FvWRKY50 is an important gene that regulates both vegetative growth and reproductive growth in strawberry

Abstract

The WRKY transcription factors play important roles in plant growth and resistance, but only a few members have been identified in strawberry. Here we identified a WRKY transcription factor, FvWRKY50, in diploid strawberry which played essential roles in strawberry vegetative growth, and reproductive growth. Knocking out FvWRKY50 by genome editing accelerated flowering time and leaf senescence but delayed anthocyanin accumulation in fruit. Further analysis showed that FvWRKY50 acted as a transcriptional repressor to negatively regulate the expression of flowering- and leaf senescence-related genes, including FvFT2, FvCO, FvFT3, and FvSAUR36. Notably, FvWRKY50 directly upregulated the expression of FvCHI and FvDFR by binding their promoter under normal conditions, but at low temperature FvWRKY50 was phosphorylated by FvMAPK3 and then induced protein degradation by ubiquitination, delaying anthocyanin accumulation. In addition, the homozygous mutant of FvWRKY50 was smaller while the biallelic mutant showed normal size. These new findings provide important clues for us to further reveal the regulatory mechanisms of strawberry growth and fruit ripening.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (32222074, 32072551), the National Key Research and Development Program of China (2022YFD2100102-3), 111 Project (B17043), Beijing Innovation Consortium of Agriculture Research System (BAIC04-2022), and the 2115 Talent Development Program of China Agricultural University.

Author contributions

B. L. designed the study. Y. C. carried out the majority of the experiments and analyzed the data. L. L., Q. F., C. L., Y. B., N. Z., R. S., Z. Y. assisted to do some experiments. C. Z. and Y. W. provided advice and support for the study. B. L and Q. L. wrote the manuscript. All authors read and approved the manuscript.

Data availability

Data supporting the results reported in the paper are available in the main text and supplementary data.

Conflict of interest

None declared.

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