Protein zero of peripheral nerve myelin: biosynthesis, membrane insertion, and evidence for homotypic interaction.
Protein zero (P0), an integral membrane glycoprotein synthesized by Schwann cells, is the major glycoprotein of peripheral nerve myelin. The predicted disposition of P0 with respect to the membrane bilayer postulates the existence of extracellular and intracellular domains, that mediate compaction of the myelin lamellae. We used in vitro translations programmed with sciatic nerve mRNA and cells transfected with a P0 cDNA construct to study the biosynthesis and topology of P0 in the bilayer. The behavior of P0 at the cell surface, when expressed under physiological conditions, was also examined. We have verified the topological predictions of an earlier model, derived from analysis of a P0 cDNA, and provide evidence that the extracellular domain of P0 mediates homotypically cell-cell interactions in the transfectants.
D'Urso
D
D
Department of Anatomy and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York 10032.
Brophy
P J
PJ
Staugaitis
S M
SM
Gillespie
C S
CS
Frey
A B
AB
Stempak
J G
JG
Colman
D R
DR
D000595:Amino Acid Sequence; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D004591:Electrophoresis, Polyacrylamide Gel; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells / Q000378:metabolism; D008051:Lipid Bilayers; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D008970:Molecular Weight; D018993:Myelin P0 Protein; D009185:Myelin Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D009186:Myelin Sheath / Q000378:metabolism*; D010455:Peptides / Q000138:chemical synthesis; D010957:Plasmids; D011061:Poly A / Q000235:genetics; D014176:Protein Biosynthesis; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger; D051381:Rats; D011919:Rats, Inbred Strains; D012584:Sciatic Nerve / Q000378:metabolism*; D014162:Transfection
D008051:Lipid Bilayers; D008562:Membrane Glycoproteins; D018993:Myelin P0 Protein; D009185:Myelin Proteins; D010455:Peptides; D012333:RNA, Messenger; D011061:Poly A; D012313:RNA