Transcription factor OsWRKY72 is involved in Cu/Cd toxicity by regulating lignin synthesis in rice
Xiangchao Shangguan,
Zhonghe Tian,
Yu Wang,
Tengwei Xiao,
Xiaoyu Yu,
Wen Jing,
Kejian Peng,
Zhenguo Shen,
Zhubing Hu,
Yan Xia
Affiliations
Xiangchao Shangguan
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Zhonghe Tian
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Yu Wang
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Tengwei Xiao
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Xiaoyu Yu
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Wen Jing
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Kejian Peng
Hunan Research Academy of Environmental Sciences, Changsha 410128, Hunan, China
Zhenguo Shen
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China; Corresponding authors.
Zhubing Hu
State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, College of Agriculture, Henan University, Kaifeng 475004, Henan, China; Corresponding authors.
Yan Xia
College of Life Sciences, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China; Corresponding authors.
Maintenance of ion homeostasis in plant cells is an essential physiological requirement for sustainable growth, development, and yield of crops. Plants respond to high levels of heavy metals such as copper (Cu) and cadmium (Cd) to avoid irreversible damage at the structural, physiological and molecular levels. Our previous study found that rice germin-like proteins (OsGLPs) are a type of Cu-responsive proteins. The deletion of 10 tandem OsGLP genes on chromosome 8 led to more severe heavy metal toxicity in rice. In this study, we show that rice WRKY transcription factor OsWRKY72 negatively regulates OsGLP8-7 transcription. Overexpression of OsWRKY72 weakens the Cu/Cd tolerance of rice when exposed to Cu and Cd. OsWRKY72 suppressed expression of OsGLP8-7 and lignin synthesis genes, resulting in reduced lignin polymerization and consequently lower lignin accumulation in cell walls, thereby increasing the Cu and Cd accumulation. In addition, OsWRKY53 bound to OsWRKY72 to alleviate the transcriptional inhibition of OsGLP8-7. These results revealed that OsWRKY72-OsGLP8-7 is an important module response of rice to heavy metal stress, and that transcription factor OsWRKY72 acts upstream of OsGLP8-7 to regulate Cu/Cd toxicity.
