An Alternative Pathway for the Enzymatic Synthesis of Sphingomyelin

Signaling pathways for sphingosylphosphorylcholine-mediated mitogenesis in Swiss 3T3 fibroblasts.

“…Earlier, SPC had been proposed to be a potential precursor of sphingomyelin. Brady et al first reported the formation of [t4C]sphingomyelin after incubation of SPC and stearoyl-[t4C]CoA with rat brain homogenates (Brady et al, 1965). SPC was recently reported to stimulate an increase in sphingomyelin levels in neuroblastoma cells (Sugiyama et al, 1990) and in human leukemia HL-60 cells (Dressier et al, 1991).…”

Enzymic synthesis of cerebroside from ceramide and uridine diphosphate galactose

“…It was reported by Brady (1962) that the formation of cerebroside (ceramide-galactose) occurred via a reaction between psychosine (sphingosinegalactose) and acyl-CoA in a microsomal preparation obtained from young rat brain. Two pathways are now known for the biosynthesis of sphingomyelin (ceramide-phosphorylcholine): one by transfer of acyl group from acyl-CoA to sphingosylphosphorylcholine (Brady, Bradley, Young & Kaller, 1965;) and the other through transfer of the phosphorylcholine moiety from CDP-choline to ceramide (N-acylsphingosine) (Sribney & Kennedy, 1958;Fujino, Nakano, Negishi & Ito, 1968). Since the known pathway for the synthesis of cerebroside is analogous to the former synthetic reaction for sphingomyelin, it was decided to test whether an alternative pathway might exist for cerebroside formation.…”

Role of a specific choline pool in sphingomyelin synthesis in rat heart

“…The exclusive role of cytidine diphosphate choline as precursor in the biosynthesis of sphingomyelin (Kennedy & Weiss, 1956;Sribney & Kennedy, 1958;Brady et al, 1965;Sribney, 1968;Fujino et al, 1968) is the subject of debate. In mouse cells transformed with SV 40 virus, a new pathway of sphingomyelin synthesis via phosphatidylcholine has been demonstrated that involves the transfer of the phosphorylcholine group (Marggraf et al, 1972;Diringer et al, 1972;Diringer, 1973;Diringer & Koch, 1973;Marggraf & Anderer, 1974).…”