Changing the period of the somite segmentation clock

周期性体块分割由循环基因Hes7控制，Hes7的振荡表达依赖于具有延迟时间的负反馈。在这里，我们发现减少Hes7基因内的内含子数量缩短了延迟，导致Hes7振荡和体块分割的速度更快，增加了颈椎和上胸椎区域的体块和椎骨的数量。这些结果表明，内含子的数量对分割时钟的适当节奏很重要。

Periodic somite segmentation is controlled by the cyclic gene Hes7 whose oscillatory expression depends upon negative feedback with a delayed timing. Here, we show that reducing the number of introns within the Hes7 gene shortens the delay and results in a more rapid tempo of both Hes7 oscillation and somite segmentation, increasing the number of somites and vertebrae in the cervical and upper thoracic region. These results suggest that the number of introns is important for the appropriate tempo of the segmentation clock.