Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China.
Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, No. 723 Xingke Road, Tianhe District, Guangzhou 510650, China.
J Agric Food Chem. 2021 Jan 27;69(3):1039-1048. doi: 10.1021/acs.jafc.0c07220. Epub 2021 Jan 19.
The plant hormone abscisic acid (ABA) accumulates in tea leaves under dehydration stress during the withering process. However, the mechanism underlying ABA biosynthesis regulation remains largely unclear. In the present study, we found increased expression of ABA biosynthesis genes under dehydration stress during postharvest processing of tea. Furthermore, dehydration stress promoted ABA accumulation by increasing histone acetylation of ABA anabolism genes but by decreasing the levels of histone H3 lysine 9 dimethylation and DNA methylation of ABA biosynthesis genes. We screened candidate regulators of histone deacetylation and DNA methylation under dehydration stress. Taken together, our results indicate a role for epigenetic modifications during postharvest processing of tea.
植物激素脱落酸（ABA）在萎凋过程中会在脱水胁迫下在茶叶中积累。然而，ABA 生物合成调控的机制在很大程度上仍不清楚。在本研究中，我们发现，在茶叶收获后加工过程中，脱水胁迫会导致 ABA 生物合成基因表达增加。此外，脱水胁迫通过增加 ABA 合成基因的组蛋白乙酰化水平，同时降低组蛋白 H3 赖氨酸 9 二甲基化和 ABA 生物合成基因的 DNA 甲基化水平，促进 ABA 的积累。我们筛选了脱水胁迫下组蛋白去乙酰化和 DNA 甲基化的候选调控因子。总之，我们的研究结果表明，组蛋白修饰和 DNA 甲基化在茶叶收获后加工过程中起作用。
