Project description:In order to reveal so far unknown facets of the adaptation of B. subtilis to growth under high-salinity conditions, a whole-transcriptome analysis of B. subtilis BSB (168 Trp+) was performed using strand-specific tiling arrays (tiling step of 22 nucleotides). In addition, the effects of glycine betaine (GB) were analyzed under high salinity and standard growth conditions in a chemically defined medium. Important novel findings were a sustained low-level induction of the SigB-dependent general stress response and strong repression of biofilm matrix genes under high-salinity conditions. GB influences gene expression not only under high-salinity, but also under standard growth conditions without additional salt.
Project description:Sea cucumber, Apostichopus japonicus is a very important species for aquaculture, and its behavior and physiology can respond to the initial change in salinity. It is important to understand the molecular responses of A. japonicus when exposed to ambient changes in salinity In this study, RNA-seq provided a general overview of the gene expression profiles of the intestine of A. japonicus exposed to high salinity (SD40), normal salinity (SD30) and low salinity (SD20) environment.
Project description:Three rice major tissues, namely flag leaf, shoot and panicle, were involved in this study. Each tissue had two kinds stress treatment, drought and high salinity, in 3 different time courses. For drought treated samples, an additional water recovery was applied. Each experiment had three replicates. Keywords: Comparison of gene expression in three tissues with stress treatment and without treatment To globally elucidate potential genes involved in drought and high-salinity stresses responses in rice, an oligomer microarray covering 37,132 genes including cDNA or EST supported and putative genes was applied to study the expression profiling of shoot, flag leaf, and panicle under drought or high-salinity treatment. Three rice major tissues, namely flag leaf, shoot and panicle, were involved in this study. Each tissue had two kinds stress treatment, drought and high salinity, in 3 different time courses. For drought treated samples, an additional water recovery was applied. Each experiment had three replicates.
Project description:Thermophilic fungi are eukaryotic species that grow at high temperatures, but little is known about the thermophily of thermophilic fungi. Here the proteome and N-glycoproteome of Chaetomium thermophilum at varying culture temperatures (30℃, 50℃, and 55℃) were studied using hydrophilic interaction liquid chromatography enrichment and high-resolution liquid chromatography–tandem mass spectroscopy analysis. In proteome, the numbers of differentially expressed proteins were 1274, 1374, and 1063 in T50/T30, T55/T30, and T55/T50, respectively. The up-regulated proteins were involved in biological processes, such as protein folding and carbohydrate metabolism. Most down-regulated proteins were involved in molecular functions, such as structural constituent of the ribosome and structural activity. For N-glycoproteome, the numbers of differentially expressed N-glycoproteins were 160, 176, and 128 in T50/T30, T55/T30, and T55/T50, respectively. The differential glycoproteins were mainly involved in various types of N-glycan biosynthesis, mRNA surveillance pathway, and protein processing in the endoplasmic reticulum. These results indicated that an efficient protein homeostasis pathway plays an essential role in the thermophily of C. thermophilum, and N-glycosylation is involved by affecting related proteins. This is the first study to reveal thermophilic fungi's physiological response to high-temperature adaptation using omics analysis, facilitating the exploration of the thermophily mechanism of thermophilic fungi.
Project description:‘Pulsechip’, a boutique cDNA microarray, generated from a set of chickpea (Cicer arietinum L.) unigenes, grasspea (Lathyrus sativus L.) ESTs and lentil (Lens culinaris Med.) resistance gene analogs, was employed to generate an expression profile of chickpea accessions tolerant and susceptible to high-salinity stress. Two groups of a tolerant and susceptible accession were challenged with high-salinity stress. The experiments were performed in three biological replications. The experiments were conducted in reference design where respective tissues from unstressed plants served as control. The leaf/shoot and root tissues were collected at 24 and 48 h post-treatment (hpt) and used for hybridization to measure changes in RNA abundance of treatment vs. control. The tissues from five experimental replicate plants per biological replication were pooled together (shoot and root tissues separate for each time point) before RNA extraction. This RNA was used to prepare cDNA targets for expression analysis using microarray. The microarray had six technical replicate spots per EST. The transcript level for each EST/cDNA was firstly calculated as the average intensity of the six technical replicates and then the average intensity of three biological replicates. Data analysis included LOWESS normalization (LOcally WEighted polynomial regreSSion) to adjust for differences in quantity of initial RNA, labeling and detection efficiencies. A dye swap in one biological replicate adjusted dye bias, if any. The Differentially Expressed (DE) ESTs were identified as those with a 95% confidence interval for mean fold change (FC) that extended beyond the two-fold cut-off and also passed the Students t test (P<0.05) and FDR correction. These cut-offs translate into induced ESTs having a log2 ratio > 1 and repressed ESTs a ratio of < -1. The analysis consisted of three fold comparison. Firstly, the ESTs that were differentially expressed between treatment and control plants of each accession were detected. Then the ESTs that were similarly expressed by tolerant and susceptible accessions were then eliminated by comparison. This included a two-way comparison, where tolerant and susceptible genotypes were compared within and between groups. Lastly, ESTs that were consensually differentially expressed between tolerant and susceptible accessions of the two batches were identified. The hypothesis was that if a putative gene was consistently expressed only in tolerant or susceptible genotype for a particular stress, it might be a candidate for tolerance/susceptibility for that stress. Globally, the level of 409 transcripts was affected in response to high-salinity stress in all the genotypes and tissue types studied. Of the transcripts consistently expressed in tolerant genotypes in response to high-salinity stress, the annotation of transcripts at 24 hpt suggest a reduction in energy production in shoots and roots by repression of putative genes including P700 chlorophyll a-apoprotein (DY475501) and NADH-plastoquinone oxidoreductase subunit I (DY475287), cytosolic fructose 1,6-bisphosphatase (DY475548) and splicing factor-like protein (DY396290). The ATHP3 (DY396300) and protein kinase (DY475077) that are potentially involved in signalling cascades responsible for sensing and relaying osmotic stress signals, were consistently repressed in tolerant genotypes in response to high-salinity. Additionally a glycine rich protein (DY396342) that is associated with lignification of cell walls in response to wounding and pathogen attack was repressed in tolerant genotypes. In tolerant genotypes at 48 hpt, two energy and metabolic-related transcripts were consistently repressed in roots, including a carbonic anhydrase (DY475403) and putative thiazole biosynthetic enzyme (DY475242). In shoots, only a pathogenesis-related protein (DY396301) was consistently repressed at 48 hpt, but a similar transcript (DY396281) was induced in roots of tolerant genotypes at the same time. Only four transcripts were DE in susceptible genotypes at 24 hpt, all occurring in root tissue. Two of these were unknown/unclear, but the others included a proline oxidase transcript (DY475225) and a nuclear transport factor 2 (DY396436). At 48 hpi, a putative splicing factor-like protein (DY396290) and polyubiquitin (DY396328) were repressed in roots of susceptible genotypes. Interstingly, a putative xylosidase (DY475408) was induced in susceptible roots at 48 hpi. Finally, several unknown/unclear transcripts were DE in both tolerant and susceptible genotypes. Of interest were two unknowns (DY475293 and DY475521) that were consistently expressed in tolerant genotypes and may be important for high-salinity tolerance. Keywords: Chickpea, High-salinity stress, tolerant, susceptible, cDNA microarray
Project description:We applied the tiling arrays to study the Arabidopsis whole-genome transcriptome under drought, cold, high-salinity and ABA treatment conditions and idenfied many stress- or ABA- responsive putative functional RNAs and fully-overlapping sense-antisense transcripts in Arabidopsis genome. Keywords: stress response
Project description:In low rainfall regions soils are naturally conditioned with frequent co-occurrence of salinity and alkalinity. Plant salinity responses both at physiological and molecular level have been extensively researched. However, effects of the combined treatment of alkaline salinity that could greatly reduce plant growth and the mechanisms responsible for tolerance remain indeterminate. In Brassica juncea, large reductions in biomass and increased leaf Na+ concentration under alkaline salinity indicates that the combined treatment had greater negative effect than salinity on both growth and the physiological responses of the plant. To determine molecular mechanisms potentially controlling adaptive tolerance responses to salinity and alkaline salinity, the moderately tolerant genotype NDR 8501 was further investigated using microarray analysis. The transcripts of treated leaf tissues verses those of the untreated control sample were analysed after prolonged stress of four weeks. In total, 528 salinity responsive and 1245 alkaline salinity responsive genes were indentified and only 101 genes were expressed jointly in either of the two treatments. Transcription of 37% more genes involved in response to alkaline salinity than salinity alone, which suggests the increased impact and severity of the combined stress on the plant, indicating the transcription of a far greater number of genes likely involved in mitigation and damage control. Transcription of KUP2 and KUP7 genes involved in potassium homeostasis under salinity alone and NHX1 and ENH1 genes for ion (K+ and Na+) homeostasis under alkaline salinity, clearly demonstrated that different genes and genetic pathways are involved in response to each stress. They further provide supporting evidence for the physiological responses that occur in the plant, with massive reprogramming of the transcriptome leading to partial ion exclusion, shuttling and compartmentation.
Project description:The zygomycete fungi-like Rhizomucor miehei have been extensively exploited for the production of various enzymes. As a thermophilic fungus, R. miehei is capable of growing at temperatures that approach the upper limits for all eukaryotes. In order to study the thermophilic mechanism, the transcriptional profiles of R. miehei CAU432 grown at two different temperatures (at 30°C and 50°C) were investigated by RNA-seq analysis. Approximately 35 million high-quality reads were generated from each library, and 62% reads were uniquely mapped to the genome. A high percentage of reads (67.1%) were mapped to predicted protein-coding genes, while 3.96% reads were distributed in splice junctions, 3.49% reads in antisense transcripts, 2.27% in introns, and 21.9% in other genomic regions. The frequency of reads which mapped to different genes ranged from one to over 300,000. More than 90% of predicted genes (9,680, 93% at 30°C; 9,618, 93.6% at 50°C) were detected with at least one read, while 128 genes and 190 genes were uniquely expressed at 50°C and 30°C, respectively. The results show that 2,117 genes were differently expressed (P<0.001) by the fungus with more than two-fold changes. These genes include 849 up-regulated and 1,268 down-regulated genes in mycelia grown at 50°C. These significantly differently expressed genes include many genes, putatively involved in thermophilic process, such as HSP, chaperones and proteasome.