A Single-Component Optogenetic System Allows Stringent Switch of Gene Expression in Yeast Cells.

Area of Science:

• Synthetic biology
• Optogenetics
• Yeast genetics

Background:

• Light is a powerful tool for controlling cellular processes with high precision.
• Existing optogenetic systems often require multiple components or exogenous factors.
• Developing a simple, efficient light-inducible system is crucial for advancing biological research.

Purpose of the Study:

• To develop a novel, single-component light-switchable gene expression system for yeast.
• To characterize the performance of the system in terms of ON/OFF ratio, kinetics, and spatial resolution.
• To demonstrate the system's utility in controlling essential cellular functions and enabling bidirectional gene expression.

Main Methods:

• Development of the single-component yLightOn system in yeast.
• Characterization of gene expression ON/OFF ratios, leakage, and kinetics.
• Application of the system to regulate cell growth (His3) and cell cycle (^ΔN Sic1).
• Engineering and testing of a bidirectional expression module for simultaneous gene control.
• Demonstration of light-induced protein degradation using ssrA-tagged reporters (ClpX, ClpP).

Main Results:

• The yLightOn system achieved a >500-fold ON/OFF ratio with minimal leakage.
• Fast expression kinetics and high spatial resolution were observed.
• Precise control over cell growth and cell cycle progression was achieved.
• The bidirectional module enabled simultaneous light-controlled expression of two genes.
• Efficient and specific degradation of tagged proteins was demonstrated.

Conclusions:

• The single-component yLightOn system provides a robust and versatile tool for optogenetic control in yeast.
• This system facilitates precise regulation of gene expression, protein degradation, and cellular processes.
• The yLightOn system holds significant potential for advancing synthetic biology and understanding complex gene regulatory networks.