CmWRKY6-1-CmWRKY15-like transcriptional cascade negatively regulates the resistance to fusarium oxysporum infection in Chrysanthemum morifolium

Weihao Miao; Xiangyu Xiao; Yuean Wang; Lijiao Ge; Yanrong Yang; Ye Liu; Yuan Liao; Zhiyong Guan; Sumei Chen; Weimin Fang; Fadi Chen; Shuang Zhao

doi:10.1093/hr/uhad101

CmWRKY6-1-CmWRKY15-like transcriptional cascade negatively regulates the resistance to fusarium oxysporum infection in Chrysanthemum morifolium

Hortic Res. 2023 May 10;10(7):uhad101. doi: 10.1093/hr/uhad101. eCollection 2023 Jul.

Authors

Weihao Miao^{1

2

3}, Xiangyu Xiao^{1

2

3}, Yuean Wang^{1

2

3}, Lijiao Ge^{1

2

3}, Yanrong Yang^{1

2

3}, Ye Liu^{1

2

3}, Yuan Liao^{1

2

3}, Zhiyong Guan^{1

2

3}, Sumei Chen^{1

2

3}, Weimin Fang^{1

2

3}, Fadi Chen^{1

2

3}, Shuang Zhao^{1

2

3}

Affiliations

¹ College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
² Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China.
³ Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, Jiangsu 210014, China.

Abstract

Chrysanthemum Fusarium wilt is a soil-borne disease that causes serious economic losses to the chrysanthemum industry. However, the molecular mechanism underlying the response of chrysanthemum WRKY to Fusarium oxysporum infection remains largely unknown. In this study, we isolated CmWRKY6-1 from chrysanthemum 'Jinba' and identified it as a transcriptional repressor localized in the nucleus via subcellular localization and transcriptional activation assays. We found that CmWRKY6-1 negatively regulated resistance to F. oxysporum and affected reactive oxygen species (ROS) and salicylic acid (SA) pathways using transgenic experiments and transcriptomic analysis. Moreover, CmWRKY6-1 bound to the W-box element on the CmWRKY15-like promoter and inhibited its expression. Additionally, we observed that CmWRKY15-like silencing in chrysanthemum reduced its resistance to F. oxysporum via transgenic experiments. In conclusion, we revealed the mechanism underlying the CmWRKY6-1-CmWRKY15-like cascade response to F. oxysporum infection in chrysanthemum and demonstrated that CmWRKY6-1 and CmWRKY15-like regulates the immune system.