Abe Yoko, Chen Wei, Huang Wei, Nishino Mizuho, Li Yi-Ping
Department of Cytokine Biology, The Forsyth Institute, Boston, MA 02115, USA.
Dev Biol. 2006 Jul 1;295(1):116-27. doi: 10.1016/j.ydbio.2006.03.012. Epub 2006 Apr 19.
We recently demonstrated that Cellular Nucleic acid Binding Protein (CNBP)(-/-) mouse embryos exhibit forebrain truncation due to a lack of proper morphogenetic movements of the anterior visceral endoderm (AVE) during pre-gastrulation stage (Chen, W., Liang, Y., Deng, W., Shimizu, K., Ashique, A.M., Li, E., Li, Y.P., 2003. The zinc-finger protein CNBP is required for forebrain formation in the mouse, Development 130, 1367-1379). However, CNBP expression pattern in the mouse forebrain suggests that CNBP may have more direct effects during forebrain development. Our data show that CNBP is expressed in tissues of early chick embryo that are the equivalent to the mouse embryo. Using a combination of RNAi-silencing and Retrovirus-misexpression approaches, we investigated the temporal function of CNBP in the specification/development of the chick forebrain during organogenesis. The silencing of CNBP expression resulted in forebrain truncation and the absence of BF-1, Six3 and Hesx1 expression, but not Otx2 in chick embryos. Misexpression of CNBP induced the expression of BF-1, Six3 and Hesx1 in the hindbrain, but not the expression of Otx2. These results offer novel insights into the function of CNBP during organogenesis as the regulator of forebrain formation and a number of rostral head transcription factors. Moreover, CNBP and Otx2 may play roles as regulators of forebrain formation in two parallel pathways. These new insights into CNBP functions underscore the essential role of CNBP in forebrain formation during chick embryo organogenesis.
我们最近证明，细胞核酸结合蛋白（CNBP）基因敲除（-/-）小鼠胚胎在前原肠胚形成阶段由于前内脏内胚层（AVE）缺乏适当的形态发生运动而出现前脑截断（Chen, W., Liang, Y., Deng, W., Shimizu, K., Ashique, A.M., Li, E., Li, Y.P., 2003. 锌指蛋白CNBP是小鼠前脑形成所必需的，《发育》130, 1367 - 1379）。然而，CNBP在小鼠前脑中的表达模式表明，CNBP在前脑发育过程中可能具有更直接的作用。我们的数据显示，CNBP在早期鸡胚与小鼠胚胎相对应的组织中表达。我们使用RNA干扰沉默和逆转录病毒错误表达方法相结合，研究了CNBP在鸡胚器官发生过程中前脑特化/发育的时间功能。CNBP表达的沉默导致鸡胚前脑截断以及BF - 1、Six3和Hesx1表达缺失，但Otx2表达未受影响。CNBP的错误表达在后脑中诱导了BF - 1、Six3和Hesx1的表达，但未诱导Otx2的表达。这些结果为CNBP在器官发生过程中作为前脑形成和一些头部前端转录因子的调节因子的功能提供了新的见解。此外，CNBP和Otx2可能在两条平行途径中作为前脑形成的调节因子发挥作用。这些对CNBP功能的新见解强调了CNBP在鸡胚器官发生过程中前脑形成中的重要作用。
