Project description:As representatives of n-6 and n-3 fatty acids, many studies have analyzed the use of soybean oil and linseed oil rich in linoleic acid (18:2n-6, LA) and α-linolenic acid (18:3n-3, LNA) as better substitutes for fish oil. In aquatic animals, different dietary ratios of LA and LNA could have significant effects on growth, lipid metabolism, immune response, and reproduction. To assess the nutritive value of these two fatty acids for the Chinese mitten crab (Eriocheir sinensis), we performed transcriptome analysis and proteomic analysis using label-free quantification of the hepatopancreas of mitten crabs fed with LA or LNA diet. Our results provide new insights for further investigation into the replacement of fish oil from mitten crabs with vegetable oils and enable us to better understand the different roles and nutrition value of LA and LNA in mitten crabs.
Project description:Purpose:The mud crab Scylla paramamosain is an economically important marine crab in China suffering from severe outbreaks of infectious disease caused by marine bacteria such as Vibrio Parahaemolyticus, resulting in great economic losses. However, the mechanisms involved in the immune response of this crab to bacterial infection are not fully understood. To understand the molecular mechanisms underlying the immune response to such pathogenic bacteria, we used high-throughput deep sequencing technology to investigate the transcriptome and comparative expression profiles of the mud crab S.paramamosain infected with V.parahaemolyticus. Methods: The hemocytes sampled at 0-24h after infection with V.parahaemolyticus were used for transcriptome analysis. The hemocytes sampled at 24 h after injections with V.parahaemolyticus and no injected 0h(as control) were used for gene expression profiling analysis. Results: A total of 52,934,042 reads were obtained and assembled into 186,193 contigs in transcriptional responses of the V.parahaemolyticus-infected mud crab. Via annotation to the NCBI database and the Swissprot database, we obtained 48,934 identified unigenes. In total, 10,139(20.7%) unigenes were classified into Gene Ontology, and 25,349 unigenes were found in 20 KEGG categories. These genes included representatives from almost all functional categories. By using Solexa/Illumina's DeepSAGE, 1213 differentially expressed genes (P value < 0.05) were detected in comparative analysis of the expression profiles between V.parahaemolyticus-infected crabs and control crabs, including 538 remarkably upregulated genes and 675 remarkably downregulated genes. Conclusions: Based on our results, we conclude that the inflammatory response may play an important role in the early stages of infection. The signaling cascades such as the chemokine, JAK-STAT, and MAPK pathways are regulated by V.parahaemolyticus infection. These results revealed changes of multiple signaling pathways involved in immunity during V.parahaemolyticus infection, which will facilitate our comprehensive understanding of the mechanisms involved in the immune response to bacterial infection in the mud crab.
Project description:Intertidal zone organisms can experience transient freezing temperatures during winter low tides, but their extreme cold tolerance mechanisms are not known. Petrolisthes cinctipes is a temperate mid-high intertidal zone crab species that can experience wintertime habitat temperatures below the freezing point of seawater. We examined how cold tolerance changed during the initial phase of thermal acclimation to cold and warm temperatures, as well as the persistence of cold tolerance during long-term thermal acclimation. Thermal acclimation for as little as 6 hours at 8˚C enhanced crab tolerance during a 1h exposure to -2°C relative to crabs acclimated to 18˚C. Potential mechanisms for this enhanced tolerance were elucidated using cDNA microarrays to probe for differences in gene expression in cardiac tissue of warm and cold acclimated crabs during the first day of thermal acclimation. No changes in gene expression were detected until 12h of thermal acclimation. Genes strongly upregulated in warm acclimated crabs represented immune response and extracellular / intercellular processes, suggesting that warm acclimated crabs had a generalized stress response and may have been remodelling tissues or altering intercellular processes. Genes strongly upregulated in cold acclimated crabs included many that are involved in glucose production suggesting that cold acclimation involves increasing intracellular glucose as a cryoprotectant. Structural cytoskeletal proteins were also strongly represented among the genes upregulated in only cold acclimated crabs. There were no consistent changes in composition or the level of unsaturation of membrane phospholipid fatty acids with cold acclimation, which suggests that neither short- nor long-term changes in cold tolerance are mediated by changes in membrane fatty acid composition. Overall, our study demonstrates that initial changes in cold tolerance are likely not regulated by transcriptomic responses, but that gene expression-related changes in homeostasis begin within 12 hours – the length of a tidal cycle. all array data and raw images archived at the Porcelain Crab Array Database (http://array.sfsu.edu)
Project description:Intertidal zone organisms can experience transient freezing temperatures during winter low tides, but their extreme cold tolerance mechanisms are not known. Petrolisthes cinctipes is a temperate mid-high intertidal zone crab species that can experience wintertime habitat temperatures below the freezing point of seawater. We examined how cold tolerance changed during the initial phase of thermal acclimation to cold and warm temperatures, as well as the persistence of cold tolerance during long-term thermal acclimation. Thermal acclimation for as little as 6 hours at 8˚C enhanced crab tolerance during a 1h exposure to -2°C relative to crabs acclimated to 18˚C. Potential mechanisms for this enhanced tolerance were elucidated using cDNA microarrays to probe for differences in gene expression in cardiac tissue of warm and cold acclimated crabs during the first day of thermal acclimation. No changes in gene expression were detected until 12h of thermal acclimation. Genes strongly upregulated in warm acclimated crabs represented immune response and extracellular / intercellular processes, suggesting that warm acclimated crabs had a generalized stress response and may have been remodelling tissues or altering intercellular processes. Genes strongly upregulated in cold acclimated crabs included many that are involved in glucose production suggesting that cold acclimation involves increasing intracellular glucose as a cryoprotectant. Structural cytoskeletal proteins were also strongly represented among the genes upregulated in only cold acclimated crabs. There were no consistent changes in composition or the level of unsaturation of membrane phospholipid fatty acids with cold acclimation, which suggests that neither short- nor long-term changes in cold tolerance are mediated by changes in membrane fatty acid composition. Overall, our study demonstrates that initial changes in cold tolerance are likely not regulated by transcriptomic responses, but that gene expression-related changes in homeostasis begin within 12 hours – the length of a tidal cycle. all array data and raw images archived at the Porcelain Crab Array Database (http://array.sfsu.edu) n=264 specimens were divided into warm (18°C, n=96), cold (8°C, n=96), and control (13°C, n=72) acclimation groups. Crabs were sampled from the 13°C group at 0 h (the start of the experiment) and 24 h, the termination of the experiment. Crabs were sampled from the warm and cold acclimation groups at 6, 12, 18, and 24 hours following the start of thermal acclimation. At each time point, heart tissue from n=16 crabs from each group was dissected, flash frozen and stored at −80°C. A pooled total aRNA sample was prepared for each group by mixing equal quantities of total RNA from n=5 individuals in each group in order to have the same amount of biological diversity within each pooled RNA sample. For microarray hybridizations we used n=25 slides in an incomplete loop design where each sample was hybridized n=5 times, 2-3 times labelled with each Cy dye
Project description:In juvenile Chinese mitten crabs, Eriocheir sinensis, the occurrence of sexual gland maturation in the first year is known as precocity and significantly affects culture productivity and profitability. The miniaturization of individuals is a key characteristic of precocious crabs. Most related studies focus on the underlying causes, nutritional quality, biochemical components and differentially expressed mRNAs of precocious crab individuals and tissues. The reproductive performance of precocious crabs is evaluated based on offspring quality. However, the status of precocious parental gametes (especially spermatozoa) directly related to the offspring has not been reported. To clarify the differences in spermatozoa between precocious and normal mature crabs, spermatozoal proteome data was obtained via high-throughput sequencing technology. The results revealed a total of 856 differentially expressed genes and 150 differentially expressed proteins in spermatozoa. Functional analysis showed that these genes and proteins identified in the spermatozoa of precocious E. sinensis were significantly enriched in the categories of substance and energy metabolism. And more, the miniaturization of spermatogenic cells was also identified in precocious crabs. This indicates that metabolic disorders might be the main reason for the miniaturization of spermatogenic cells in precocious E. sinensis males. The molecular defects in precocious sperm were closely related to the imbalances in essential substance and energy metabolism. These findings provide foundational information and insights into hidden biological irregularities associated with precocious phenotypes and will contribute to the further study of precocious E. sinensis males and even other crustaceans.
Project description:In order to promote our understanding of the responses of green crab acid-base regulatory epithelia to high pCO2, Baltic Sea green crabs were exposed to a pCO2 of 400 Pa for 3 and 7 days after which posterior gills 7 and 9 were sampled. Gills were then subsequently screened for differentially expressed gene transcripts using a 4,462-feature microarray developed by Towle et al. 2010.
Project description:Comparative proteomics elucidates the potential mechanism of heritable carapace color of three strains Chinese mitten crab Eriocheir sinensis