Hydroxycinnamoyl-CoA: shikimate hydroxycinnamoyl transferase (HCT) divides the mass flux to H, G and S units in monolignol biosynthesis and affects lignin content. Ten HCT homologs were identified in the (Torr. & Gray) genome. Both genome duplication and tandem duplication resulted in the expansion of HCT orthologs in . Comprehensive analysis including motif analysis, phylogenetic analysis, expression profiles and co-expression analysis revealed the divergence and putative function of these candidate . and were identified as likely involved in lignin biosynthesis. and are likely to be involved in plant development and the response to cold stress. Similar functional divergence was also identified in Enzymatic assay of PtoHCT1 showed that PtoHCT1 was able to synthesize caffeoyl shikimate using caffeoyl-CoA and shikimic acid as substrates.