Phospholipid Catabolism and Phospholipid Turnover in Cultured Cells
Phosphatidylcholine (PC) and sphingomyelin (SM) constitute >50% of the phospholipids of most mammalian cell membranes1. They differ in many of their physical properties and variations in their relative proportions have profound effects on the membrane bilayer1,2. The differences in physical properties are determined in part by variations in acyl chain composition and result in micro-heterogeneity within each choline-lipid class. The relative proportions of these subspecies of the two major choline-lipid classes, and of the two major choline-lipid species themselves is controlled by synthetic and degradative enzymes. Both synthesis and degradation are continuous processes and are reflected in a high rate of turnover of PC and SM. As the amount of choline lipid per mg protein is relatively constant in the cell, there must be a close co-ordination between the synthetic and degradative pathways to maintain an appropriate balance. The nature of the interactions between these two processes is largely unknown.
KeywordsNeuroblastoma Cell Newborn Calf Serum Metachromatic Leukodystrophy Culture Neuroblastoma Cell Degradative Rate
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