导读：英国爱丁堡大学研究人员发现一种名为TOC1的蛋白质能阻止基因夜间活动，这种蛋白质先前被认定关联帮助植物苏醒，可引发植物夜间休眠并控制开花。
研究人员发现一种名为TOC1的蛋白质能阻止基因夜间活动，这种蛋白质先前被认定关联帮助植物苏醒。他们利用电脑模型，模拟水芹的12个基因如何共同设定植物的内部时钟。
安德鲁·米勒教授11日告诉英国广播公司（BBC）记者，“这是思维方式的一大转变”。
植物与人类一样都有生理节律，可帮助它们随着日夜变化和季节更替作出微小调整。“对植物而言，生物钟尤为重要，”米勒说，“那将帮助他们应对白天和夜晚，储存能量生长。”
米勒说，新数据将帮助研究人员发现更多其他植物基因，“我们现在知道大约12个基因，仍想了解那些控制光合作用、利用氮、打开花瓣和散发香味的基因”。同时，这一发现有助于研究其他植物，尤其是小麦、大麦和水稻等农作物。
研究报告刊登在英国《分子系统生物学》上。
The clock gene circuit in Arabidopsis includes a repressilator with additional feedback loops
Alexandra Pokhilko, Aurora Pi|[ntilde]|as Fern|[aacute]|ndez, Kieron D Edwards, Megan M Southern, Karen J Halliday, Andrew J Millar
Recent findings are incorporated into a new mathematical model of the plant circadian clock, revealing a complex circuit structure comprised of multiple negative feedback loops, and predicting a repressive role for a key regulator, TOC1, which the authors confirm experimentally. The feedback structure of the plant clock's evening loop was reconstructed based on multiple data, and is now represented by the evening complex (ELF3–ELF4–LUX), which represses transcription from the ELF4 and LUX promoters. Computational analysis of timeseries data from mutant plants predicts that TOC1 is a repressor of the key morning genes LHY and CCA1, not an activator. Analysis of LHY and CCA1 expression in TOC1 gain- and loss-of-function plants confirms this prediction. Light induction of LHY and CCA1 expression is predicted to determine the clock's response to brief light pulses, matching the observed phase-response curve. The evening complex controls LHY and CCA1 expression by a double-negative connection, rather than direct activation, forming part of a three-component repressilator circuit, which is itself only part of the more complex circuit of the clock system.
文献链接：https://www.nature.com/msb/journal/v8/n1/synopsis/msb20126.html
