背景回顾：Sugars are essential metabolites for energy and anabolism that can also act as signals to regulate plant physiology and development. Experimental tools to disrupt major sugar signalling pathways are limited. We have performed a chemical screen for modifiers of activation of circadian gene expression by sugars to discover pharmacological tools to investigate and manipulate plant sugar signalling. 

主要发现：Using a library of commercially available bioactive compounds, we identified 75 confident hits that modified the response of a circadian luciferase reporter to sucrose in dark-adapted Arabidopsis thaliana seedlings. 

结果1-进一步验证：We validated the transcriptional effect on a subset of the hits and measured their effects on a range of sugar-dependent phenotypes for 13 of these chemicals. 

结果2-糖信号转导途径：Chemicals were identified that appear to influence known and unknown sugar signalling pathways.  

结果3-糖激活的钙离子信号：Pentamidine isethionate (PI) was identified as a modifier of a sugar-activated Ca2+ signal that acts as a calmodulin inhibitor downstream of superoxide in a metabolic signalling pathway affecting circadian rhythms, primary metabolism and plant growth.

结论：Our data provide a resource of new experimental tools to manipulate plant sugar signalling and identify novel components of these pathways.

 摘 要 

糖是植物能量和合成代谢的必须代谢物，同时也可以作为信号物质，调控植物生理和发育。然后，目前仍没有很好的实验工具用于扰乱主要的糖信号转导途径。作者在之前的实验中通过化学方法筛选由糖激活生物钟基因表达的调节因子，发现了用于研究和调整植物糖信号转导的药理学工具。通过对商用的具有生物活性的化合物库，作者筛选到了75个化合物能够影响黑暗条件下拟南芥实生苗中生物钟LUC报告基因对于蔗糖的响应。作者进一步验证了其中一部分化合物对于报告基因转录活性的影响，并且测试了其中13个化合物对于一系列糖浓度依赖性表型的影响。作者发现这些化合物能够影响那些已知的糖信号转导途径，同时也能影响一些未知的糖信号转导途径。PI是一个作用于糖激活的钙离子信号调节因子，作为超氧化物下游的钙调素抑制剂影响生物节律，主要涉及代谢和植物生长。本文的研究结果为研究植物糖信号转导以及鉴定新的糖信号转导途径组分提供了新的实验工具。

 Michael J Haydon