The WRKY Transcription Factor GmWRKY12 Confers Drought and Salt Tolerance in Soybean.

Wen-Yan Shi,Long-Guo Jin,Dong-Hong Min,Jian Ma,Yong-Bin Zhou,Ming Chen,Jun Chen,Xiao-Hong Zhang,You-Zhi Ma,Zhao-Shi Xu,Yong-Tao Du

doi:10.3390/ijms19124087

Abstract

WRKYs are important regulators in plant development and stress responses. However, knowledge of this superfamily in soybean is limited. In this study, we characterized the drought- and salt-induced gene GmWRKY12 based on RNA-Seq and qRT-PCR. GmWRKY12, which is 714 bp in length, encoded 237 amino acids and grouped into WRKY II. The promoter region of GmWRKY12 included ABER4, MYB, MYC, GT-1, W-box and DPBF cis-elements, which possibly participate in abscisic acid (ABA), drought and salt stress responses. GmWRKY12 was minimally expressed in different tissues under normal conditions but highly expressed under drought and salt treatments. As a nucleus protein, GmWRKY12 was responsive to drought, salt, ABA and salicylic acid (SA) stresses. Using a transgenic hairy root assay, we further characterized the roles of GmWRKY12 in abiotic stress tolerance. Compared with control (Williams 82), overexpression of GmWRKY12 enhanced drought and salt tolerance, increased proline (Pro) content and decreased malondialdehyde (MDA) content under drought and salt treatment in transgenic soybean seedlings. These results may provide a basis to understand the functions of GmWRKY12 in abiotic stress responses in soybean.

Highlights

Drought and salinity are the most important abiotic stress factors affecting plants growth and crop yield
The GmWRKYs are distributed in different tissues or located upstream of soybean genes to bind the W-box consensus (TTGACY) in the promoters of target genes, initiating functions such as plant development, pathogen defense, insect resistance, response to biotic and abiotic stress and participating in signal transduction mediated by plant hormones [59,60]
In this study, using RNA-Seq, we identified 62 GmWRKY genes in the soybean genome that were differently expressed in six different tissues under normal condition

Summary

Introduction

Drought and salinity are the most important abiotic stress factors affecting plants growth and crop yield. 1/3 of cultivable land suffers drought and salinization, which is equivalent to a loss of about 1,500,000 ha of crop land per year [1]. The damage caused by drought and salt are almost the sum of losses caused by other stress factors. Under limited land and water resources, it is necessary to breed new stress-resistant varieties to increase yield and ensure food security. Cultivation of stress-resistant crop varieties is an important way to ensure high and stable yield of crops. Transgenic technology has become an important way to learn the function of genes in crops [2,3,4]

Methods

Results

Discussion

Conclusion