A Qualitative Proteome-Wide Lysine Succinylation Profiling of Tea Revealed its Involvement in Primary Metabolism

Lysine succinylation of proteins has potential impacts on protein structure and function, which occurs on post-translation level. However, the information about the succinylation of proteins in tea plants is limited. In the present study, the significant signal of succinylation in tea plants was found by western blot. Subsequently, we performed a qualitative analysis to globally identify the lysine succinylation of proteins using high accuracy nano LC-MS/MS combined with affinity purification. As a result, a total of 142 lysine succinylation sites were identified on 86 proteins in tea leaves. The identified succinylated proteins were involved in various biological processes and a large proportion of the succinylation sites were presented on proteins in the primary metabolism, including glyoxylate and dicarboxylate metabolism, TCA cycle and glycine, serine and threonine metabolism. Moreover, 10 new succinylation sites were detected on histones in tea leaves. The results suggest that succinylated proteins in tea plants might play critical regulatory roles in biological processes, especially in the primary metabolism. This study not only comprehensively analyzed the lysine succinylome in tea plants, but also provided valuable information for further investigating the functions of lysine succinylation in tea plants.