Effects of cadmium exposure and heat shock on protein synthesis in gill tissue of the sea mussel mytilus edulis L.

Abstract

1. Sea mussels were exposed to different concentrations of Cd 2+ for short periods of time. The gills were then isolated and incubated with radiolabelled methionine or cysteine. The exposure to cadmium resulted in a dose-dependent inhibition of amino acid incorporation into gill soluble proteins. The inhibition was independent of the exposure time. 2. Cd 2+ induced the expression of two types of specific proteins: metallothionein-like proteins and heat shock proteins of the high molecular weight. 3. In vivo heat shock caused a slight decrease of methionine incorporation by the gills but induced a set of heat shock proteins with molecular weight of 30, 32, 68, 70, 80, 82, 90 and 110 kDa. 4. Exposure of the mussels to cadmium followed by heat shock resulted in a strong inhibition of the incorporation of methionine. The pre-exposure to cadmium differentially enhanced the expression of the heat shock proteins.