以拟南芥AtNHX1 cDNA 片段作为探针，筛查水稻盐胁迫植株叶片cDNA 文库，获得与AtNHX1同源的水稻新型液泡Na+/H+逆向转运蛋白基因（OsANT1）。序列分析表明，OsANT1 全长cDNA为2 178 bp，包括一个长度为1 608 bp的完整开放阅读框，编码535个氨基酸残基。在DNA水平上，OsANT1基因含有15个外显子和14个内含子，长度为4 835 bp。OsANT1含有12个跨膜域，系统进化树分析结果表明，与来自拟南芥、水稻、小麦、玉米、大麦、马蔺和芦苇等的Na+/H+逆向转运蛋白高度同源。盐胁迫条件下，OsANT1的表达具有盐分诱导特征，且随着胁迫的增大而增加。表明该基因可能在水稻抵御盐分胁迫的过程中具有一定作用。
Using a cDNA fragment PCR amplified from Arabidopsis AtNHX1 as the probe, a novel vacuole Na+/H+ antiporter gene (OsANT1) in rice was obtained based on the screening of a cDNA library made from leaves of rice plants treated with 200 mmol L-1 NaCl. The results indicated that the full-length of OsANT1 cDNA was 2 178 bp. The open reading frame (ORF) of OsANT1 was
1 608 bp with 535 translated amino acids. OsANT1 had 15 exons and 14 introns with a total length of 4 835 bp at the DNA level. It was found that OsANT1 contained 12 transmembrane domains and had high similarities with other vacuole Na+/H+ antiporters from plant species, such as Arabidopsis thaliana, Oryza sativa, Triticum aestivum, Zea mays, Hordeum vulgare, Iris lacteal, and Phragmites australis. The expression of OsANT1 in leaf, stem and root was all induced by NaCl and the expression levels were increased with the increase of NaCl concentration applied and the elongation of NaCl treatment time. Taken together, it is suggested that OsANT1 is functional for rice to withstand NaCl under salt stress.
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