title: Duplicate maize Wrinkled1 transcription factors activate target genes involved in seed oil biosynthesis.
abstract: WRINKLED1 (WRI1), a key regulator of seed oil biosynthesis in Arabidopsis (Arabidopsis thaliana), was duplicated during the genome amplification of the cereal ancestor genome 90 million years ago. Both maize (Zea mays) coorthologs ZmWri1a and ZmWri1b show a strong transcriptional induction during the early filling stage of the embryo and complement the reduced fatty acid content of Arabidopsis wri1-4 seeds, suggesting conservation of molecular function. Overexpression of ZmWri1a not only increases the fatty acid content of the mature maize grain but also the content of certain amino acids, of several compounds involved in amino acid biosynthesis, and of two intermediates of the tricarboxylic acid cycle. Transcriptomic experiments identified 18 putative target genes of this transcription factor, 12 of which contain in their upstream regions an AW box, the cis-element bound by AtWRI1. In addition to functions related to late glycolysis and fatty acid biosynthesis in plastids, the target genes also have functions related to coenzyme A biosynthesis in mitochondria and the production of glycerol backbones for triacylglycerol biosynthesis in the cytoplasm. Interestingly, the higher seed oil content in ZmWri1a overexpression lines is not accompanied by a reduction in starch, thus opening possibilities for the use of the transgenic maize lines in breeding programs.
authors.affiliation: Université de Lyon, Ecole Normale Supérieure de Lyon, Université Lyon 1, IFR128 BioSciences Lyon Gerland, Unité Reproduction et Développement des Plantes, F-69364 Lyon, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Pouvreau
authors.forename: Sébastien
authors.initials: S
authors.lastname: Baud
authors.forename: Vanessa
authors.initials: V
authors.lastname: Vernoud
authors.forename: Valérie
authors.initials: V
authors.lastname: Morin
authors.forename: Cyrille
authors.initials: C
authors.lastname: Py
authors.forename: Ghislaine
authors.initials: G
authors.lastname: Gendrot
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Pichon
authors.forename: Jacques
authors.initials: J
authors.lastname: Rouster
authors.forename: Wyatt
authors.initials: W
authors.lastname: Paul
authors.forename: Peter M
authors.initials: PM
authors.lastname: Rogowsky
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D001483:Base Sequence; D005227:Fatty Acids / Q000378:metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D020131:Genes, Duplicate / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D005816:Genetic Complementation Test; D006019:Glycolysis / Q000235:genetics; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D010938:Plant Oils / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012639:Seeds / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism; D014280:Triglycerides / Q000096:biosynthesis; D003313:Zea mays / Q000235:genetics*
chemical_list: D005227:Fatty Acids; D010938:Plant Oils; D010940:Plant Proteins; D014157:Transcription Factors; D014280:Triglycerides