Meeting Abstract

75.6  Monday, Jan. 6 09:15  Phylogenetic diversity and transcription dynamics of heat shock proteins in the estuarine cnidarian Nematostella vectensis REITZEL, A.M.*; TARRANT, A.M.; University of North Carolina, Charlotte; Woods Hole Oceanographic Inst. areitze2@uncc.edu

Individuals living in estuarine habitats routinely experience dynamic abiotic conditions requiring the inducible expression of gene batteries for maintaining homeostasis. Heat shock proteins (HSPs) are molecular chaperones that serve a central function in mediating the response to environmental stress but also participate in other processes, particularly development. HSPs, especially in the larger size classes, are broadly conserved in eukaryotes and, at the same time, diverse, with multiple genes per class with particular cellular localization and inducibility. Thus, studying the expression dynamics for individual HSPs is informed by an assessment of orthology when comparing among species. We report the phylogenetic diversity of HSPs from the starlet sea anemone Nematostella vectensis, a resident of estuaries throughout North America, and quantified gene expression of identified HSP70s (n = 5), HSP90s (n = 3), and a HSP110 (n = 1) during development and when exposed to temperature shock and cadmium. All HSPs surveyed had significant differences in expression over a developmental time course from embryogenesis to adult, typically with peak expression during larval stages. However, in response to temperature shock and metal exposure, about half of the HSPs showed increased expression, with treatment-specific variation in HSP induction. The differences in transcription dynamics correlate with predicted transcription factor binding sites for Heat Shock Factor 1, a common regulator of HSPs. We compare these data with our previously published results on the thermal oscillations in Nematostella’s habitat and stage-specific variation in thermotolerance.