Effect of shade treatment on theanine biosynthesis in Camellia sinensis seedlings
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Theanine synthetase (TS) is a key enzyme involved in theanine biosynthesis. In our recent study, it has been revealed that theanine biosynthesis derived from nitrogen metabolism in tea (Camellia sinensis) plants can be influenced by shading treatment. The expression patterns of CsTS protein in the roots and shoots of tea seedlings were examined by western blot using a self-prepared polyclonal antibody with high specificity and sensitivity. The effect of long-term shade treatment on the levels of theanine synthesis was also investigated using roots and shoots of tea seedlings. Levels of theanine and total free amino acids gradually increased in shoots, reaching their maximum after 22 days of treatment (DOT). The immunoblotting analysis suggested that CsTS protein levels increased gradually up to 22 DOT and expression remained at a high level, except after 1 DOT where levels were low in both roots and shoots. The increased theanine concentration we observed in the shading treatment may be due to increased nitrogen assimilation and reduced theanine catabolism under shade conditions.
KeywordsCamellia sinensis Theanine synthetase Shade Theanine Amino acid
This research was supported by the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT1101) and Natural Science Foundation of China (No. 31170283).
- Crozier A, Yokota T, Jaganath IB, Marks SC, Saltmarsh M, Clifford MN (2006) Secondary metabolites in fruits, vegetables, beverages and other plant-based dietary components. In: Crozier A, Clifford MN, Ashihara H (eds) Plant secondary metabolites—occurrence, structure and role in the human diet. Blackwell, Oxford, pp 208–302CrossRefGoogle Scholar
- Sakai S (1975) Recent studies and problems of photosynthesis of tea plant. JARQ 9:101–106Google Scholar
- Wojciechowska R, Siwek P (2006) The effect of shading on nitrate metabolism in stalks and blades of celery leaves (Apium graveolens L. var. dulce). Folia Horticulturae 18:25–35Google Scholar
- Yamaguchi S, Ninomiya K (2000) Umami and food palatability. J Nutr 130:921–926Google Scholar
- Zhang WJ, Liang YR, Zhang FZ, Chen CS, Zhang YG, Chen RB, Weng BQ (2004) Effects on the yield and quality of oolong tea by covering with shading. net. J Tea Sci 24:276–282 (in Chinese)Google Scholar