Overexpression of MzASMT 1, a Gene From Malus zumi Mats, Enhances Salt Tolerance in Transgenic Tobacco

Frontiers in Plant Science

卷:11

Tianyu Liu¹  Shenchun Qu¹  Hongxue Wang¹  Weibing Zhuang²  Xiaochun Shu²  Zhong Wang²  Tao Wang²  Fengjiao Zhang² 

[1] College of Horticulture, Nanjing Agricultural University, Nanjing, China;

[2] Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden, Memorial Sun Yat-sen), Nanjing, China;

关键词: melatonin;    MzASMT 1;    salt tolerance;    ROS;    antioxidant enzyme system;   

DOI  :  10.3389/fpls.2020.561903

来源: DOAJ

【 摘 要 】

Melatonin, widely found in various plants as a new antioxidant, could protect plants from various biotic and/or abiotic stresses, including salt stress. MzASMT 1 (KJ123721), a gene from Malus zumi Mats, is a key enzyme required for melatonin synthesis. However, whether the overexpression of MzASMT 1 could regulate the synthesis of melatonin and improve the salt tolerance in tobacco remains unknown. In this study, the overexpression of MzASMT 1 in tobacco increased the melatonin content, and the transgenic lines owned higher salt tolerance capacity. The transgenic lines overexpressing MzASMT 1 exhibited lower degree of leaf wilting; much more fresh weight; higher plant height; longer root; higher relative water content (RWC) of leaves, stem, and root; and higher chlorophyll content and Fv/Fm, which makes transgenic lines better adapt to salt stress. The transgenic lines also had higher accumulation of proline, lower accumulation of malondialdehyde (MDA), and improved antioxidant systems, which protected plants from cell damage and oxidative stress due to excess reactive oxygen species (ROS) accumulation under salt treatment. The transcription of salt response genes was much more highly activated in transgenic lines than in wild type under salt stress. The above results contributed to the understanding of functions for MzASMT 1 in tobacco under salt stress and provided a new choice for the application of MzASMT 1 in improving plant salt tolerance.

【 授权许可】

Unknown