Inhibition, tissue distribution and hormonal specificity of a promoter-binding factor for the uteroglobin gene

We had earlier reported a uteroglobin promoter-binding factor in nuclei from progesterone-stimulated rabbit endometrium that was inhibited by a factor in nuclei without progesterone stimulation or from non-target tissues (Rider, V., and Bullock, D.W., 1988. Biochem. Biophys. Res. Comm. 156, 1368-1375). In the course of purification of the inhibitory activity, the effect was shown to be due to contaminating genomic DNA. The inhibitor was destroyed by treatment with DNase I and resisted phenol-chloroform extraction. Fractionation of nuclear extracts on columns of DEAE-Sepharose separated the inhibitor and revealed the presence of binding activity in unstimulated or estrogen-treated endometrium, as well as in liver, lung and ovary. The tissue and hormonal specificity of the promoter binding factor is thus less restricted than recently reported.