Conserved hierarchical gene regulatory networks for drought and cold stress response in Myrica rubra

Weijie Xu; Haiying Ren; Xingjiang Qi; Shuwen Zhang; Zheping Yu; Jianbo Xie

doi:10.3389/fpls.2023.1155504

Conserved hierarchical gene regulatory networks for drought and cold stress response in Myrica rubra

Front Plant Sci. 2023 Apr 14:14:1155504. doi: 10.3389/fpls.2023.1155504. eCollection 2023.

Authors

Weijie Xu^{1

2}, Haiying Ren^{1

3

4}, Xingjiang Qi^{1

3

4}, Shuwen Zhang^{1

3}, Zheping Yu^{1

3}, Jianbo Xie^{2

5}

Affiliations

¹ State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-Products, Institute of Horticulture, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
² State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China.
³ State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Hangzhou, China.
⁴ Xianghu Lab., Hangzhou, China.
⁵ The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, Beijing Forestry University, Beijing, China.

Abstract

Stress response in plant is regulated by a large number of genes co-operating in diverse networks that serve multiple adaptive process. To understand how gene regulatory networks (GRNs) modulating abiotic stress responses, we compare the GRNs underlying drought and cold stresses using samples collected at 4 or 6 h intervals within 48 h in Chinese bayberry (Myrica rubra). We detected 7,583 and 8,840 differentially expressed genes (DEGs) under drought and cold stress respectively, which might be responsive to environmental stresses. Drought- and cold-responsive GRNs, which have been built according to the timing of transcription under both abiotic stresses, have a conserved trans-regulator and a common regulatory network. In both GRNs, basic helix-loop-helix family transcription factor (bHLH) serve as central nodes. MrbHLHp10 transcripts exhibited continuous increase in the two abiotic stresses and acts upstream regulator of ASCORBATE PEROXIDASE (APX) gene. To examine the potential biological functions of MrbHLH10, we generated a transgenic Arabidopsis plant that constitutively overexpresses the MrbHLH10 gene. Compared to wild-type (WT) plants, overexpressing transgenic Arabidopsis plants maintained higher APX activity and biomass accumulation under drought and cold stress. Consistently, RNAi plants had elevated susceptibility to both stresses. Taken together, these results suggested that MrbHLH10 mitigates abiotic stresses through the modulation of ROS scavenging.

Keywords: Chinese bayberry; ROS scavenging; abiotic stress tolerance; bHLH transcription factor; gene regulatory networks.

Grants and funding

This study was supported by Breeding for Agricultural New Varieties in Zhejiang Province (2021C02066-2) and Key R&D Projects in Zhejiang Province (2019C02038, 2020C02001, and 2021C02009), State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products (2021DG700024-KF202306), the Key Laboratory of Horticultural Plant Genetic and Improvement of Jiangxi Province, the open project of the Key Laboratory of Horticultural Plant Genetic and Improvement of Jiangxi Province (2021KFJJ001), National Key R&D Program of China (No.2022YFD2201600; 2022YFD2200602), the Project of the National Natural Science Foundation of China (NOs., 32022057 and 31972954), Forestry and Grassland Science and Technology Innovation Youth Top Talent Project of China (No. 2020132607).