Salinity is an abiotic stress that substantially limits crop production worldwide. To identify salt stress tolerance determinants, we screened for Arabidopsis mutants that are hypersensitive to salt stress and designated these mutants as short root in salt medium (rsa). One of these mutants, rsa3-1, is hypersensitive to NaCl and LiCl but not to CsCl or to general osmotic stress. Reactive oxygen species (ROS) over-accumulate in rsa3-1 plants under salt stress. Gene expression profiling with Affym ...[more]
Project description:Salt stress is one of the most severe environmental conditions which cause huge losses in crop production worldwide. We identified an essential regulator of salt stress RSA3 and used the Affymetrix whole-genome arrays to study the effect of rsa3-1 mutation on global gene expression under salt stress. A set of genes differentially expressed in rsa3-1 under salt stress are identified. Six-day-old seedlings of Arabidopsis thaliana wild type (Columbia gl1 expressing RD29A::LUC transgene) and rsa3-1 mutant seedlings subjected to salt stress at 120 mM NaCl for 24 h were used for total RNA extraction and hybridizations with Affymetrix ATH1 GeneChips. There are two biological replicates per genotype.
Project description:To analyze global changes in AS under salt stress, we obtained high-coverage (~200 times) RNA sequencing data from Arabidopsis thaliana seedlings that were treated with different concentrations of NaCl. Our study provided a comprehensive view of AS under salt stress and revealed novel insights into the potential roles of AS in plant response to salt stress.
Project description:Arabidopsis thaliana is a glycophyte with a low salt tolerance, while Eutrema is a halophyte with a very high salt tolerance. To elucidate the transcriptional basis of this difference, we performed hydroponis culture experiments where we grew plants under control conditions (25 mM NaCl) or under salt stress (200 mM NaCl for both species, 500 mM for Eutrema). Salt concentration was increased for the stress treatments by increments of 50 mM per day (25 mM on the first day). Plants were grown at the final NaCl concentration for an additional week, when rosettes were harvested for RNA isolation.Expression patterns were compared between treatments and between species. In total, 15 samples were hybridized. They were derived from three independent biological experiments (replicate_1 to replicate_3). Controlds were grown at 25 mM NaCl, salt stressed plants at either 200 mM NaCl or 500 mM NaCl.
Project description:Biotic and abiotic stresses limit agricultural yields, and plants are often simultaneously exposed to multiple stresses. Combinations of stresses such as heat and drought or cold and high light intensity, have profound effects on crop performance and yeilds To analyze such responses, we initially compared transcriptome changes in ten Arabidopsis thaliana ecotypes using cold, heat, high light, salt and flagellin treatments as single stress factors or their double combinations. Arabidopsis thaliana plants of ecotypes (Col, Ler, C24, Cvi, Kas1, An1, Sha, Kyo2, Eri and Kond) were subjected to the following stress treatments: Salt, Cold, Heat, High Light (HL), Salt+Heat, Salt+HL, Cold+HL, Heat+HL, as well as FLG (Flagellin, flg22 peptide), Cold+FLG, Heat+FLG
Project description:To investigate differences in plant responses to salt and ABA stimulus, differences in gene expression in Arabidopsis in response to salt and ABA were compared using an Agilent oligo microarray. Four-week-old Arabidopsis thaliana ecotype Columbia (Col-0) seedlings were treated with either 150 mM NaCl or 10 μM ABA for 6 hours; unstressed seedlings (control sample) were collected in parallel to avoid the possible effects of circadian rhythms. The results revealed that 31 genes were up regulated by both NaCl and ABA stress, and 23 genes were down-regulated by these stressors. To provide further validation of our microarray experiment data, ten genes from this signature were quantified in the same RNA samples by quantitative real-time PCR. Differentially expression genes of Arabidopsis thaliana were measured under salt stressed, ABA stressed and normal condition for 6 hours, respectively. Three independent experiments were performed at each treatment using different plants for each experiment.
Project description:Lipo-chitooligosaccharide (LCO) and thuricin 17 (Th17) are two bacterial compounds that have been shown to positively influence plant growth of both legumes and non-legumes. Arabidopsis thaliana responded positively to treatment with the bacterial signal compounds LCO and Th17 in the presence of salt stress (up to 250 mM NaCl). Shotgun proteomics of unstressed and 250 mM NaCl stressed A. thaliana rosettes (7 days post stress) in combination with the LCO and Th17 revealed many known, putative, hypothetical and unknown proteins. Overall, carbon and energy metabolic pathways were affected under both unstressed and salt stressed conditions when treated with these signals. PEP carboxylase, Rubisco-oxygenase large subunit, pyruvate kinase, and proteins of photosystem I and II were some of the noteworthy proteins enhanced by the signals, along with other stress related proteins. These findings suggest that the proteome of A. thaliana rosettes is altered by the bacterial signals tested, and more so under salt stress, thereby imparting a positive effect on plant growth under high salt stress. The roles of the identified proteins are discussed here in relation to salt stress adaptation, which, when translated to field grown crops can be a crucial component and of significant importance in agriculture and global food production.