HEAD, J.M.; TERWILLIGER, N.B.; Univ. of Oregon, Oregon Institute of Marine Biology; Univ. of Oregon, Oregon Institute of Marine Biology: The role of HIF-1a in crustacean responses to hypoxia.

The habitats of most aquatic crustaceans are highly variable, particularly with respect to changing levels of oxygen. Fluctuations in factors such as salinity, temperature, and productivity levels can have significant effects on the amount of oxygen available in the medium. Some estuarine species of crustaceans are not only subject to short term hypoxia as would be experienced due to a tidal cycle, but also to long term seasonal hypoxia. We are interested in investigating the possible role of HIF-1a in the ability of hypoxia tolerant crustaceans to adapt to fluctuations in oxygen availability via oxygen-dependent changes in gene expression. Some crustaceans have been shown to differentially regulate the subunits of their oxygen transport proteins in response to low oxygen in order to change the oxygen affinity of the molecule, but the regulatory mechanism in crustaceans has not yet been demonstrated. We have identified a HIF-1a homologue in the brachyuran crustacean Cancer magister that is highly similar to the HIF-1a homologue, SIMA, from Drosophila melanogaster. It appears that the HIF-1 system is present in crustaceans and probably plays a significant role in regulating gene expression in an oxygen dependent manner. Supported by an NSF IGERT Fellowship, Eugene and Clarissa Evonuk Graduate Fellowship, and NSF 9984202.