Shoot Na+ Exclusion and Increased Salinity Tolerance Engineered by Cell Type-Specific Alteration of Na+ Transport in Arabidopsis
Shoot Na+ Exclusion and Increased Salinity Tolerance Engineered by Cell Type-Specific Alteration of Na+ Transport in Arabidopsis
复制标题
DOI：
10.1105/tpc.108.064568
复制
发表时间：
2009-07-01
期刊：
影响因子：
11.6
通讯作者：
Tester, Mark
中科院分区：
文献类型：
--
作者：
Moller, Inge S.;Gilliham, Matthew;Tester, Mark
土壤盐碱化影响大面积耕地，导致全球农作物产量大幅下降。许多作物的Na+毒害与地上部Na+的过量积累有关。我们以前曾建议，工程Na+排除从拍摄可以实现通过改变质膜Na+运输过程中的根，如果这些改变是细胞类型特异性的。在这里，它表明，表达的Na+转运蛋白HKT 1;1在拟南芥的成熟根中柱减少Na+的积累在地上部的37至64%。HKT 1的表达; 1特异性地在成熟根中柱中的表达是使用增强子陷阱表达系统特异性和强过表达来实现的。在地上部的效果是由增加的流入，介导的HKT 1;1，Na+进入中柱根细胞，这是证明在植物中，并导致根到地上部的Na+转移减少。植株地上部Na+含量降低，耐盐性也提高。相比之下，由花椰菜花叶病毒35 S启动子驱动的组成型表达HKT 1;1的植物积累了高的芽Na+，生长不良。我们的研究结果表明，在特定的细胞类型的特定Na+运输过程的修改可以减少地上Na+积累，许多高等植物耐盐性的重要组成部分。
Soil salinity affects large areas of cultivated land, causing significant reductions in crop yield globally. The Na+ toxicity of many crop plants is correlated with overaccumulation of Na+ in the shoot. We have previously suggested that the engineering of Na+ exclusion from the shoot could be achieved through an alteration of plasma membrane Na+ transport processes in the root, if these alterations were cell type specific. Here, it is shown that expression of the Na+ transporter HKT1;1 in the mature root stele of Arabidopsis thaliana decreases Na+ accumulation in the shoot by 37 to 64%. The expression of HKT1;1 specifically in the mature root stele is achieved using an enhancer trap expression system for specific and strong overexpression. The effect in the shoot is caused by the increased influx, mediated by HKT1;1, of Na+ into stelar root cells, which is demonstrated in planta and leads to a reduction of root-to-shoot transfer of Na+. Plants with reduced shoot Na+ also have increased salinity tolerance. By contrast, plants constitutively expressing HKT1;1 driven by the cauliflower mosaic virus 35S promoter accumulated high shoot Na+ and grew poorly. Our results demonstrate that the modification of a specific Na+ transport process in specific cell types can reduce shoot Na+ accumulation, an important component of salinity tolerance of many higher plants.