Nonpolar Lipids in Yeast: Synthesis, Storage, and Degradation
摘要
The major nonpolar lipids occurring in yeast are triacylglycerols and steryl esters. These storage lipids accumulate when cells are provided with an excess of nutrients. As substantial amounts of nonpolar lipids cannot be incorporated into biomembranes, they are sequestered from the cytosolic environment in organelles called lipid droplets. Upon requirement, storage lipids are mobilized from this compartment by triacylglycerol lipases and steryl ester hydrolases. The respective degradation products serve as energy sources and/or building blocks for membrane formation. In this chapter, the reader is introduced to different mechanisms of triacylglycerol and steryl ester synthesis, storage of these lipids in lipid droplets, and their subsequent mobilization. Finally, major gaps in our current knowledge about nonpolar lipid metabolism and research needs for a better understanding of nonpolar lipid turnover are highlighted.