The ankyrin repeat-containing protein MdANK2B regulates salt tolerance and ABA sensitivity in Malus domestica.

Affiliation

Zhang FJ(1), Xie YH(1), Jiang H(2), Wang X(1), Hao YJ(1), Zhang Z(3), You CX(4).
Author information:
(1)National Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, National Research Center for Apple Engineering and Technology, Shandong Agricultural University, Tai-An, 271018, Shandong, China.
(2)State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yang ling, Shanxi, 712100, China.
(3)National Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, National Research Center for Apple Engineering and Technology, Shandong Agricultural University, Tai-An, 271018, Shandong, China. [Email]
(4)National Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, National Research Center for Apple Engineering and Technology, Shandong Agricultural University, Tai-An, 271018, Shandong, China. [Email]

Abstract

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