Characterisation of mouse interferon-induced transmembrane protein-1 gene expression in the mouse uterus during the oestrous cycle and pregnancy

Abstract

During the oestrous cycle, pregnancy and parturition, the uterus undergoes marked morphological, physiological and functional changes. Amid these changes, the Wnt/β-catenin signalling pathway has been identified as having a crucial role in regulating associated biological events. Recently, based on results from a mouse embryo study, interferon-induced transmembrane protein 1 (Ifitm1) was reported as a downstream molecule of the Wnt/β-catenin signalling pathway. Differential expression patterns of the Ifitm1 gene during the oestrous cycle, pregnancy and parturition were identified in the present study. Quantitative real-time polymerase chain reaction data from uterine samples of mice induced start the oestrous cycle by injection of human chorionic gonadotropin (hCG) and revealed that Ifitm1 mRNA expression increased from late pro-oestrus to metoestrus, and decreased during dioestrus and early pro-oestrus. During pregnancy, Ifitm1 gene expression was minimal until parturition, but increased markedly 2 days after parturition. This significant elevation in Ifitm1 gene expression at post partum stage was identical to Ifitm1 expression after the induction of abortion by injection of prostaglandin F(2α). Interestingly, pregnant mare serum gonadotropin (PMSG) and oestrogen are also facilitates changes in Ifitm1 gene expression in an ovariectomised (OVX) mouse model. Expression of Ifitm1 mRNA was higher in response to PMSG than other hormones investigated. These results suggest that Ifitm1 may be involved in uteri physiology, although the mechanisms involved in the regulation of this gene expression and function in the uterus remain unknown. In the present study, differential expression patterns of the Ifitm1 gene were identified in the uteri of mice and the correlation between the patterns of Ifitm1 gene expression and Wnt/β-catenin signalling discussed.