title: Assembly of an evolutionarily new pathway for α-pyrone biosynthesis in Arabidopsis.
abstract: Plants possess arrays of functionally diverse specialized metabolites, many of which are distributed taxonomically. Here, we describe the evolution of a class of substituted α-pyrone metabolites in Arabidopsis, which we have named arabidopyrones. The biosynthesis of arabidopyrones requires a cytochrome P450 enzyme (CYP84A4) to generate the catechol-substituted substrate for an extradiol ring-cleavage dioxygenase (AtLigB). Unlike other ring-cleavage-derived plant metabolites made from tyrosine, arabidopyrones are instead derived from phenylalanine through the early steps of phenylpropanoid metabolism. Whereas CYP84A4, an Arabidopsis-specific paralog of the lignin-biosynthetic enzyme CYP84A1, has neofunctionalized relative to its ancestor, AtLigB homologs are widespread among land plants and many bacteria. This study exemplifies the rapid evolution of a biochemical pathway formed by the addition of a new biological activity into an existing metabolic infrastructure.
authors.affiliation: Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Jing-Ke
authors.initials: JK
authors.lastname: Weng
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.forename: Huaping
authors.initials: H
authors.lastname: Mo
authors.forename: Clint
authors.initials: C
authors.lastname: Chapple
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D053898:Biosynthetic Pathways; D020134:Catalytic Domain; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D049308:Dioxygenases / Q000235:genetics / Q000378:metabolism; D019143:Evolution, Molecular; D020440:Gene Duplication; D018745:Genome, Plant; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D010649:Phenylalanine / Q000378:metabolism; D010802:Phylogeny; D018547:Plant Stems / Q000378:metabolism; D030821:Plants, Genetically Modified; D011753:Pyrones / Q000737:chemistry / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D011753:Pyrones; D010649:Phenylalanine; D003577:Cytochrome P-450 Enzyme System; D049308:Dioxygenases; C574756:LigB protein, Arabidopsis; C574755:cytochrome P-450 84A4 protein, Arabidopsis