A key gene discovered in tea plants for enhancing aluminum accumulation resistance
image: The gene silencing experiment of CsWRKY17 in tea plant leaves. (A) Expression patterns of CsPMEs and CsWRKY17 under different Al concentrations. (B) CsPME6 promoter cloning. (C) Tea shoots were immersed with 20 μM asODN for 48 h, with sODN serving as a control. (D) The expression levels of CsWRKY17 and CsPME6. (E) Changes in PME activity and cell wall Al content. Asterisks denote a significant difference (*P < 0.05; **P < 0.01). Image link: https://academic.oup.com/view-large/figure/515836801/uhaf085f6.tif
Credit: Horticulture Research
Tea (Camellia sinensis) is an essential agricultural product consumed worldwide. While the plant has a remarkable ability to accumulate aluminum (Al) in its leaves, this trait can be a double-edged sword. On the one hand, Al helps the plant grow by aiding in nutrient uptake, but on the other hand, excessive aluminum can pose a risk to human health. Despite extensive research into the physiological mechanisms of Al uptake, the genetic and molecular pathways remain largely unexplored. Based on the challenges of excessive Al accumulation, it is crucial to study the molecular pathways involved and develop strategies to reduce Al content in tea products.
Published (DOI: 10.1093/hr/uhaf085) in Horticulture Research in March 2025, this study led by researchers from multiple institutions, including Hubei Academy of Agricultural Sciences and the Chinese Academy of Agricultural Sciences, presents groundbreaking findings on the genetic regulation of Al accumulation in tea plants. By combining quantitative trait locus (QTL) mapping and comparative transcriptomics, the researchers identified CsWRKY17 as a key gene associated with increased Al accumulation in tea plant leaves. The findings are set to pave the way for developing new tea plant varieties with lower Al content, enhancing consumer safety.
Through an integrative approach combining QTL mapping and transcriptomic analysis, the study identified CsWRKY17, a WRKY transcription factor gene, as critical in regulating aluminum accumulation. This gene was found to be highly correlated with Al levels in tea leaves, and its overexpression led to increased pectin deesterification, which in turn promoted aluminum binding in the cell walls. Using Arabidopsis thaliana, a model plant, to overexpress CsWRKY17, the team observed increased sensitivity to Al stress and higher Al content in the leaves. Further experiments revealed that CsWRKY17 directly activates the CsPME6 gene, which encodes a pectin methylesterase involved in the demethylesterification of pectin. This process is crucial for aluminum sequestration in tea plant cell walls. The study also identified key regulatory networks involving cell wall metabolism that are activated in response to Al, offering new insights into how plants manage metal stress.
"Understanding the molecular mechanisms behind aluminum accumulation in plants is critical for agricultural sustainability," says Dr. Yingxin Mao, a lead researcher in the study. "Our discovery of CsWRKY17 as a central regulator in this process not only enhances our understanding of aluminum metabolism in tea plants but also opens doors for developing varieties with reduced aluminum content, which is vital for both plant health and consumer safety."
The implications of this research extend beyond basic science and into practical applications for tea plant breeding. By targeting CsWRKY17 and related genes in breeding programs, it will be possible to develop tea varieties that accumulate less aluminum in their leaves, making them safer for consumption. Additionally, the findings could be applied to other crops with aluminum tolerance mechanisms, potentially reducing the risks associated with aluminum accumulation in food crops worldwide. This research contributes significantly to the ongoing efforts to improve the safety and sustainability of agricultural products.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhaf085
Funding information
This work was supported by the National Key Research and Development Program of China (2021YFD1601100), China Agriculture Research System of MOF and MARA (CARS-19), the Chinese Academy of Agricultural Sciences through the Agricultural Science and Technology Innovation Program (CAAS-ASTIP-2021-TRICAAS), the Jiangxi Province Talent Plan (jxsq2023102020), Yunnan Province of Science and Technology Department (202449CE340010), and the Innovation Center Fund for Agricultural Science and Technology in Hubei Province of China (2023-620-005-001).
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.