Selective modulation of membrane sphingomyelin fatty acid turnover by nigericin. A study in the rat reticulocyte.
Exposure of rat reticulocytes to Nigericin produced a selective modulation of fatty acid incorporation into sphingomyelin (SM) of the cell membrane, via changes in SM acylation kinetics. At physiological fatty acid concentration, Nigericin accelerated 8-fold SM acylation by decreasing the apparent K(m) for oleate from 14.7 microM to 2.0 microM. The response was diminished in high K(+)-containing media, suggesting an effect of Nigericin as K+ transporter. This constitutes a novel piece of evidence for the important role of ions in SM metabolism.
Le Petit-Thevenin
J
J
INSERM U.260, Faculté de Médecine, Marseille, France.
Nobili
O
O
Vérine
A
A
Boyer
J
J
D000215:Acylation; D000818:Animals; D017920:Antiporters / Q000378:metabolism; D004910:Erythrocyte Membrane / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D007476:Ionophores / Q000494:pharmacology; D008563:Membrane Lipids / Q000378:metabolism*; D009550:Nigericin / Q000494:pharmacology*; D019301:Oleic Acid / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D027961:Potassium-Hydrogen Antiporters; D051381:Rats; D017207:Rats, Sprague-Dawley; D012156:Reticulocytes / Q000378:metabolism*; D013109:Sphingomyelins / Q000378:metabolism*
D017920:Antiporters; D005227:Fatty Acids; D007476:Ionophores; D008563:Membrane Lipids; D010713:Phosphatidylcholines; D027961:Potassium-Hydrogen Antiporters; D013109:Sphingomyelins; D019301:Oleic Acid; D009550:Nigericin; D011188:Potassium