Project description:Ozone pollution decreases plant growth and yield worldwide. Some of the effects are genetically-mediated and are reported to involve G-protein signaling pathways. Effects of ozone on gene expression were examined in wild-type and G-protein null mutants to determine affected genes and to determine differential responses that may help define affected pathways. We used microarrays to examine changes in gene expression in response to ozone exposure and identified distinct classes of up- and down-regulated genes in wild-type and G-protein null mutant genotypes.
Project description:Ozone pollution decreases plant growth and yield worldwide. Some of the effects are genetically-mediated and are reported to involve G-protein signaling pathways. Effects of ozone on gene expression were examined in wild-type and G-protein null mutants to determine affected genes and to determine differential responses that may help define affected pathways. We used microarrays to examine changes in gene expression in response to ozone exposure and identified distinct classes of up- and down-regulated genes in wild-type and G-protein null mutant genotypes. Columbia wild-type and G-protein null mutant gpa1-4/agb1-2 plants were exposed to 5 or 125 ppb ozone in controlled environment chambers for two days. Leaves were sampled after 3 h and 2 d of exposure to examine early and late gene expression changes.
Project description:Transcriptional profiling of the vegetative part of Arabidopsis comparing wild type with the shr scl23 scr triple mutant. The latter is produced by crossing the strong null alleles of shr (shr-2), scl23 (scl23-1) and scr (scr-5). The goal was to determine the effects of the GRAS transcription factors SHR, SCL23 and SCR on growth and development of the Arabidopsis shoot system by global transcriptome analysis.
Project description:How bacteria from the microbiota modulate the physiology of its host is an important question to address. Previous work revealed that the metabolic status of Arabidopsis thaliana was crucial for the specific recruitment of Streptomycetaceae into the microbiota. Here, the Arabidopsis-Actinacidiphila interaction was further depicted by inoculating axenic Arabidopsis with Actinacidiphila cocklensis DSM 42063 or Actinacidiphila bryophytorum DSM 42138(previously named Streptomyces cocklensis and Streptomyces bryophytorum). We demonstrated that these two bacteria colonize A. thaliana wild-type plants, but their colonization efficiency was reduced in a chs5 mutant with defect in isoprenoid, phenylpropanoids and lipids synthesis. We observed that those bacteria affect the growth of the chs5 mutant but not of the wild-type plants. Using a mass spectrometry-based proteomic approach, we showed a modulation of the Arabidopsis proteome and in particular its components involved in photosynthesis or phytohormone homeostasis or perception by A. cocklensis and A. bryophytorum. This study unveils specific aspects of the Actinacidiphila-Arabidopsis interaction, which implies molecular processes impaired in the chs5 mutant and otherwise at play in the wild-type. More generally, this study highlights complex and distinct molecular interactions between Arabidopsis thaliana and bacteria belonging to the Actinacidiphila genus.