The alterations in endometrial and myometrial transcriptome at the time of maternal recognition of pregnancy in pigs

The maternal recognition of pregnancy in pigs occurs around day 12-13 of gestation. During this period embryo-derived signals act on the endometrium and the myometrium to trigger tissue-specific responses that lead to proper implantation and maintenance of pregnancy. The present study utilized gene expression microarrays to examine embryo-induced alterations in porcine endometrial and myometrial transcriptome on days 12-13 of pregnancy. It has been confirmed that the endometrium and the myometrium, in response to embryonic signals, express unique set of genes. However, a key discovery of this study is the fact that genes that encode crucial factors involved in maternal recognition of pregnancy and preparation of uterus for implantation are regulated similarly in both tissues. Genes responsible for PGs synthesis (PTGES2, PTGR2), uterine development and remodeling (HOXA10, GRB10, MTOR) and innate immune response and immunomodulation (NFKBIA, TRAFD1) were regulated similarly in the endometrium and the myometrium. This suggests that in pigs these tissues act in sync to support embryos during peri-implantation.