State Key Laboratory of Tea Plant Biology and Utilization, International Joint Laboratory on Tea Chemistry and Health Effects, Anhui Agricultural University, Hefei, Anhui, China.
Key Laboratory of Tea Plant Biology of Henan Province, College of Life Science, Xinyang Normal University, Xinyang, Henan, China.
Plant Biotechnol J. 2022 Nov;20(11):2089-2106. doi: 10.1111/pbi.13891. Epub 2022 Jul 26.
The tea plant is an economically important woody beverage crop. The unique taste of tea is evoked by certain metabolites, especially catechin esters, whereas their precise formation mechanism in different cell types remains unclear. Here, a fast protoplast isolation method was established and the transcriptional profiles of 16 977 single cells from 1st and 3rd leaves were investigated. We first identified 79 marker genes based on six isolated tissues and constructed a transcriptome atlas, mapped developmental trajectories and further delineated the distribution of different cell types during leaf differentiation and genes associated with cell fate transformation. Interestingly, eight differently expressed genes were found to co-exist at four branch points. Genes involved in the biosynthesis of certain metabolites showed cell- and development-specific characteristics. An unexpected catechin ester glycosyltransferase was characterized for the first time in plants by a gene co-expression network in mesophyll cells. Thus, the first single-cell transcriptional landscape in woody crop leave was reported and a novel metabolism pathway of catechin esters in plants was discovered.
茶树是一种经济价值很高的木本饮料作物。某些代谢物，特别是儿茶素酯，赋予了茶独特的风味，然而它们在不同细胞类型中的精确形成机制尚不清楚。在这里，建立了一种快速原生质体分离方法，并对来自第 1 叶和第 3 叶的 16977 个单细胞的转录谱进行了研究。我们首先基于六个分离组织鉴定了 79 个标记基因，并构建了转录组图谱，绘制了发育轨迹，并进一步描绘了叶片分化过程中不同细胞类型的分布以及与细胞命运转变相关的基因。有趣的是，在四个分支点发现了八个表达不同的基因共存。参与某些代谢物生物合成的基因表现出细胞和发育特异性特征。通过质体细胞中基因共表达网络，首次在植物中鉴定到一种具有独特功能的儿茶素酯糖基转移酶。因此，报告了木本作物叶片的第一个单细胞转录组图谱，并发现了植物中儿茶素酯的新代谢途径。
