Meeting Abstract

118.6  Saturday, Jan. 7  Activation of cellular defenses in the sea anemone Nematostella vectensis by PAHs and crude oil TARRANT, A.M.*; REITZEL, A.M.; KWOCK, C.K.; GOLDSTONE, J.V.; JENNY, M.J.; WHOI; WHOI; Chinese University of Hong Kong; WHOI; Univ. of Alabama atarrant@whoi.edu

Throughout evolution, animals have needed to detect and respond to chemical and physical stressors. Cellular defenses such as xenobiotic metabolism, antioxidant metabolism, and chaperone activity are mediated through deeply conserved gene families including cytochrome P450s, superoxide dismutases (SODs), and heat shock proteins (HSPs). While these functions are broadly conserved, diversification within gene families has resulted in lineage-specific adaptations as well as variable sensitivity to stressors. The specific roles for individual genes in mediating stress responses are unknown in most invertebrates, particularly aquatic species. Using qPCR and a targeted microarray, we are characterizing the effects of exposure to polycyclic aromatic hydrocarbons (PAHs) and crude oil on the expression of defensive genes in the sea anemone Nematostella vectensis. Nematostella has a sequenced genome, is amenable to laboratory manipulation, and inhabits a dynamic estuarine environment in which it may be routinely exposed to coastal pollutants. Exposure of Nematostella to benzo[a]pyrene (10-500 ppb) for 96 hours induced expression of a manganese SOD and catalase. Co-exposure to benzo[a]pyrene and ultraviolet light resulted in altered gene expression consistent with phototoxicity. Exposure of Nematostella to water equilibrated with crude oil (Macondo sweet crude oil, up to 20 ppm), in the presence or absence of dispersant (2 ppm Corexit) resulted in modest and variable induction of cytosolic HSP70, and little to no induction of SODs or catalase. Microarray experiments are in progress to determine whether expression of other defensive genes is affected by oil exposure. Collectively, these studies conducted within Nematostella provide insight into both the evolution of animal stress responses and their diversification within Cnidaria.