EIF4E1B interacts with HSPA1A and PPP2CA and is involved in mouse oocyte maturation and early embryonic development

The protein translation process is an important part of mammalian ovogenesis and early embryonic development. The eukaryotic translation initiation factors 4E family (eIF4E) initiates the eukaryotic mRNA translation process and plays an important role in protein synthesis. The aim of this research was to analyze the expression and localization of eIF4E family members and the role of EIF4E1B in mouse oocyte maturation and early embryonic development. Here, we report the expression and localization of EIF4E1, EIF4E2, and EIF4E3 in multiple tissues, during oocyte maturation and early embryonic development in mice. However, EIF4E1B was expressed only in ovarian and testicular tissues, and this protein was detected only at the one-to two-cell embryonic stage of early embryos. Moreover, knockdown of eIF4E1b in GV-stage oocytes and zygotes resulted in significant reductions in the rates of oocyte maturation and blastocyst formation, respectively. Further investigation revealed that EIF4E1B interacted with the PPP2CA and HSPA1A proteins and might be involved in the mouse oocyte maturation process. These results provide the first evidence for a novel function of EIF4E1B in oocyte maturation and early embryonic development in mice.