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从大豆中克隆到了液泡膜Na~+/H~+反向转运蛋白编码基因(GmNHXI)的全长cDNA,包括5′端非翻译区464 bp,编码区1641 bp,3′端非翻译区486 bp,共2591 bp．该cDNA编码的GmNHX1蛋白共546个氨基酸,具有典型的液泡膜Na~+/H~+反向转运蛋白特征,与已知功能的液泡膜Na~+/H~+反向转运蛋白AtNHX1,OsNHX1及AgNHX1具有较高的同源性．GmNHX1在大豆基因组中为单拷贝基因,其表达具有组织特异性,并能受到NaCl,KCl,LiCl,ABA以及脱水等胁迫上调；耐盐品种GmNHX1的转录水平在叶片中低于而在根系和下胚轴中均高于敏盐品种．将GmNHX1 cDNA置于两个串联的CaMV35S启动子控制下在豆科模式植物百脉根中过表达,提高了转基因百脉根的耐盐性．Na~+及K~+含量测定表明,与对照相比,过表达GmNHX1的百脉根小苗中Na~+,K~+含量显著降低,K~+/Na~+比率显著增加,显示了百脉根中过表达GmNHX1所导致的耐盐性与减少转基因植物中Na~+的积累有密切关系．
The full-length cDNA of GmNHXI was cloned from soybean, including 464 bp 5 ’untranslated region, 1641 bp coding region, and 3’ untranslated region 486 bp, total 2591 bp. The GmNHX1 protein encoded by this cDNA has a total of 546 amino acids. It has typical characteristics of tonoplast Na ~ + / H ~ + antiporter and is related to the known function of tonoplast Na ~ + / H ~ + antiporter AtNHX1, OsNHX1 And AgNHX1 has high homology. GmNHX1 is a single copy gene in soybean genome. Its expression is tissue-specific and can be up-regulated by NaCl, KCl, LiCl, ABA and dehydration. The transcript level of GmNHX1 is lower in leaves than in roots and Hypocotyls were higher than sensitive salt varieties. The GmNHX1 cDNA was overexpressed in leguminous plants under control of two tandem CaMV35S promoters and increased salt tolerance of the transgenic Lotus corniculatus. The contents of Na ~ + and K ~ + were significantly decreased and the ratio of K ~ + / Na ~ + was significantly increased in the seedlings of GmNHX1 overexpressing GmNHX1 compared with the control Salt tolerance induced by overexpression of GmNHX1 in the veins is closely related to the reduction of Na ~ + accumulation in transgenic plants.