Transcriptomic analysis of bovine endometrial epithelial cells in response to interferon tau and hormone stimulation
The embryonic loss during early stage of gestation is one of the major causes of infertility for domestic ruminants, causing huge economic losses to pasture. Maternal recognition of pregnancy and implantation are the crucial process for determining the successful establishment and development of pregnancy in cattle. The research on molecular mechanisms of pregnancy recognition will facilitate illustrating the complex process of pregnancy establishment and help to improve pregnancy outcomes. In this study, we performed transcriptomic analysis of primary bovine endometrial epithelial cells (BEND) with or without IFNT and hormones intervention through RNA sequencing. We eventually identified 608 differentially expressed genes (DEGs) including 409 up-regulated genes and 199 down-regulated genes in IFNT and hormones-treated group compared with control group. Gene Ontology (GO) enrichment analysis demonstrated that the majority of DEGs were implicated in immune system process, response to external stimulus, response to cytokine, regulation of response to stress. Results from KEGG analysis showed a significant enrichment of NOD-like receptor signaling pathway, antigen processing and presentation, necroptosis, oxidative phosphorylation, RIG-I-like receptor signaling pathway. Additionally, a set of promising candidate genes, including (USP18, STAT1, PSMB8, IFIH1, MX2, IFI44, DHX58, CASP8, DRAM1, CXCR4), were characterized by constructing an integrated interaction network. Overall design: To investigate the gene-interaction network and underlying molecular mechanisms regulating maternal recognition of pregnancy in ruminants, we established primary bovine endometrial epithelial cells (BEND), and performed RNA-seq to dissect the changes of gene expression profile in BEND under the combinatory treatment of IFNT, P4 and E2. The BEND were cultured with DMEM/F12 containing 10% FBS and 1% penicillin-streptomycin, and  divided into three groups of three replicates, which includes cells of control group (CON group), cells treated with E2 and P4 (GA group), cells treated with E2, P4 and IFNT (GB group) for sequencing. Comparative gene expression profiling analysis of RNA-seq data for BEND were performed.