Interferon regulatory factors (IRFs) repress transcription of the chicken ovalbumin gene.

Although the ovalbumin (Ov) gene has served as a model to study tissue-specific, steroid hormone-induced gene expression in vertebrates for decades, the mechanisms responsible for regulating this gene remain elusive. Ov is repressed in non-oviduct tissue and in estrogen-deprived oviduct by a strong repressor site located from -130 to -100 and designated CAR for COUP-TF adjacent repressor. The goal of this study was to identify the CAR binding protein(s).

Estrogen action: revitalization of the chick oviduct model.

Despite decades of investigation, the molecular pathways triggered by estrogen that lead to tissue-specific cell proliferation, differentiation and survival are only superficially understood. If we are to modulate the actions of estrogen selectively in these processes, continued investigation using biologically relevant models is essential. The chick oviduct emerged as an early model for investigating the mechanism of action of steroid hormones because of its exquisite responsiveness to them.

Comparison of the responsiveness of the pGL3 and pGL4 luciferase reporter vectors to steroid hormones.

The ovalbumin gene (Ov) gene is responsive to estrogen, glucocorticoid, androgen, and progesterone. In our efforts to characterize the regulation of the Ov gene by steroid hormones, we have repeatedly observed that many vector backbones and promoters are responsive to steroids. In order to determine which vectors are most suitable for these types of analyses, vectors from Promega's pGL3 and newly engineered pGL4 Dual-Luciferase Reporter Assay System were tested with both estrogen and/or corticosterone.