Meeting Abstract
Organisms in estuarine habitats experience dramatic changes in temperature and other abiotic factors over daily and seasonal time scales. For species with broad geographic ranges, the magnitude and duration of thermal stress will vary, which may result in divergent responses between individuals as a result of local adaptation. The starlet sea anemone, Nematostella vectensis, inhabits estuaries along the United States’ Atlantic coast where individuals experience >20°C changes every day and more than 40°C over a year. The range of temperatures as well as the mean high temperatures vary along this coast due a sharp thermocline from Florida to Maine to which many species show evidence for thermal adaptation. For this research, anemones were collected from throughout their native range and used to examine the effects of temperature changes on cellular stress. A group of inducible heat shock proteins (HSP) are produced in response to stress, such as temperature increases, and can be used as biomarkers. Individuals from three genetically distinct anemone populations in Maine, Massachusetts, and North Carolina were studied to compare the interpopulation differences in inducible HSP production in response to temperature change. Quantitative PCR was used to measure HSP expression in response to acute [two degrees Celsius every hour for eight hours (20 – 36°C)] and chronic temperature treatments. Our results reveal significant differences in expression of these HSPs with respect to the magnitude and duration of temperature increase but little variation between populations. Studying the interpopulation differences in response to temperature change can provide insight on how sea anemone populations will respond to climate change throughout its native range.
