Multi-stressor impacts on coastal Antarctic and temperate sea urchins

Coastal seas of the world are experiencing an unprecedented period of rapid change that is driven largely by human-induced alterations in climate and release of chemical contaminants into the environment. Polar areas appear particularly vulnerable as temperatures rise and toxicants accumulate suggesting that their synergistic effects could result in loss of fitness, recruitment, and survival in many species. However, life in general is very adaptable, with heritability and epigenetics as enduring mechanisms that shield future generations from effects of parental exposure to environmental stressors. To better understand adaptation and resilience in coastal keystone species, we propose to compare Antarctic and temperate sea urchins as models of molecular, genetic, epigenetic, and transgenerational effects. Understanding impacts from multiple stressors is critical to fully understand the environment which organisms are living in, and the impacts of changing those conditions. The overall aim of this project is to understand adult preconditioning impacts on spawning success and gamete/embryo sensitivity to multi-stressor impacts on DNA damage susceptibility and repair in sea urchin populations from latitudinal extremes. The project will take an eco-genotoxicological approach to address three specific objectives: Objective 1 Precondition aquarium stocks of Antarctic (Sterechinus neumayeri, British Antarctic Survey), and co-familial temperate (e.g., Psammechinus miliaris) sea urchins to end-century elevated water temperatures (+2degrees). Objective 2 Spawn both Antarctic and temperature species after 1 and 2 years acclimation followed by acute multi-stress exposures (e.g., reduced salinity and chemical genotoxic pollutant) to investigate multi-stress response after preconditioning. Objective 3 Assess adult, gamete, embryo, and larvae viability, development, and survival after acute multi-stress exposure; develop and assess DNA damage, DNA repair, and epigenetic regulation.