Figure 6.

Upstream factors that regulate L-theanine hydrolysis in tea leaves during withering. The moisture content of detached tea leaves decreases with time. The expression of CsWRKY40 increases, thus activating the promoter of CsPDX2.1, increasing the expression of the L-theanine hydrolase gene, and reducing L-theanine content. In addition, ABA accumulates and may inhibit L-theanine content by activating CsWRKY40 or other pathways. The solid red line represents the research content of this paper, whereas the dotted black line represents the speculated pathway.