HKT1定位缺失突变体转化对受体酵母Na+耐受性影响的研究

通过重叠延伸PCR（overlop extension PCR)技术对来自小麦根系的高亲和力的K^ 运输载体HKT1的cDNA进行定位缺失突变，分析了HKT1及其缺失突变体L149－E180和E150－L166转化酵母对受体Na^ 耐受性的影响。结果表明，HKT1缺失区段越大其对酵母的转化频率越高，缺失突变降低了HKT1对Na^ 的亲和性，显著提高了受体对Na^ 的耐受性，且L149－E180突变体对Na^ 亲和性低于E150-L166,这表明L149－E180区段在HKT1中对Na^ 代谢起着重要作用。

Effect on the Na+ Tolerance of Yeast Transformed with Site Directed Deletion Mutants of HKT1

Site directed deficiency mutagenesis on cDNA of the wheat root with high affinity K + transporter HKT1 were carried by using overlop extension PCR.The effect on Na + tolerance of yeasts transformed with HKT1, deficiency mutant L149 E180 and E150 L166 were studied respectively. The results showed that transformation frequency increased with the increase of the deletion region length of HKT1.The deficiency mutation reduced Na + affinity of HKT1 and increased significantly Na + tolerance of yeast transformed, and the Na + affinity of L149 E180 deletion mutant was lower than that of E150 L166.The results of this mutational analysis suggest that L149 E180 domain in HKT1 plays an important role in the binding and transport of Na +.