Sphingolipids are essential for the growth of Chinese hamster ovary cells. Restoration of the growth of a mutant defective in sphingoid base biosynthesis by exogenous sphingolipids.

摘要: We previously isolated a temperature-sensitive Chinese hamster ovary cell mutant (strain SPB-1) with thermolabile serine palmitoyltransferase, which is involved in the first step of sphingolipid synthesis (Hanada, K., Nishijima, M., and Akamatsu, Y. (1990) J. Biol. Chem. 265, 22137-22142). In this study, sphingolipid-deficient culture medium was used to examine effect exogenous sphingolipids on growth SPB-1. When cultivated medium, SPB-1 cells ceased growing at non-permissive temperatures. Under these conditions, de novo cells, resulting decrease levels sphingomyelin ganglioside sialyl lactosylceramide (GM3), whereas parental CHO-K1 grew logarithmically normal synthesis. Exogenous sphingosine restored contents both GM3 near through metabolic utilization allowed grow even temperature. Similarly, only partly also suppressed temperature-sensitivity growth. contrast, glucosylceramide, but not levels, failed suppress temperature sensitivity Combination ceramide, GM3, or sphingoid bases did show any synergistic additive enhancement, compared alone. The results indicated that due lack cellular sphingolipids, possibly sphingomyelin.