Metabolism of and adaptation to arsenic in the earthworm, Lumbricus rubellus

As contamination in the terrestrial environment can have deleterious effects upon the flora and fauna exposed. The persistent nature of the metalliod provides a strong selective pressure that may lead to the occurrence of adapted populations. While certain organisms demonstrate tolerance, others are able to acquire genetically based resistance, whereby survival is ensured following exposure to concentrations that are normally lethal. Such resistance may come at a price, with reduction in genetic variability following speciation events potentially increasing the sensitivity of adapted species to future environmental stress, while diverting resources limiting overall fitness. It is therefore important to determine the sensitivity of populations and potential ecological implications of resistance. Our investigations compare exposure sensitivity to metals among naive and tolerant populations of the earthworm Lumbricus rubellus and evaluate the capacity for gene flow within contaminated environments via integration with phylogenetic data. Furthermore, we are employing a systems biology analysis (metabolomics and transcriptomics) to clearly resolve As metabolism within naive L. rubellus that will supplement investigations for the demonstration of genetic mechanisms adopted by adapted individuals using Restriction Associated DNA sequencing (RADseq).