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作 者 ：甘晓燕，石 磊，陈虞超，李 苗，宋玉霞 *

期 刊 ：西北植物学报 2012年 2期 页码：225~230

关键词：梭梭；NHX基因；基因克隆；

Keywords:Haloxylon ammodendron, Na+/H+ antiporter gene, gene cloning,

摘 要 ：采用RT-PCR、RACE方法从超旱生、耐盐植物梭梭中扩增出Na⁺/H⁺逆向转运蛋白基因的开放阅读框架，其核苷酸序列长1 683 bp,推测的氨基酸序列全长为560个氨基酸残基。含有多个物种Na⁺/H⁺逆向转运蛋白基因的高度保守序列氨氯砒嗪脒的结合位点(LFFIYLIPPI)。序列一致性分析结果显示，该cDNA片段与同科植物NHX基因的一致性为70%～80％，但与不同科植物的一致性较低，仅为60％，表明该基因在进化上存在多样性，但它们都具有氨氯砒嗪脒结合位点，对Na⁺具有高度专一性，对植物的耐盐性起着重要作用。

Abstract:Through RT-PCR (reverse transcription polymerase chain reaction) and RACE (rapid amplification of cDNA ends),a 1 683 bp fragment containing entire Na⁺/H⁺ antiporter coding region of 560 amino acids (aa) has been obtained from extreme xerophyte and salt-tolerant plant Haloxylon ammodendron.The amino acid sequence contains a high conservative sequence-binding domain of amiloride (LFFIYLLPPI).The nucleotide sequence of HaNHX cDNA shared 70%~80% identity with that in the same families,and 60% identity with those of other families.This analysis suggested that the HaNHX genes are evolutionarily diversified although they all have a binding domain of amiloride and a high specificity on Na⁺ which is of great importance in salt tolerance.

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