Transcriptomic profiling of Chamelea gallina from sites along the Abruzzo coast (Italy), subject to periodic localized mortality events

The striped venus Chamelea gallina (Linnaeus 1758) is a species of substantial economic importance, distributed along the Mediterranean coast and the Eastern Atlantic coasts. Due to an intensive trade activity since the 1970’s, this species has experienced a rapid decline in the last 30 years, still exacerbated by irregular mortality events due to undetermined triggers. Global profiling of gene expression has the potential to disentangle the biological effects of various environmental stressors causing severe landings decline or mortality events. In this study, we report the development of a C. gallina-specific oligo-microarray, a first transcriptomic platform for global gene expression profiling in the striped venus. This tool was applied to compare gene expression profiles of clams collected in different periods along the Abruzzo coast in a reference site (T7) and in a site subject to mortality events (T4). Our results reveal substantial transcriptional modifications among the investigated sites and the significant up-regulation of several genes involved in the immune response in the T4 site. The transcriptomic differences between clams from the two investigated sites endorse distinct health and metabolic status under different environmental stressors. Overall, this approach provides a preliminary indication about the potential causes of periodic localized mortality affecting C. gallina.