title: Functional characterization of the three genes encoding 1-deoxy-D-xylulose 5-phosphate synthase in maize.
abstract: The 1-deoxy-D-xylulose 5-phosphate synthase (DXS) enzyme catalyses the first biosynthetic step of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. In plants the MEP pathway is involved in the synthesis of the common precursors to the plastidic isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate, in plastids. DXS is recognized as limiting this pathway and is a potential target for manipulation to increase various isoprenoids such as carotenoids. In Zea mays three dxs genes exist that encode plastid-targeted functional enzymes. Evidence is provided that these genes represent phylogenetically distinctive clades conserved among plants preceding monocot-dicot divergence. There is differential accumulation for each dxs gene transcript, during development and in response to external signals such as light. At the protein level, the analysis demonstrates that in Z. mays, DXS protein is feedback regulated in response to the inhibition of the pathway flow. The results support that the multilevel regulation of DXS activity is conserved in evolution.
authors.affiliation: Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001 Chamilpa. Apdo. Postal 510-3 Cuernavaca, Morelos 62210, Mexico.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Cordoba
authors.forename: Helena
authors.initials: H
authors.lastname: Porta
authors.forename: Analilia
authors.initials: A
authors.lastname: Arroyo
authors.forename: Carolina
authors.initials: C
authors.lastname: San Román
authors.forename: Luis
authors.initials: L
authors.lastname: Medina
authors.forename: Manuel
authors.initials: M
authors.lastname: Rodríguez-Concepción
authors.forename: Patricia
authors.initials: P
authors.lastname: León
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D008027:Light; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018087:Plastids / Q000378:metabolism; D014166:Transferases / Q000235:genetics*; D003313:Zea mays / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development
chemical_list: D010940:Plant Proteins; D014166:Transferases; C109461:deoxyxylulose-5-phosphate synthase