Advances in Maternal-zygotic Transition
Jing Chen, Yu-Feng Wang*, Hao-Bin Zhao (College of Life Science, Central China Normal University, Wuhan 430079, China)
Maternal-zygotic transition (MZT), or mid-blastula transition (MBT) in some animals, has been observed in a variety of animal species. MZT is a complex phenomenon characterized by the initiation of transcrip- tion in the embryo and the replacement of maternal mRNA by embryonic mRNA and by the losing of synchronicity of cell division. These events are important for the embryos to transit to the late development stages. The molecular nature of the initiating MZT is largely unclear. It has been showed that MZT was affected by the nucleocytoplasmic ratio, cyclins and cyclin-dependent kinases, DNA replication/damage checkpoints, changes of DNA structure as well as the degradation of maternal factors and the transcription of some zygotic genes. The present paper reviews the features of MZT and the main factors involved in the initiation of MZT.