Identification of a novel cis-regulatory element for UV-B-induced transcription in Arabidopsis.
Ultraviolet-B light (UV-B) regulates the expression of genes in a wavelength- and fluence rate-dependent fashion. A signaling pathway consisting of CONSTITUTIVE PHOTOMORPHOGENESIS 1 (COP1) and UV RESISTANCE LOCUS 8 (UVR 8) mediates responsiveness to longer wavelength, low intensity UV-B light-activating, for example, HY5 gene expression. By contrast, transcription of another group of genes, including ANAC13, modulated by shorter wavelength, higher intensity UV-B is controlled by a yet unknown and largely COP1-independent signaling cascade. Here we provide evidence by promoter deletion analysis, and characterization of genetic mutants displaying aberrant expression patterns, that two cis-regulatory elements, designated MRE(ANAC13) and UVBox(ANAC13), are required for maximal UV-B induction of the ANAC13 gene in transgenic plants. These elements are located in the proximal 150-bp region of the ANAC13 promoter. They show no significant similarity to each other; the putative MRE(ANAC13) (-AACCTT-) is closely related to MRE(CHS) (-AACCTA-) found in the CHALCONE SYNTHASE (CHS) gene, whereas UVBox(ANAC13) (with core sequence CAAG) represents a novel cis-regulatory element. The novel UVBox(ANAC13) sequence is significantly enriched in the promoter region of a subset of UV-B-induced genes with similar activation properties as ANAC13. In addition, we demonstrate that expression of a chimeric gene containing only the dimerized 12-mer containing UVBox(ANAC13) fused to a minimal CaMV35S promoter/luciferase reporter is (i) efficiently induced by shorter wavelength, higher intensity UV-B, but (ii) does not respond either to longer wavelength UV-B and red light or (iii) to abscisic acid treatment and osmotic, salt, heat and cold stresses.
Safrany
Judit
J
Agricultural Biotechnology Center, Szent-Gyorgyi A. 4, H-2100 Gödöllo, Hungary.
Haasz
Veronika
V
Mate
Zoltan
Z
Ciolfi
Andrea
A
Feher
Balazs
B
Oravecz
Attila
A
Stec
Agnieszka
A
Dallmann
Geza
G
Morelli
Giorgio
G
Ulm
Roman
R
Nagy
Ferenc
F
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D008027:Light; D008969:Molecular Sequence Data; D017354:Point Mutation; D011401:Promoter Regions, Genetic / Q000235:genetics; D050436:Regulatory Elements, Transcriptional / Q000235:genetics*; D014158:Transcription, Genetic / Q000528:radiation effects*; D044767:Ubiquitin-Protein Ligases; D014466:Ultraviolet Rays
D029681:Arabidopsis Proteins; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases