Gene regulation by a protein translation factor at the single-cell level

Area of Science:

• Molecular Biology
• Systems Biology
• Synthetic Biology

Background:

• Gene expression exhibits inherent stochasticity, with transcriptional regulation well-studied.
• Stochastic behavior in translationally regulated genes remains poorly understood.
• Understanding gene expression noise is crucial for cellular function and synthetic biology.

Purpose of the Study:

• To engineer and analyze a synthetic genetic system for studying translationally regulated gene expression noise.
• To quantify noise propagation and buffering in a system controlled at the protein translation level.
• To develop a mathematical model explaining the system's behavior and cell-to-cell variability.

Main Methods:

• Engineered a synthetic genetic circuit with a transcriptionally regulated translation factor.
• Monitored regulator and target gene expression at the single-cell level.
• Employed mathematical modeling and Gamma distribution analysis.

Main Results:

• Achieved tight repression of the target gene using the translation factor.
• Observed noise buffering from the regulator to the regulated gene.
• Demonstrated nonlinear sensitivity to global translation perturbations and captured cell-to-cell variability.

Conclusions:

• Translational control can effectively buffer gene expression noise.
• The developed system provides insights into stochastic gene expression.
• Findings offer design principles for creating robust synthetic gene circuits.