Slow and steady wins the race: the negative regulators of ethylene biosynthesis in horticultural plants

Abstract

The gaseous hormone ethylene controls a variety of physiological processes in horticultural plants, including fruit ripening and elongation, flower development and senescence, and responses to stresses. The functions of ethylene in these processes are intimately linked to its precise biosynthesis, which is finely tuned by a complex network of positive and negative regulators. While significant progress has been made in understanding the roles of positive regulators in ethylene biosynthesis, the negative regulators of ethylene biosynthesis has only recently begun to receive more focus. Ethylene biosynthesis is a simple two-step reaction in land plants, committed by two dedicated enzymes, 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) and ACC oxidase (ACO). Over the past decade, a growing number of research has identified a wide range of transcriptional, posttranscriptional and epigenetic negative regulators for ACS and/or ACO in horticultural plants, greatly enhancing our understanding of the intricate network that modulates ethylene production. In this review, we provide a comprehensive overview of the negative regulators that mediate ethylene biosynthesis in horticultural plants, with respect to their functions and molecular mechanisms, and their responses to external environmental stimuli or internal growth signals.

Acknowledgements

This work was supported by the National Key Research and Development Program of China (2022YFD2100102 to KC), the National Natural Science Foundation of China (32402638 to DL) and the Zhejiang Provincial Natural Science Foundation of China (LQ24C020001 to DL).

Author contributions

D.L. and K.C. conceived and designed this review article. D.L., S.Z. R.D., and K.C. wrote the manuscript. D.L. drew the figure and made the tables. All authors were involved in reviewing and editing the manuscript, and approved the final manuscript.

Data availability

Not applicable to this review.

Conflict of interest statement

The authors declare that they have no competing interests.

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