Integrated Transcriptomic and Metabolomic Analyses Shed Light on the Regulation of Aromatic Amino Acid Biosynthesis in a Novel Albino Tea (Camellia sinensis) Mutation

作者：Ying Gao, Shipeng Li, Xiao‐Jia Zhang, Shuwei Yu, Xinyu Liu, Changbo Yuan, Yuantao Yao, F. J. Zhang, Lubin Song · 发表于：Current Issues in Molecular Biology · 年份：2025 · DOI：10.3390/cimb47080644 · 被引用次数：2 · 研究领域：Plant Gene Expression Analysis、Photosynthetic Processes and Mechanisms、Genomics and Phylogenetic Studies

Off-white or yellowish shoots are common in tea plants (Camellia sinensis L.), and such albino variations are often accompanied by metabolic reprogramming, including increased contents of amino acids and lower levels of polyphenols. Nonetheless, the molecular mechanisms that underlie these albino variations remain to be fully clarified. Here, we examined the ultrastructural characteristics of novel, naturally occurring, yellowish mutated tea leaves and performed metabolomic analyses on green and albino leaves and stems. Then, transcriptomic analyses were also conducted on green and albino leaves to investigate the mechanistic basis of the albino variation. As expected, the cells of albino tea leaves contained fewer and smaller chloroplasts with disorganized thylakoids and smaller starch granules. Widely targeted metabolomics analysis revealed 561 differentially abundant metabolites between green and albino leaves and stems, but there was little difference between green and albino stems. Then, RNA sequencing of green and albino leaves revealed downregulation of genes associated with light harvesting and photosynthesis, and integration of the metabolomic and transcriptomic results indicated that biosynthesis of aromatic amino acids (AAAs) was strongly upregulated in albino leaves. To gain additional insight into the molecular basis of the increased AAA levels, Oxford Nanopore long-read sequencing was performed on green and albino leaves, which enabled us to identify differences...