A conditional counterselectable Piga knockout in mouse embryonic stem cells for advanced genome writing applications

Area of Science:

• Mammalian genetics
• Molecular biology
• Genome engineering

Background:

• Counterselectable markers are crucial for genome engineering, but a lack of robust markers hinders mammalian applications.
• Efficient removal or replacement of DNA sequences requires effective negative selection strategies.

Purpose of the Study:

• To develop a novel conditional knockout strategy for a robust counterselectable marker in mouse embryonic stem cells.
• To enable efficient genome engineering in mammals without compromising developmental potential.

Main Methods:

• Developed a conditional Piga knockout strategy in mouse embryonic stem cells.
• Utilized proaerolysin-based counterselection.
• Demonstrated restoration of native Piga function for development.
• Engineered a conditional knockout of Hprt to show strategy generality.

Main Results:

• Conditional Piga knockout cells exhibit robust proaerolysin resistance, comparable to full Piga deletion.
• The PIGA transgene can be effectively used as a counterselectable marker.
• Native Piga function is successfully restored, facilitating subsequent mouse development.
• The strategy is applicable to other genes, such as Hprt.

Conclusions:

• The conditional Piga knockout strategy provides an efficient tool for mammalian genome engineering.
• This method facilitates advanced mouse genome writing and the establishment of novel mouse models.
• The approach addresses the bottleneck of limited counterselectable markers in developmental biology.