Expression of aquaporins in human embryos and potential role of AQP3 and AQP7 in preimplantation mouse embryo development.

BACKGROUND/AIMS: Water channels, also named aquaporins (AQPs), play crucial roles in cellular water homeostasis. METHODS: RT-PCR indicated the mRNA expression of AQPs 1-5, 7, 9, and 11-12, but not AQPs 0, 6, 8, and 10 in the 2∼8-cell stage human embryos. AQP3 and AQP7 were further analyzed for their mRNA expression and protein expression in the oocyte, zygote, 2-cell embryo, 4-cell embryo, 8-cell embryo, morula, and blastocyst from both human and mouse using RT-PCR and immunofluorescence, respectively. RESULTS: AQP3 and AQP7 were detected in all these stages. Knockdown of either AQP3 or AQP7 by targeted siRNA injection into 2-cell mouse embryos significantly inhibited preimplantation embryo development. However, knockdown of AQP3 in JAr spheroid did not affect its attachment to Ishikawa cells. CONCLUSION: These data demonstrate that multiple aquaporins are expressed in the early stage human embryos and that AQP3 and AQP7 may play a role in preimplantation mouse embryo development.