Transactivation of Hox gene expression in a VP16-dependent binary transgenic mouse system

Area of Science:

• Developmental Biology
• Genetics
• Molecular Biology

Background:

• Aberrant Hox gene expression is crucial for understanding skeletal and nervous system development.
• Lethality in transgenic mice often hinders the study of Hox gene function during development.
• Existing transgenic models face challenges in controlling transgene expression and preventing premature death.

Purpose of the Study:

• To establish a binary transgenic mouse system for controlled Hox gene expression.
• To circumvent lethality associated with aberrant Hox gene expression in transgenic mice.
• To enable detailed in vivo analysis of developmental abnormalities caused by deregulated Hox genes.

Main Methods:

• Generation of transresponder mouse strains containing murine homeobox genes linked to a VP16-responsive immediate early (IE) promoter.
• Utilized a binary system with transactivator (VP16 gene) and transresponder (Hox gene) mice.
• Embryo microdissection and reverse transcription polymerase chain reaction (RT-PCR) analysis to assess transgene expression.

Main Results:

• Successful transcriptional activation of Hox-transgenes in progeny inheriting both transactivator and transresponder transgenes.
• Demonstrated spatially restricted expression of Hox-transgenes, correlating with VP16 presence in mouse embryos.
• The system allows for stable and reproducible activation of Hox-transgenes.

Conclusions:

• The developed binary transgenic system effectively controls Hox gene expression in vivo.
• This system overcomes the lethality issue, facilitating the study of Hox gene function in development.
• Enables precise dissection of molecular mechanisms underlying developmental abnormalities due to Hox gene dysregulation.