ABA–ethylene crosstalk accelerates persimmon fruit softening via induction of DkNAC26 and DkNAC28

Abstract

Ethylene and abscisic acid (ABA) play crucial roles in the ripening and softening of persimmon fruit, and they can promote each other to accelerate the softening process. However, the underlying molecular mechanisms remain to be further elucidated. In this study, a transcription factor NAM ATAF1/2, CUC26 ( DkNAC26) induced by ethylene was identified. It could increase the content of ABA in persimmon fruit by promoting the expression of ABA synthesis-related gene DkNCED2+ 3′, thereby reducing fruit firmness. On the other hand, ABA could induce the expression of transcription factor DkNAC28, which binds to the promoter region of the ethylene biosynthesis gene DkACS1, leading to an earlier ethylene burst and consequently accelerating fruit softening. This study elucidates the functional roles of two transcriptional activators, DkNAC26 and DkNAC28, in regulating the biosynthesis of ethylene and ABA and reveals a molecular mechanism through which these two hormones interact to promote fruit softening, providing a new perspective for hormone crosstalk that drives rapid softening in persimmon.

Acknowledgements

This research was supported by the National Natural Science Foundation of China (32272780), the Yunnan Provincial Young and Middle-aged Academic and Technical Leader Reserve Talent Program (No. 202405 AC350101), the Chinese Universities Scientific Fund (2452022344), and the start-up funds of Northwest A&F University awarded to Q.Z. (Z1090222008) and Y.X. (Z1090124082). We are grateful to Dr. J. Zhang, Ms. J. Zhao, and Ms. A. Tang for professional technical assistance at the Horticultural Science Research Center, Northwest A&F University, Yangling, China.

Author contributions

X.Y.X.: Data curation, formal analysis, and writing-original draft. Y.F., S.H.R., and Z.X.R.: Investigation. Y.D.D. and Q.G.Z.: Supervision. G.H., N.J.S., X.R.Y., X.F.L., and Q.G.Z.: writing-review and editing.

Data availability

Transcriptome data during the study were deposited in the NCBI under accession number PRJNA1392662 (the transcriptomic analysis of persimmon fruit treated with ethylene and control) and PRJNA1280690(the transcriptomic analysis of persimmon fruit treated with ABA and control).

Conflicts of interest statement

The authors declare that they have no conflicts of interest.

Supplementary material

Supplementary material is available at Horticulture Research online.

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