Fig. 4.

Relative expression of PtHSP60 mRNA in various tissues of P. trituberculatus during normal salinity (25 ppt) and salinity challenges (10 or 40 ppt), as determined by semi-quantitative RT-PCR. The examined tissues of three crabs in each group were collected. The β-actin RNA was used as an internal and the relative expression levels of PtHSP60 were obtained relative to β-actin expression. Values are expressed as means ± SD of the relative variations (fold induction) between each treatment (10 or 40 ppt) and the control sample (25 ppt); asterisks beside the bars indicate statistically significant differences (*P < 0.05)