Early pregnancy loss is a feature of all mammals and is particularly high in women. It is a major public health concern. More than 50% of normally conceived pregnancies fail in the period at about the time the embryo attaches to the uterus and begins to implant. Among the causes are developmental abnormalities of the embryo, weak or late signaling from the trophectoderm (the precursor of the placenta) and an ill- prepared maternal uterus. Here we shall study two aspects of conceptus-maternal relationship in early pregnancy. The first (goal 1) is to define the role of the transcription factor Cdx2 in trophectoderm specification and functional differentiation.
Aim 1 A is to confirm that Cdx2 plays a key role in the transcriptional control of the genes for the signaling molecule interferon-tau (IFN-T) and other genes characteristically up-regulated in trophectoderm.
Aim 1 B will test the hypothesis that Cdx2 is necessary in directing trophectoderm emergence in murine and bovine embryos and in maintaining a polarized epithelium.
Aim 1 C will confirm preliminary studies that Cdx2 is a marker of presumptive trophectoderm as early as the 2-cell stage of development. We shall also determine whether it is an analogous marker of cell fate in the bovine embryo. Goal 2 of this project is to define the function of Sin1, a newly discovered protein that associates with carboxyl end of the cytoplasmic domain of the IFN receptor subunit, IFNAR2. We hypothesize that maternal recognition of pregnancy involves a localized inflammatory response and the modulation of stress pathways in maternal endometrium at the site of implantation, and that Sin1 links the IFN response pathway to signal transduction pathways, including the stress-activated protein kinase (SAPK) pathway.
Aim 2 A is to define partners for Sin1 in endometrial signaling through the use of a yeast two-hybrid screen.
Aim 2 B will test the hypothesis that when IFN-T binds to the cell surface of uterine epithelial cells Sin 1 will be recruited, and this event will precede changes in the activities of stress-activated signal transduction pathways.
Aim 2 C will examine whether there is cellular relocation of Sin1 following IFN-T binding to the cell.
Aim 2 D will attempt to knock down Sin1 expression by RNAi and, by using this approach, determine whether Sin1 plays a role in some of the varied (pleiotropic) actions of type I IFN on mammalian cells.
Aim 2 E will explore whether the over-expression of different domains of the Sin1 protein can interfere with normal Sin1 function.
Aim 2 F is to create Sin1 null mice in order to gain a more complete insight into Sin1 function in the whole animal as well as in uterine endometrium. Together these studies are expected to provide information on two key events in early pregnancy, the formation of an early placenta and immediate maternal responses to the presence of a tiny embryo attaching to her uterine wall.

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Research Project (R01)
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Study Section
Cellular, Molecular and Integrative Reproduction Study Section (CMIR)
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Yoshinaga, Koji
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University of Missouri-Columbia
Veterinary Sciences
Schools of Earth Sciences/Natur
United States
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Ezashi, Toshihiko; Imakawa, Kazuhiko (2017) Transcriptional control of IFNT expression. Reproduction 154:F21-F31
Green, Mark P; Harvey, Alexandra J; Spate, Lee D et al. (2016) The effects of 2,4-dinitrophenol and d-glucose concentration on the development, sex ratio, and interferon-tau (IFNT) production of bovine blastocysts. Mol Reprod Dev 83:50-60
Gupta, Rangan; Ezashi, Toshihiko; Roberts, R Michael (2012) Squelching of ETS2 transactivation by POU5F1 silences the human chorionic gonadotropin CGA subunit gene in human choriocarcinoma and embryonic stem cells. Mol Endocrinol 26:859-72
Bermejo-Alvarez, Pablo; Rosenfeld, Cheryl S; Roberts, R Michael (2012) Effect of maternal obesity on estrous cyclicity, embryo development and blastocyst gene expression in a mouse model. Hum Reprod 27:3513-22
Bermejo-Alvarez, P; Roberts, R M; Rosenfeld, C S (2012) Effect of glucose concentration during in vitro culture of mouse embryos on development to blastocyst, success of embryo transfer, and litter sex ratio. Mol Reprod Dev 79:329-36
Ezashi, Toshihiko; Matsuyama, Haruyo; Telugu, Bhanu Prakash V L et al. (2011) Generation of colonies of induced trophoblast cells during standard reprogramming of porcine fibroblasts to induced pluripotent stem cells. Biol Reprod 85:779-87
Zhou, Liang; Wang, Wei; Liu, Yongqing et al. (2011) Differentiation of induced pluripotent stem cells of swine into rod photoreceptors and their integration into the retina. Stem Cells 29:972-80
Roberts, R Michael; Katayama, Mika; Magnuson, Scott R et al. (2011) Transcript profiling of individual twin blastomeres derived by splitting two-cell stage murine embryos. Biol Reprod 84:487-94
Roberts, R Michael; Fisher, Susan J (2011) Trophoblast stem cells. Biol Reprod 84:412-21
Schulz, Laura C; Roberts, R Michael (2011) Dynamic changes in leptin distribution in the progression from ovum to blastocyst of the pre-implantation mouse embryo. Reproduction 141:767-77

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