Dissecting timing variability in yeast meiosis

Area of Science:

• Cell Biology
• Developmental Biology
• Genetics

Background:

• Cell-to-cell variability in developmental timing can provide adaptive advantages for populations in fluctuating environments.
• Meiosis initiation in Saccharomyces cerevisiae is triggered by nutritional starvation.

Purpose of the Study:

• To investigate the sources of cell-to-cell variability in meiotic timing in Saccharomyces cerevisiae.
• To understand the regulatory mechanisms underlying this temporal variability.

Main Methods:

• Utilized time-lapse fluorescence microscopy to track meiotic events in individual yeast cells.
• Analyzed the relationship between cell-cycle progression, nutritional history, cell size, and meiotic timing.

Main Results:

• Observed significant cell-to-cell variability in the duration of meiosis.
• Identified that variability is primarily concentrated between starvation onset and early meiosis gene activation.
• Determined that the production rate and gradual increase of the meiotic regulator Ime1, influenced by cell size, govern this timing variability.

Conclusions:

• Phenotypic variability in meiotic timing is directly linked to the expression dynamics of the transcriptional regulator Ime1.
• The study provides a framework for understanding temporal processes in development, emphasizing the role of gene expression dynamics.