Data Sheet 1_Sperm TLR2/1 activation modulates the paternal RNA cargo and enhances bovine embryonic development.docx

However, IVP efficiency remains suboptimal, as in vitro-derived embryos frequently exhibit reduced developmental competence compared to their in vivo counterparts. Previous studies indicate that activation of the sperm Toll-like receptor 2/1 (TLR2/1) complex via Pam3CSK4 (PAM3) enhances sperm-oocyte interactions and improves cleavage and blastocyst rates; however, the underlying molecular mechanisms remain unexplored.

In this study, frozen-thawed active sperm from three high-fertility Holstein bulls were allocated to control or PAM3-treated groups before IVF. Both sperm and the resulting day 7 blastocysts were subjected to RNA sequencing (RNA-seq) to investigate whether TLR2/1 activation modulates the paternal RNA cargo and if these alterations persist in the embryonic transcriptome. PAM3 treatment significantly improved developmental outcomes, specifically cleavage and blastocyst rates, although the magnitude of the effect varied among bulls.