Flavan-3-ol Galloylation-Related Functional Gene Cluster and the Functional Diversification of Paralogs in sp.

The high accumulation of galloylated flavan-3-ols in . is a noteworthy phenomenon. We identified a flavan-3-ol galloylation-related functional gene cluster in tannin-rich plant ., which included and gene clusters. We investigated the possible correlation between the accumulation of metabolites and the expression of and . The results revealed that , , and accumulated galloylated -flavan-3-ols (EGCG), galloylated -flavan-3-ols (GCG), and hydrolyzed tannins, respectively; however, did not accumulate any galloylated compounds. exhibited no expression of or , whereas the other three species of exhibited various expression patterns. This indicated that the functions of the paralogs of vary. Enzymatic analysis revealed that was neofunctionalized as a noncatalytic chaperone paralog, a type of chaerone-like protein, associating with flavan-3-ol galloylation; moreover, was subfunctionalized in association with the galloylation of - and -flavan-3-ols. In , an homolog was noted with mutations in two cysteine residues forming a disulfide bond, which suggested that this homolog was defunctionalized. The findings of this study improve our understanding of the functional diversification of paralogs in .