Transcriptional regulation of aluminum and phosphate stres-responsive genes in plants

酸性土壤是全球农业生产的主要限制因素。限制植物在这些土壤上生长的因素包括铝（Al）毒性和磷酸盐（Pi）缺乏。因此，植物适应酸性土壤需要的机制，赋予耐铝和机制，以提高磷的收购。基因表达实验的初步分析（拟南芥中Al胁迫和油菜中Pi胁迫的转录组谱分析）已经鉴定了一系列响应于两种胁迫的基因（共表达，可能共调节）。一个引人注目的观察结果是，铝和磷胁迫诱导的基因编码的许多酶参与碳代谢（糖酵解）的表达变化。一个有趣的可能性是，通过糖酵解的碳流量的增加，需要提供应力特异性代谢产物不仅为耐铝和磷胁迫，但也为其他非生物胁迫需要大量的碳资源分配。为了深入了解植物对铝和磷胁迫的反应，我们必须确定和阐明这些胁迫反应中涉及的调控网络。拟议研究的目标是使用当前的遗传，分子和计算工具来识别拟南芥中Al和Pi胁迫反应系统的调控成分，并提供对这些途径的调控及其共享关系的见解。为了鉴定调控网络的组成部分，我们将使用两种互补的技术来检测DNA结合蛋白（例如转录因子）和它们所结合的DNA序列（例如顺式调控元件）之间的相互作用。从这项研究中获得的知识将有助于我们开发更能耐受酸性土壤的作物品种的长期目标。

Acid soils are a major limitation to agricultural production worldwide. Factors that limit plant growth on these soils include aluminum (Al) toxicity and phosphate (Pi) deficiency. As a result, plant adaptation to acid soils requires mechanisms that confer tolerance to Al and mechanisms to enhance Pi acquisition. Preliminary analysis of gene expression experiments (transcriptome profiling of Al stress in Arabidopsis and Pi stress in canola) has identified an array of genes responsive to both stresses (co-expressed, potentially co-regulated). One striking observation was that both Al and Pi stress induced changes in expression of genes coding for many enzymes involved in carbon metabolism (glycolysis). An intriguing possibility is that increases in carbon flow through glycolysis are required to supply stress-specific metabolites not only for resistance to Al and Pi stress, but also for other abiotic stresses requiring a large allocation of carbon resources. To gain insight into plant responses to Al and Pi stress, we must identify and characterise the regulatory network(s) involved in these stress responses. The goal of the proposed research is to use current genetic, molecular, and computational tools to identify regulatory components of the Al and Pi stress response system(s) in Arabidopsis, and provide insight into the regulation of these pathways and the relationships they share. To identify components of the regulatory network(s), we will use two complementary techniques that detect interactions between DNA-binding proteins (e.g. transcription factors) and the DNA sequences to which they bind (e.g. cis-regulatory elements). The knowledge gained from this research will aid our long term goal of developing crop species better able to tolerate acid soils.