拟南芥KEA1与KEA2对钾离子的响应及在外源糖应答中的分子机理研究

钾离子作为植物重要的营养元素，在维持叶绿体渗透平衡以及光合作用过程中是必需的；钾离子的缺乏会抑制光合作用与蛋白质合成，从而破坏氮和糖的平衡。而光合作用的产物糖对植物的生长发育以及抗逆境具有重要的作用。拟南芥K+/H+反向转运体KEA1与KEA2能够影响叶绿体结构、光合作用和生长发育，因此，AtKEA1与AtKEA2可能间接参与糖的代谢。目前，对植物KEA基因家族的生物功能研究非常有限，对植物钾离子转运体与糖作用的分子机理也鲜有报道。本研究将采用生物化学，分子生物学和细胞生物学等技术方法，分析在不同钾离子浓度条件下AtKEA1与AtKEA2的功能，及其在外源糖应答中分子机制，研究植物离子转运体与糖信号网的交联，为提高植物光合作用与钾离子利用效率，以及抵御缺钾等逆境的作用机制提供新的参考依据。

Potassium(K+) is one of the important nutritional elements, and it is essential to maintain osmotic balance of chloroplast and conduct photosynthesis; K+ starvation leads to impaired nitrogen and sugar balance due to inhibition of protein synthesis and photosynthesis. Sugar is the end product of photosynthesis, and it plays an important role in aspects of plant growth and development and resistance to adversity. K+/H+ antiporters KEA1 and KEA2 have critical function in struture of chloroplast, photosynthesis, and plant growth and development in Arabidopsis. Therefore, AtKEA1 and AtKEA2 may indirectly participate in sugar metabolism. Currently, Only few papers on biological functions of plant KEA gene families has been published, and there is very few research on the molecular mechanisms of plant K+ transporter and sugar signaling. In this study, we plan to identify biological functions and molecular mechanism of response to different levels of potassium and exogenous sugars of KEA1 and KEA2, and underlying cross-talk of plant K+ transporter and sugar signaling using biochemistry, molecular genetic and cell biological methods and techniques. The result provide new reference in plant response to abiotic stress and to improve the efficiency of photosynthesis and potassium utilization in plants，and provide a new idea in crop production.