Dissertation - Open Access
Doctor of Philosophy (PhD)
Conceptus, Estradiol, Pregnancy, Proteomics, Transcriptomics, Uterus
Preovulatory estradiol has been reported to play a crucial role in pregnancy establishment and maintenance, but the mechanism by which estradiol exerts its effects has not been well characterized. Specifically, the interactions between the maternal uterine environment and the developing conceptus can greatly impact pregnancy success or loss. The objective of this dissertation is to determine the effects of preovulatory estradiol exposure on uterine and trophectoderm transcriptomes, and uterine luminal fluid (ULF) protein composition. Beef cows/heifers were synchronized, artificially inseminated (d 0), and grouped into either high (highE2) or low (lowE2) preovulatory estradiol. Uteri were flushed to collect d16 conceptuses either nonsurgically or following slaughter, and endometrial biopsies (n=29) were collected from the ipsilateral uterine horn. Real-Time PCR (RT-PCR) was performed on trophectoderm (TE; n=21) RNA to measure the relative abundance of IFNT, PTGS2, TM4SF1, C3, FGFR2, and GAPDH. Total cellular RNA was extracted from endometrium for RNA sequencing. ULF pools (n=28) for the following groups: highE2/noconceptus, highE2/conceptus, lowE2/noconceptus, and lowE2/conceptus were analyzed using a 2D LC-MS/MS based 8plex iTRAQ method. RT-PCR data were analyzed using the MIXED procedure in SAS. Transcript abundances in the endometrium were quantified using kallisto, differentially expressed genes (DEGs) were determined using DESeq2 (FDR <0.05, FC>2), and IPA was used for pathway analysis. Scaffold Q+ was used to quantitate peptide and protein identifications in the ULF. There were no differences in mRNA abundances in TE, but there were 432 DEGs among the highE2/conceptus versus lowE2/conceptus groups, 253 were downregulated (CR2, CDH4, TROAP, COL1A2) and 179 were upregulated (PRSS8, FABP3, IDO1, MUC13, CXCL10) in the highE2/conceptus group. There were 48 differentially expressed proteins (DEPs) among the highE2/conceptus and lowE2/conceptus groups (19 upregulated, 29 downregulated in the highE2/conceptus group), 6 of these were differentially expressed (FDR <0.10) at the mRNA level. Similar pathways for mRNA and proteins included: calcium signaling, protein kinase A signaling, and CRH signaling. These results demonstrate greater differences in uterine function than in conceptus developmental competence between highE2 and lowE2 animals on d16 of pregnancy.
Number of Pages
South Dakota State University
In Copyright - Educational Use Permitted
Northrop, Emmalee J., "The Influence of Preovulatory Estradiol on Uterine Transcriptomics and Proteomics Around Maternal Recognition of Pregnancy in Beef Cattle" (2019). Electronic Theses and Dissertations. 3355.