ABSTRACT

In this study, annual Magnolia denudata seedlings were treated with a 200 mmol L⁻¹ NaCl solution. Na⁺ content in its stems increased by more than about 24 times after 72 h and K⁺ content in leaves basically maintained in a steady state. MdeSOS1, isolated from M. denudata, comprised a 3453-bp ORF and included 12 transmembrane structures within its N terminal and a hydrophilic tail in its C-terminal. Its protein shared the identity of 68.3% and 62.7% at the peptide level with the homologue PeSOS1 and AtSOS1 respectively. The MdeSOS1 was significantly induced to up-regulation in various tissues exposed to salt stress and improved the salt tolerance of Arabidopsis. Our results also revealed that the MdeSOS1-GFP fusion protein was located on the plasma membrane and MdeSOS1 encoded a salt-inducible plasma membrane Na⁺/H⁺ antiporter, which provides a reference to improve the salt tolerance of Magnolia species by transgenic approaches.

摘要

在这项研究中，用200 mmol L ^-1 NaCl溶液处理一年生的厚朴木兰。72小时后，茎中的Na ⁺含量增加了约24倍以上，叶片中的K ⁺含量基本保持稳定。MdeSOS1，分离自M.苞，由3453-bp的ORF和包括在它的N末端12层跨膜结构和在其C末端的亲水性尾部。其蛋白质在肽水平上分别与同系物PeSOS1和AtSOS1的同一性为68.3％和62.7％。该MdeSOS1在暴露于盐胁迫的各种组织中，Aβ1被显着诱导上调并提高了拟南芥的盐耐受性。我们的研究结果还表明，MdeSOS1-GFP融合蛋白位于质膜上，MdeSOS1编码一种盐诱导性质膜Na ⁺ / H ⁺反转运蛋白，为通过转基因方法提高木兰的耐盐性提供了参考。