AUTHOR=Liu Xiaomin , Jin Yibo , Tan Kexin , Zheng Jiangzhu , Gao Tengteng , Zhang Zhijun , Zhao Yongjuan , Ma Fengwang , Li Chao 

TITLE=MdTyDc Overexpression Improves Alkalinity Tolerance in Malus domestica

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.625890

DOI=10.3389/fpls.2021.625890

ISSN=1664-462X

ABSTRACT=Dopamine has been reported to be involved in plant growth, development and resistance to abiotic stresses. In our study, it was found that the expression of MdTyDc (Tyrosine decarboxylase gene) was induced by alkaline stress. Therefore, the apple plants overexpressing MdTyDc was treated with alkali stress, and we found that MdTyDc played an important role in apple plants’ resistance to alkali stress. Our results showed that the restriction on the growth, the decrease of membrane permeability and the accumulation of Na+ were alleviated to various degrees in MdTyDc transgenic plants under alkali stress. In addition, overexpression of MdTyDc enhanced the root activity and photosynthetic capacity, and improved the enzyme activity related to N metabolism, thus promoting N absorption. It is noteworthy that the dopamine content of these three transgenic lines is significantly higher than that of WT lines. In summary, these findings indicated that MdTyDc may enhance alkaline tolerance of apples by mediating dopamine content, mainly by maintaining high photosynthetic capacity, normal ion homeostasis and strong nitrogen absorption capacity.