonpenetrating surface-labeling reagent, 4,4'-diisothiocyano-2,2'-ditritiostilbene disulfonic acid, ([3H]DIDS), in order to determine if the protein completely spans the bilayer. After labeling the vesicles, lipophilin was isolated. At least 88% of the protein ws labeled with [3H]DIDS. Dextran (mol wt 250,000-275,000) was converted to the dialdehyde form and reacted with lipophilin-PC vesicles. In this case greater than 90% of the protein was complexed to the dextran. The high degree of labeling obtained with both compounds was consistent with a model in which lipophilin was considered to span the bilayer completely.
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D002850:Chromatography, Gel; D003911:Dextrans / Q000494:pharmacology; D006801:Humans; D008051:Lipid Bilayers; D008081:Liposomes; D009185:Myelin Proteins / Q000378:metabolism*; D010539:Permeability; D010713:Phosphatidylcholines; D011510:Proteolipids / Q000378:metabolism*; D013997:Time Factors; D014598:Uteroglobin
D003911:Dextrans; D008051:Lipid Bilayers; D008081:Liposomes; D009185:Myelin Proteins; D010713:Phosphatidylcholines; D011510:Proteolipids; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; C026948:dextran dialdehyde; D014598:Uteroglobin; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid