Linking post-translational modifications and variation of phenotypic traits

Area of Science:

• Biochemistry
• Yeast Genetics
• Proteomics

Background:

• Enzymes undergo post-translational modifications, generating isoforms with distinct properties.
• The phenotypic impact of quantitative variation in enzyme isoforms remains largely unexplored.
• Understanding these variations is crucial for comprehending cellular function and adaptation.

Purpose of the Study:

• To investigate the relationship between enzyme and isoform abundances in alcoholic fermentation.
• To correlate these abundances with metabolic and growth traits in Saccharomyces cerevisiae.
• To explore the role of post-translational modifications and human selection in shaping these traits.

Main Methods:

• Quantitative proteomics was employed to analyze enzyme and isoform abundances.
• Saccharomyces cerevisiae strains from various food-processing origins were studied across different culture media.
• Statistical analyses were performed to associate isoform variations with phenotypic traits.

Main Results:

• The total enzyme pool for fermentation remained constant, but individual enzyme and isoform abundances varied.
• Significant associations were found between the abundance of certain isoforms and metabolic/growth traits.
• N-terminal acetylation of alcohol dehydrogenase strongly correlated with cell size and maximum population size.
• Human selection, via differential targeting of isoforms, influenced the fermentation proteome.

Conclusions:

• Post-translational modifications significantly contribute to the diversity of metabolic and life-history traits in yeast.
• Isoform abundance variability, not just total enzyme levels, impacts yeast phenotypes.
• Human selection has played a role in shaping yeast fermentation capabilities through isoform-specific modifications.