Key message

The ankyrin repeat-containing protein MdANK2B was identified to contribute to increasing resistance to salt stress and decreasing sensitivity to ABA in Malus domestica.

Abstract

Ankyrin (ANK) repeat-containing proteins occur widely in prokaryotes, eukaryotes, and even in some viruses and play a critical role in plant growth and development, as well as the response to biotic and abiotic stress. However, the function of ANK repeat-containing proteins in apple (Malus domestica) has not yet been investigated. Here, we identified apple MdANK2B based on homology analysis with the Arabidopsis ANK repeat-containing proteins AtAKR2A and AtAKR2B. MdANK2B was found to be localized in the cytoplasm, and its encoding gene was highly expressed in both apple leaves and fruits. In addition, MdANK2B gene expression was highly induced by salt stresses and abscisic acid (ABA). Overexpression of MdANK2B increased resistance to salt stress and decreased sensitivity to ABA in both transgenic apple calli and seedlings. In addition, overexpression of MdANK2B reduced the accumulation of reactive oxygen species (ROS) by enhancing the activity of antioxidant enzymes in response to salt stress. Our data revealed the role of MdANK2B in response to salt stress and ABA treatment in apple, which widens the known functions of ANK repeat-containing proteins in response to abiotic stress.

中文翻译：

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含锚蛋白重复蛋白 MdANK2B 调节苹果的耐盐性和 ABA 敏感性

关键信息

含有锚蛋白重复序列​​的蛋白质MdANK2B被鉴定为有助于提高对盐胁迫的抵抗力并降低对 ABA 的敏感性。

抽象的

锚蛋白 (ANK) 重复蛋白广泛存在于原核生物、真核生物甚至某些病毒中，在植物生长发育以及对生物和非生物胁迫的反应中发挥着关键作用。然而，苹果（Malus domestica）中含有 ANK 重复序列的蛋白质的功能尚未得到研究。在这里，我们基于与拟南芥 ANK 重复序列蛋白 AtAKR2A 和 AtAKR2B 的同源性分析鉴定了苹果 MdANK2B。MdANK2B定位于细胞质，其编码基因在苹果叶和果实中均高表达。此外，盐胁迫和脱落酸 (ABA) 高度诱导MdANK2B基因表达。MdANK2B的过表达转基因苹果愈伤组织和幼苗对盐胁迫的抵抗力增加，对 ABA 的敏感性降低。此外，MdANK2B的过表达通过增强抗氧化酶响应盐胁迫的活性来减少活性氧 (ROS) 的积累。我们的数据揭示了MdANK2B在苹果中响应盐胁迫和 ABA 处理的作用，这拓宽了含有 ANK 重复序列的蛋白质响应非生物胁迫的已知功能。