Blastocyst activation engenders transcriptome reprogram affecting X-chromosome reactivation and inflammatory trigger of implantation

Significance Our data systematically and comprehensively reveal the genetic programming of blastocyst for implantation in a delayed implantation mouse model. By analyzing the transcriptional profile, we demonstrate dynamic changes in the biosynthesis, metabolism, and cell proliferation during blastocyst reactivation from diapause. We have analyzed the global remodeling of ICM and TE, respectively, and disclosed the critical cellular and molecular events during implantation. Furthermore, our results suggest that an activating blastocyst functions as a proinflammatory body to trigger an inflammatory-like attachment response. Thus, we demonstrate a previously undefined role of blastocyst during implantation. We believe that the findings in this study substantially advance scientific understanding of the inflammatory-attachment response during implantation.