Cre-mediated site-specific gene integration for consistent transgene expression in rice

Area of Science:

• Plant biotechnology
• Molecular biology
• Genetics

Background:

• Transgenic line development often suffers from expression variability due to random gene insertion.
• Minimizing expression variation is crucial for reliable genetic studies and crop improvement.

Purpose of the Study:

• To evaluate Cre/lox-mediated site-specific gene integration for reducing expression variability in transgenic rice.
• To compare gene expression patterns between site-specific single-copy and multicopy lines.

Main Methods:

• Utilized Cre/lox-mediated site-specific integration for precise transgene insertion.
• Employed biolistic DNA delivery to generate transgenic rice lines.
• Analyzed gusA reporter gene expression in callus and regenerated plants.

Main Results:

• Generated site-specific integrant lines, with ~80% showing precise gusA integration.
• Single-copy (SC) lines exhibited significantly lower expression variation compared to multicopy (MC) lines.
• Stable inheritance of the gusA gene was confirmed in T1 generation from SC lines.

Conclusions:

• Cre/lox-mediated site-specific integration effectively minimizes transgene expression variability in rice.
• Site-specific integration offers a reliable strategy for developing transgenic rice with consistent gene expression.
• This approach is valuable for stable genetic modification in rice breeding programs.