Glutamine metabolism and interactions with mechanistic target of rapamycin complex 1 in porcine preimplantation embryos

The ability to culture embryos has created opportunities for animal agriculture, including the refined selection of superior genetics, and for the medical field, allowing couples experiencing infertility to have biological children. Moreover, culturing embryos has led to the generation of numerous genetically modified models for improving production agriculture as well as studying genetic diseases in humans and testing novel therapeutics. Preimplantation embryos exhibit the ability to adapt to different culture conditions; however, cultured embryos are developmentally delayed and often less viable than those developing in vivo. Moreover, there is a significant amount of embryonic loss that occurs during the first few weeks of gestation, especially in pregnancies containing in vitro-produced embryos. Therefore, our overall goal is to understand the ways in which porcine preimplantation embryos use components of the culture medium so that we can modify conditions to improve development and increase the success of establishing pregnancies. The first aim was to determine if there was a deficiency of glutamine in our culture medium which was indicated by a previous transcriptional profiling dataset. The second aim was to investigate if glutamine acted as a signaling molecule in porcine preimplantation embryos to activate mechanistic target of rapamycin complex 1 (mTORC1), the main growth-regulating complex in cells. The final aim was to elucidate the role of a key enzyme in glutamine metabolism, glutaminase, during development to the blastocyst stage and subsequent elongation of porcine conceptuses as well as interactions with mTORC1. These studies provided insight into amino acid metabolism and regulation of cell signaling pathways as a basis for understanding the impact of the culture system on an embryo.Includes bibliographical references