Storage lipid synthesis is non-essential in yeast.
Steryl esters and triacylglycerol (TAG) are the main storage lipids in eukaryotic cells. In the yeast Saccharomyces cerevisiae, these storage lipids accumulate during stationary growth phase within organelles known as lipid bodies. We have used single and multiple gene disruptions to study storage lipid synthesis in yeast. Four genes, ARE1, ARE2, DGA1, and LRO1, were found to contribute to TAG synthesis. The most significant contribution is made by DGA1, which encodes a novel acyl-CoA:diacylglycerol acyltransferase. Two of the genes, ARE1 and ARE2, are also involved in steryl ester synthesis. A yeast strain that lacks all four genes is viable and has no apparent growth defects under standard conditions. The strain is devoid of both TAG and steryl esters, and fluorescence microscopy revealed that it also lacks lipid bodies. We conclude that neither storage lipids nor lipid bodies are essential for growth in yeast.
Sandager
Line
L
Department of Crop Science, Swedish University of Agricultural Sciences, Box 44, S-230 53 Alnarp, Sweden.
Gustavsson
Maria H
MH
Ståhl
Ulf
U
Dahlqvist
Anders
A
Wiberg
Eva
E
Banas
Antoni
A
Lenman
Marit
M
Ronne
Hans
H
Stymne
Sten
S
D000217:Acyltransferases / Q000235:genetics; D056850:Cyclin-Dependent Kinase 8; D018844:Cyclin-Dependent Kinases / Q000235:genetics; D051048:Diacylglycerol O-Acyltransferase; D005227:Fatty Acids / Q000096:biosynthesis*; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics; D005800:Genes, Fungal; D005838:Genotype; D015388:Organelles / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D014280:Triglycerides / Q000096:biosynthesis*
D005227:Fatty Acids; D005230:Fatty Acids, Nonesterified; D005656:Fungal Proteins; D029701:Saccharomyces cerevisiae Proteins; D014280:Triglycerides; D000217:Acyltransferases; C494880:DGA1 protein, S cerevisiae; D051048:Diacylglycerol O-Acyltransferase; D056850:Cyclin-Dependent Kinase 8; D018844:Cyclin-Dependent Kinases; C498309:SSN3 protein, S cerevisiae