Department of Biology and Institute for Genome Sciences and Policy Center for Systems Biology, Duke University, Durham, NC 27708, USA.
Science. 2010 Sep 10;329(5997):1306-11. doi: 10.1126/science.1191937.
Plants and animals produce modular developmental units in a periodic fashion. In plants, lateral roots form as repeating units along the root primary axis; however, the developmental mechanism regulating this process is unknown. We found that cyclic expression pulses of a reporter gene mark the position of future lateral roots by establishing prebranch sites and that prebranch site production and root bending are periodic. Microarray and promoter-luciferase studies revealed two sets of genes oscillating in opposite phases at the root tip. Genetic studies show that some oscillating transcriptional regulators are required for periodicity in one or both developmental processes. This molecular mechanism has characteristics that resemble molecular clock-driven activities in animal species.
动植物以周期性的方式产生模块化的发育单位。在植物中，侧根沿着主根轴形成重复单位；然而，调节这个过程的发育机制尚不清楚。我们发现报告基因的循环表达脉冲通过建立前分支位点来标记未来侧根的位置，并且前分支位点的产生和根的弯曲是周期性的。微阵列和启动子-荧光素酶研究揭示了在根尖处呈相反相位振荡的两组基因。遗传研究表明，一些振荡的转录调控因子是一个或两个发育过程周期性所必需的。这种分子机制具有类似于动物物种中分子钟驱动活动的特征。
