Exogenous methyl jasmonate and cytokinin antagonistically regulate lignin biosynthesis by mediating CsHCT expression in Camellia sinensis

• Published in: Protoplasma Vol. 260; no. 3; pp. 869 - 884
• Main Authors: Liu, Chun-Fang, Yang, Ni, Teng, Rui-Min, Li, Jing-Wen, Chen, Yi, Hu, Zhi-Hang, Li, Tong, Zhuang, Jing
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.05.2023; Springer Nature B.V
• Subjects: Biomedical and Life Sciences; Biosynthesis; Camellia sinensis; Cell Biology; Cytokinins; Cytokinins - metabolism; Gene expression; Gene Expression Regulation, Plant; Leaves; Life Sciences; Lignin; Lignin - metabolism; Methyl jasmonate; Original Article; Plant Leaves - metabolism; Plant Proteins - metabolism; Plant Sciences; Tea; Tea - metabolism; Zoology; HCT; Lignin; Expression profiling; Tea plant; Cytokinin; Methyl jasmonate
• ISSN: 0033-183X; 1615-6102
• DOI: 10.1007/s00709-022-01820-8

Tea plant, an important beverage crop, is cultivated worldwide. Lignification can improve the hardness of tea plant, which is of great significance for tea quality. Jasmonates (JAs) and cytokinin are plant hormones that control processes of plant development and secondary metabolite accumulation. Hydroxycinnamoyl–CoA shikimate/quinate hydroxycinnamoyl transferase (HCT) is primarily involved in lignin biosynthesis. The effects of exogenous application of JAs and cytokinin on lignin biosynthesis and related HCT gene expression profiles in tea plants are still unclear. In order to investigate the effects of exogenous JAs and cytokinin on lignin accumulation, anatomical structures, and CsHCT gene profiles in tea plants, we treated tea plants with methyl jasmonate (MeJA) and cytokinin (6-BA). MeJA and 6-BA treatments triggered the lignification at 6 and 12 d in tea leaves. The combined treatment resulted in an increase in lignin content at 6 d, which was 1.32 times of that at 0 d for ‘Mengshan 9.’ The CsHCTs in clade 2 ( CsHCT5 , CsHCT6 , CsHCT7 , and CsHCT8 ) were mainly expressed in leaves. We found that exogenous MeJA and cytokinin might be able to antagonistically regulate tea plant lignin accumulation through the mediation of CsHCT expression. This study revealed that HCTs play potential important roles involved in lignin biosynthesis of tea plant development and hormonal stimuli.