E-GEOD-48062 - Heat and nickel induced mRNA changes in mussels
Released on 19 June 2013, last updated on 3 May 2014
Transcriptional profiling of the digestive gland tissue of female mussel Mytilus galloprovincialis exposed to nickel along with a temperature gradient Background: The exposure of marine organisms to stressing agents may affect the level and pattern of gene expression. Although many studies have examined the ecological effects of heat stress on mussels, little is known about the physiological mechanisms that might be affected by co-exposure to heat stress and environmental contaminants such as nickel (Ni). In the present work we investigated the effects of simultaneous changes in temperature and Ni supply on lysosomal membrane stability (LMS) and malondialdehyde accumulation (MDA) in the digestive gland (DG) of the blue mussel Mytilus galloprovincialis (Lam.). To shed some light into how the molecular response to environmental stressors is modulated, we employed a cDNA microarray with 1,673 sequences to measure the relative transcript abundances in the DG of mussels exposed to Ni along with the temperature increase. Temperature and Ni rendered additive effects on LMS and MDA accumulation, increasing the toxic effects of metal cations. Ni loads in DG tissues was also affected by co-exposure to 26°C. In animals exposed only to heat stress, functional genomics analysis of the microarray data (171 DEGs) revealed 7 biological processes, largely dominated by the up-regulation of folding protein-related genes, and the down regulation of genes involved in cell migration and cellular component assembly. Exposure to Ni at 18°C and 26°C rendered respectively 188 and 262 DEGs showing distinct pattern in term of biological processes. In particular, the response of mussels exposed to Ni at 26°C was characterized by the up regulation of proteolysis, ribosome biogenesis, response to unfolded proteins and catabolic-related genes as well as the down-regulation of genes encoding cellular metabolic processes. Our data provide new insights on the transcriptomic response in mussels challenging temperature increases and Ni exposure and should be carefully considered in view of the biological effects of heat stress and particularly in polluted areas. Digestive gland tissue from individual animals in different experimental conditions were analyzed in a complete loop design. Dual color competitive hybridizations (Control “16°C” vs “20°C” vs “24°C” vs “16°C+Cu”, “20°C” vs “24°C” vs “20°C+Cu”, “24°C” vs “24°C+Cu”, “16°C+Cu” vs”20°C+Cu” vs “24°C+Cu”; “20°C+Cu” vs “24°C+Cu”) including label swap. Single individuals. Four biological replicates. One replicate per array.
transcription profiling by array
Mohamed Banni <email@example.com>, Aldo VIARENGO, Alessandro NEGRI, Mohamed BANNI