title: Lysophosphatidylcholine metabolism to 1,2-diacylglycerol in lymphoblasts: involvement of a phosphatidylcholine-hydrolyzing phospholipase C.
abstract: We have previously described the chemoattraction of lymphoblasts by lysophosphatidylcholine [Hoffman, R. D., et al. (1982) Proc. Natl. Acad. Sci. U.S.A. 79, 3285-3289]. In studying the mechanism of chemoattraction it was found that lysophosphatidylcholine was metabolized to 1,2-diacylglycerol by the lymphoblastic cell line 6C3HED. One route of metabolism involves the acylation of lysophosphatidylcholine to phosphatidylcholine with subsequent hydrolysis to 1,2-diacylglycerol and phosphocholine by the action of phospholipase C. The increase in cellular 1,2-diacylglycerol was established by metabolic experiments using [14C]glycerol-labeled lysophosphatidylcholine and by mass measurements of 1,2-diacylglycerol. The presence of a phosphatidylcholine-hydrolyzing phospholipase C was confirmed in 6C3HED cell homogenates. In intact cells, lysophosphatidylcholine induced a pattern of protein phosphorylation similar to those of 1,2-dioctanoylglycerol and phorbol 12-myristate 13-acetate, two known activators of protein kinase C. This pathway of lysophosphatidylcholine metabolism, which involves a phosphatidylcholine-hydrolyzing phospholipase C, may be important in the activation of protein kinase C independent of inositol phospholipid hydrolysis.
authors.affiliation: Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: J
authors.initials: J
authors.lastname: Nishijima
authors.forename: T M
authors.initials: TM
authors.lastname: Wright
authors.forename: R D
authors.initials: RD
authors.lastname: Hoffman
authors.forename: F
authors.initials: F
authors.lastname: Liao
authors.forename: D E
authors.initials: DE
authors.lastname: Symer
authors.forename: H S
authors.initials: HS
authors.lastname: Shin
mesh_terms: D000818:Animals; D002460:Cell Line; D004075:Diglycerides / Q000378:metabolism*; D005989:Glycerides / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D008223:Lymphoma / Q000201:enzymology; D008244:Lysophosphatidylcholines / Q000378:metabolism*; D051379:Mice; D010713:Phosphatidylcholines / Q000378:metabolism*; D010750:Phosphoproteins / Q000096:biosynthesis / Q000302:isolation & purification; D010766:Phosphorylation; D013953:Thymus Neoplasms / Q000201:enzymology; D010738:Type C Phospholipases / Q000378:metabolism*
chemical_list: D004075:Diglycerides; D005989:Glycerides; D008244:Lysophosphatidylcholines; D010713:Phosphatidylcholines; D010750:Phosphoproteins; D010738:Type C Phospholipases