Project description:Experiments were achieved on Arabidopsis thaliana. Transcriptional profiling of roots and shoots from plants treated with lead were compared to plants treated in similar conditions without lead. Four weeks old A. thaliana seedlings were treated in hydroponic cultures with Pb during 3 days, by adding or not 40 µM Pb(NO3)2.
Project description:A whole transcriptome (RNA-seq) study of Arabidopsis shoots under iron sufficient, deficient and resupply conditions was carried out to determine the genes that are iron-regulated in the shoots.
Project description:Plant hormones and small secretory peptides often function as environmental stress mediators. Some recent reports indicate that small secretory peptides, such as CLAVATA3/EMBRYO SURROUNDING REGION-RELATED (CLE), also function as mediators of environmental stimuli. CLE2 is induced in roots by light depriviation. Plants without functional CLE2 showed a chlorosis phenotype when grown under shade. Here, we identified specific genes downstream of CLE2 in roots and shoots with transformed Arabidopsis plants.
Project description:We performed small RNA-seq (sRNA-seq) study of Arabidopsis shoots under iron-sufficient (+Fe), iron deficient (-Fe) and iron resupply (Fe resupply) conditions to investigate and identify sRNAs whose expression is regulated by iron deficiency.
Project description:Arabidopsis wild-type plants (Col-0 accession) were grown on control (+Fe+P) for 7 days on 0.1X MS then transferred to three different medium: control (+Fe+P), iron deficiency (-Fe+P), and iron and phosphate deficiency conditions (-Fe-P). Shoots were collected 39 h, 52 h and 76 h after the transfer. For RNA-seq experiments, three biological replicates were used for each time point (39h, 52h and 76h) and each condition (+Fe+P, -Fe+P and -Fe-P) for a total of 27 samples.
Project description:Plant cells contain different O-acetylserine(thiol)lyase (OASTL) enzymes involved in Cys biosynthesis and located in different subcellular compartments. These enzymes are made up of a complex variety of isoforms resulting in different subcellular Cys pools. To unravel the contribution of cytosolic Cys to plant metabolism, we characterized the knockout oas-a1.1 and osa-a1.2 mutants, deficient in the most abundant cytosolic OASTL isoform in Arabidposis thaliana. Total intracellular Cys and glutathione concentrations were reduced, and the glutathione redox state was shifted in favour of its oxidized form. Interestingly, the capability of the mutants to chelate heavy metals did not differ from that of the wild type, but the mutants have an enhanced sensitivity to Cd. With the aim of establishing the metabolic network most influenced by the cytosolic Cys pool, we used the ATH1 GeneChip for evaluation of differentially expressed genes in the oas-a1.1 mutant grown under non-stress conditions. The transcriptomic footprints of mutant plants had predicted functions associated with various physiological responses that are dependent on reactive oxygen species and suggested that the mutant was oxidatively stressed. To further elucidate the specific function(s) of the OAS-A1 isoform in the adaptation response to cadmium we extended the trasncriptome experiment to the wild type and oas-a1.1 mutant plants exposed to Cd. The comparison of transcriptomic profiles showed a higher proportion of genes with altered expression in the mutant than in the wild type, highlighting up-regulated genes identified as of the general oxidative stress response rather than metal-responsive genes. Wild type and oas-a1.1 mutant plants were grown hydroponically and, after a two-week acclimation period, the roots and shoots were harvested separately. Total RNA was then prepared and analyzed using the Affymetrix-Arabidopsis ATH1GeneChip array. Three biological replicates were performed for each sample. We made two different comparisons to classify the differently expressed genes in the mutant plant: oas-a1.1 roots versus wild-type roots and oas-a1.1 shoots versus wild-type shoots. Hydroponically-grown wild type and oas-a1.1 mutant plants were further treated with 50µM CdCl2 and 18h-treated-roots and 24h-treated-shoots were harvested. Total RNA was then prepared and analyzed using the Affymetrix-Arabidopsis ATH1GeneChip array. Three biological replicates were performed for each sample. Different comparisons were performed as follows: 18h Cd-treated wild type roots versus untreated wild type roots; 24h Cd-treated wild type shoots versus untreated wild type shoots; 18h Cd-treated oas-a1.1 roots versus untreated oas-a1.1 roots; 24h Cd-treated oas-a1.1 shoots versus untreated oas-a1.1 shoots; 18h Cd-treated oas-a1.1 roots versus 18h Cd-treated wild type roots; 24h Cd-treated oas-a1.1 shoots versus 24h Cd-treated wild type shoots