Gibberellins involved in fruit ripening and softening by mediating multiple hormonal signals in tomato

Abstract

The phytohormone ethylene is well known for its important role in the ripening of climacteric fruit, such as tomato ( Solanum lycopersicum ). However, the role and mode of action of other plant hormones in climacteric fruit ripening regulation are not fully understood. Here, we showed that exogenous GA treatment or increasing endogenous gibberellin content by overexpressing the gibberellin synthesis gene SlGA3ox2 specifically in fruit tissues delayed tomato fruit ripening, whereas treatment with the GA biosynthesis inhibitor paclobutrazol (PAC) accelerated fruit ripening. Moreover, exogenous ethylene treatment cannot completely reverse the delayed fruit ripening phenotype. Furthermore, exogenous GA treatment of ethylene signalling mutant Never ripe ( Nr ) or SlEBF3 -overexpressing lines still delayed fruit ripening, suggesting that GA involved in fruit ripening partially depends on ethylene. Transcriptome profiling showed that gibberellin affect the ripening of fruits by modulating the metabolism and signal transduction of multiple plant hormones, such as auxin and abscisic acid, in addition to ethylene. Overall, the results of this study provide new insight into the regulation of gibberellin in fruit ripening through mediating multiple hormone signals.

Acknowledgements

This work was supported in part by the Natural Science Foundation of Sichuan Province, China (2023NSFSC1991), the Institutional Research Funding of Sichuan University (2022SCUNL105), the National Natural Science Foundation of China (No.31772372, No.32172643, No.32172271), the Applied Basic Research Category of Science and Technology Program of Sichuan Province (2021YFQ0071; 2022YFSY0059-1; 2021YFYZ0010-5-LH), and the Technology Innovation and Application Development Program of Chongqing (cstc2021jscx-cylhX0001).

Author contributions

M.L. planned and designed the research; M.W., K.L., H.L., Y.L., Y.Z., D.S., and H. D performed the experiments. Y.Z. and Y.W. analysed the data. M.L. and M.W. wrote the manuscript.

Data availability

All relevant data and figures in this study can be found within the article and its supporting materials.

Conflict of interest statement:

The authors declare no conflict of interest.

Supplementary data

Supplementary data is available at Horticulture Research online.

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