The Role of AtbZIP1 in Sugar Regulatory Network

细胞信号的调节可以发生在许多不同的水平上。其中一个信号机制是DNA元件和DNA结合转录因子（TFs）之间的相互作用，它可以作为一个调控回路来开启或关闭基因表达。尽管至少10%的拟南芥基因对糖有反应，但已知与糖信号有关的调控回路很少。利用微阵列分析，本研究者鉴定了184个拟南芥中葡萄糖反应性tf。其中45种tf似乎对葡萄糖有反应，而不需要新的蛋白质合成，即葡萄糖反应不能被蛋白质合成抑制剂环己亚胺（CHX）消除。假设糖反应性tf在糖信号传导中起关键作用，而chx不敏感tf调节chx敏感tf以创建一个相互连接的调节网络。为了验证这一假设，PI将使用chx不敏感和糖反应的bZIP转录因子作为模型。将进行反向遗传分析以揭示该bZIP在植物糖反应中的作用。bZIP的下游靶基因将通过染色质免疫沉淀偶联基因芯片分析（Chip - Chip）进行鉴定。这些研究还将使用计算和湿实验室分析来确定bZIP的上游调节因子。这项研究有望揭示糖对植物基因表达的全球调控作用。该项目还将为分子遗传学、生物化学、功能基因组学和生物信息学领域的本科生、研究生和博士后提供跨学科的培训机会。积累的微阵列数据和本建议的大部分产出将整合到公共存储所提供的基于网络的资源中。

Regulation of cell signaling can occur at many different levels. One such signaling mechanism is the interaction between DNA elements and DNA-binding transcription factors (TFs), which can act as a regulatory circuit to turn on or turn off gene expression. Despite the fact that at least 10% of all Arabidopsis genes are sugar responsive, very few regulatory circuits are known to be associated with sugar signaling. Using micro array analysis, this investigator has identified 184 glucose responsive TFs in Arabidopsis. Forty-five of these TFs appear to be glucose responsive without requiring new protein synthesis, i.e. the glucose response cannot be eliminated by the protein synthesis inhibitor cycloheximide (CHX). The hypothesis is that sugar-responsive TFs play key roles in sugar signaling and that CHX-insensitive TFs modulate CHX-sensitive TFs to create an inter-connected regulatory network. To test this hypothesis, the PI will use a CHX-insensitive and sugar-responsive bZIP transcription factor as a model. Reverse genetic analyses will be conducted to unravel the role of this bZIP in plants sugar responses. The downstream target genes of the bZIP will be identified by chromatin immunoprecipitation coupled Gene Chip analysis (ChIP-chip). These studies will also identify the upstream regulators of the bZIP using both computational and wet-lab analyses. This research is expected to shed light on the global regulatory roles of sugar on gene expression in plants. This project will also provide interdisciplinary training opportunities for undergraduates, graduates, and postdoctoral researchers in the area of molecular genetics, biochemistry, functional genomics, and bioinformatics. The accumulated micro array data and a large portion of the output from this proposal will be integrated into web-based resources available at public depositories.