National Center for
5E8L: Crystal Structure Of Geranylgeranyl Pyrophosphate Synthase 11 From Arabidopsis Thaliana
Structural analyses of short-chain prenyltransferases identify an evolutionarily conserved GFPPS clade in Brassicaceae Plants
Mol Plant (2015)
Terpenoids are the largest and most diverse class of plant specialized metabolites, which function in diverse physiological processes during plant development. In the biosynthesis of plant terpenoids, short-chain prenyltransferase (SC-PT), together with terpene synthase (TPS), play a role in determining terpenoid diversity. SC-PTs biosynthesize prenyl pyrophosphates with different chain lengths and these compounds are the direct precursors of terpenoids. Arabidopsis thaliana possesses a subgroup of SC-PTs whose functions are not clearly known (we focus on 10 geranylgeranyl pyrophosphate synthase-like (GGPPSL) proteins here, which are commonly thought to produce GGPP [C20]). In this study, we find that a subset members of the Arabidopsis GGPPSL gene family have undergone neo-functionalization: GGPPSL6, 7, 9, and 10 mainly have geranylfarnesyl pyrophosphate synthase activity ([C25]; renamed as AtGFPPS1, 2, 3 and 4), and GGPPSL8 produces even longer chain prenyl pyrophosphate (>/= C30, renamed as polyprenyl pyrophosphate synthase 2, AtPPPS2). By solving the crystal structures of AtGFPPS2, AtPPPS2 and AtGGPPS11, we reveal the product chain-length determination mechanism of SC-PTs and describe it as a "three floors" model. Using this model, we identified a novel GFPPS clade distributed in Brassicaceae plants. In addition, we find that the GFPPS gene typically occurs in tandem with a gene encoding a TPS, forming a GFPPS-TPS gene cluster.