title: Gene regulation by low level UV-B radiation: identification by DNA array analysis.
abstract: UV-B radiation alters transcript levels of various defence genes and photosynthetic genes in plants. Utilising a DNA array with 5000 ESTs and cDNAs from Arabidopsis thaliana, 70 genes were found to show a greater than two-fold induction or repression of transcript levels. Six genes (MEB5.2, PyroA, Ubq3, Lhcb6, F5D21.10 and the gene for an RNA polymerase II subunit) were tested for stress specific gene regulation on northern blots with RNA from plants exposed to low dose UV-B radiation, ozone or wounding. Transcript levels for PyroA, Uhq3 and the gene for a RNA polymerase II subunit were all specifically increased by UV-B. MEB5.2 mRNA levels also rose, whereas Lhcb6 and FSD21.10 transcript levels decreased under all stresses. The PyroA gene product in fungi is needed for biosynthesis of pyridoxine, and might have a role in protection against singlet oxygen. The Ubq3 gene encodes the ubiquitin protein that is attached to proteins destined for degradation. MEB5.2 and F5D21.10 represent novel gene products whose function have not yet been identified. Pairwise comparisons between the UV-B inducible promoters have identified a series of elements present in the MEB5.2 and PyroA promoters, absent from promoters of genes for early phenylpropanoid metabolism and that may be responsible for modulating their UV-B responses.
authors.affiliation: Biochemistry and Biophysics, Department of Chemistry, Göteborg University, P.O. Box 462, SE-405 30 Göteborg, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Brosché
authors.forename: Mary A
authors.initials: MA
authors.lastname: Schuler
authors.forename: Irina
authors.initials: I
authors.lastname: Kalbina
authors.forename: Lynn
authors.initials: L
authors.lastname: Connor
authors.forename: Ake
authors.initials: A
authors.lastname: Strid
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000528:radiation effects; D001483:Base Sequence; D018744:DNA, Plant / Q000235:genetics; D020224:Expressed Sequence Tags; D015971:Gene Expression Regulation, Enzymologic / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects*; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D010940:Plant Proteins / Q000235:genetics; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000235:genetics; D014466:Ultraviolet Rays
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins; D012319:RNA Polymerase II