盐胁迫是影响植物生长、导致产量和品质下降的主要非生物逆境。项目组前期对耐盐醋栗番茄TS-21开展转录组测序，鉴定到两个受盐胁迫诱导明显的钠钙转运蛋白SlNCL2.2和SlNCL12。结合MIFE和生理生化方法解析TS-21的耐盐机制，可能是位于液泡膜的SlNCL2.2和SlNCL12激活钙信号和促进Na+区隔化在液泡中，从而增强TS-21的耐盐性。本项目拟在此研究基础上，创建超表达和敲除材料，进行耐盐性鉴定，明确其在番茄盐胁迫中的作用；利用酵母功能回补和TEVC方法研究其离子转运特异性；采用荧光染色成像技术研究其在液泡区隔化中的作用；结合转录组测序研究其对钙信号的影响，综合生化、电生理以及分子生物学实验阐明其生物学功能和作用机理。研究结果有利于揭示钠钙转运蛋白在植物盐胁迫中的作用机制，丰富植物抗逆理论，同时有助于创建耐盐新材料和培育耐盐新品种，具有重要的理论意义和实用价值。

Salinity is a major abiotic stress that seriously affects plant growth and productivity. In our previous research, two sodium-calcium exchangers (encoding gene SlNCL2.2 and SlNCL12), which significantly induced by salt stress, were identified by using RNA-seq analysis on tomato accession of Solanum pimpinellifolium TS-21. Associated with ionic homeostasis via MIFE technique, and the performance of physiological and biochemical tests, these tonoplast-located SlNCL2.2 and SlNCL12 may stimulate calcium signaling and facilitate Na+ compartmentation in TS-21, which finally enhances the salt tolerance. Based on the above findings, this project aims to (1) constructe SlNCL2.2 and SlNCL12 overexpression and knockout materials ,and understand their roles in salinity stress tolerance using biochemical, electro-physiological (MIFE) and molecular experiments; (2) identify ion transport specificity by yeast functional complementation test and TEVC (two electrode voltage-clamp) techniques; (3) investigate their roles in Na+ compartmentalization using fluorescence staining via confocal microscopy; and (4) investigate their roles in calcium signaling pathway via transcriptome sequencing. The results will enrich our knowledge about plant salinity stress tolerance, and benefit our effort in revealing the mechanism of sodium-calcium exchangers in plants in response to salt stress and creating salt tolerant germplasm, which is of great theoretical and practical significance.