Meeting Abstract
21.1 Friday, Jan. 4 Profiling gene expression responses of the symbiotic anemone, Aiptasia pallida, to elevated temperature and light conditions using RNA Seq HANES, S D*; KEMPF, S C; MEYER, E; Auburn University; Auburn University; Oregon State University shanna.hanes@gmail.com
Coral reefs have dramatically declined over the past few decades as a result of mass mortality bleaching events. Bleaching functions as a stress response to elevated temperature and/or light conditions resulting in the loss of intracellular dinoflagellates (Symbiodinium) from host gastrodermal tissues. This process involves a complex series of events that occur throughout the duration of the bleaching episode and involve cellular interactions between both symbiotic members. However, few studies have investigated the early host stress response when symbiotic breakdown is initiated. In this study, molecular techniques were employed to characterize the host response during the first 48 hours of heat and light stress in Aiptasia pallida. Both symbiotic and aposymbiotic anemones were exposed to stress conditions of ~32.5oC at 140 umols irradiance for 12 hours daily followed by 12 hours of darkness at ambient temperature. Differential gene expression was measured at various time points (0, 3, 12, 24, and 48 hours) using an RNASeq procedure. Additionally, ultrastructural examinations of tentacle tissues at 0 and 48 hours were conducted using transmission electron microscopy in order to monitor cellular activities. Results from this investigation indicate that the gene expression profile of A. pallida changes during early stages of bleaching, and several key genes are identified that are involved in the host stress response. This study provides a better understanding of the genetic determinants of stress tolerance in a host anthozoan, and offers further insight into the cellular processes that underlie coral bleaching.
