Cucumber glossy fruit 1 (CsGLF1) encodes the zinc finger protein 6 that regulates fruit glossiness by enhancing cuticular wax biosynthesis

Abstract

Cucumber glossiness is an important visual quality trait that affects consumer choice. Accumulating evidence suggests that glossy trait is associated with cuticular wax accumulation. However, the molecular genetic mechanism controlling cucumber glossiness remains largely unknown. Here, we report the map-based cloning and functional characterization of CsGLF1, a locus that determines the glossy trait in cucumber. CsGLF1 encodes a homolog of the Cys2His2-like fold group (C2H2)-type zinc finger protein 6 (ZFP6) and its deletion leads to glossier pericarp and decreased cuticular wax accumulation. Consistently, transcriptomic analysis demonstrated that a group of wax biosynthetic genes were downregulated when CsZFP6 was absent. Further, transient expression assay revealed that CsZFP6 acted as a transcription activator of cuticular wax biosynthetic genes. Taken together, our findings demonstrated a novel regulator of fruit glossiness, which will provide new insights into regulatory mechanism of fruit glossiness in cucumber.

Acknowledgements

This work was supported by grants from the National Natural Science Foundation of China (32272718), Jiangsu Key Research and Development Program (BE2022339), Jiangsu Agricultural Science and Technology Independent Innovation Fund Project (CX(20)3165), the Key Project For Jiangsu Agricultural New Variety Innovation (PZCZ201720), the Jiangsu Provincial Entrepreneurship and Innovation Doctor Program, the Yangzhou City’s Green and Golden Phoenix Program, Modern Agriculture Foundation of Yangzhou (YZ2020036), and the Promoting Project for Open Competition Mechanism to Select the Best Candidates of Jiangsu Seed Industry (JBGS[2021] 018).

Author contributions

X.C. and C.C. designed the study. Y.Y., C.C., Y.P.W., and Y.R.W. performed the research. C.C., Y.P.W., Y.R.W., and H.J. analysed the data. Y.Y., C.C., and X.C. wrote the manuscript. All authors read and approved the final manuscript.

Data availability statement

The raw sequence data of this study were deposited in the sequence read archive of the National Center for Biotechnology Information under accession number PRJNA808486.

Conflicts of interest

The authors declare no competing interests.

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