Faculty Opinions recommendation of ABO3, a WRKY transcription factor, mediates plant responses to abscisic acid and drought tolerance in Arabidopsis.

Being master regulators of gene expression, transcription factors (TFs) play important roles in determining plant growth, development and reproduction. To date, many TFs have been shown to positively mediate plant responses to environmental stresses. In the current study, the biological functions of a stress-responsive NAC [NAM (No Apical Meristem), ATAF1/2 (Arabidopsis Transcription Activation Factor1/2), CUC2 (Cup-shaped Cotyledon2)]-TF encoding gene isolated from soybean (GmNAC019) in relation to plant drought tolerance and abscisic acid (ABA) responses were investigated. By using a heterologous transgenic system, we revealed that transgenic Arabidopsis plants constitutively expressing the GmNAC019 gene exhibited higher survival rates in a soil-drying assay, which was associated with lower water loss rate in detached leaves, lower cellular hydrogen peroxide content and stronger antioxidant defense under water-stressed conditions. Additionally, the exogenous treatment of transgenic plants with ABA showed their hypersensitivity to this phytohormone, exhibiting lower rates of seed germination and green cotyledons. Taken together, these findings demonstrated that GmNAC019 functions as a positive regulator of ABA-mediated plant response to drought, and thus, it has potential utility for improving plant tolerance through molecular biotechnology.

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The Copper Responsive Transcription Factor SPL7 Represses Key Abscisic Acid Biosynthetic Genes to Balance Growth and Drought Tolerance

10.1101/2021.06.03.446925 ◽

2021 ◽

Author(s):

Lei Li ◽

Yanzhi Yang ◽

Jianmei Du ◽

Yihan Tao ◽

Chen Hao ◽

...

Keyword(s):

Transcription Factor ◽

Abscisic Acid ◽

Drought Tolerance ◽

Stress Responses ◽

De Novo ◽

Balance Growth ◽

Arabidopsis Seedling ◽

High Copper ◽

Squamosa Promoter Binding Protein ◽

Genes Encoding

Plants adapt to adverse environments by turning on defense against abiotic stresses, which is mainly orchestrated by the phytohormone abscisic acid (ABA). But how ABA homeostasis is modulated to balance growth and stress responses is still largely unknown. Here we report that prior treatment of Arabidopsis seedling with high copper retardates growth but enhances draught tolerance at later stages by modulating ABA accumulation. Subsequent genetic, physiological, transcriptomic, and molecular investigations revealed that the copper responsive transcription factor SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 7 (SPL7) is a strong regulator of ABA accumulation. We showed that SPL7 is destabilized by high copper and consistently suppresses genes encoding three key oxygenases in the ABA biosynthetic pathway of land plants via binding to the GTAC copper response motifs in their promoters. These results revealed a new mechanism whereby copper availability, inversely reflected by SPL7 abundance, modulates de novo ABA biosynthesis to balance growth and drought tolerance.

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Overexpressing the WRKY transcription factor OsWRKY97 improves drought tolerance in rice

10.21203/rs.3.rs-17373/v1 ◽

2020 ◽

Author(s):

Miaomiao lv ◽

Dejia Hou ◽

Taozhi Ye ◽

Lin Zhang ◽

Jiangbo Fan ◽

...

Keyword(s):

Transcription Factor ◽

Drought Stress ◽

Drought Tolerance ◽

Wrky Transcription Factor ◽

Wild Type ◽

Stress Protection ◽

Oxygen Scavenging ◽

Enzyme Superoxide Dismutase ◽

Reduced Water ◽

Higher Sensitivity

Abstract Background: WRKY transcription factor (TF) is one of the largest TF families in plants and plays an important role in plant development and stress protection. However, the function of individual WRKY gene in plants are still under investigation. Here, we identified a new member of WRKY TF family, OsWRKY97 , and analyze its role in stress resistance by using a series of transgenic plant lines.Results: OsWRKY97 , which positively regulates drought tolerance in rice. OsWRKY97 was expressed in all examined tissues and could be induced by various abiotic stresses. OsWRKY97 is located in the nucleus. Compared with the wild-type (WT), OsWRKY97 -overexpressing (OE) plants enhanced the tolerance of rice to drought and osmotic stress. In addition, OE plants also showed higher sensitivity to exogenous abscisic acid (ABA). When exposed to drought stress, up-regulation OsWRKY97 increased the accumulation of ABA and reduced water loss. Furthermore, OE plants achieved higher proline content and reduced levels of malondialdehyde (MDA) and reactive oxygen species (ROS). The homeostasis of ROS was maintained via the activity of active oxygen scavenging enzyme, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), activated by OsWRKY97Conclusions: These results indicate that OsWRKY97 plays a crucial role in the response to drought stress and may possess high potential value in improving drought tolerance in rice.

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