Over-expression of DREB46 enhances drought tolerance in Populus trichocarpa

Liangzhuang Geng; Jing Ren; Xiaolong Ji; Shaopeng Yan; Xing Shun Song

doi:10.1016/j.jplph.2023.153923

Over-expression of DREB46 enhances drought tolerance in Populus trichocarpa

J Plant Physiol. 2023 Feb:281:153923. doi: 10.1016/j.jplph.2023.153923. Epub 2023 Jan 14.

Authors

Liangzhuang Geng¹, Jing Ren², Xiaolong Ji¹, Shaopeng Yan³, Xing Shun Song⁴

Affiliations

¹ Department of Genetics, College of Life Science, Northeast Forestry University, Harbin, 150040, China.
² College of Food Science, Northeast Agricultural University, Harbin, 150030, China.
³ State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, 150040, China; Department of Genetics, College of Life Science, Northeast Forestry University, Harbin, 150040, China.
⁴ State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, 150040, China; Department of Genetics, College of Life Science, Northeast Forestry University, Harbin, 150040, China. Electronic address: xssong@nefu.edu.cn.

PMID: 36657232
DOI: 10.1016/j.jplph.2023.153923

Abstract

The drought responsive element binding (DREB) gene family has a significant role in plant abiotic stress responses. Here, we cloned a drought-inducible DREB gene, DREB46 (Potri.019G075500), and investigated its function in drought tolerance in Populus trichocarpa. Under treatment with exogenous abscisic acid and 6% PEG6000, DREB46 was rapidly and abundantly expressed. We successfully inserted P. trichocarpa DREB46 constructs into P. trichocarpa. After 11 d of drought stress and 3 d of rehydration treatment, the DREB46 over-expression (OE) lines exhibited significantly increased survival rates relative to the wild type (WT). Histochemical staining showed that the accumulation of reactive oxygen species (ROS) in transgenic plants under drought stress was lower than that in WT plants. Furthermore, OE plants displayed higher superoxide dismutase, peroxidase, and catalase activities and proline content, but lower malondialdehyde content than the WT plants under drought stress. In contrast, DREB46-RNA interference (RNAi) lines exhibited the opposite phenotype. Under PEG-6000 stress, OE plants produced significantly more adventitious roots (ARs) than WT plants. In contrast, RNAi-mediated DREB46-inhibited poplar exhibited fewer ARs. Quantitative real-time PCR indicated that WOX11/12a (Potri.013G066900), a gene related to root growth and development regulation, was significantly increased in OE plants. Additionally, yeast two-hybrid (Y2H) assays showed that DREB46 could interact with protein kinase MPK1 (Potri.002G032100) and protein phosphatase PP2C47 (Potri.007G058700), respectively, and this result was also verified by luciferase complementation assay. Transient co-expression results of leaves showed that PP2C47 and DREB46 Agrobacterium-transformed leaves had strong drought tolerance. These results show that DREB46 plays a key role in drought tolerance by inducing the ROS scavenging system and increasing the number of ARs.

Keywords: Adventitious root; DREB46 gene; Drought tolerance; Over expressed; Populus trichocarpa.

MeSH terms

Drought Resistance*
Droughts
Gene Expression Regulation, Plant
Plant Proteins / genetics
Plant Proteins / metabolism
Plants, Genetically Modified / genetics
Plants, Genetically Modified / metabolism
Populus* / genetics
Populus* / metabolism
Reactive Oxygen Species / metabolism
Stress, Physiological / genetics

Substances

Reactive Oxygen Species
Plant Proteins