An apple (Malus domestica) NAC transcription factor enhances drought tolerance in transgenic apple plants
An apple (Malus domestica) NAC transcription factor enhances drought tolerance in transgenic apple plants
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DOI：
10.1016/j.plaphy.2019.04.011
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发表时间：
2019-06-01
影响因子：
6.5
通讯作者：
Ma, Fengwang
中科院分区：
文献类型：
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作者：
Jia, Dongfeng;Jiang, Qi;Ma, Fengwang
植物NAC蛋白是最大的转录因子家族之一。它们在对各种非生物胁迫的反应中起着关键作用。然而，NAC蛋白在包括驯化苹果在内的多年生木本植物中非生物胁迫耐受中的作用及其机制尚未得到充分研究。在本研究中，我们鉴定了苹果MdNAC1转录因子在干旱胁迫响应中的作用。过表达MdNAC1基因的苹果植株对干旱胁迫的耐受性增强，表现在干旱条件下叶片水分流失和电解质泄漏减少，光合作用和光合色素含量保持不变。此外，在干旱条件下，转基因苹果株系的丙二醛（MDA）和活性氧（ROS）水平显著低于非转基因苹果株系。同时，转基因植株中超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）等几种抗氧化酶活性升高，相关基因表达量增加。总之，我们的研究结果表明，苹果MdNAC1基因的过表达通过促进更高的光合作用和活性氧清除酶的活性来增强苹果植株对干旱胁迫的耐受性。
Plant NAC proteins constitute one of the largest transcription factor families. They play pivotal functions during responses to various abiotic stresses. However, knowledge on roles of NAC proteins in abiotic stress tolerance as well as corresponding mechanisms has not been fully studied in perennial woody plants, including domesticated apple (Mains domestica). In the present study, we characterized the role of apple MdNAC1 transcription factor in response to drought stress. Apple plants overexpressing MdNAC1 gene exhibited promoted tolerance to drought stress, as evident by reduced water loss and electrolyte leakage in leaves, and maintenance of photosynthesis and photosynthetic pigments content under drought conditions. In addition, the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) were significantly lower for transgenic apple lines than those for non-transgenic plants under drought conditions. This was accompanied by higher activities of several antioxidant enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), as well as increased expression of the associated genes in transgenic lines. Together, our results indicate that overexpression of the apple MdNAC1 gene enhances drought stress tolerance in apple plants by promoting higher photosynthesis and activities of ROS-scavenging enzymes.