Specific protein responses in the calanoid copepod Eurytemora affinis (Poppe, 1880) to salinity and temperature variation

The distribution of the calanoid copepod Eurytemora affinis (Poppe, 1880) in the Chesapeake Bay seems to be limited by salinity and temperature. Results in the laboratory suggest it should be able to accommodate to the entire range of salinity-temperature combinations encountered. Yet, at high temperatures and salinities, in particular, E. affinis is not found. In this study, we examined changes in protein expression in E. affinis exposed to extreme temperature-salinity combinations as well as to salinity-temperature combinations where they are found in the Chesapeake Bay. The protein changes observed were specific to treatment. The number of proteins present or absent compared to intermediate conditions tended to increase with the degree of stress. Some of these proteins may be involved in regulation of free nonessential amino acids or have direct interaction with inorganic ions. (C) 2001 Elsevier Science B.V. All rights reserved.