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:Direct comparison of the transcriptional patterns between male and female in the digestive gland of a natural population of the marine mussel Mytilus galloprovincialis sampled in the Bizerta Lagoon, Tunisia, across November 2007 -February March 2008 (four stages, winter peak). Background: Seasonal environmental changes may affect the physiology of Mytilus galloprovincialis (Lam.), an intertidal filter-feeder bivalve occurring commonly in Mediterranean and Atlantic coastal areas. We investigated seasonal variations in relative transcript abundance of the digestive gland and the Digestive gland (gonads) of males and females. To identify gene expression trends, we used a medium-density cDNA microarray (1.7 K probes) in dual-color competitive hybridization analyses. Results: Hierarchical clustering of digestive gland microarray data showed two main branches, distinguishing profiles associated with the “hot” months (May–August) from the other months. Genes involved in chitin metabolism, associated with mussel nutrition and digestion, showed higher expression during summer. Moreover, we found different gene expression patterns in the digestive glands of males and females during the four stages of mussel gonadal development. Microarray data from gonadal transcripts also displayed clear patterns during the different developmental phases with peak relative mRNA abundance at the ripe phase (stage III) for both sexes. Conclusion: These data showed a clear temporal pattern in gene expression profiles of mussels sampled over an annual cycle. Physiological response to thermal variation, food availability, and reproductive status across months may contribute to variation in gene expression. Test/reference design (female/male). Direct comparison of RNA extracts obtained from the Digestive gland tissue of female and male animals. Two (male, female) x four conditions (gonad developmental stage 1, stage 2, stage 3, stage 4). Dual color competitive hybridizations with label swap. Single individuals. Four biological replicates. One replicate per array.

Dataset Information

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets