Characterization of an aryl hydrocarbon receptor from a cetacean : an approach for assessing contaminant susceptibility in protected species
Jensen, Brenda A.
MetadataShow full item record
Some cetaceans bioaccumulate substantial concentrations of halogenated aromatic hydrocarbons (HAH) in their tissues, but little is known about the effects of such burdens on cetacean health. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related HAH cause toxicity via activation of the aryl hydrocarbon receptor (AHR), a member of the bHLH-PAS family of transcription factors. Differences in AHR structure and function are known to contribute to species-specific differences in susceptibility to HAH toxicity, and targets for HAH toxicity are related to the tissue-specific expression of AHR. The goal of these studies was to ascertain the potential for HAH effects in cetaceans by characterizing the AHR from the beluga, Delphinapterus leucas. The beluga AHR was characterized by its molecular structure, capacity for ligand binding, structure-binding relationships with various classes of HAH, as well as tissue-specific expression. These results show that: 1) in an in vitro system, the beluga AHR possesses binding affinities similar to AHRs of other mammals that are considered sensitive to toxic effects of HAH, 2) Structure-activity relationships are consistent with a common mechanism of coplanar HAH action among cetaceans and rodent species, and 3) the AHR protein is expressed in many tissues of the beluga, and is present at high levels in lymphoid organs, liver and lung. Together, these data suggest that cetaceans can be considered sensitive to the action of coplanar HAH. Further, using in vitro expressed proteins is a promising approach for addressing molecular and biochemical questions about PHAH toxicity in endangered and protected species where logistical and ethical concerns preclude testing in live animals.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2000
Suggested CitationThesis: Jensen, Brenda A., "Characterization of an aryl hydrocarbon receptor from a cetacean : an approach for assessing contaminant susceptibility in protected species", 2000-09, DOI:10.1575/1912/4071, https://hdl.handle.net/1912/4071
Showing items related by title, author, creator and subject.
Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers Manning, Cara C. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2017-02)In this thesis, I use coastal measurements of dissolved O2 and inert gases to provide insight into the chemical, biological, and physical processes that impact the oceanic cycles of carbon and dissolved gases. Dissolved ...
Coral reefs in the Anthropocene Ocean: novel insights from skeletal proxies of climate change, impacts, and resilience Mollica, Nathaniel R. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2021-02)Anthropogenic emissions of greenhouse gases are driving rapid changes in ocean conditions. Shallow-water coral reefs are experiencing the brunt of these changes, including intensifying marine heatwaves (MHWs) and rapid ...
Scientific results of the "Nautilus" Expedition, 1931 : under the command of Capt. Sir Hubert Wilkins. Parts I to III Sverdrup, Harald U.; Soule, Floyd M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1933-03)In 1930 Sir Hubert Wilkins announced his plan for exploring the Polar Sea by submarine. Thanks to the courtesy of the U. S. Navy Department and the U. S. Shipping Board the submarine 0 12 was placed at his disposal and ...