【摘要】 为了探究马铃薯脯氨酸转运蛋白在逆境下的功能,以马铃薯GS393 (Solanum commersonii-LZ3.4-Wisconsin, United States)为试验材料,采用PCR的方法,克隆得到2个脯氨酸转运蛋白基因分别命名为stuProT1和stuProT2,它们的开放阅读框长度分别为504 bp和600 bp,分别编码189个和199个氨基酸。系统进化树分析结果表明,这2个蛋白和番茄ProT蛋白具有高度同源性。实时荧光定量PCR表明,stuProT1和stuProT2基因在GS393不同组织(根,茎,叶,匍匐茎和块茎)中均有表达,其中根和茎的表达量较高。q PCR分析这2个基因在不同激素、重金属、低温、干旱和盐胁迫下的表达情况。分析结果表明:ABA抑制stuProT1和stuProT2基因表达(36 h内);2个基因分别在GA3、IAA、6-BA处理的2 h、8 h、24 h出现诱导表达峰值。供试重金属都能诱导2个基因的表达,其中Al、Cd、Hg处理48 h内始终处于上调水平,不同处理诱导表达峰值出现时间不同;Cu处理下2 h时出现表达峰值,其他时间回调。stuProT1和stuProT2基因对PEG-6000处理十分敏感,处理时间内始终高水平表达。NaCl处理2～8 h内出现高水平表达,之后回调。4℃和-4℃处理下2个基因都表现为先下调后回升的特点。综合分析表明stuProT2比stuProT1在各种胁迫条件下的响应更强烈。本研究弄清了在非生物胁迫下,ProT是脯氨酸高度选择的运输的转运体。更多还原

【Abstract】 To identified the function of potato proline transporter under stress conditions, potato GS393(Solanum commersonii-LZ3.4-Wisconsin, United States) was used as the experimental material, and two proline transporter genes were cloned for stuProT1 and stuProT2 by PCR. stuProT1 open reading frame is 504 bp in length and encodes 189 amino acids; stuProT2 open reading frame is 600 bp in length and encodes 199 amino acids.Phylogenetic tree analysis showed that the two proteins and tomato ProT protein have high homology. Real-time PCR showed that stuProT1 and stuProT2 genes were expressed in different tissues(roots, stems, leaves, stolons and tubers) of GS393, and the expression of roots and stems was higher. The results of qPCR analysis for stuProT1 and stuProT2 genes under different hormones, heavy metals, low temperature, drought and salt stress, showed that:ABA inhibits expression of stuProT1 and stuProT2 gene(within 36 h). The absorption peaks of two genes were observed at 2 h, 8 h, and 24 h of GA3, IAA, 6-BA induced treatment. The heavy metals could induce the expression of stuProT1 and stuProT2 gene, among which Al, Cd and Hg were always in the up-regulated level within 48 h, and the peak of expression were distinct in different treatments. The peak of expression was observed at 2 h after Cu treatment, and the other time was below. The stuProT1 and stuProT2 genes are sensitive to PEG-6000 treatment and are always expressed at high levels. High levels of expression within 2～8 hours of NaCl treatment and callback followed. Both genes under the treatment of 4℃ and-4℃ showed the characteristics of down-regulation and then callback. Comprehensive analysis showed that stuProT2 responded more strongly than stuProT1 under various stress conditions. This study identified ProT as a highly selective transporter of proline under abiotic stress.更多还原