Project description:This SuperSeries is composed of the following subset Series: GSE22915: Mussel (Mytilus galloprovincialis) digestive gland tissue: gene expression profiles across an annual cycle GSE23049: Mytilus galloprovincialis: development of female gonads GSE23050: Mytilus galloprovincialis: development of male gonads GSE23051: Mytilus galloprovincialis: differences between male and female gene expression patterns in gonads (mantle tissue) Refer to individual Series
Project description:Proteomics to decipher the cocktail effects of three pharmaceuticals (diclofenac, carbamazepine and venlafaxine) as a mixture on the digestive gland of male mussels Mytilus galloprovincialis.
Project description:Transcriptional profiling of the digestive gland tissue of female mussel Mytilus galloprovincialis exposed to TCDD, n-TiO2 and their binary mixture Background: Exposure of marine organisms to pollutant mixtures may affect the pattern of contaminant uptake/bioaccumulation, as well as of gene expression in the tissues. Despite the growing concern over the potential biological impact of nanoparticles (NPs) in the aquatic environment, little is known about their interactions with other pollutants.We have recently shown that in the marine mussel Mytilus galloprovincialis exposure to n-TiO2, one of the most widespread type of NPs in use, in combination with 2,3,7,8-TCDD, chosen as model organic xenobiotic, can exert antagonistic or synergistic effects on different biomarkers from the molecular to the tissue level, depending on cell/tissue and type of measured response. An integrated approach involving immunhistochemical and transcriptomic analysis was employed to clarify the itteractive effects of n-TiO2 and TCDD in mussels digestive gland. In particular,TCDD bioaccumulation was evaluated utilizing specific anti-TCDD fluorescent antibodies. Moreover, immunohistochemical evaluation of antioxidant and cytoskeletal components was performed. To provide clues about how the molecular response to the investigated compounds is modulated, we used a cDNA microarray with1673 sequences. In animals exposed only to TiO2, functional genomics analysis of the microarray data (48 differentially expressed genes (DEGs)) highlighted three biological processes, largely dominated by the up-regulation of microtubule-based movement-related genes. Exposure to 2,3,7,8-TCDD yielded 49 DEGs exhibiting distinct patterns in terms of biological processes. Finally, exposure to the mixture rendered 62 GEGs characterized by the regulation of response to chemical stimulus, microtubule-based movement and intracellular signal transduction. Our data should be carefully considered in view of the biological effects of emerging pollutants, particularly in case of mixture chemicals. Transcriptional profiling of the digestive gland tissue of female mussel Mytilus galloprovincialis exposed to TCDD, n-TiO2 and their binary mixture
Project description:Mussels (Mytilus galloprovincialis) were exposed during 7 and 28 days in seawater (control), seawater + acetone (solvent control, SC), and 10 micrograms per Litre of tris(1,3-dichloro-2-propyl) phosphate (TDCPP). TDCPP was added from a stock solution prepared in acetone, the volume added being 100 µL per 30 L aquaria. The same volume of acetone was added to SC aquaria. Mussel density was 20 mussels per each 30 L aquaria at the beginning of the experiment and varied between 15 ‒ 20 mussels/30 L aquaria during the 28 days exposure period. Exposure conditions were the following: T = 15.6 ± 0.7 ºC, S = 35.5 ± 0.5 ppt, pH = 7.9 ± 0.1, O2 = 7.9 ± 0.6 mg L-1 and 10:14h light:dark photoperiod. Water was renewed twice per week and mussels were fed before every water renewal with a mixture of phytoplankton representing 1% of mussel tissue dry weight.
Project description:The invasive marine mussel Mytilus galloprovincialis has displaced the native congener Mytilus trossulus from central and southern California, but the native species remains dominant at more northerly sites that have high levels of freshwater input. To determine the extent to which interspecific differences in physiological tolerance to low salinity might explain limits to the invasive species’ biogeography, we used an oligonucleotide microarray to compare the transcriptional responses of these two species to an acute decrease in salinity. Among 6,777 genes on the microarray, 117 genes showed significant changes that were similar between species, and 12 genes showed significant species-specific responses to salinity stress. Osmoregulation and cell cycle control were important aspects of the shared transcriptomic response to salinity stress, whereas the genes with species-specific expression patterns were involved in mRNA splicing, polyamine synthesis, exocytosis, translation, cell adhesion, and cell signaling. Forty-five genes that changed expression significantly during salinity stress also changed expression during heat stress, but the direction of change in expression was typically opposite for the two forms of stress. These results (i) provide insights into the role of changes in gene expression in establishing physiological tolerance to acute decreases in salinity, and (ii) indicate that transcriptomic differences between M. galloprovincialis and M. trossulus in response to salinity stress are subtle and involve only a minor fraction of the overall suite of gene regulatory responses. Two species (Mytilus galloprovincialis, Mytilus trossulus), hypo-osmotic shock for four hours (850 mOs/kg), one control group (1000 mOs/kg) sampled at the end of the treatment exposure (850 mOs/kg), one control group (1000 mOs/kg) sampled at the beginning. Biological replicates: 6 in each treatment group, 6 in each control group. Heterologous and homologous hybridization to a microarray constructed from Mytilus californianus and Mytilus galloprovincialis sequences. A reference design that used separate pools of reference RNA for each species was employed. Reference amplified RNA (aRNA) was created for each species by pooling RNA before and after amplification. The reference pool was made up of RNA from six different samples: two base-line control samples from the beginning of the experiment, two treatment samples from the end of the four-hour hypo-osmotic exposure, and two time-control samples from the end of the four-hour exposure time. To accurately compare the transcriptomes of Mytilus galloprovincialis and M. trossulus, we chose to develop a common microarray format that could be used for both species. This microarray design consisted of probe sequences generated from the out-group species, M. californianus. M. trossulus and M. galloprovincialis are approximately 7.5 million years divergent from M. californianus, yet only 3.5 million years divergent from each other (Seed, 1992). Therefore, heterologous hybridization to the microarray allowed us to compare transcriptional responses of M. galloprovincialis and M. trossulus without the inherent sequence biases that would result from a microarray that was designed from sequences of either M. galloprovincialis or M. trossulus. A limited number of sequences (556) from ESTs from M. galloprovincialis that matched M. californianus ESTs were included on the microarray to test for the effects of sequence mismatches. Only probes that performed well for both M. galloprovincialis and M. trossulus were used in our analyses. In order to determine significant changes in expression, we conducted a two-way ANOVA, in which salinity and species were modeled as fixed effects, and focused on genes that were significant for the salinity effect or the species x temperature interaction. We ignored the species term from the ANOVA as this effect could have highlighted genes that differentially bound to probes on the microarray due to differences in sequence homology, thus not reflecting true differences in gene expression. In accordance with statistical convention, all genes with a significant species x temperature interaction were deemed not to have significant temperature effects, even if the temperature term from the ANOVA had a low P-value. All genes with FDR-corrected (Benjamini and Hochberg, 1995) P-values less than 0.05 were considered significant. Analyses were conducted in the R statistical programming environment (R Development Core Team, 2009).
Project description:We used a cDNA microarray previously defined for the marine sentinel organism Mytilus galloprovincialis (MytArray1.0) to evaluate the effects of nanomolar doses of combined metal salts (50, 100 and 200 nM mixtures of Cd, Cu and Hg) after 48 hours of mussel exposure. Pointing to the mussel gills, first target of toxic water contaminants and actively proliferating tissue, we found significant dose-related increases of cells with micronuclei and other nuclear abnormalities in the treated mussels, with differences in the bioconcentration of the three metals determined in the mussel pulp by atomic absorption spectrometry. Following gill RNA purification and DNA microarray analysis, individual gene expression profiles revealed some transcriptional changes at the 50 nM dose, and substantial increases of differentially expressed genes at the 100 and 200 nM doses with roughly similar amounts of up- and down-regulated signals. The functional annotation of transcripts with consistent expression trends and significantly altered at least in one dose point disclosed the complexity of the induced cell response.
Project description:We used a cDNA microarray previously defined for the marine sentinel organism Mytilus galloprovincialis (MytArray1.0) to evaluate the effects of nanomolar doses of combined metal salts (50, 100 and 200 nM mixtures of Cd, Cu and Hg) after 48 hours of mussel exposure. Pointing to the mussel gills, first target of toxic water contaminants and actively proliferating tissue, we found significant dose-related increases of cells with micronuclei and other nuclear abnormalities in the treated mussels, with differences in the bioconcentration of the three metals determined in the mussel pulp by atomic absorption spectrometry. Following gill RNA purification and DNA microarray analysis, individual gene expression profiles revealed some transcriptional changes at the 50 nM dose, and substantial increases of differentially expressed genes at the 100 and 200 nM doses with roughly similar amounts of up- and down-regulated signals. The functional annotation of transcripts with consistent expression trends and significantly altered at least in one dose point disclosed the complexity of the induced cell response. Three-condition experiment (50, 100 and 200 nM doses), individual treated mussel vs. pooled control mussels (N=5), 3 biological replicates with dye-swap competitive hybridization (array A and B, 2 technical replicates/array).
Project description:This project aimed to disclose the metabolic alterations and responses of the marine mussel Mytilus galloprovincialis after grazing the toxic microalga Prorocentrum lima. Mussels metabolic alterations were investigated by shotgun proteomics, during the phases of intoxication and depuration. The diarrhetic shelllfisf toxins were also quantified in this project, for assessing the levels of contamination of mussels.
Project description:Transcriptional profiling of the digestive gland tissue of female mussel Mytilus galloprovincialis exposed to TCDD, n-TiO2 and their binary mixture Background: Exposure of marine organisms to pollutant mixtures may affect the pattern of contaminant uptake/bioaccumulation, as well as of gene expression in the tissues. Despite the growing concern over the potential biological impact of nanoparticles (NPs) in the aquatic environment, little is known about their interactions with other pollutants.We have recently shown that in the marine mussel Mytilus galloprovincialis exposure to n-TiO2, one of the most widespread type of NPs in use, in combination with 2,3,7,8-TCDD, chosen as model organic xenobiotic, can exert antagonistic or synergistic effects on different biomarkers from the molecular to the tissue level, depending on cell/tissue and type of measured response. An integrated approach involving immunhistochemical and transcriptomic analysis was employed to clarify the itteractive effects of n-TiO2 and TCDD in mussels digestive gland. In particular,TCDD bioaccumulation was evaluated utilizing specific anti-TCDD fluorescent antibodies. Moreover, immunohistochemical evaluation of antioxidant and cytoskeletal components was performed. To provide clues about how the molecular response to the investigated compounds is modulated, we used a cDNA microarray with1673 sequences. In animals exposed only to TiO2, functional genomics analysis of the microarray data (48 differentially expressed genes (DEGs)) highlighted three biological processes, largely dominated by the up-regulation of microtubule-based movement-related genes. Exposure to 2,3,7,8-TCDD yielded 49 DEGs exhibiting distinct patterns in terms of biological processes. Finally, exposure to the mixture rendered 62 GEGs characterized by the regulation of response to chemical stimulus, microtubule-based movement and intracellular signal transduction. Our data should be carefully considered in view of the biological effects of emerging pollutants, particularly in case of mixture chemicals.