Sex-, gametogenesis, and tidal height-related differences in levels of HSP70 and metallothioneins in the Pacific oyster Crassostrea gigas.

Pacific oysters, Crassostrea gigas, living at a range of tidal heights, routinely encounter large fluctuations in temperature. We demonstrate that levels of heat shock proteins (HSP) and other stress proteins (metallothioneins, MTs) quantified by ELISA, remained similar in gills, mantle and digestive gland between oysters inhabiting low and high tidal heights. In contrast, endogenous HSPs and MTs levels in gonad changed significantly during gametogenesis.

Identification of differentially expressed genes of the Pacific oyster Crassostrea gigas exposed to prolonged thermal stress.

Groups of oysters (Crassostrea gigas) were exposed to 25 degrees C for 24 days (controls to 13 degrees C) to explore the biochemical and molecular pathways affected by prolonged thermal stress. This temperature is 4 degrees C above the summer seawater temperature encountered in western Brittany, France where the animals were collected. Suppression subtractive hybridization was used to identify specific up- and downregulated genes in gill and mantle tissues after 7-10 and 24 days of exposure.

Molecular characterization and expression of the gene encoding aspartate aminotransferase from the Pacific oyster Crassostrea gigas exposed to environmental stressors.

A partial cDNA encoding cytosolic aspartate aminotransferase (AST) (EC 2.6.1.