HOFMANN, G.E.; University of California, Santa Barbara: Some Like It Hot, Some Like It Cold: Hsp Gene Expression in Ectothermic Marine Organisms

The goal of my research program is to employ biochemical and molecular techniques to gain ecological insight into the role of temperature in setting species� distribution patterns in the marine environment. The central focus is the study of the environmental regulation of gene expression, where we are particularly interested in a set of inducible molecular chaperones, the heat-shock proteins (Hsps), and how the expression of these genes varies with the thermal history of organisms in natural populations. Our primary study organisms are intertidal invertebrates and marine fish that experience dramatic changes in body temperature on varying temporal and spatial scales. In this presentation, I will present studies that address the variable expression of Hsps, how these genes are differentially regulated in ectothermic animals in response to ecologically relevant temperature conditions, and how such plasticity in gene expression contributes to physiological plasticity in the environment. In addition, an emerging ecological genomics approach in our research has created the opportunity to mine for the genes that are varying in an environmental context, and I will discuss these new directions in the talk. Finally, in keeping with the Bartholomew tradition in ecological physiology, the presented studies will highlight the integration of field and laboratory approaches. Supported by NSF grants IBN 9723063, OPP 0087971 and Worster Scholar funds.