Maternal embryokines that regulate development of the bovine preimplantation embryo

Abstract

Proper embryonic development depends upon regulatory signals from the reproductive tract called embryokines. This review uses the cow as a model to understand the developmental processes controlled by embryokines. The focus is on 3 embryokines that have been shown to increase competence of embryos to survive after transfer to recipients: CSF2, IGF1, and DKK1. Together, these molecules regulate key events required for development of the embryo to the blastocyst stage including proliferation (enhanced by IGF1), development of the inner cell mass (regulated by CSF2), control of differentiation (modified by DKK1), and inhibition of apoptosis and stress-mediated developmental arrest (IGF1 and CSF2).