title: Pleiotropic effects of the wheat dehydrin DHN-5 on stress responses in Arabidopsis.
abstract: We have previously reported that transgenic Arabidopsis plants overexpressing the wheat dehydrin DHN-5 show enhanced tolerance to osmotic stresses. In order to understand the mechanisms through which DHN-5 exerts this effect, we performed transcriptome profiling using the Affymetrix ATH1 microarray. Our data show an altered expression of 77 genes involved mainly in transcriptional regulation, cellular metabolism, stress tolerance and signaling. Among the up-regulated genes, we identified those which are known to be stress-related genes. Several late embryogenesis abundant (LEA) genes, ABA/stress-related genes (such as RD29B) and those involved in pathogen responses (PR genes) are among the most up-regulated genes. In addition, the MDHAR gene involved in the ascorbate biosynthetic pathway was also up-regulated. This up-regulation was correlated with higher ascorbate content in two dehydrin transgenic lines. In agreement with this result and as ascorbate is known to be an antioxidant, we found that both transgenic lines show enhanced tolerance to oxidative stress caused by H₂O₂. On the other hand, multiple types of transcription factors constitute the largest group of the down-regulated genes. Moreover, three members of the jasmonate-ZIM domain (JAZ) proteins which are negative regulators of jasmonate signaling were severely down-regulated. Interestingly, the dehydrin-overexpressing lines exhibit less sensitivity to jasmonate than wild-type plants and changes in regulation of jasmonate-responsive genes, in a manner similar to that in the jasmonate-insensitive jai3-1 mutant. Altogether, our data unravel the potential pleiotropic effects of DHN-5 on both abiotic and biotic stress responses in Arabidopsis.
authors.affiliation: Laboratory of Plant Protection and Improvement, Centre of Biotechnology of Sfax/University of Sfax, BP '1177' 3018 Sfax-Tunisia.
authors.forename: Faïçal
authors.initials: F
authors.lastname: Brini
authors.forename: Akiko
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Lobna
authors.initials: L
authors.lastname: Jlaiel
authors.forename: Shin
authors.initials: S
authors.lastname: Takeda
authors.forename: Tokunori
authors.initials: T
authors.lastname: Hobo
authors.forename: Huy Q
authors.initials: HQ
authors.lastname: Dinh
authors.forename: Tsukaho
authors.initials: T
authors.lastname: Hattori
authors.forename: Khaled
authors.initials: K
authors.lastname: Masmoudi
authors.forename: Moez
authors.initials: M
authors.lastname: Hanin
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000222:Adaptation, Physiological; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D003517:Cyclopentanes / Q000494:pharmacology; D015536:Down-Regulation / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D006861:Hydrogen Peroxide / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D009997:Osmotic Pressure; D054883:Oxylipins / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology*; D059467:Transcriptome; D014908:Triticum / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation / Q000235:genetics
chemical_list: D003517:Cyclopentanes; D054883:Oxylipins; D010940:Plant Proteins; C070556:dehydrin proteins, plant; C011006:jasmonic acid; D000040:Abscisic Acid; D006861:Hydrogen Peroxide