Project description:The Manila clam (Ruditapes philippinarum) is the bivalve species with the highest world production from both fisheries and aquaculture, but its production is seriously threatened by perkinsosis, a disease caused by the protozoan parasite Perkinsus olseni. To understand the molecular mechanisms underlying R. philippinarum–P. olseni interaction, we analyzed the gene expression profiles of in vitro challenged clam hemocytes and P. olseni trophozoites, using two oligo-microarray platforms, one previously validated for R. philippinarum hemocytes and a new one developed and validated in this study for P. olseni. Manila clam hemocytes were in vitro challenged with trophozoites, zoospores, and extracellular products from P. olseni in vitro cultures, while P. olseni trophozoites were in vitro challenged with Manila clam plasma along the same time-series (1 h, 8 h, and 24 h). The hemocytes showed a fast activation of the innate immune response, particularly associated with hemocyte recruitment, in the three types of challenges. Nevertheless, different immune-related pathways were activated in response to the different parasite stages, suggesting specific recognition mechanisms. Furthermore, the analyses provided useful complementary data to previous in vivo challenges, and confirmed the potential of some proposed biomarkers. The combined analysis of gene expression in host and parasite identified several processes in both the clam and P. olseni, such as redox and glucose metabolism, protease activity, apoptosis and iron metabolism, whose modulation suggests cross-talk between parasite and host. This information might be critical to determine the outcome of the infection, thus highlighting potential therapeutic targets. Altogether, the results of this study aid to understand the response and interaction between R. philippinarum–P. olseni and will contribute for developing effective control strategies for this threatening parasitosis.
Project description:Blue mussel larvae were fed, in a first group, a balanced diet of essential fatty acids (EFAs) provided by a cocktail diet (COC) from three algal species. Larvae were cultured in three separate tanks from hatching, 0 day post-fertilization (DPF) until 42 DPF. Treated larvae were fed a deficient diet (Tiso) that contains low levels of arachidonic acid (AA) and eicosapentaenoic acid (EPA), two EFAs necessary for larval development, performance, and survival. The goal is to identify coordinated patterns of gene expression and understand their predictive function in relation to growth and mortality during early developmental stages of the blue mussel Mytilus edulis. In order to understand the mechanisms by which growth and survival drive an organism to the full range of its adaptation, we de novo assembled of the mussel transcriptome during early development using next-generation sequencing (NGS) technology, then designed customized microarrays targeting every developmental stage, which encompass major transitions in tissue organization of the fast-evolved blue mussel
Project description:The Manila clam (Ruditapes philippinarum) is the bivalve species with the highest world production from both fisheries and aquaculture, but its production is seriously threatened by perkinsosis, a disease caused by the protozoan parasite Perkinsus olseni. To understand the molecular mechanisms underlying R. philippinarum–P. olseni interaction, we analyzed the gene expression profiles of in vitro challenged clam hemocytes and P. olseni trophozoites, using two oligo-microarray platforms, one previously validated for R. philippinarum hemocytes and a new one developed and validated in this study for P. olseni. Manila clam hemocytes were in vitro challenged with trophozoites, zoospores, and extracellular products from P. olseni in vitro cultures, while P. olseni trophozoites were in vitro challenged with Manila clam plasma along the same time-series (1 h, 8 h, and 24 h). The hemocytes showed a fast activation of the innate immune response, particularly associated with hemocyte recruitment, in the three types of challenges. Nevertheless, different immune-related pathways were activated in response to the different parasite stages, suggesting specific recognition mechanisms. Furthermore, the analyses provided useful complementary data to previous in vivo challenges, and confirmed the potential of some proposed biomarkers. The combined analysis of gene expression in host and parasite identified several processes in both the clam and P. olseni, such as redox and glucose metabolism, protease activity, apoptosis and iron metabolism, whose modulation suggests cross-talk between parasite and host. This information might be critical to determine the outcome of the infection, thus highlighting potential therapeutic targets. Altogether, the results of this study aid to understand the response and interaction between R. philippinarum–P. olseni and will contribute for developing effective control strategies for this threatening parasitosis.
Project description:Transcriptional profiling of populations in the clam Ruditapes decussatus determined differentiation in gene-expression along parallel temperature gradients and between races of the Atlantic Ocean and West Mediterranean sea.
Project description:A zebra mussel byssus cDNA microarray was used to identify the differentially expressed genes between attachment and detachment. Keywords: Gene differential expression
Project description:Blue mussel larvae were fed, in a first group, a balanced diet of essential fatty acids (EFAs) provided by a cocktail diet (COC) from three algal species. Larvae were cultured in three separate tanks from hatching, 0 day post-fertilization (DPF) until 42 DPF. Treated larvae were fed a deficient diet (Tiso) that contains low levels of arachidonic acid (AA) and eicosapentaenoic acid (EPA), two EFAs necessary for larval development, performance, and survival. The goal is to identify coordinated patterns of gene expression and understand their predictive function in relation to growth and mortality during early developmental stages of the blue mussel Mytilus edulis. In order to understand the mechanisms by which growth and survival drive an organism to the full range of its adaptation, we de novo assembled of the mussel transcriptome during early development using next-generation sequencing (NGS) technology, then designed customized microarrays targeting every developmental stage, which encompass major transitions in tissue organization of the fast-evolved blue mussel Two experimental conditions, COC and Tiso diets. Biological replicates 3 culture replicate per stage of development for 5 stages of development. Eggs and trocophore larvae did not undertake treatments
Project description:The Manila clam (Ruditapes philippinarum) is the bivalve species with the highest world production from both fisheries and aquaculture, but its production is seriously threatened by perkinsosis, a disease caused by the protozoan parasite Perkinsus olseni. To understand the molecular mechanisms underlying R. philippinarum–P. olseni interaction, we analyzed the gene expression profiles of in vitro challenged clam hemocytes and P. olseni trophozoites, using two oligo-microarray platforms, one previously validated for R. philippinarum hemocytes and a new one developed and validated in this study for P. olseni. Manila clam hemocytes were in vitro challenged with trophozoites, zoospores, and extracellular products from P. olseni in vitro cultures, while P. olseni trophozoites were in vitro challenged with Manila clam plasma along the same time-series (1 h, 8 h, and 24 h). The hemocytes showed a fast activation of the innate immune response, particularly associated with hemocyte recruitment, in the three types of challenges. Nevertheless, different immune-related pathways were activated in response to the different parasite stages, suggesting specific recognition mechanisms. Furthermore, the analyses provided useful complementary data to previous in vivo challenges, and confirmed the potential of some proposed biomarkers. The combined analysis of gene expression in host and parasite identified several processes in both the clam and P. olseni, such as redox and glucose metabolism, protease activity, apoptosis and iron metabolism, whose modulation suggests cross-talk between parasite and host. This information might be critical to determine the outcome of the infection, thus highlighting potential therapeutic targets. Altogether, the results of this study aid to understand the response and interaction between R. philippinarum–P. olseni and will contribute for developing effective control strategies for this threatening parasitosis.
Project description:Transcriptional profiling of different clam tissues (hemolymph and mantle) in response to QPX disease and temperautre Quahog Parasite Unknown (QPX) is a fatal protistan parasite that causes severe losses in the hard clam (Mercenaria mercenaria) fisheries along the northeastern coast of the US. Field and laboratory studies of QPX disease have demonstrated a major role for water temperature and M. mercenaria genetic origin in disease development. Infections are more likely to occur at cold temperatures, with clam stocks originating from southern states being more susceptible than clams from northern origin where disease is enzootic. Even though the influence of temperature on QPX infection have been examined in susceptible and resistant M. mercenaria at physiological and cellular scales, the underlying molecular mechanisms associated with host-pathogen interactions remain largely unknown. This study was carried out to explore the molecular changes in M. mercenaria in response to temperature and QPX infection on the transcriptomic level, and also to compare molecular responses between susceptible and resistant clam stocks. A M. mercenaria oligoarray (15K Agilent) platform was produced based on our previously generated transcriptomic data and was used to compare gene expression profiles in naive and QPX-infected susceptible (Florida stock) and resistant (Massachusetts) clams maintained at temperatures favoring disease development (13 °C) or clam healing (21 °C). In addition, transcriptomic changes reflecting focal (the site of infection, mantle) and systemic (circulating hemocytes) responses were also assessed using the oligoarray platform. Results revealed significant regulation of multiple biological pathways by temperature and QPX infection, mainly associated with immune recognition, microbial killing, protein synthesis, oxidative protection and metabolism. Alterations were widely systemic with most changes in gene expression revealed in hemocytes, highlighting the role of circulating hemocytes as the first line of defense against pathogenic stress. A large number of complement-related recognition molecules with fibrinogen or C1q domains were shown to be specially induced following QPX challenge, and the expression of these molecules was significantly higher in resistant clams as compared to susceptible ones. These highly variable immune proteins may be potent candidate molecular markers for future study of M. mercenaria resistance against QPX. Beyond the specific case of clam response to QPX, this study also provides insights into the primitive complement-like system in the hard clam. Three-condition interaction experiment (Temperature x clam/infection type x tissue type), 2 temperatures, 3 clam/infection types, 2 tissues, 3 biological replicates for each condition
Project description:Here, we integrated high-throughput transcriptome and proteome sequencing to construct a comprehensive protein database for the byssus of Chinese green mussel (Perna viridis), aiming at providing novel insights into the molecular mechanisms of byssal binding to heavy metals.