Mechanism of thermal adaptation of membrane lipids in Tetrahymena pyriformis NT-1. Possible evidence for temperature-mediated induction of palmitoyl-CoA desaturase.
The regulatory mechanism of a key enzyme, palmitoyl-CoA desaturase, involved in the adaptation to temperature shift was investigated by labeling Tetrahymena pyriformis cells with [14C]palmitic acid. The rate of conversion of [14C]palmitate to [14C]palmitoleate was shown to be dependent on incubation temperature and also to be maximal at 2 h after the shift 39.5 to 15 degrees C. Addition of cycloheximide before the temperature shift produced no increase in desaturation of [14C]palmitate after the shift. These data would provide evidence for temperature-triggered increase of palmitoyl-CoA desaturase level and are also discussed in relation to membrane fluidity.
D000222:Adaptation, Physiological; D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D003513:Cycloheximide / Q000494:pharmacology; D004790:Enzyme Induction / Q000187:drug effects; D044943:Fatty Acid Desaturases / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism*; D010168:Palmitates / Q000378:metabolism; D010171:Palmitoyl Coenzyme A; D010743:Phospholipids / Q000378:metabolism; D013696:Temperature; D013769:Tetrahymena pyriformis / Q000502:physiology* / Q000648:ultrastructure
D008563:Membrane Lipids; D010168:Palmitates; D010743:Phospholipids; D010171:Palmitoyl Coenzyme A; D003513:Cycloheximide; D044943:Fatty Acid Desaturases