A Qualitative Proteome-wide Lysine Succinylation Profiling of Tea Revealed Its Involvement in Primary Metabolism

Background: Lysine succinylation of proteins has potential impacts on protein structure and function, which occurred on post-translation level. However, the information about the lysine 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 qualitative analyses to globally identify lysine succinylation substrates by using high accuracy nano LC-MS/MS combined with affinity purification. Results: As a result, a total of 142 lysine succinylation sites were identified in 86 proteins. The identified succinylated proteins are involved in various biological processes and a large proportion of the succinylation sites are present on proteins in the primary metabolism pathway, including glyoxylate and dicarboxylate metabolism, the tricarboxylic acid (TCA) cycle and glycine, serine and threonine metabolism. Moreover, 10 new succinylated sites on histones were detected in tea plants either. Conclusions: These results suggested that succinylated proteins in tea plants might play critical regulatory roles in biological processes, especially in the primary metabolism. This study not only globally analysed the functional annotation of lysine succinylation in tea plants, but also provided valuable information for further investigating the functions of lysine succinylation in tea plants.