Transgenic rescue of SF-1-null mice

Area of Science:

• Endocrinology
• Molecular Biology
• Genetics

Background:

• Steroidogenic factor 1 (SF-1) is an essential orphan nuclear receptor for adrenal and gonad development and endocrine regulation.
• Understanding SF-1's function and expression control is vital for reproductive health and endocrine research.

Purpose of the Study:

• To identify critical transcriptional control regions of the Ftz-F1 gene.
• To elucidate functional roles of SF-1 in development and reproduction using a transgenic rescue strategy.

Main Methods:

• Generated transgenic mice using a rat yeast artificial chromosome containing the Ftz-F1 gene.
• Assayed rat SF-1 mRNA expression to evaluate transgene targeting.
• Created SF-1-deficient/transgene-positive "rescue" mice to assess developmental and reproductive rescue.

Main Results:

• Identified a critical transcriptional element for pituitary and hypothalamic expression located 3' to intron 4 of the Ftz-F1 locus.
• Demonstrated that an approximately 153-kb region of the Ftz-F1 locus can recapitulate most endogenous SF-1 allele activity.
• Observed defects in androgen-dependent tissues and Leydig cell differentiation in a hypomorphic rescue line, indicating distinct SF-1 roles in fetal and adult Leydig cells.

Conclusions:

• The study successfully mapped key regulatory regions of the Ftz-F1 gene, enhancing understanding of SF-1 transcriptional control.
• The findings highlight the complex roles of SF-1 in both early development and adult reproductive function, particularly in Leydig cells.