Next Generation Sequencing Facilitates Quantitative Analysis of Endometrium Transcriptomes During Porcine Embryo Implantation.. Sus scrofa

In this study, deep sequencing of endometrial RNA samples during early pregnancy were performed using RNA sequencing (RNA-Seq). The changes of genes expressed among three stages (day 12, 18 and 25) of pregnancy were investigated by the multiple comparisons. Analysis of reads, between 1557 and 8951 differentially expressed genes (DEGs) were revealed among different periods of implantation. Expression of selected genes was validated by the use of quantitative real-time RT-PCR. Bioinformatics analysis of differentially expressed genes in the endometrium revealed a number of biological processes and pathways potentially involved in embryo implantation in the pig, most noticeably cell proliferation, regulation of immune response, interaction of cytokine-cytokine receptor, and cell adhesion. This revealed specific gene expression patterns reflecting the different functions of the endometrium on three stages (maternal recognition, conceptus attachment and embryo implantation). This study identified comprehensive transcriptomic profile in the porcine endometrium, it could be a foundation for targeted studies of genes and pathways potentially involved in abnormal endometrial receptivity and embryo loss in early pregnancy. Overall design: Porcine endometrium mRNA profiles during early pregnancy were generated by deep sequencing using Illumina Hiseq2000.