Cis-regulatory code for determining the action of Foxd as both an activator and a repressor in ascidian embryos
Cis-regulatory code for determining the action of Foxd as both an activator and a repressor in ascidian embryos
复制标题
用于确定 Foxd 在海鞘胚胎中作为激活剂和阻遏剂的作用的顺式调控代码
DOI：
10.1016/j.ydbio.2021.03.010
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发表时间：
2021
影响因子：
2.7
通讯作者：
Satou Yutaka
中科院分区：
文献类型：
--
作者：
Tokuhiro Shinichi;Satou Yutaka
在无脊椎脊索动物ciona的早期胚胎中，动物-植物轴是由母体因素的组合作用建立的。这些母体因子的一个靶点Foxd在植物半球中特异性表达，通过激活植物半球特异性基因和抑制动物半球特异性基因来稳定动物-植物轴。这种双重功能对早期海鞘胚胎的胚胎发生至关重要；然而，Foxd作为抑制因子和激活因子的机制尚不清楚。在这里，我们在flhx3 /4的上游找到了一个Foxd结合位点，该位点被Foxd激活，并将其与dmrt .a上游的Foxd抑制结合位点进行了比较。我们发现激活位点以低亲和力结合Foxd，而抑制位点以高亲和力结合Foxd。报告分析证实，激活和抑制Foxd结合位点之间的这种定性差异足以改变Foxd的功能。因此，我们得出结论，Foxd转录调控的结果是由切入调控元件编码的。
In early embryos ofCiona, an invertebrate chordate, the animal-vegetal axis is established by the combinatorial actions of maternal factors. One target of these maternal factors,Foxd, is specifically expressed in the vegetal hemisphere and stabilizes the animal-vegetal axis by activating vegetal hemisphere-specific genes and repressing animal hemisphere-specific genes. This dual functionality is essential for the embryogenesis of early ascidian embryos; however, the mechanism by which Foxd can act as both a repressor and an activator is unknown. Here, we identify a Foxd binding site upstream ofLhx3/4, which is activated by Foxd, and compare it with a repressive Foxd binding site upstream ofDmrt.a. We found that activating sites bind Foxd with low affinity while repressive sites bind Foxd with high affinity. Reporter assays confirm that this qualitative difference between activating and repressive Foxd binding sites is sufficient to change Foxd functionality. We therefore conclude that the outcome of Foxd transcriptional regulation is encoded incis-regulatory elements.