Project description:Paulownia elongata is a fast-growing tree species native to China that is grown in different climates, types of soils, and can be easily re-grown. The versatility of the P. elongata species makes it an ideal candidate for biofuel production. High soil salinity is known to inhibit plant growth dramatically or lead to death. Salinity in soil is a detrimental abiotic stress affecting crop production worldwide and a hindrance for potential crop candidates used for biofuel production. The purpose of this study was to characterize the salt-induced transcriptome of P. elongata. Transcriptome differences in response to salt stress were determined by RNA sequencing (RNA-seq) using next generation sequencing and bioinformatics analysis. A total of 646 genes were found to have significant altered expression in response to salt stress, and expression levels of a selective subset of these genes were chosen and confirmed using quantitative real-time PCR. To the best of our knowledge, this is the first report of salt-induced transcriptome analysis in P. elongata. The current study indicates that the differential expression of certain genes may have an important role in the adaptation of P. elongata in response to salt stress. Functional characterization of these genes will assist in future development of salt tolerance in P. elongata, which could be used to enhance biofuel production.
Project description:Populus euphratica is a medium-sized deciduous tree naturally grown in high saline condition, however, the molecular response of the poplar to salinity at global genome level maintain to be elucidated. We used Affymetrix poplar genome microarrays to investigate the full transcript expression exposed to different salt intensities and identified significantly changed transcripts within the 24 hours after exposed to salt stress.
Project description:Enterobacter sp. SA187 is a facultative endophytic bacterium conferring multi-abiotic stress tolerance to various plant hosts. Upon interaction with plant tissues, a significant proportion of the typically yellow SA187 lose pigmentation. This phenotypic shift becomes more prominent with extended host plant colonization and under stress conditions, such as salinity. To explore the underlying mechanisms and ecological significance of this variation, we employed genome sequencing, comparative genomics, transcriptomics, and metabolic characterization. In all white SA187 variants, weidentified consistent point mutations in the rpoS gene, which encodes a global regulatory sigma factor. These rpoS loss-of-function mutations lead to alterations in gene regulation, affecting growth, morphology, biofilm formation, motility, oxidative stress responses and carotenoid production. Notably, the rpoS mutants demonstrated enhanced adaptability from a free living to an endophytic life style. Whereas the desert soil is characterized by highly alkaline conditions, the apoplast of the host plant is an acidic environment accompanied with the availability of distinct carbon sources. RpoS mutants allow life in the acidic and sucrose-rich apoplastic compartment, underscoring the role of genetic variation in bacterial adaptation to colonize plants.
Project description:The fate of the carbon stocked in permafrost soils following global warming and permafrost thaw is of major concern in view of the potential for increased CH4 and CO2 emissions from these soils. Complex carbon compound degradation and greenhouse gas emissions are due to soil microbial communities, but their composition and functional potential in permafrost soils are largely unknown. Here, a 2 m deep permafrost and its overlying active layer soil were subjected to metagenome sequencing, quantitative PCR, and microarray analyses. The active layer soil and 2 m permafrost soil microbial community structures were very similar, with Actinobacteria being the dominant phylum. The two soils also possessed a highly similar spectrum of functional genes, especially when compared to other already published metagenomes. Key genes related to methane generation, methane oxidation and organic matter degradation were highly diverse for both soils in the metagenomic libraries and some (e.g. pmoA) showed relatively high abundance in qPCR assays. Genes related to nitrogen fixation and ammonia oxidation, which could have important roles following climatic change in these nitrogen-limited environments, showed low diversity but high abundance. The 2 m permafrost soil showed lower abundance and diversity for all the assessed genes and taxa. Experimental biases were also evaluated and showed that the whole community genome amplification technique used caused large representational biases in the metagenomic libraries. This study described for the first time the detailed functional potential of permafrost-affected soils and detected several genes and microorganisms that could have crucial importance following permafrost thaw. A 2m deep permafrost sample and it overlying active layer were sampled and their metagenome analysed. For microarray analyses, 8 other soil samples from the same region were used for comparison purposes.
Project description:Few aerobic hyperthermophiles degrade polysaccharides. We describe the genome-enabled enrichment and isolation of an aerobic hyperthermophile, Fervidibacter sacchari, which was originally ascribed to candidate phylum Fervidibacteria. F. sacchari uses polysaccharides and monosaccharides as sole carbon sources from 65-87.5 °C, and its genome encodes 117 glycoside hydrolases (GHs) spanning 49 GH families, including 31 homologs of understudied GH109, GH177, and GH179 domains. Here, we analyzed the transcriptomes of F. sacchari cells grown on eight different sole carbon and energy sources (beta-glucan, chondroitin sulfate, corn stover, gellan gum, locust bean gum, starch, xanthan gum, and xyloglucan) to link glycoside hydrolase substrate to function, as well as identify potential regulatory mechanisms. These data will provide preliminary characterization of novel carbohydrate-active enzymes at high temperatures.
Project description:The fate of the carbon stocked in permafrost soils following global warming and permafrost thaw is of major concern in view of the potential for increased CH4 and CO2 emissions from these soils. Complex carbon compound degradation and greenhouse gas emissions are due to soil microbial communities, but their composition and functional potential in permafrost soils are largely unknown. Here, a 2 m deep permafrost and its overlying active layer soil were subjected to metagenome sequencing, quantitative PCR, and microarray analyses. The active layer soil and 2 m permafrost soil microbial community structures were very similar, with Actinobacteria being the dominant phylum. The two soils also possessed a highly similar spectrum of functional genes, especially when compared to other already published metagenomes. Key genes related to methane generation, methane oxidation and organic matter degradation were highly diverse for both soils in the metagenomic libraries and some (e.g. pmoA) showed relatively high abundance in qPCR assays. Genes related to nitrogen fixation and ammonia oxidation, which could have important roles following climatic change in these nitrogen-limited environments, showed low diversity but high abundance. The 2 m permafrost soil showed lower abundance and diversity for all the assessed genes and taxa. Experimental biases were also evaluated and showed that the whole community genome amplification technique used caused large representational biases in the metagenomic libraries. This study described for the first time the detailed functional potential of permafrost-affected soils and detected several genes and microorganisms that could have crucial importance following permafrost thaw.
Project description:Soybean's productivity is significantly compromised by soil salinity, but, like most plants, it has evolved a variety of mechanisms to aid its survival under environmental stress. The expression of many plant genes is altered by salinity stress. We used microarrays to detail the global programme of gene expression and identified distinct up or down-regulated genes between salinity stressed and non stressed soybean
Project description:Soybean's productivity is significantly compromised by soil salinity, but, like most plants, it has evolved a variety of mechanisms to aid its survival under environmental stress. The expression of many plant genes is altered by salinity stress. We used microarrays to detail the global programme of gene expression and identified distinct up or down-regulated genes between salinity stressed and non stressed soybean Seedlings of the soybean cultivar Williams 82 were grown in vermiculite under a 16h photoperiod at 25 ºC for 14 days. RNA were isolated from the mock (M0, M1, M3, M6, M12, M24) and salinity treated (S0, S1, S3, S6, S12, S24) seedlings. 0.5 µg RNA that extracted from each time point of the mock and salinity-stressed seedlings were mixed respectively to obtain the mock and salinity-stressed RNA pools, and then they were used to synthesize the cDNA. The cDNA was labeled with biotin, and then hybridized to an Affymetrix soybean Genome Array.
Project description:Fervidibacter sacchari PD1 cells were grown with beta-glucan, gellan gum, locust bean gum, starch, or xyloglucan as sole carbon/energy sources. Cellular and secreted proteins under each condition were analyzed with DIA proteomics.
Project description:Gene expression patterns in roots of Camelina sativa with enhanced salinity tolerance arising from growth in soil treated with plant growth promoting bacteria producing 1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase) or from expression of the corresponding acdS gene in transgenic lines. Salinity stress negatively affects crop production. However in camelina, grown in soils treated with PGPB producing 1-aminocyclopropane-1-carboxylate deaminase (acdS ) or transgenic lines expressing acdS exhibited increased salinity tolerance. AcdS reducing the level of stress ethylene to below the point where it is inhibitory to growth. Gene expression patterns in roots responding to salt stress was affected by the expression of acdS under the control of CaMV 35S or root-specific (rolD) promoters in transgenic lines, or by growth in soils treated with endophytic PGPB producing acdS indicate that the number of the genes were differentially expressed were more assigned to genome III in transgenic plants however in PGPB treated plants the number of the genes were differentially expressed were almost equally assigned to all three genomes. Different promoter may induce different set or even different homeologues genes in camelina with probably the same function in response to salt stress. Though root is not a photosynthetic tissue reduction of the ethylene in root cells has positive effect on plant photosynthetic machinery. The expression of the genes involved in minor CHO metabolism was up-regulated mainly in roots of acdS contain plants during salt stress. Moderate reduction in ethylene production has positive effect on root growth during salt stress but reduction of the ethylene higher than a certain level has negative effect on root growth due to reduction of the expression of the genes involved in root cell elongation. AcdS gene modulating the level of ROS in cells in the level that induce ROS signaling but preventing cellular damage by make a balance on up and down-regulation of the genes involved in oxidation-reduction process in root cells under salinity stress. The acdS containing PGPB (8R6) were mostly effected the ethylene signaling and ABA biosynthesis and signaling in positive way but transgenic line depends to the promoter affecting Auxin, JA and BR signaling or biosynthesis.