Analysis of the Development of insrr Knockout Mouse Preimplantation Embryos

Maintaining an optimal acid-base balance of the organism has a pivotal role in the regulation of metabolism. It is provided by the functioning of endogenous pH-sensors, the molecules with abilities to change their activity with the changes in the pH of the medium. Receptor tyrosine kinase IRR (insulin receptor-related receptor) is an alkaline pH sensor that is activated when the pH of the extracellular medium rises above 7.9. The expression of IRR is specific; the receptor is found in some organs, in certain types of cells. It has been established that the IRR receptor is involved in the excretion of bicarbonate by kidneys. The mechanism of action and function of the IRR receptor as an alkaline pH sensor in other organs is not understood yet. To reveal the role of the IRR receptor in the embryogenesis, we carried out experiments to evaluate the development of preimplantation embryos of wild-type and insrr knockout mice using the MEA (Mouse Embryo Assay) test. The development was assessed using the blastocyst yield index, the percentage of blastocyst formation from the total number of obtained zygotes. The yield of blastocysts in knockout animals was lower than in wild-type animals; it was 6.7% of the total number of extracted cells for knockout animals and 43.8% for wild-type animals. The number of obtained zygotes in case of wild-type and insrr knockout mice also differed. The average number of extracted zygotes from one female was 18.9 zygotes for wild-type mice and 11.8 zygotes for insrr knockout mice. Our results reveal a possible role for the receptor tyrosine kinase IRR in the development of preimplantation embryos.