AcWRKY40 mediates ethylene biosynthesis during postharvest ripening in kiwifruit

Zengyu Gan; Xin Yuan; Nan Shan; Chunpeng Wan; Chuying Chen; Yunhe Xu; Qin Xu; Jinyin Chen

doi:10.1016/j.plantsci.2021.110948

AcWRKY40 mediates ethylene biosynthesis during postharvest ripening in kiwifruit

Plant Sci. 2021 Aug:309:110948. doi: 10.1016/j.plantsci.2021.110948. Epub 2021 May 21.

Authors

Zengyu Gan¹, Xin Yuan², Nan Shan², Chunpeng Wan², Chuying Chen², Yunhe Xu², Qin Xu³, Jinyin Chen⁴

Affiliations

¹ Jiangxi Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Jiangxi Agricultural University, Nanchang, 330045, China; Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China.
² Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China.
³ Agriculture and Rural Bureau of Gongcheng Yao Autonomous County, Guilin, 542500, China.
⁴ Jiangxi Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Jiangxi Agricultural University, Nanchang, 330045, China; Jiangxi Key Laboratory for Postharvest Technology and Nondestructive Testing of Fruits and Vegetables, Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables, Jiangxi Agricultural University, Nanchang, 330045, China; College of Materials and Chemical Engineering, Pingxiang University, Pingxiang, 330075, China. Electronic address: jinyinchen@126.com.

PMID: 34134847
DOI: 10.1016/j.plantsci.2021.110948

Abstract

WRKY transcription factors belong to a superfamily that is involved in many important biological processes, including plant development and senescence. However, little is known about the transcriptional regulation mechanisms of WRKY genes involved in kiwifruit postharvest ripening. Here, we isolated a WRKY gene from the kiwifruit genome and named it AcWRKY40. AcWRKY40 is a nucleus-localized protein that possesses transcriptional activation activity. The expression of AcWRKY40 was detected, and the gene responded to ethylene treatment during kiwifruit postharvest ripening, indicating its involvement in this process at the transcriptional level. We found multiple cis-acting elements related to maturation and senescence in the AcWRKY40 promoter. GUS activity analysis showed that its promoter activity was induced by exogenous ethylene. Yeast one-hybrid and dual-luciferase assays demonstrated that AcWRKY40 binds to the promoters of AcSAM2, AcACS1, and AcACS2 to activate them. In addition, transient transformations showed that AcWRKY40 enhances the expression of AcSAM2, AcACS1, and AcACS2. Taken together, these results suggest that AcWRKY40 is involved in kiwifruit postharvest ripening, possibly by regulating the expression of genes related to ethylene biosynthesis, thus deepening our understanding of the regulatory mechanisms of WRKY transcription factors in fruit ripening.

Keywords: AcWRKY40; Ethylene biosynthesis; Gene expression; Kiwifruit; Postharvest ripening.

MeSH terms

Actinidia / genetics*
Actinidia / metabolism
Ethylenes / metabolism*
Fruit / genetics
Gene Expression Regulation, Plant*
Plant Proteins / genetics
Plant Proteins / metabolism*
Transcription Factors / genetics
Transcription Factors / metabolism
Transcriptome*

Substances

Ethylenes
Plant Proteins
Transcription Factors