Fatty acids covalently bound to erythrocyte proteins undergo a differential turnover in vivo.
Recently, covalently bound fatty acids have been identified on a variety of proteins. Many of these acyl proteins are physiologically important, and the lipid modification often appears to be essential for their function. In this investigation mature erythrocytes have been used to study in detail the metabolic behavior of protein-bound fatty acids. Although deficient in protein synthesis, these cells are still able to covalently attach [3H]palmitic acid to proteins located at the plasma membrane and its associated cytoskeleton. Linkage analyses demonstrated that the labeled polypeptides contained ester- or thioester-bound fatty acids. The covalent binding of fatty acid was rapidly reversible. Half-lives of the protein-bound fatty acid molecules ranged from less than 30 min to more than 3 h. The deacylation reaction was not due to a chemically labile linkage of protein and fatty acid but appeared to be physiologically induced. Differences in the fatty acid turnover rates between the acyl proteins suggested an independent regulation of their lipid turnover. A number of proteins underwent dynamic fatty acid acylation, indicating that palmitylated proteins undergoing fatty acid turnover are not a rare exception.
Staufenbiel
M
M
Max-Planck-Institut für Zellbiologie, Abteilung Traub, Ladenburg/Heidelberg, Federal Republic of Germany.
D000818:Animals; D017487:Ankyrins; D001798:Blood Proteins / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D005227:Fatty Acids / Q000097:blood*; D006878:Hydroxides / Q000494:pharmacology; D019811:Hydroxylamine; D006898:Hydroxylamines / Q000494:pharmacology; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism; D000432:Methanol; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism; D010713:Phosphatidylcholines / Q000097:blood; D010714:Phosphatidylethanolamines / Q000097:blood; D011188:Potassium / Q000494:pharmacology; D017680:Potassium Compounds; D011817:Rabbits; D013109:Sphingomyelins / Q000097:blood; D014316:Tritium
D017487:Ankyrins; D001798:Blood Proteins; D005227:Fatty Acids; D006878:Hydroxides; D006898:Hydroxylamines; D008565:Membrane Proteins; D010169:Palmitic Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D017680:Potassium Compounds; D013109:Sphingomyelins; D014316:Tritium; D019811:Hydroxylamine; D019308:Palmitic Acid; D011188:Potassium; C029943:potassium hydroxide; D000432:Methanol