Project description:Lipo-chitooligosaccharides (LCOs) produced by N2-fixing rhizobacteria initiate host nodule formation. Foliar application of LCOs has been shown to induce stress-related genes under optimal growth conditions. To study the effects of LCO foliar spray under stressed conditions, soybean seedlings grown at optimal temperature were exposed to sub-optimal temperature. After a 5-day acclimation period, the first trifoliolate leaves were sprayed with 10-7 M LCO (NodBj-V (C18:1, MeFuc)) produced by Bradyrhizobium japonicum, and harvested at 0 and 48 h following treatment. Microarray analysis was performed using Affymetrix GeneChip® Soybean Genome Arrays. A total of 147 genes were differentially expressed 48 h after LCO treatment, including a number of stress-related genes and transcription factors. In addition, during the 48 h following treatment, hundreds of genes were differentially expressed in LCO-treated plants, indicating that the dynamic soybean foliar transcriptome was highly responsive to LCO treatment. The microarray data was supported by quantitative real-time PCR data.
Project description:Lipo-chitooligosaccharides (LCOs) produced by N2-fixing rhizobacteria initiate host nodule formation. Foliar application of LCOs has been shown to induce stress-related genes under optimal growth conditions. To study the effects of LCO foliar spray under stressed conditions, soybean seedlings grown at optimal temperature were exposed to sub-optimal temperature. After a 5-day acclimation period, the first trifoliolate leaves were sprayed with 10-7 M LCO (NodBj-V (C18:1, MeFuc)) produced by Bradyrhizobium japonicum, and harvested at 0 and 48 h following treatment. Microarray analysis was performed using Affymetrix GeneChip® Soybean Genome Arrays. A total of 147 genes were differentially expressed 48 h after LCO treatment, including a number of stress-related genes and transcription factors. In addition, during the 48 h following treatment, hundreds of genes were differentially expressed in LCO-treated plants, indicating that the dynamic soybean foliar transcriptome was highly responsive to LCO treatment. The microarray data was supported by quantitative real-time PCR data. Soybean seedlings grown at optimal temperature (25 °C) were exposed to sub-optimal temperature (15 °C). After a 5-day acclimation period, the first trifoliolate leaves were sprayed with 10-7 M LCO (NodBj-V (C18:1, MeFuc)) produced by Bradyrhizobium japonicum, and harvested at 0 and 48 h following treatment. Total RNA was extracted and microarray analysis was performed using Affymetrix GeneChip® Soybean Genome Arrays.
Project description:Heat stress is one of the primary abiotic stresses that limit crop production . Grape is a popular cultivated fruit with high economic value throughout the world, and whose growth and development is often influenced by high temperature. Alternative splicing (AS) is a widespread mechanism increasing transcriptome complexity and proteome diversity. We conducted high temperature treatments (35oC, 40oC and 45oC) on grapevines (Vitis vinifera), and assessed proteomic and transcriptomic (especially AS)changes in leaves. We found that nearly 70% of the genes were alternatively spliced under high temperature. Intron retention (IR), exon skipping (ES) and alternative donor/acceptor sites were markedly induced under different high temperatures. IR was the most abundant up- and down-regulated AS event; moreover, IR events at 40 and 45oC were far higher than those at 35oC. These results indicated AS, especially IR, is an important posttranscriptional regulatory during grape leaf responses to high temperature. Proteomic analysis showed that protein levels of the RNA binding proteins SR45, SR30, and SR34, and the nuclear ribonucleic protein U1A in grape leaves gradually rose as ambient temperature increased. The results also revealed why AS events occurred more frequently under high temperature in grape leaves. After integrating transcriptomic and proteomic data, we found that HSPs and some important transcript factors such as MBF1c and HSFA2 were mainly involved in heat tolerance in grape through up-regulating transcriptional and translational levels, and were especially modulated by AS. The results provide the first simultaneous evidence for grape leaf responses to high temperature at transcriptional, posttranscriptional and translational levels.
2017-03-07 | GSE89113 | GEO
Project description:Transcriptomic data of soybean leaf tissues under drought stress
Project description:When pollen lands on a receptive stigma, it germinates and extends a tube inside the transmitting tissue of the pistil to deliver the sperm cells for double fertilization. The growth of the pollen tube triggers significant alterations in its gene expression. The extent to which these changes occur in the vegetative cell or extend to the sperm cells transported by the tube is unclear, but important to determine since sperm cells are believed to acquire a competency for fertilization during pollen-pistil interactions. To address these questions, we compared the transcriptomes of Arabidopsis thaliana sperm cells and vegetative nuclei isolated from mature pollen grains with those isolated from in vitro grown pollen tubes. Importantly, we also compared with transcriptomes of sperm cells obtained from pollen tubes grown under semi in vivo conditions where tubes passed through a pistil section. Our data shows that extensive transcriptomic changes occur in sperm cells during pollen tube growth, some of which are elicited only as sperms are carried through the pistil. Their analysis reveals a host of previously unidentified transcripts that may facilitate sperm maturation and gamete fusion. The vegetative cell undergoes even more extensive transcriptomic reprogramming during pollen tube growth, mainly through the upregulation of genes associated with pollen tube growth and vesicle-mediated transport. Interestingly, ATAC-seq data shows that the promoters of genes up-regulated in sperm during pollen tube growth are already accessible in sperm chromatin of mature pollen grains, suggesting pre-configured promoter accessibility. This study's expression data can be further explored here: https://bar.utoronto.ca/eFP-Seq_Browser/.
Project description:Comparing the transcriptomic responses between the Mycobacterium avium subspecies paratuberculosis (MAP) leuD mutant with the parent strain K-10 under different environmental stresses: nutrition, temperature, anaerobic conditions, high- and low- pH conditions.
2013-02-16 | GSE36053 | GEO
Project description:Procambarus clarkii under high temperature stress
Project description:Soybean is an important economic crop for human diet, animal feeds and biodiesel due to high protein and oil content. Its productivity is significantly hampered by salt stress, which impairs plant growth and development by affecting gene expression, in part, through epigenetic modification of chromatin status. However, little is known about epigenetic regulation of stress response in soybean roots. Here, we used RNA-seq and ChIP-seq technologies to study the dynamics of genome-wide transcription and histone methylation patterns in soybean roots under salt stress. 8798 soybean genes changed their expression under salt stress treatment. Whole-genome ChIP-seq study of an epigenetic repressive mark, histone H3 lysine 27 trimethylation (H3K27me3), revealed the changes in H3K27me3 deposition during the response to salt stress. Unexpectedly, we found that most of the inactivation of genes under salt stress is strongly correlated with the de novo establishment of H3K27me3 in various parts of the promoter or coding regions where there is no H3K27me3 in control plants. In addition, the soybean histone modifiers were identified which may contribute to de novo histone methylation and gene silencing under salt stress. Thus, dynamic chromatin regulation, switch between active and inactive modes, occur at target loci in order to respond to salt stress in soybean. Our analysis demonstrates histone methylation modifications are correlated with the activation or inactivation of salt-inducible genes in soybean roots.
Project description:The transcriptomic analysis was evaluated using RNA-seq of salmon challenged with the birnavirus IPNv under two different thermal conditions: (a) constant temperature (mean temperature 15 ± 0.9 ºC, “No-Fever”) and (b) temperature gradient (mean temperature 15 ± 7.4 ºC, “Fever”). In parallel, fish in another tank were treated by adding 100 ml virus free cell culture supernatant to the water (mean temperature 15 ± 7.4 ºC, "mock-infected"). We identified a specific transcriptomic signature for each group in the RNA-seq data and identifying a set of key components that control inflammatory modulation during behavioural fever upon viral infection in mobile ectotherms.