Comparative transcriptome analysis of embryo invasion in the mink uterus

In mink, as many as 65% of embryos die during gestation. The causes and the mechanisms of embryonic mortality remain unclear. The purpose of our study was to examine global gene expression changes during embryo invasion in mink, and thereby to identify potential signaling pathways involved in implantation failure and early pregnancy loss.

Illumina's next-generation sequencing technology (RNA-Seq) was used to analyze the differentially expressed genes (DEGs) in implantation (IMs) and inter-implantation sites (inter-IMs) of uterine tissue.

We identified a total of 606 DEGs, including 420 up- and 186 down-regulated genes in IMs compared to inter-IMs. Gene annotation analysis indicated multiple biological pathways to be significantly enriched for DEGs, including immune response, ECM complex, cytokine activity, chemokine activity and protein binding. The KEGG pathway including cytokine-cytokine receptor interaction, Jak-STAT, TNF and the chemokine signaling pathway were the most enriched. A gene network was constructed, and hub nodes such as CSF3, ICAM1, FOS, IL1B, IL8, CD14 and MYC were found through network analysis.

This report provides a valuable resource for understanding the mechanisms of embryo implantation in mink.