title: Isolation and characterization of the CYP71D16 trichome-specific promoter from Nicotiana tabacum L.
abstract: Trichomes are specialized epidermal cells that produce secretions that are thought to provide a first line of defence against pests and pathogens. Many trichome-secreted compounds are used commercially as flavourings, medicines, etc. Described here is the cloning and characterization of the promoter of a tobacco trichome-specific P450 gene, CYP71D16. This promoter is shown to direct the specific expression of the reporter gene, beta-glucuronidase (GUS), in glandular trichomes of Nicotiana tabacum cv. T.I. 1068 at all developmental stages. With the full promoter, GUS activity was predominantly in the gland cell, with less in the stalk cell adjacent to the gland, and in lower stalk cells. GUS staining was also observed in the most distal trichome stalk cells of non-glandular trichomes found on variety T.I. 1112. Promoter deletion analysis revealed that the region from -223 to +111 bp is sufficient to direct trichome-specific expression, but not strong gland expression. Examination of the literature suggests that this is the first characterized trichome-specific-promoter shown to function at all stages of plant development. This promoter may provide efficient bioengineering to enhance pest and pathogen resistance, and for molecular farming based on the trichome gland system.
authors.affiliation: Plant Physiology/Biochemistry/Molecular Biology Program, Agronomy Department, 200L THRI, University of Kentucky, Lexington, KY 40546-0236, USA.
authors.forename: Erming
authors.initials: E
authors.lastname: Wang
authors.forename: Susheng
authors.initials: S
authors.lastname: Gan
authors.forename: George J
authors.initials: GJ
authors.lastname: Wagner
mesh_terms: D001483:Base Sequence; D022081:Cell Surface Extensions / Q000235:genetics*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005470:Fluorometry; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D006651:Histocytochemistry; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000302:isolation & purification; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D013379:Substrate Specificity; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D003577:Cytochrome P-450 Enzyme System; D005966:Glucuronidase