Project description:To gain insight into how AtCAPE1 regulates salt response, we investigated the gene expression profiles of wild-type (Ler) and proatcape1 mutant seedlings in the presence and absence of 125 mM NaCl by microarray analysis.
Project description:To gain insight into how AtCAPE1 regulates salt response, we investigated the gene expression profiles of wild-type (Ler) and proatcape1 mutant seedlings in the presence and absence of 125 mM NaCl by microarray analysis. Ten seedlings were grown vertically on the mesh attached on 1/2 MS medium for 10 days. Seedlings with the mesh were transferred to a new petri dish and then covered by buffer-saturated filter papers with 1/2 MS liquid medium (Control) or with 125 mM NaCl (Salt). Salt-treated seedlings (n=10 for each treatment) were sampled after 12 h. Three independent experiments were performed for the microarray analysis.
Project description:Accumulation of unfolded/misfolded proteins in endoplasmic reticulum (ER) elicits a well conserved response called the Unfolded Protein Response (UPR), which triggers the up-regulation of downstream genes involved in protein folding, vesicle trafficking, and ER-Associated Degradation (ERAD). Although the dynamic transcriptomic responses and underlying major transcriptional regulators in ER stress response in plants have been well established, the proteome changes induced by ER stress have not been reported in plants. In the current study, we found that the Arabidopsis Ler ecotype is more sensitive to ER stress than the Col ecotype. Quantitative mass spectrometry analysis with Tandem Mass Tag (TMT) isobaric labeling showed that totally 7439 and 7035 proteins were identified from Col and Ler seedlings, with 88 and 113 differentially regulated (FC>1.3 or <0.7, P<0.05) proteins by ER stress in Col and Ler, respectively. Among them, 40 proteins were commonly up-regulated in Col and Ler, of which 10 were not up-regulated in bzip28 bzip60 double mutant (Col background) plants. Of the 19 specifically up-regulated proteins in Col comparing to that in Ler, components in ERAD, N-glycosylation, vesicle trafficking and molecular chaperones were represented. Quantitative RT-PCR showed that genes encoding 7 out of 19 proteins were not up-regulated (FC>1.3 or <0.7, P<0.05) by ER stress in both ecotypes while genes encoding 12 out of 19 proteins were up-regulated by ER stress with no obvious differences in fold change between Col and Ler. Our results experimentally demonstrated the robust ER stress response at proteome level in plants and revealed differentially regulated proteins that may contribute to differed ER stress sensitivity between Col and Ler ecotypes in Arabidopsis.
Project description:Arabidopsis ecotypes of Sha and Ler showed differences in tolerance to salinity stress. A previous study indicated that a premature stop codon resulting in a truncated Response to ABA and Salt 1 (RAS1) protein in Sha contributes to the increased salt tolerance relative to Ler ecotype. Sha exhibited higher germination rates and longer roots on MS plate, presumably due to the decreased ABA sensitivity in Sha. More Sha plants also survived in soil after salt treatment with relatively lower electrolyte leakage when compared to Ler. Transcriptome analysis revealed that expression levels of many genes were changed between Sha and Ler ecotypes and by salt treatments. About 500 transcripts were commonly changed by at least one salinity effect and one ecotype effect, and 171 of them were co-regulated by all four comparisons. Transcripts involved in redox, secondary metabolism, auxin metabolism, photosynthesis, cell wall, and protein synthesis were mainly down-regulated by salinity effects, while transposable element genes, microRNA and antisense sequences, histone superfamily genes, and biotic stress related genes were significantly changed by Sha ecotype effects and only slightly by salinity. Several metabolic pathways such as stress, TCA, hormone/lipid/secondary metabolism, redox, development, and GO terms involved in stress, oxidation, and defense response were enriched by both salinity and ecotype effects. Ninety-five highly inducible genes were identified as candidates of RAS1 target genes and the functions involved hormone metabolism, biotic stress, RNA, DNA synthesis, protein metabolism, cell, and microRNA metabolism. All these results indicated that the Sha ecotype was possibly preconditioned to abiotic stress relative to Ler through regulation of signaling pathways and stress responsive gene expression. These comparative transcriptomic and analytical results also confirm the complexity of ABA responses and salt stress tolerance mechanisms, and they suggest additional targets for improving tolerance. Ten days old seedlings of two Arabidopsis ecotypes, Sha and Ler, were treated with 100 mM NaCl on MS plate. Plant materials were collected for RNA extraction at 4th days after treatments.
Project description:Soybean is one of the main sources of oil worldwide. Salinity severely affect its yield. GmSIN1 is a NAC transcription factor coding gene. Its overexpression (OE) transgenic lines greatly improved the yield in both common and saline fields. This study focuses on founding changes genes between GmSIN1 OE transgenic seedlings and control seedlings under salt stress or non-salt stress conditions. Illumina Solexa sequencing platform was used for the comparative analysis of transcriptome profiles in the roots and leaves of GmSIN1 OE transgenic seedlings and WEI6823 (control) seedlings under mock or 150 mM NaCl treatment for 6 hrs.
Project description:Arabidopsis ecotypes of Sha and Ler showed differences in tolerance to salinity stress. A previous study indicated that a premature stop codon resulting in a truncated Response to ABA and Salt 1 (RAS1) protein in Sha contributes to the increased salt tolerance relative to Ler ecotype. Sha exhibited higher germination rates and longer roots on MS plate, presumably due to the decreased ABA sensitivity in Sha. More Sha plants also survived in soil after salt treatment with relatively lower electrolyte leakage when compared to Ler. Transcriptome analysis revealed that expression levels of many genes were changed between Sha and Ler ecotypes and by salt treatments. About 500 transcripts were commonly changed by at least one salinity effect and one ecotype effect, and 171 of them were co-regulated by all four comparisons. Transcripts involved in redox, secondary metabolism, auxin metabolism, photosynthesis, cell wall, and protein synthesis were mainly down-regulated by salinity effects, while transposable element genes, microRNA and antisense sequences, histone superfamily genes, and biotic stress related genes were significantly changed by Sha ecotype effects and only slightly by salinity. Several metabolic pathways such as stress, TCA, hormone/lipid/secondary metabolism, redox, development, and GO terms involved in stress, oxidation, and defense response were enriched by both salinity and ecotype effects. Ninety-five highly inducible genes were identified as candidates of RAS1 target genes and the functions involved hormone metabolism, biotic stress, RNA, DNA synthesis, protein metabolism, cell, and microRNA metabolism. All these results indicated that the Sha ecotype was possibly preconditioned to abiotic stress relative to Ler through regulation of signaling pathways and stress responsive gene expression. These comparative transcriptomic and analytical results also confirm the complexity of ABA responses and salt stress tolerance mechanisms, and they suggest additional targets for improving tolerance.
Project description:High salinity is one of the major environmental factors, which hampers plant growth, development and productivity. To better understand the regulatory mechanisms by which plants cope with salt stress, we used genetic approaches to identify salt hypersensitive mutant 9 (sahy9), a new allele of apum23, in Arabidopsis thaliana. The sahy9/apum23 mutant seedlings display postgemination developmental arrest and later become bleached under agar plates supplemented with various salt stressors. Transcriptomic and proteomic analyses of the salt-treated sahy9/apum23 and wild-type seedlings revealed differential expression of genes with similar functional categories, primarily including cellular and metabolic processes, and abiotic and biotic stress responses. However, the consistency of gene expression at both transcript and protein levels is low (), suggesting the involvement of posttranscriptional processing in salt response. Furthermore, the altered gene/protein expression mediated by SAHY9/APUM23 in salt sensitivity is involved in several functional groups, particularly in ABA biosynthesis and signaling, abiotic stress response, LEA proteins, and ribosome biogenesis-related genes. Importantly, NCED3, a key gene involved in ABA biosynthesis, and major ABA responsive marker genes, such as RD20 and RD29B, are down-regulated at both transcript and protein levels in sahy9/apum23 under salt stress. Consistently, lower contents of ABA and proline, and expression changes of a subset of LEA proteins also support the nature of sahy9/apum23 showing salt hypersensitivity. Collectively, these data suggest that SAHY9/APUM23-mediated salt response is associated with ABA signaling pathway and its downstream stress responsive or tolerant genes.
Project description:Salt and PEG tolerances of 70 Arabidopsis accessions were screened. Five commonly used Arabidopsis accessions (C24, Col, Ler, SHA, Ws) were selected for further analysis. The results showed that SHA and C24 were relatively tolerant, while Ler and Ws were relatively susceptible to both salt and PEG stress. Transcriptomic analysis revealed that 4105 to 8782 genes exhibited significant expression level changes among five accessions in the presence and absence of stress treatments. The function of these genes were involved in stress response, ROS and metabolic pathways. The detailed networks affected by salt and osmotic stresses were dissected.