Proteolipid protein from the peripheral nervous system also contains covalently bound fatty acids.
Proteolipid protein, the major protein component of central nervous system (CNS) myelin, is known to contain approximately 2% by weight of covalently bound fatty acids. Recently, this protein was also found, though at a lower concentration, in the peripheral nervous system (PNS). The present study was undertaken to determine whether PNS proteolipid protein, like its CNS counterpart, was fatty acylated. Myelin PLP and DM-20, the two proteins that constitute the proteolipid protein fraction, were isolated from bovine sciatic nerves by chromatography on a methylated Sephadex G-100 column. The identity of the isolated proteins was determined by (a) SDS-PAGE, (b) Western blot analysis, and (c) amino acid analysis, and fractions containing only PLP and DM-20 were subjected to acid-methanolysis. Gas-liquid chromatography of the released methyl esters revealed the presence of fatty acids (2.9% w/w) distributed as approximately 47% palmitic, 22% stearic, and 19% oleic acid. Similar results were obtained for bovine white matter proteolipid protein when isolated and analyzed in parallel with the peripheral nerve protein. These data unequivocally demonstrate that both PNS and CNS proteolipid protein are equally acylated.
Tetzloff
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Biochemistry Dept. University of New Mexico-School of Medicine, Albuquerque 87131.
Bizzozero
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OA
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001923:Brain Chemistry; D002417:Cattle; D002849:Chromatography, Gas; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005227:Fatty Acids / Q000032:analysis*; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000302:isolation & purification*; D019301:Oleic Acid; D009829:Oleic Acids / Q000032:analysis; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000032:analysis; D011510:Proteolipids / Q000737:chemistry / Q000302:isolation & purification*; D012584:Sciatic Nerve / Q000737:chemistry*; D013229:Stearic Acids / Q000032:analysis
D000596:Amino Acids; D005227:Fatty Acids; D009419:Nerve Tissue Proteins; D009829:Oleic Acids; D010169:Palmitic Acids; D011510:Proteolipids; D013229:Stearic Acids; D019301:Oleic Acid; D019308:Palmitic Acid; C031183:stearic acid