An early salicylic acid-, pathogen- and elicitor-inducible tobacco glucosyltransferase: role in compartmentalization of phenolics and H2O2 metabolism.
Treatment of tobacco cell suspension cultures with a fungal elicitor of defense responses resulted in an early accumulation of the phenylpropanoid glucosyltransferase TOGT, along with the rapid synthesis and secretion of scopolin, the glucoside of scopoletin. Elicitor-triggered extracellular accumulation of the aglycone scopoletin and of free caffeic and ferulic acids could only be revealed in the presence of diphenylene iodonium, an inhibitor of extracellular H2O2 production. Our results strongly support a role for TOGT in the elicitor-stimulated production of transportable phenylpropanoid glucosides, followed by the release of free antioxidant phenolics into the extracellular medium and subsequent H2O2 scavenging.
Chong
J
J
Institut de Biologie Moléculaire des Plantes du CNRS, Université Louis Pasteur, Strasbourg, France.
Baltz
R
R
Fritig
B
B
Saindrenan
P
P
D002109:Caffeic Acids / Q000378:metabolism; D002451:Cell Compartmentation; D002478:Cells, Cultured; D003373:Coumaric Acids / Q000378:metabolism; D004790:Enzyme Induction; D005110:Extracellular Space / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism; D005656:Fungal Proteins / Q000494:pharmacology*; D005964:Glucosyltransferases / Q000096:biosynthesis* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007424:Intracellular Fluid / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D010084:Oxidation-Reduction; D010636:Phenols / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology; D010947:Plants, Toxic; D020156:Salicylic Acid / Q000494:pharmacology*; D012603:Scopoletin / Q000378:metabolism; D014026:Nicotiana / Q000166:cytology / Q000201:enzymology* / Q000378:metabolism / Q000382:microbiology*; D014530:Uridine Diphosphate / Q000378:metabolism
D002109:Caffeic Acids; D003373:Coumaric Acids; D016166:Free Radical Scavengers; D005656:Fungal Proteins; D008562:Membrane Glycoproteins; D010636:Phenols; C091510:elicitor protein, Phytophthora megasperma; D014530:Uridine Diphosphate; C004999:ferulic acid; D006861:Hydrogen Peroxide; D005964:Glucosyltransferases; D012603:Scopoletin; D020156:Salicylic Acid; C040048:caffeic acid