水稻缺铁信号与茉莉酸信号互作的分子机制

项目名称： 水稻缺铁信号与茉莉酸信号互作的分子机制

项目编号： No.31470347

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 郑录庆

作者单位： 南京农业大学

项目金额： 85万元

中文摘要： 铁是植物生长必需的微量元素，过量时对植物产生毒害。植物进化出一套机制控制体内铁的动态平衡应对环境的变化，这对于生长在淹水与干旱交替变化的水田自然环境下的水稻极为重要。但是，人们对于水稻中铁的动态平衡的调控机制仍不清楚。我们分析水稻转录组结果时发现，茉莉酸（JA）合成及信号途径基因受缺铁强烈诱导，而缺铁响应基因的表达却受JA处理强烈抑制，显示JA信号负调控缺铁响应基因的表达。此外，JA途径关键基因OsMYC2L的突变体显示缺铁超敏感表型。上述结果表明JA可能作为信号分子参与调控水稻铁的动态平衡。为阐明水稻缺铁与JA信号间的互作关系，我们将分析铁信号缺陷型遗传材料（铁关键转录因子敲除或干涉植株）中JA相关基因的表达、信号转导、生理反应，以及JA信号缺陷型遗传材料对缺铁的生理及分子生物学反应，克隆介导缺铁与JA信号的关键互作功能基因，从分子水平解析JA与缺铁信号的互作机制。

中文关键词： 水稻；耐缺铁响应；转录调控；信号互作

英文摘要： Iron (Fe) is an essential micronutrient for plant growth and development, while becomes toxic at high concentration. Therefore, plant has a system to strictly regulate Fe homeostasis in response to environmental changes. This is especially important for rice because Fe in paddy soil changes greatly between flooded and unflooded conditions through the whole growth period. However, the molecular mechanisms underlying Fe hemostasis are poorly understood. Our preliminary experiment with microarray showed that the expression of many jasmonate (JA) related genes including key genes for JA biosynthesis and JA signaling pathway, were significantly up-regulated by Fe conditions. Furthermore, the expression of genes involved in Fe-deficiency responses was significantly repressed after exposure to JA. In addition, the mutant of JA pathway gene OsMYC2L showed more sensitive to Fe deficiency treatment. These results suggest that JA may function as a signal to sense the changes of Fe availability. The object of this study is to investigate the the cross-talk between Fe-deficiency and JA signaling in rice. We will use both physiological and molecular approaches to examine how JA affects the expression of genes involved in Fe uptake, translocation and distribution. For this purpose, we will use knockout or knockdown lines of JA-related genes to compare the plant response to changing Fe concentrations. This work will help us better understanding of how plants overcome environmental Fe changes through JA signaling.

英文关键词： Rice;Fe deficiency response;transcriptional regulation;signal cross-talk