Neurochemical Research

, Volume 5, Issue 7, pp 745–755 | Cite as

Transmembrane orientation of lipophilin in phosphatidylcholine vesicles

  • D. D. Wood
  • J. M. Boggs
  • M. A. Moscarello
Original Articles

Abstract

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 was 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.

Keywords

Dextran Phosphatidylcholine Myelin Protein Disulfonic Acid Phosphatidylcholine Vesicle 

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Copyright information

© Plenum Publishing Corporation 1980

Authors and Affiliations

  • D. D. Wood
    • 1
  • J. M. Boggs
    • 1
  • M. A. Moscarello
    • 1
  1. 1.The Research InstituteHospital for Sick ChildrenTorontoCanada

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