Figure 5.

The effect of MyD88 and Relish gene knockdown on ALFPm3 and ALFPm6 transcripts levels upon V. harveyi infection. (a) Efficiency of MyD88 and Relish gene silencing mediated by dsRNA in shrimp. Control groups were injected with 0.85% NaCl or GFP dsRNA. The experimental groups were shrimp injected with 10 μg/g shrimp MyD88 dsRNA and Relish dsRNA. At 0, 24, 48 and 72 h post-dsRNA injection, haemolymph was collected from 36 individual shrimp and randomly divided into 3 pools (n = 3 in each pool). The transcription levels of MyD88 or Relish were analysed using qRT-PCR. Elongation factor-1α (EF1α) was used as an internal control. (b) MyD88 and Relish gene silencing in V. harveyi-infected shrimps. The transcriptional level of MyD88 and Relish genes in the haemolymph of MyD88 dsRNA and Relish dsRNA-challenged shrimp, respectively, at 0, 6 and 24 h post-V. harveyi infection was determined. The control was shrimp injected with GFP dsRNA. EF1α was used as the internal control gene. (c) Silencing of the MyD88 and Relish genes affected the expression of the ALFPm3 and ALFPm6 genes. The expression of the ALFPm3 and ALFPm6 genes in the MyD88 and Relish gene-silenced shrimp upon V. harveyi challenge was determined by qRT-PCR. The control was shrimp injected with GFP dsRNA. The ALFPm3 and ALFPm6 gene expression levels were normalized to EF1α. The expression of the ALFPm3 and ALFPm6 genes in the V. harveyi-infected group at 6 and 24 hpi was normalized to that of the control group at 0 hpi. The graph shows the means ± standard deviations of 3 independent sets, **P < 0.01.