Awazu Satoko, Sasaki Akane, Matsuoka Terumi, Satoh Nori, Sasakura Yasunori
Department of Zoology, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Dev Biol. 2004 Nov 15;275(2):459-72. doi: 10.1016/j.ydbio.2004.08.029.
The enhancer trap technique, established in Drosophila melanogaster, is a very sophisticated tool. Despite its usefulness, however, there have been very few reports on enhancer traps in other animals. The ascidian Ciona intestinalis, a splendid experimental system for developmental biology, provides good material for developmental genetics. Recently, germline transgenesis of C. intestinalis has been achieved using the Tc1/mariner superfamily transposon Minos. During the course of that study, one Minos insertion line that showed a different GFP expression pattern from other lines was isolated. One fascinating possibility is that an enhancer trap event occurred in this line. Here we show that a Minos insertion in the Ci-Musashi gene was responsible for the altered GFP expression. Ci-Musashi showed a similar expression pattern to GFP. In addition, introns of Ci-Musashi have enhancer activity that can alter the expression pattern of nearby genes to resemble that of GFP in this line. These results clearly demonstrate that an enhancer trap event that entrapped enhancers of Ci-Musashi occurred in C. intestinalis.
在黑腹果蝇中建立的增强子陷阱技术是一种非常精密的工具。然而，尽管它很有用，但关于其他动物中增强子陷阱的报道却很少。海鞘（Ciona intestinalis）是发育生物学中一个出色的实验系统，为发育遗传学提供了良好的材料。最近，利用Tc1/水手超家族转座子Minos实现了海鞘的种系转基因。在该研究过程中，分离出了一个与其他品系表现出不同绿色荧光蛋白（GFP）表达模式的Minos插入品系。一种有趣的可能性是，在这个品系中发生了增强子陷阱事件。在这里，我们表明Ci-Musashi基因中的一个Minos插入导致了GFP表达的改变。Ci-Musashi表现出与GFP相似的表达模式。此外，Ci-Musashi的内含子具有增强子活性，能够改变附近基因的表达模式，使其类似于该品系中GFP的表达模式。这些结果清楚地表明，在海鞘中发生了捕获Ci-Musashi增强子的增强子陷阱事件。
