title: Glutathione and a UV light-induced glutathione S-transferase are involved in signaling to chalcone synthase in cell cultures.
abstract: UV irradiation stimulates expression of the gene encoding the key enzyme chalcone synthase (CHS), which leads to the generation of protective flavonoids in parsley cell cultures. CHS transcripts increase after 3 to 4 hr, and early genes are involved in the signal transduction to the CHS promoter. By using the fluorescent differential display technique in a large-scale screening, several early UV light-induced genes were isolated. Of these, a novel glutathione S-transferase (PcGST1) is induced within 2 hr and precedes CHS expression. Overexpression of PcGST1 in transformed cell lines containing a CHS promoter/luciferase reporter (CHS-LUC) affected the onset of LUC transcription. Supplementing these cell lines with glutathione immediately stimulated CHS-LUC expression within 2 hr in dark-incubated cells and resulted in a biphasic induction profile in UV-irradiated cells. Our data indicate the involvement of glutathione and PcGST1 in early events of a UV light-dependent signal transduction pathway to CHS. In this context, the oxidative status of a cell acts as a central regulating element.
authors.affiliation: Biologisches Institut II/Botanik, Albert-Ludwigs-Universitaet, D-79104 Freiburg, Schaenzlestrasse 1, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Loyall
authors.forename: K
authors.initials: K
authors.lastname: Uchida
authors.forename: S
authors.initials: S
authors.lastname: Braun
authors.forename: M
authors.initials: M
authors.lastname: Furuya
authors.forename: H
authors.initials: H
authors.lastname: Frohnmeyer
mesh_terms: D000217:Acyltransferases / Q000235:genetics*; D000595:Amino Acid Sequence; D019661:Apiaceae / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D002478:Cells, Cultured; D017124:Conserved Sequence; D004790:Enzyme Induction / Q000187:drug effects / Q000528:radiation effects; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D005978:Glutathione / Q000494:pharmacology*; D005982:Glutathione Transferase / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D007527:Isoenzymes / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D008156:Luciferases / Q000235:genetics; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D007527:Isoenzymes; D008156:Luciferases; D000217:Acyltransferases; C020141:flavanone synthetase; D005982:Glutathione Transferase; D005978:Glutathione