Meeting Abstract
P1.51 Saturday, Jan. 4 15:30 The Conservation and Function of the Cytoprotective Transcription Factor Nrf2 in a Model Cnidarian KANE , E.G.*; REITZEL, A.M.; University of North Carolina, Charlotte; University of North Carolina, Charlotte ekane1@uncc.edu
The cell is constantly exposed to damaging reactive oxygen species resulting from aerobic metabolism and anthropogenic pollution. In response, the cell must orchestrate dynamically regulated antioxidant defenses that maintain cellular and tissue integrity. A master regulator of the antioxidant response is the bZIP transcription factor nuclear factor erythroid-derived 2 (Nrf2). In mammals, Nrf2 coordinates response to stress and tissue wounding, thereby deterring aging, and also serves critical roles in cell specification during development. Nrf2 and its function are conserved in model protostome lineages, where orthologs in C. elegans and Drosophila are crucially important for antioxidant defense and play a significant role in development of mesendodermal tissue. The presence and function of Nrf2 in earlier diverging phyla remains unclear but critical for determining the antiquity of this mechanism for cellular homeostasis. Using the sea anemone Nematostella vectensis, we identified a single Nrf2 ortholog (nvNrf) with high sequence similarity in the DNA-binding region, but not critical residues for interactions with regulatory proteins. Morpholino-mediated suppression of nvNrf during development provided evidence that this transcription factor plays a role in the transition from planula to juvenile by repressing tentacle development. Exposure of Nematostella to two model pro-oxidants, tBOOH and tBHQ, showed this cnidarian is sensitive to oxidative stress. Measurement of expression for nvNrf and a conserved suite of antioxidant response genes suggests that this cnidarian utilized similar stress response pathways as model bilaterians. Together, these data support a multi-faceted role for Nrf in both development and stress response in Nematostella.
