Stem cell factor/c-Kit signaling in in vitro cultures supports early mouse embryonic development by accelerating proliferation via a mechanism involving Akt-downstream genes

Abstract

Stem cell factor (SCF)/c-Kit regulates the proliferation and survival of germ cells or stem cells; however, little is known about the role of SCF/c-Kit in pre-implantation embryo development. Using exogenous SCF supplementation and c-Kit siRNA injection, we investigated the role and mechanism of SCF/c-Kit in pre-implantation mouse embryos. Addition of soluble SCF to the culture medium improved blastocyst formation. c-Kit gene silencing reduced the rate of blastocyst formation and delayed embryonic development. The number of proliferating cells in c-Kit gene-silenced blastocysts decreased, whereas the number of apoptotic cells in blastocysts obtained from both experimental and the control groups was not affected. RT-PCR, immunostaining and western blotting revealed that proliferation-related Akt downstream targets were substantially affected by c-Kit gene silencing. SCF/c-Kit signaling through Akt downstream targets is likely involved in mediating the cleavage and proliferation of blastomeres during mouse pre-implantation embryogenesis.