HOFMANN, G.E.: Molecular chaperones in intertidal organisms: Biochemical function and gene expression

The intertidal zone has historically been an important natural laboratory in which to test ideas about how physical factors such as temperature are transduced through organismal physiology to influence the distribution patterns of organisms. Key to our understanding of how the physical environment influences organismal distribution is to identify physiological processes that have ecological relevance. In my lab, we have focused on biochemical- and molecular-level physiology that would contribute to thermal tolerance and maintenance of a functional intracellular protein pool in the face of extreme and fluctuating environmental temperatures. Past research has addressed processes central to protein homeostasis (e.g., protein ubiquitination) and the molecular ecology of molecular chaperones, a.k.a. heat shock proteins (Hsps), in ectothermic animals. In this presentation, I will focus on two new developments regarding the biology of molecular chaperones in intertidal organisms. Specifically, I will present data on the biochemical function of molecular chaperones purified from our non-model study organisms and discuss the temperature relationships of these molecules as they function to assist in protein folding in situ. In addition, I will present data on the functional characteristics of the transcriptional factor, HSF1 and discuss how these data relate to the plasticity of Hsp gene expression that is observed in intertidal organisms in nature.