Ethylamine, beyond the synthetic precursor of theanine: CsCBF4-CsAlaDC module promoted ethylamine synthesis to enhance osmotic tolerance in tea plants.

The tea plant (Camellia sinensis) is a perennial green plant, and its tender leaves are rich in secondary metabolites, such as theanine. Ethylamine (EA), a small amine, is an important prerequisite for theanine synthesis. However, beyond its involvement in theanine synthesis, the other physiological functions of EA in tea plants remain unknown.