钙离子介导的植物低温感受分子机理研究

Cold temperature is detrimental to agricultural production and a longstanding question is how plants perceive cold. Cold triggers Ca2+ influx in plant cells , leading to a transient increase in [Ca2+]i . This is believed to be involved in cold sensing. However, the underlying molecular mechanisms are unknow. Our research group focuses on the study of Ca2+ channel-mediated plant abiotic stress for a long time. We have acquired sufficient resources and expertise to carry out the proposed experiments, expecially the establishment of high-throughput Arabidopsis mutant screening system based on aequorin and Ca2+ imaging. In the previous study, we have screened several mutant candidates with defective in cold-induced [Ca2+]i increases and isolated a calcium signal reduced gene (CSR1).In this project, we will try to explain the molecular mechanism on how plants perceiving cold through analyzing its function in cold sensing and cold tolerance in Arabidopsis.The project will potentially provide both basic and applied knowledge for us to improve crop adaptability to cold.

冷害是影响农作物生长发育的重要环境因子，而植物如何感受环境低温是人们长期关注而又亟待解决的问题。低温刺激促进细胞Ca2+的内流，引起细胞内游离钙离子浓度（[Ca2+]i）增加，但其内在分子机理研究甚少。申请者所在研究团队长期从事钙离子与植物抗逆相关的研究，积累了大量与本项目相关的技术和方法，尤其是基于水母发光蛋白和钙离子成像技术的高通量的突变体筛选体系的建立，以及一些相关基因的克隆，为本项目的顺利开展奠定了坚实的基础。运用已有的技术体系，本项目前期通过筛选低温诱导下 [Ca2+]i升高不显著的缺陷型T-DNA插入突变体，分离克隆到其中一个低温诱导下钙信号减弱的基因CSR1，拟通过对其表达模式、基因功能以及对低温诱导响应的专一性分析，进一步深入探讨目标基因在植物抗寒耐冻过程中的作用机理，为今后采用基因工程的方法提高农作物对低温的适应性奠定基础。

冷害是影响农作物生长发育的重要环境因子，而植物如何感受环境低温是人们长期关注而又亟待解决的问题。低温刺激促进细胞Ca2+的内流，引起细胞内游离钙离子浓度（[Ca2+]i）增加，但其内在分子机理研究甚少。结合前期研究基础，本项目运用转入水母发光蛋白基因的拟南芥转化株（WT-AQ）构建T-DNA插入的突变体库，在低温诱导下筛选[Ca2+]i升高不显著的突变体，克隆到一个低温感受相关的基因（CSR1），通过分析目标基因的表达模式、亚细胞定位、对低温刺激的特异性、在HEK293细胞中的钙信号变化以及突变体和超表达株系对极端温度响应的生理表型等，深入探讨目标基因在植物响应温度变化过程中的作用。