title: The untranslated leader sequence of the barley lipoxygenase 1 (Lox1) gene confers embryo-specific expression.
abstract: The barley lipoxygenase 1 (Lox1) gene encodes a protein expressed in embryos during grain development and germination and in leaves after methyl-jasmonate (MeJA) treatment. Transient gene expression assays in germinating barley embryos were used to identify cis-regulatory elements involved in the embryo-specific expression of the Lox1 gene. Analysis of transcriptional or translational fusions between Lox1 5' upstream sequences and the gusA reporter gene indicated that the 5'-untranslated leader sequence was involved in embryo-specific expression. Replacement of the leader sequence from the aleurone-specific Chi26 gene with the Lox1 leader sequence resulted in a chimeric gene expressed at high levels in embryo as well as in aleurone cells. Insertion of the Lox1 leader sequence between the 35S minimum promoter (A domain -90/+8) and the gusA reporter gene greatly enhanced promoter activity in a tissue-specific manner. Deletion/replacement analysis of the Lox1 leader sequence, combined with transient expression in germinating embryos and in vitro transcription/translation assays, suggests that the Lox1 leader sequence contains cis-elements regulating qualitative (tissue-specific) and quantitative gene expression.
authors.affiliation: Carlsberg Research Laboratory, Copenhagen, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Rouster
authors.forename: J
authors.initials: J
authors.lastname: van Mechelen
authors.forename: V
authors.initials: V
authors.lastname: Cameron-Mills
mesh_terms: D000085:Acetates / Q000494:pharmacology; D001483:Base Sequence; D003517:Cyclopentanes / Q000494:pharmacology; D018744:DNA, Plant / Q000235:genetics; D004742:Enhancer Elements, Genetic; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D017930:Genes, Reporter; D018525:Germination / Q000235:genetics; D005966:Glucuronidase / Q000235:genetics; D001467:Hordeum / Q000196:embryology / Q000201:enzymology* / Q000235:genetics*; D008084:Lipoxygenase / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D054883:Oxylipins; D010937:Plant Growth Regulators / Q000494:pharmacology; D030821:Plants, Genetically Modified
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D018744:DNA, Plant; D054883:Oxylipins; D010937:Plant Growth Regulators; C072239:methyl jasmonate; D008084:Lipoxygenase; D005966:Glucuronidase