Root-specific theanine metabolism and regulation at the single-cell level in tea plants (Camellia sinensis)

作者：Shijia Lin, Yiwen Zhang, Shupei Zhang, Yijie Wei, Mengxue Han, Yamei Deng, Jiayi Guo, Biying Zhu, Tianyuan Yang, Enhua Xia, Xiaochun Wan, William J. Lucas, Zhaoliang Zhang · 发表于：eLife · 年份：2024 · DOI：10.7554/elife.95891 · 被引用次数：19 · 研究领域：Tea Polyphenols and Effects、Plant Gene Expression Analysis、Plant Molecular Biology Research

Root-synthesized secondary metabolites are critical quality-conferring compounds of foods, plant-derived medicines, and beverages. However, information at a single-cell level on root-specific secondary metabolism remains largely unexplored. L-Theanine, an important quality component of tea, is primarily synthesized in roots, from which it is then transported to new shoots of tea plant. In this study, we present a single-cell RNA sequencing (scRNA-seq)-derived map for the tea plant root, which enabled cell-type-specific analysis of glutamate and ethylamine (two precursors of theanine biosynthesis) metabolism, and theanine biosynthesis, storage, and transport. Our findings support a model in which the theanine biosynthesis pathway occurs via multicellular compartmentation and does not require high co-expression levels of transcription factors and their target genes within the same cell cluster. This study provides novel insights into theanine metabolism and regulation, at the single-cell level, and offers an example for studying root-specific secondary metabolism in other plant systems.