Complement-related pathway gene expression in controls and grouper challenged with 1.3 × 106 CFU/ml (20 μl/fish) Vibrio alginolyticus , as determined by qRT-PCR. ( A ) C7, ( B ) C8, ( C ) C8-d, ( D ) C9, ( E ) DAF, ( F ) MASP1/2, ( G ) HF, ( H ) IF ( I ) PLG, and ( J ) SERPING1. Values are presented as the mean ± SEM (n = 5). Values with different letters differ significantly. Significance was set at P < 0.05, as determined by one-way ANOVA followed by Duncan’s test.