Tracing the dynamic changes in the lncRNA-mediated competing endogenous RNA network during bovine preimplantation embryo development

Long noncoding RNAs (lncRNAs) can regulate gene expression by "sponging" microRNAs (miRNAs), reducing their inhibitory effects on mRNAs. However, this mechanism has been minimally investigated in preimplantation embryo development. In this study, we revisited existing RNA sequencing and small RNA sequencing data to investigate the role of lncRNAs in in vitro-produced bovine preimplantation embryos. Our findings revealed that although lncRNAs exhibit expression patterns similar to mRNAs, maternal lncRNAs degrade earlier than mRNAs during embryonic genome activation (EGA). Weighted gene co-expression network analysis identified 27 modules of mRNA and lncRNA, with enrichment analysis showing a significant negative correlation between the polycomb repressive complex pathway and blastocyst formation (R² = -0.98). Additionally, bioinformatics analysis was used to predict and construct lncRNA-miRNA-mRNA networks, highlighting that lncRNAs bind more to miRNAs compared with mRNAs. Moreover, lncRNA-induced lncRNA-miRNA-mRNA axes participated in mRNA degradation and biogenesis around the EGA stage. These interactions became stronger after EGA, especially after the 16-cell stage. Overall, our study provides new insights into lncRNA-mediated regulatory networks during bovine preimplantation development.