Root-specific expression of CsNPF2.3 is involved in modulating fluoride accumulation in tea plant (Camellia sinensis)

Abstract

Fluoride (F) is a nonessential but potentially harmful element for plants, especially when present in excess. The tea plant is known for its ability to hyperaccumulate F from the soil and eventually accumulates in the leaves; however, how the tea plant transports F to the leaves remains unclear. Here, we found that Se can significantly decrease the transport efficiency of F from root to leaf. Therefore, RNA-Sequencing was performed on tea roots cotreated with selenite and fluoride, and then we isolated a plasma membrane-localized F transporter CsNPF2.3 from tea plant roots and examined its role in transport of F in tea plants. The results showed that CsNPF2.3 exhibited F transport activity when heterologously expressed in yeast. Expression pattern analysis revealed that CsNPF2.3 is expressed in epidermal cells, cortex cells, and xylem parenchyma cells in roots. Overexpression of CsNPF2.3 in tea roots significantly increased F content in the root, stem, and leaf, and enhanced the transport efficiency of F from root to leaf. Furthermore, in nine tea cultivars, CsNPF2.3 expression in the root was significantly positively correlated with F content in the leaf and root, and the transport efficiency of F from root to leaf. Altogether, these findings suggest that CsNPF2.3 was involved in uptake and transport of F in tea plants.

Acknowledgements

This work was supported by the National Key Research and Development Program of China (No. 2021YFD1601100), the Research Funds of Joint Research Center for Food Nutrition and Health of IHM (No. 2023SJY01), Excellent scientific research and innovation team of universities in Anhui Province (No. 2022AH010055), the earmarked fund for CARS (No. CARS-19), and Natural Science Foundation of China (No. 32172636).

Author contributions

H.C., Z.Z., and X.W. provided invaluable guidance and supervision throughout the writing process. H.N. conducted experiments, analyzed data, and wrote the manuscript. J.W., Z.L., and Y.D. assisted in conducting experiments. Q.C., C.P., G.C., R.H., and X.W. revised the manuscript.

Data availability

All relevant data in this study are incorporated into the article and its supplementary file.

Conflict of interest statement

The authors declare no competing financial interests.

Supplementary Data

Supplementary data is available at Horticulture Research online.

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