A 14-3-3 Protein-Encoding Gene, BdGF14g, Confers Better Drought Tolerance by Regulating ABA Biosynthesis and Signaling

Yang Zhang; Yuan He; Hongyan Zhao; Yan Zhang; Jing Yang; Xingqi Ou; Jinlong Zhang; Qidi Zhu

doi:10.3390/plants12233975

A 14-3-3 Protein-Encoding Gene, BdGF14g, Confers Better Drought Tolerance by Regulating ABA Biosynthesis and Signaling

Plants (Basel). 2023 Nov 26;12(23):3975. doi: 10.3390/plants12233975.

Authors

Yang Zhang^{1

2}, Yuan He², Hongyan Zhao², Yan Zhang³, Jing Yang³, Xingqi Ou¹, Jinlong Zhang¹, Qidi Zhu¹

Affiliations

¹ School of Agriculture, Henan Institute of Science and Technology, Xinxiang 453003, China.
² The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science & Technology, Wuhan 430074, China.
³ School of Life Sciences, Henan Institute of Science and Technology, Xinxiang 453003, China.

Abstract

Abscisic acid (ABA), a phytohormone, enacts a cardinal function in coping with abiotic stress. 14-3-3 proteins can interact with ABA-responsive-element-binding transcription factors (ABFs), a chief constituent of ABA signaling, and play critical roles in the dehydration response involving ABA signaling. Meanwhile, whether and how 14-3-3 proteins regulate ABA signaling to respond to aridity stress is yet to be fully investigated. Herein, BdGF14g, a 14-3-3 gene induced by ABA, H₂O₂, and PEG treatments, was identified in Brachypodium distachyon (B. distachyon). Overexpression of BdGF14g improved drought stress tolerance in tobacco plants, with a higher survival rate, longer root length, enhanced cell membrane stability, and increased antioxidase activity compared with non-transgenic controls in coping with dehydration. Both drought and exogenous ABA treatments resulted in smaller stomatal apertures in BdGF14g-transgenic lines. Additionally, when an ABA biosynthesis inhibitor was added, the better growth statuses, less H₂O₂ accumulation, and higher activities of catalase and superoxide dismutase under mannitol stress disappeared. Moreover, BdGF14g interacted with NtABF2, upregulated the endogenous ABA content, and enhanced the transcription of ABA-related genes, including NtNCED1, a crucial ABA biosynthesis gene, under drought conditions. In conclusion, BdGF14g acts as a positive factor in the water deficiency response by affecting ABA biosynthesis and signaling in tobacco plants.

Keywords: BdGF14g; ROS-scavenging system; abscisic acid; drought stress.

Grants and funding

This work was funded by the National Genetically Modified New Varieties of Major Projects of China (2016ZX08010004-004), the National Natural Science Foundation of China (grant numbers 31900240, 32001548, and 32372210), and the Key Scientific and Technological Research Project of Henan Province (grant no. 232102111093).