Spatiotemporal expression of S100A2 in peri-implantation mouse endometrium WANG Sheng1，LIU Zhenzhen1，TAN Yi1，ZHOU Lan2，TAN Dongmei1

Abstract:

Objective：To identify the expression pattern of S100A2 mRNA and protein in peri-implantation endometrium in mice，and to accumulate experimental proof which S100A2 might play roles in embryo implantation. Methods：mRNA and protein expression of S100A2 were detected by fluorescence quantitative polymerase chain reaction（FQ-PCR） and immunohistochemistry. Results：① S100A2 mRNA was steadily expressed in the mouse uterus during d1-d6 of pregnancy，and its quantity gradually decreased day by day. On d5 of pregnancy，its expression level was lower in the implantation sites than that in inter-implantation sites. ②S100A2 pro－tein was localized in cytoplasm of mouse endometrial stromal cells，while its level dynamically changed:strongly positive on d1-d2，weakly positive on d3-d5. ③No expression was detected in endometrial luminal epithelial cells and gland cells. Conclusion：Dynamic expression of S100A2 in mouse uterus during embryo implantation shows that it might play roles in regulation of embryo invasion into the uterine endometrium.