GSE182908
Knockdown of YBX1 impairs alternative splicing and maternal mRNA decay during pre-implantation development
In mammals, maternal gene products decay and zygotic genome activation (ZGA) onsets during maternal to zygotic transition (MZT). Y-box binding protein YBX1 plays vital roles in RNA stabilization and transcriptional regulation, but its roles in pre-implantation development remain to be elucidated. In the present study, we aim to investigate the role of YBX1 during goat MZT and further explore the molecular mechanisms. The expression of YBX1 was increased during MZT in goat, bovine, human, and mice. We successfully knocked down YBX1 by microinjection of siRNA against YBX1, and the embryo development was impaired when YBX1 was knocked down. Using RNA-seq, we identified 1623 up-regulated and 3531 down-regulated genes in the 8-cell stage YBX1 knockdown embryos. GO/KEGG/GSEA enrichment analysis revealed that the down-regulated genes were enriched in regulation of RNA/mRNA stability and spliceosome, suggesting that YBX1 might medicate pre-implantation development by alternative splicing and maternal mRNA decay. To this end, we identified 3284 differential alternative splicing events and 1322 differentially expressed maternal mRNAs at the 8-cell stage YBX1 knockdown embryos compared to the controls. Moreover, the splicing factors and mRNA decay related genes were aberrantly expressed. Lastly, knockdown of YBX1 impaired transcriptional activity during ZGA in goat and mice as revealed by 5-EU staining. Our results identify that YBX1 serves an important role in maternal mRNA decay, alternative splicing, and the transcriptional activity required for early embryogenesis, which will broaden the current understanding of YBX1 functions during the stochastic reprogramming events. Overall design: In this study, the 8-cell stage YBX1 knockdown embryos and the controls was directly lysed for RNA-seq and immunofluorescence staining. Bioinformatic analysis was performed to identified differentially expressed genes and alternative splicing events.