Project description:Purpose:Identification of genes and miRNAs responsible for salt tolerance in upland cotton (Gossypium hirsutum L.) would help reveal the molecular mechanisms of salt tolerance. We performed physiological experiments and transcriptome sequencing (mRNA-seq and small RNA-seq) of cotton leaves under salt stress using Illumina sequencing technology. And quantitative reverse transcription polymerase chain reaction (qRT–PCR) methods and to evaluate protocols for optimal high-throughput data analysis Methods:We investigated two distinct salt stress phases—dehydration (4 h) and ionic stress (osmotic restoration; 24 h)—that were identified by physiological changes of 14-day-old seedlings of two cotton genotypes, one salt tolerant and the other salt sensitive, during a 72-h NaCl exposure. A comparative transcriptomics approach was used to monitor gene and miRNA differential expression at two time points (4 and 24 h) in leaves of the two cotton genotypes under salinity conditions. Results:During a 24-h salt exposure, 819 transcription factor unigenes were differentially expressed in both genotypes, with 129 unigenes specifically expressed in the salt-tolerant genotype. Under salt stress, 108 conserved miRNAs from known families were differentially expressed at two time points in the salt-tolerant genotype. Conclusions:Our comprehensive transcriptome analysis has provided new insights into salt-stress response of upland cotton. The results should contribute to the development of genetically modified cotton with salt tolerance.
Project description:Soil salinity is a major environmental stress that restricts crop growth and yield. Here, crucial proteins and biological pathways were investigated under salt-stress and recovery conditions in Tritipyrum “Y1805” to explore its salt-tolerance mechanism. In total, 44 and 102 differentially expressed proteins (DEPs) were identified in “Y1805” under salt-stress and recovery conditions, respectively. A proteome-transcriptome-associated analysis revealed that the expression patterns of 13 and 25 DEPs were the same under salt-stress and recovery conditions, respectively. “Response to stimulus”, “antioxidant activity”, “carbohydrate metabolism”, “amino acid metabolism”, “signal transduction”, “transport and catabolism” and “biosynthesis of other secondary metabolites” were present under both conditions in “Y1805”. In addition, “energy metabolism” and “lipid metabolism” were recovery-specific pathways, while “antioxidant activity”, and “molecular function regulator” under salt-stress conditions, and “virion” and “virion part” during recovery, were “Y1805”-specific compared with the salt-sensitive wheat “Chinese Spring”. “Y1805” contained 83 specific DEPs related to salt-stress responses. The strong salt tolerance of “Y1805” could be attributed to the strengthened cell walls, reactive oxygen species scavenging, osmoregulation, phytohormone regulation, transient growth arrest, enhanced respiration, ammonium detoxification, transcriptional regulation and error information processing. These data will facilitate an understanding of the molecular mechanisms of salt tolerance and aid in the breeding of salt-tolerant wheat.
Project description:By comparing the transcriptome results of the control strain and the mutant strain under bile salt stress, the genes with large differential expression changes were analyzed in depth and combined with experiments to explore how the mutant genes were regulated by stress to cope with bile salt stress
Project description:RSS1 is required for maintenance of meristematic activity under salinity conditions in rice. We carried out transcriptome analysis using shoot basal tissues in wild type and rss1-2 grown under non-stress and salt-stress conditions.
Project description:Soil salinity is a major production constrain for agricultural crops, especially in Oryza sativa (rice). Analyzing physiological effect and molecular mechanism under salt stress is key for developing stress-tolerant plants. Roots system has a major role in coping with the osmotic change impacted by salinity and few salt-stress-related transcriptome studies in rice have been previously reported. However, transcriptome data sets using rice roots grown in soil condition are more relevant for further applications, but have not yet been available. The present work analyzed rice root and shoot physiological characteristics in response to salt stress using 250 mM NaCl for different timepoints. Subsequently, we identified that 5 day treatment is critical timepoint for stress response in the specific experimental design. We then generated RNA-Seq-based transcriptome data set with rice roots treated with 250 mM NaCl for 5 days along with untreated controls in soil condition using rice japonica cultivar Chilbo. We identified 447 upregulated genes under salt stress with more than fourfold changes (p value < 0.05, FDR < 0.05) and used qRT-PCR for six genes to confirm their salt-dependent induction patterns. GO-enrichment analysis indicated that carbohydrate and amino-acid metabolic process are significantly affected by the salt stress. MapMan overview analysis indicated that secondary metabolite-related genes are induced under salt stress. Metabolites profiling analysis confirmed that phenolics and flavonoids accumulate in root under salt stress. We further constructed a functional network consisting of regulatory genes based on predicted protein–protein interactions, suggesting useful regulatory molecular network for future applications.
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.