DDX3X regulates cell survival and cell cycle during mouse early embryonic development

• Published in: Journal of biomedical research Vol. 28; no. 4; pp. 282 - 291
• Main Authors: Li, Qian, Zhang, Pan, Zhang, Chao, Wang, Ying, Wan, Ru, Yang, Ye, Guo, Xuejiang, Huo, Ran, Lin, Min, Zhou, Zuomin, Sha, Jiahao
• Format: Journal Article
• Language: English
• Published: China Editorial Department of Journal of Biomedical Research 01.01.2014
• Subjects: 2-细胞胚胎; RNA解旋酶; siRNA; 小鼠; 早期胚胎发育; 细胞周期停滞; 细胞存活; 胚胎发育过程; apoptosis; DDX3X; cell cycle; early embryo; p53
• ISSN: 1674-8301
• DOI: 10.7555/JBR.27.20130047

DDX3X is a highly conserved DEAD-box RNA helicase that participates in RNA transcription, RNA splicing, and mRNA transport, translation, and nucleo-cytoplasmic transport. It is highly expressed in metaphase II （MII） oocytes and is the predominant DDX3 variant in the ovary and embryo. However, whether it is important in mouse early embryo development remains unknown. In this study, we investigated the function of DDX3X in early embryogenesis by cytoplasmic microinjection with its siRNA in zygotes or single blastomeres of 2-cell embryos. Our results showed that knockdown of Ddx3x in zygote cytoplasm led to dramatically diminished blastocyst formarion, reduced cell numbers, and an increase in the number of apoptotic cells in blastocysts. Meanwhile, there was an accumulation of p53 in RNAi blastocysts. In addition, the ratio of cell cycle arrest during 2-cell to 4-cell transition increased following microinjection of Ddx3x siRNA into single blastomeres of 2-cell embryos compared with control. These results suggest that Ddx3x is an essential gene associated with cell survival and cell cycle control in mouse early embryos, and thus plays key roles in normal embryo development.