VvMYB44-VvERF045 complex is involved in abscisic acid-induced sugar accumulation by activating VvSPS4 expression in grapes

Abstract

Phytohormones play a crucial role in regulating fruit ripening and quality, particularly in soluble sugar accumulation. Despite this, the molecular mechanisms behind hormone-induced sugar accumulation in grapes are not well understood. Our study shows that abscisic acid (ABA) enhances grape berry ripening and soluble sugar levels. We generated a transcriptome dataset from grape berries subjected to hormone treatment and constructed a potential regulatory network related to sugar accumulation using weighted gene co-expression network analysis (WGCNA). Furthermore, we identified five structural genes (SGs) and 44 transcription factors (TFs) responsive to ABA that potentially regulate sugar accumulation in grape berries. Notably, VvMYB44 was emphasized due to its highest expression in ABA-treated mature fruits among these TFs. It binds to the promoter of VvSPS4 and activates its expression, thereby influencing sucrose metabolism. Additionally, VvERF045 interacts with VvMYB44, further amplifying its transcriptional activation of VvSPS4. Overexpressing VvERF045 also increased the soluble sugar levels in tomato fruits. These findings underscore the role of the VvMYB44-VvERF045 complex in sugar accumulation and provide new insights into the molecular mechanisms underlying sugar accumulation in grapes.

Acknowledgements

This research was funded by the Postdoctoral Fellowship Program of CPSF under Grant Number GZB20240439, the Ningbo Science and Technology Development Special Fund (2024S018), the Fujian Province Science and Technology Plan Project (2024S0051), China Agriculture Research System (CARS-29-zp-7), National Natural Science Foundation of China (32102346), and Key Research and Development Program of Shaanxi Province (2023-ZDLNY-28).

Author contributions

B.L., S.J., S.W., and L.W. conceived and designed the experiments; B.L., J.L., M.Z., and performed the experiments with assistance from Z.W. and Z.Y.; B.L., and M.Z. analyzed the data; B.L. wrote the manuscript; S.J. revised the manuscript; S.J., S.W., and L.W. provided financial support and helped perform the analysis with constructive discussions. All authors have read and approved the final version of the manuscript.

Data availability

The raw data are available through the NCBI Sequence Read Archive (SRA) database, cataloged under accession number PRJNA1275011 (https://www.ncbi.nlm.nih.gov/). All relevant datasets in this article are available in the article and the supplementary material.

Conflicts of interest statement

The authors declare that they have no competing interests.

Supplementary material

Supplementary material is available at Horticulture Research online.

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