Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Apr;72(3):e12792.
doi: 10.1111/jpi.12792.

Melatonin delays dark-induced leaf senescence by inducing miR171b expression in tomato

Affiliations

Melatonin delays dark-induced leaf senescence by inducing miR171b expression in tomato

Kaixin Wang et al. J Pineal Res. 2022 Apr.

Abstract

Melatonin functions in multiple aspects of plant growth, development, and stress response. Nonetheless, the mechanism of melatonin in plant carbon metabolism remains largely unknown. In this study, we investigated the influence of melatonin on the degradation of starch in tomato leaves. Results showed that exogenous melatonin attenuated carbon starvation-induced chlorophyll degradation and leaf senescence. In addition, melatonin delayed leaf starch degradation and inhibited the transcription of starch-degrading enzymes after sunset. Interestingly, melatonin-alleviated symptoms of leaf senescence and starch degradation were compromised when the first key gene for starch degradation, α-glucan water dikinase (GWD), was overexpressed. Furthermore, exogenous melatonin significantly upregulated the transcript levels of several microRNAs, including miR171b. Crucially, the GWD gene was identified as a target of miR171b, and the overexpression of miR171b ameliorated the carbon starvation-induced degradation of chlorophyll and starch, and inhibited the expression of the GWD gene. Taken together, these results demonstrate that melatonin promotes plant tolerance against carbon starvation by upregulating the expression of miR171b, which can directly inhibit GWD expression in tomato leaves.

Keywords: carbon starvation; chlorophyll; growth; miRNAs; resistance; starch degradation; α-glucan water dikinase (GWD).

PubMed Disclaimer

References

REFERENCES

    1. Smith AM, Zeeman SC. Starch: a flexible, adaptable carbon store coupled to plant growth. Annu Rev Plant Biol. 2020;71:217-245.
    1. Smith AM, Stitt M. Coordination of carbon supply and plant growth. Plant Cell Environ. 2007;30(9):1126-1149.
    1. Yazdanbakhsh N, Sulpice R, Graf A, Stitt M, Fisahn J. Circadian control of root elongation and C partitioning in Arabidopsis thaliana. Plant Cell Environ. 2011;34(6):877-894.
    1. Graf A, Schlereth A, Stitt M, Smith AM. Circadian control of carbohydrate availability for growth in Arabidopsis plants at night. Proc Natl Acad Sci USA. 2010;107(20):9458-9463.
    1. Stitt M, Zeeman SC. Starch turnover: pathways, regulation and role in growth. Curr Opin Plant Biol. 2012;15(3):282-292.

MeSH terms

LinkOut - more resources