Global gene expression profile of interspecies pregnant implantation sites between rat and mouse

In present, interspecies cloning and interspecies-pregnancy were studied for endangered species rescue. However, the low implantation and survival ratio, spontaneous abortion, and unknown reason embryos absorption are the common and difficult problems of interspecies-pregnancy. In order to discover the mechanism of interspecies-pregnant failure and find ways to overcome the xeon-pregnant obstacles, we chosen the rat embryos pregnant in mouse uterus as a interspecies-pregnancy model. Three groups were set, mouse embryos to mouse recipients (MM) as control group, rat embryos to mouse recipients (RM), and rat and mouse embryos to mouse recipients together (RMM) as experiment groups. The former studies showed that rat embryos live no longer than day 7 of mouse pregnancy (D7). Our results showed that rat embryos survived to D7, and still existed to day 9 of mouse pregnancy (D9) in RM group. Surprisingly, the rat embryos survived to day 13 of the mouse gestation (D13) in RMM group. Microarray analysis was used to detect the global-gene expression profile changes of the whole implantation sites among the three groups at D7 and D9. By this way, we screened out the genes promoting the implanted rat embryos development in a mouse uterus which helped the rat embryos survive to D13 in RMM group compared with RM group, and the genes hindering the rat embryos development in a mouse uterus which prevented rat embryos living longer than D7 in RM group and D13 in RMM group compared with MM group. These findings provide insights into the mechanism of interspecies pregnant failure and new idea for interspecies pregnant studies.

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