ARE THERE SALINITY STRESS PROTEINS

To establish whether osmotic stress can be separated from possible tox icant stress in Eurytemora affinis, protein synthesis was analyzed und er various conditions of temperature and osmotic stress. Individual ad ult copepods raised at 10 ppt and 15 degrees C were exposed for 5 h to different temperature and salinity regimes. Newly synthesized protein s were separated and identified using SDS-PAGE and autoradiography. Co pepods exposed to lower (2 and 5 ppt) and higher (15 and 20 ppt) salin ities showed differences in the up- and down-regulation of specific pr oteins. Concurrent heat stress changed these protein patterns. These r esults suggest that protein profiles might be used to distinguish the effect of toxicants in a salinity gradient such as the Chesapeake Bay or in the Baltic region.