Sphingolipid synthesis involves a highly conserved biosynthetic pathway that produces
fundamental precursors of complex sphingolipids. The final reaction involves the insertion of
a double bond into dihydroceramides to generate the more abundant ceramides, which are
converted to sphingomyelins and glucosylceramides/gangliosides by the addition of polar
head groups. Although ceramides have long been known to mediate cellular stress
responses, the dihydroceramides that are transiently produced during de novo sphingolipid …