Temperature-sensitive Saccharomyces cerevisiae mutant defective in lipid biosynthesis

Area of Science:

• Cell Biology
• Biochemistry
• Yeast Genetics

Background:

• Lipid biosynthesis is essential for cellular integrity and function.
• Temperature-sensitive mutants are valuable tools for studying essential genes and pathways.

Purpose of the Study:

• To characterize a novel temperature-sensitive mutant (DAM303) of Saccharomyces cerevisiae with defects in lipid biosynthesis.
• To investigate the relationship between lipid biosynthesis defects and other cellular processes like protein secretion and macromolecular synthesis.

Main Methods:

• Characterization of a temperature-sensitive yeast mutant (DAM303).
• Analysis of lipid biosynthesis by measuring the incorporation of 32Pi and [1-14C]acetate.
• Assessment of invertase secretion and complementation tests with the sec13 mutation.

Main Results:

• The DAM303 mutant exhibits rapid loss of viability and reduced lipid synthesis at 37°C.
• Accumulation of free fatty acids and impaired phospholipid synthesis were observed.
• Loss of invertase secretion occurred after the defect in phospholipid synthesis, and the mutation did not complement sec13.
• Methods for enriching temperature-sensitive mutants with lipid biosynthesis defects were developed.

Conclusions:

• Defects in lipid biosynthesis can directly impact protein secretion and other essential cellular functions in yeast.
• The DAM303 mutant provides a model for studying the consequences of impaired lipid synthesis.
• New strategies for identifying yeast mutants with lipid biosynthesis defects were established.