A NOVEL 90-KDA STRESS PROTEIN-INDUCED IN FISH CELLS BY FISH RHABDOVIRUS INFECTION

A 90 kDa cellular protein in a fish cell, CHSE-214, showed increased e xpression by the infection of infectious hematopoietic necrosis virus (IHNV), heat shock, 2-mercaptoethanol, copper sulfate, and cadmium sul fate, and was detected in various kinds of cells such as human, rat, a nd mouse cells. The molecular mass of the 90 kDa protein was different from those of the hsp90 and grp94. In addition, all the anti-stress p rotein MAbs did not react with the 90 kDa protein. Finally, the subcel lular distribution of the 90 kDa protein, determined by Western blots of subcellular fractions, was found to be mainly nuclear, both in norm al and IHNV-infected CHSE-214 cells. The present results indicate that the 90 kDa protein is a kind of stress protein. However, based on its molecular mass, antigenic characteristics, and subcellular distributi on, it is likely that this protein is a novel stress protein that has not been previously described in animal systems, especially in fish sy stems. (C) 1997 Academic Press.