Natural variation in cytokinin maintenance improves salt tolerance in apple rootstocks
Natural variation in cytokinin maintenance improves salt tolerance in apple rootstocks
复制标题
细胞分裂素维持的自然变化提高了苹果砧木的耐盐性
DOI：
10.1111/pce.13403
复制
发表时间：
2019-02-01
影响因子：
7.3
通讯作者：
Han, Zhenhai
中科院分区：
文献类型：
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作者：
Feng, Yi;Liu, Jing;Han, Zhenhai
经历盐胁迫的植物通常在应激反应的早期阶段降低细胞分裂素水平。有趣的是，我们发现在盐胁迫下，苹果砧木“罗布斯塔”的细胞分裂素含量保持在较高水平。通过筛选参与细胞分裂素生物合成和分解代谢的基因，我们发现IPT5b在罗布斯塔根中的高表达水平与维持细胞分裂素的高含量有关。我们在IPT5b的启动子区域发现了一个42 bp的缺失，该缺失提高了IPT5b的表达水平，并且该缺失与robustaxM的耐盐性有关。9 .人口隔离。42 bp的缺失导致了脯氨酸响应元件（Proline Response Element, proore）的缺失，我们的研究结果表明proore在脯氨酸的作用下负调控IPT5b的表达。在盐胁迫下，由于proore基因缺失，脯氨酸无法抑制IPT5b的表达，使罗布斯塔品种的细胞分裂素水平保持在较高水平，从而提高了耐盐性。
Plants experiencing salt-induced stress often reduce cytokinin levels during the early phases of stress-response. Interestingly, we found that the cytokinin content in the apple rootstock "robusta" was maintained at a high level under salt stress. Through screening genes involved in cytokinin biosynthesis and catabolism, we found that the high expression levels of IPT5b in robusta roots were involved in maintaining the high cytokinin content. We identified a 42 bp deletion in the promoter region of IPT5b, which elevated IPT5b expression levels, and this deletion was linked to salt tolerance in robustaxM.9 segregating population. The 42 bp deletion resulted in the deletion of a Proline Response Element (ProRE), and our results suggest that ProRE negatively regulates IPT5b expression in response to proline. Under salt stress, the robusta cultivar maintains high cytokinin levels as IPT5b expression cannot be inhibited by proline due to the deletion of ProRE, leading to improve salt tolerance.