Roles of Progesterone and Paternal Gene Expression on Embryo Development in Bovine

Fertility is the most important factor controlling mammalian reproduction. Bull fertility, ability of the sperm to fertilize and activate the egg, and support embryonic development is crucial for early development. Similarly, the hormonal environment of the embryo also plays a critical role in successful embryonic development. We know that molecular health of the sperm as well as progesterone enhancing the development of the embryo is important for early development and implantation. The gaps in the knowledge base are 1) how early mammalian embryo development is paternally affected is not fully clear and 2) how progesterone improves the survival of the transferred embryo in the uterus still remains elusive. The central hypothesis was that low expression of MHC1 and Magel2 would cause a dysfunction in early embryo development and that progesterone will increase the survivability of the embryo via its associations with TNF-alpha and PGF2alpha. The objectives of this study were to 1) determine the expression of mhc1 and magel2 in single in vivo and in vitro blastocysts derived from low fertility and high fertility sires as well as to determine main pathways by which protein products of these genes regulate early development, and 2) identify the role of progesterone in regulating TNF-alpha and PGF2alpha. To accomplish these goals, we performed real time reverse transcriptase reaction and bioinformatics approaches, and ELISA and commercially available radioimmunoassay kits, respectively. The results of the experiments showed that 1) expression of mhcI transcripts were greater in high fertility in vivo embryos compared to their low fertility in vivo counterparts. Magel2 results showed an increase (P ≤ 0.05) in expression levels of high fertility in vivo embryos compared to their high fertility in vitro counterparts. Low fertility in vivo embryos had higher expression than high fertility in vitro embryos as well