Establishing the barnacle Balanus improvisus as a potent invertebrate monitoring system in marine ecotoxicogenomics

Conference poster, 2009

There is a need for potent invertebrate systems for assessing the impacts of environmental contaminants on marine ecosystems. Balanus improvisus, a marine athropod, has a number of promising characteristics that make it a good candidate in such efforts. We have conducted sequencing of a cDNA library from the cyprid larval stage and identified several detoxification systems as well as novel B. improvisus specific genes. To investigate the toxicological gene expression response in this organism, we performed a short-term exposure experiment of the cyprid larvae to two different biofouling substances. From a natural population of B. improvisus, 300 - 1000 cyprids were treated for 23 hours with 390nM CuO or with two different concentrations (10nM or 10μM) of meditomidine. Protein expression changes were studied by 2D-PAGE analysis after DIGE labelling. For gene expression analysis by DNA miroarrays total RNA was extracted and used for cDNA and cRNA/aRNA templates. Roughly 2000 B. improvisus genes were studied represented by 3000 different probes on the arrays (each in duplicates). Candidate genes were confirmed by qPCR. A number of protein expression changes were detected on the 2D gels as a result of the different treatments. Interestingly, the response to the different treatments clearly formed distinct groups in principle component analysis. The DNA microarray analysis revealed several genes as toxicity indicators, e.g. various heat shock proteins, some proteases and factors involved in regulatory processes (transcription factors). Our data indicate that B. improvisus may serve as a tool to evaluate the impacts of marine pollution, and thus to fill the niche as an important invertebrate marine model organism for ecotoxicology and environmental genomics.