Fig. 4. Expression profiles of signal transduction genes expressed during osmotic stress in G. mirabilis gill tissue. (A) Serum and glucocorticoid regulated kinase isoform 1 mRNA (SGK-1; Gm_11g08). (B) Protein kinase C mRNA (PKC-). (C) Lipid phosphate phosphatase 2 mRNA (LPP-2). (D) Ras-guanyl releasing protein 1 mRNA (Ras-GRP-1). Data points were plotted and labeled as described previously. (E) Phosphorylated protein kinase C (PKC) substrate protein expression as determined by western blot analysis. Relative intensity was calculated by normalizing intensities against a standard protein loaded on each gel. The resulting value was then averaged from each of the three fish at each treatment (hyperosmotic stress shown as filled bars; hypo-osmotic stress shown as open bars; control and time=0 shown as gray bars) and time point (1, 2, 4, 12 h post-exposure) to yield the mean relative intensity values illustrated. Filled stars denote significant expression during hyperosmotic stress. Open stars denote significant expression during hypo-osmotic stress. Values are shown ± s.e.m. P<0.05.