WRKY10 and ABF1/2 bind to VQ8 to form an accelerator-brake module for the regulation of dark- and ABA-induced leaf senescence in rice
Sique Chen,
Xianfeng Yang,
Hongrui Cao,
Baolin Huang,
Xiujuan Zheng,
Wenjia Xie,
Kangjing Liang,
Xinli Sun
Affiliations
Sique Chen
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China; Key Laboratory of Crop Breeding in South Zhejiang, Key Laboratory of Wenzhou Endemic Crop Biotechnology Innovation, Wenzhou Vocational College of Science & Technology/Wenzhou Academy of Agricultural Sciences, Wenzhou 325006, Zhejiang, China
Xianfeng Yang
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China
Hongrui Cao
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China
Baolin Huang
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China
Xiujuan Zheng
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China
Wenjia Xie
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China
Kangjing Liang
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China
Xinli Sun
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China; Corresponding author.
Transcription factors (TFs) play key roles in the regulatory network of leaf senescence. However, many nodes in this network remain unclear. To elucidate the mechanism of leaf senescence mediated by a rice TF, WRKY10, the expression of multiple senescence-related genes and physiological phenotypes were monitored in WRKY10- and VQ MOTIF-CONTAINING PROTEIN8 (VQ8)-overexpressing plants and the wrky10 and vq8 mutants. Our results showed that WRKY10 positively regulates abscisic acid (ABA)- and dark-induced senescence (DIS) by directly regulating the expression of multiple senescence-related genes. The VQ8 protein, a repressor of WRKY10, negatively regulates WRKY10-mediated DIS. The WRKY10-VQ8 module fine-tunes the progression of DIS. ABA, methyl jasmonate, and H2O2 accelerate WRKY10-mediated DIS, whereas ammonium nitrate and dithiothreitol delay WRKY10-mediated DIS. Further analysis revealed that WRKY10 and VQ8 interact with ABA RESPONSIVE ELEMENT BINDING FACTOR1 (ABF1) or ABF2. VQ8 represses the transcriptional activity of ABF1 and ABF2. Overexpression of ABF1 or ABF2 accelerates ABA- and dark-induced senescence and H2O2 accumulation in N. benthamiana leaves, and WRKY10 and VQ8 can inhibit either ABF1- or ABF2-induced cell necrosis. Taken together, WRKY10 integrates multiple senescence signals to establish an orderly progression of leaf senescence. The VQ8 protein acts as a brake on WRKY10-induced senescence and ABF1/2-induced cell death, preventing uncontrolled cell death.
