Zygotic genome activation (ZGA) marks the transition of early embryos from maternal control to embryonic development programs. Yet, how ZGA timing is controlled remains elusive. Here, we created hybrid embryos from diverse mammalian species to address this question. These hybrids can develop up to the 8-cell stage, in which major ZGA occurs in a “first come first serve” manner. Both parental genomes are activated simultaneously, with significant transcription of transposons and housekeeping genes. Through comparative analysis of mouse gene activation in various hybrid contexts, we identified a deeply conserved Eif-like family proteins required for ZGA, influencing a large portion of ZGA genes and acting as nuclear licensing factors for zygotic genome activation. A detailed mechanistic investigation will be presented.

 

東京大学大学院理学系研究科・生物科学専攻・塩見研究室