split-intein Gal4 provides intersectional genetic labeling that is fully repressible by Gal80

Area of Science:

• Genetics and Molecular Biology
• Developmental Biology
• Neuroscience

Background:

• The split-Gal4 system in Drosophila enables precise genetic labeling of specific cell types.
• Existing split-Gal4 systems lack temporal control, limiting their application in time-sensitive genetic manipulations.
• Temporal control is crucial for many genetic experiments, including those requiring specific manipulation timing.

Approach:

• Developed a novel split-Gal4 system utilizing a self-excising split-intein for transgene expression.
• Demonstrated the system's efficacy through fluorescent reporters and reversible tumor induction in Drosophila.
• Extended the system to a drug-inducible GeneSwitch variant for independent inducible control.
• Introduced a new algorithm (Two Against Background or TAB) for predicting cell-type specific gene pairs from scRNAseq data.

Key Points:

• The new split-intein Gal4 system achieves strong transgene expression comparable to existing methods.
• This system is fully repressible by Gal80, allowing for precise temporal control of genetic manipulations.
• The system integrates with single-cell RNA sequencing (scRNAseq) data to design highly specific genetic drivers.
• A plasmid toolkit is provided for efficient creation of split-intein Gal4 drivers.

Conclusions:

• The split-intein Gal4 system provides a powerful tool for creating inducible and repressible, highly specific genetic drivers in Drosophila.
• This advancement overcomes limitations of previous split-Gal4 systems, enabling new experimental possibilities.
• The system facilitates the design of genetic tools informed by scRNAseq, enhancing research in Drosophila genetics.