Project description:In this study, RNA-Seq was used to reveal the differences of molecular pathways in hepatopancreas of O. niloticus adapated to water with salinity of 8 or 16 practical salinity (psu), respectively, with fish at freshwater as the control,. Significantly changed pathways were mainly related to lipid metabolism, glucose utilization, protein consumption, osmotic regulation, signal transduction and immunology. Based on the tendencies from freshwater to 8 or 16 psu, the differentially expressed gene unions were categorized into eight unique models, which were further classified into three categories which were constant-change (either keep increasing or decreasing), change-then-stable and stable-then-change. In constant-change category, steroid biosynthesis, steroid hormone biosynthesis, fat digestion and absorption, complement and coagulation cascades were extremely significantly affected by ambient salinity (P < 0.01), indicating that these pathways play pivotal roles in molecular response to salinity acclimation from freshwater to saline water in O. niloticus, and should be the main research focus in the future. In change-then-stable category, ribosome, oxidative phosphorylation, peroxisome proliferator-activated receptors (PPAR) signaling pathway, fat digestion and absorption changed significantly with ambient increasing salinity (P < 0.01), showing these pathways were sensitive to environmental salinity variation, but had a response threshold, and would stop changing once salinity exceeds the threshold. In stable-then-change category, protein export, protein processing in endoplasmic reticulum, tight junction, thyroid hormone synthesis, antigen processing and presentation, glycolysis/gluconeogenesis and glycosaminoglycan biosynthesis - keratan sulfate were the top changed pathways (P < 0.01), suggesting that these pathways were not sensitive to salinity variation, but these pathways will respond significantly under salinity exceeding a certain level. The pathways and genes reported in this study laid on a solid foundation for future studies in understanding the underlying mechanism for salinity adaptation of freshwater fish. Examination of 3 different salinities treated hepatopancreas in Nile tilapia
Project description:In this study, RNA-Seq was used to reveal the differences of molecular pathways in hepatopancreas of O. niloticus adapated to water with salinity of 8 or 16 practical salinity (psu), respectively, with fish at freshwater as the control,. Significantly changed pathways were mainly related to lipid metabolism, glucose utilization, protein consumption, osmotic regulation, signal transduction and immunology. Based on the tendencies from freshwater to 8 or 16 psu, the differentially expressed gene unions were categorized into eight unique models, which were further classified into three categories which were constant-change (either keep increasing or decreasing), change-then-stable and stable-then-change. In constant-change category, steroid biosynthesis, steroid hormone biosynthesis, fat digestion and absorption, complement and coagulation cascades were extremely significantly affected by ambient salinity (P < 0.01), indicating that these pathways play pivotal roles in molecular response to salinity acclimation from freshwater to saline water in O. niloticus, and should be the main research focus in the future. In change-then-stable category, ribosome, oxidative phosphorylation, peroxisome proliferator-activated receptors (PPAR) signaling pathway, fat digestion and absorption changed significantly with ambient increasing salinity (P < 0.01), showing these pathways were sensitive to environmental salinity variation, but had a response threshold, and would stop changing once salinity exceeds the threshold. In stable-then-change category, protein export, protein processing in endoplasmic reticulum, tight junction, thyroid hormone synthesis, antigen processing and presentation, glycolysis/gluconeogenesis and glycosaminoglycan biosynthesis - keratan sulfate were the top changed pathways (P < 0.01), suggesting that these pathways were not sensitive to salinity variation, but these pathways will respond significantly under salinity exceeding a certain level. The pathways and genes reported in this study laid on a solid foundation for future studies in understanding the underlying mechanism for salinity adaptation of freshwater fish.
Project description:Low salinity is one of the main factors limiting the distribution and survival of marine species. As a euryhaline species, the Pacific oyster Crassostrea gigas can be tolerant to relative low salinity. Through Illumina sequencing, we generated two transcriptomes with samples taken from gills of oysters exposed to the low salinity seawater versus the optimal seawater. By RNAseq technology, we found 1665 up-regulation genes and 1815 down-regulation genes that may regulate osmotic stress in C. gigas. As blasted by GO annotation and KEGG pathway mapping, functional annotation of the genes recovered diverse biological functions and processes. The genes regulated significantly were dominated in cellular process and regulation of biological process, intracellular and cell, binding and protein binding according to GO annotation. The results highlight genes related to osmoregulation and signaling and interactions of osmotic stress response, anti-apoptotic reactions as well as immune response, cell adhesion and communication, cytosqueleton and cell cycle. The study aimed to compare the expression data of the two transcriptomes to provide some useful insights into signal transduction pathways in oysters and offer a number of candidate genes as potential markers of tolerance to hypoosmotic stress for oysters. In addition, the characterization of C. gigas transcriptome will facilitate research into biological processes underlying physiological adaptations to hypoosmotic shock for marine invertebrates. Twelve Pacific oysters were exposed in low salinity (8‰) seawater and in optimal salinity (25‰) seawater, respectively. Gills from six oysters in each condition were balanced mixed respectively. The transcriptomes of two samples were generated by deep sequencing, using Illumina HiSeq2000.
Project description:Low salinity is one of the main factors limiting the distribution and survival of marine species. As estuarine species, Crassostrea hongkongensis can live in relative low salinity. Through Illumina sequencing, we generated two transcriptomes with samples taken from gills of oysters exposed to the low salinity seawater versus the optimal seawater. By RNAseq technology, we found 13550 up-regulation genes and 9914 down-regulation genes that may regulate osmotic stress in C. hongkongensis. As blasted by GO annotation and KEGG pathway mapping, functional annotation of the genes recovered diverse biological functions and processes. The genes regulated significantly were dominated in structural molecule activity, intracellular,cytoplasm protein metabolism, biosynthesis,cell and transcription regulator activity according to GO annotation. The study aimed to compare the expression data of the two transcriptomes to provide some useful insights into signal transduction pathways in oysters and offer a number of candidate genes as potential markers of tolerance to hypoosmotic stress for oysters. In addition, the characterization of C. hongkongensis transcriptome will facilitate research into biological processes underlying physiological adaptations to hypoosmotic shock for marine invertebrates. Twelve oysters were exposed in low salinity (8‰) seawater and in optimal salinity (25‰) seawater,respectively. Gills from six oysters in each condition were balanced mixed respectively. The transcriptomes of two samples were generated by deep sequencing, using Illumina HiSeq2000
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:In the present study, we compared transcriptional response to salinity between male and female individuals of Populus yunnanensis. We found that several functional groups of genes involved in important pathways were differentially expressed, including photosynthesis-related genes which were mainly up-regulated in males but down-regulated in females. This gene expression pattern is consistent with physiological observation that salinity inhibited photosynthetic capacity more in females than in males. In conclusion, our study provided molecular evidence of sexual differences in poplar salinity tolerance. Identified sex-related genes in salinity tolerance and their functional groups will enhance our understanding of sexual differences to salinity stress at the transcription level.