Regulation of Cyclic AMP-Response Element Binding Protein Zhangfei (CREBZF) Expression by Estrogen in Mouse Uterus.

CREBZF (cAMP-response element binding protein zhangfei) is a member of ATF/CREB family, and which regulates various cellular functions by suppressing major factors with direct interaction. In this study, we have examined the expression of CREBZF on mouse endometrium during uterus estrous cycles and estrogen (E2) treatment. In uterus, CREBZF mRNA expression was higher than other organs and mRNA and protein of CREBZF was increased in proestrus phase and decreased in estrus phase. The expression of CREBZF in 3-weeks old mouse uterus was reduced by E2 injection in endometrium. In addition, the expression of progesterone receptor, a marker of E2 in ovariectomized mice was found to be strongly expressed in stroma, while CREBZF was only expressed in epithelium. Also, we conformed that E2-suppressed CREBZF was restored by co-injection of ICI 182,780, an estrogen receptor antagonist. Overall, these results suggest that CREBZF is regulated by estrogen and involved in ER signaling pathway in mouse uterus.