title: Direct identification of palmitic acid as the lipid attached to p21ras.
abstract: p21v-H-ras, the transforming protein of Harvey murine sarcoma virus, contains a covalently attached lipid. Using thin-layer chromatography, we identified the acyl group as the 16-carbon saturated fatty acid palmitic acid. No myristic acid was detected in fatty acids released from in vivo-labeled p21v-H-ras. The p21v-K-ras protein encoded by Kirsten sarcoma virus was also palmitylated. The processing and acylation of p21v-K-ras however differed from that of p21v-H-ras. Three forms of [3H]palmitic acid-labeled p21ras proteins were detected in Kirsten sarcoma virus-transformed cells. This contrasted with Harvey sarcoma virus, in which two forms of p21v-H-ras contained palmitic acid. Analysis by partial proteolysis of p21v-H-ras labeled with [3H]palmitic acid suggested that all of the lipid found in intact p21v-H-ras was located in the C-terminal region. On sodium dodecyl sulfate-polyacrylamide gels, p21v-H-ras labeled with [3H]palmitic acid migrated slightly ahead of the majority of p21v-H-ras. Of the mature forms of p21v-H-ras, apparently only a subpopulation contains palmitic acid.
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D003545:Cysteine / Q000378:metabolism; D006251:Harvey murine sarcoma virus / Q000235:genetics*; D051379:Mice; D019814:Myristic Acid; D009227:Myristic Acids / Q000032:analysis; D015689:Oncogene Protein p21(ras); D009856:Oncogene Proteins, Viral / Q000096:biosynthesis; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000032:analysis* / Q000378:metabolism; D009053:Sarcoma Viruses, Murine / Q000235:genetics*
chemical_list: D009227:Myristic Acids; D009856:Oncogene Proteins, Viral; D010169:Palmitic Acids; D019814:Myristic Acid; D019308:Palmitic Acid; D015689:Oncogene Protein p21(ras); D003545:Cysteine