Abstract: Objective To investigate the expression pattern of ATF4 in mouse endometrium during the estrus cycle. Methods Reverse transcription polymerase chain reaction (RT- PCR), immunohistochemistry and Western blotting were respectively used to detect the expression of ATF4 mRNA and protein in mouse endometrium during each stage of the estrus cycle. Results The ATF4 mRNA expression in estrus stage was higher than those of the other 3 stages, and there was significant difference between estrus stage and the other 3 groups ( P <0.05) . The prominent expression of ATF4 protein was primarily limited to the glandular epithelium cell and luminal epithelium cell cytoplasm in the endometrium. Expression of ATF4 protein was similar with that of the mRNA. Conclusion ATF4, expressed in endometrium periodically in the estrus cycle, might play an important role in the endometrial cyclical variation during the estrus cycle.

Key words: ATF4, mice, estrus cycle, endometrium