Isolation of mutant Saccharomyces cerevisiae strains that survive without sphingolipids.
Sphingolipids comprise a large, widespread family of complex eucaryotic-membrane constituents of poorly defined function. The yeast Saccharomyces cerevisiae is particularly suited for studies of sphingolipid function because it contains a small number of sphingolipids and is amenable to molecular genetic analysis. Moreover, it is the only eucaryote in which mutants blocked in sphingolipid biosynthesis have been isolated. Beginning with a nonreverting sphingolipid-defective strain that requires the addition of the long-chain-base component of sphingolipids to the culture medium for growth, we isolated two strains carrying secondary, suppressor mutations that permit survival in the absence of exogenous long-chain base. Remarkably, the suppressor strains made little if any sphingolipid. A study of how the suppressor gene products compensate for the lack of sphingolipids may reveal the function(s) of these membrane lipids in yeast cells.
Dickson
R C
RC
Department of Biochemistry, University of Kentucky, Lexington 40536-0084.
Wells
G B
GB
Schmidt
A
A
Lester
R L
RL
D015139:Blotting, Southern; D004271:DNA, Fungal / Q000235:genetics; D005227:Fatty Acids / Q000378:metabolism; D007294:Inositol / Q000378:metabolism; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D013107:Sphingolipids / Q000502:physiology*; D013489:Suppression, Genetic
D004271:DNA, Fungal; D005227:Fatty Acids; D013107:Sphingolipids; D007294:Inositol