Molecular cloning and differential expression of the glucocorticoid receptorgene in the estuarine tapertail anchovy Coilia nasus.

To understand the regulation of the glucocorticoid receptor gene (Gcr) during loading and transport stress in fish, the Gcr gene of Coilia nasus was cloned. Gcr in C. nasus is expressed strongly in the liver and muscle, and less stronglyin the gills, brain, spleen, intestine, trunk kidney, and head kidney. Gcr expression in both the liver and muscle was increased by loading and transport stress. NaCl reduced the death rate caused by loading and transport stress, and the expression of Gcr in liver and muscle differed significantly between the NaCl and non-NaCl groups. To investigate whether the elevated Gcr transcripts were translated into protein, proteins extracted from the liver and muscle were analyzed. In both tissues, C. nasus GCR protein expression patterns paralleled those of Gcr mRNA during stress.