Figure 5.

Recovery of the viral RNA in Chum salmon heart-1 cells (CHH-1) supernatant after infection with SAV3 with a mutation in the N-glycosylation sites in E1 and E2. The dots represent Ct values from RT-qPCR run with reverse transcriptase and thus both viral RNA and carryover plasmid DNA. The Ct values of rSAV3, rSAV3 E2_319A and rSAV3 E2_319Q (black dots) constructs decrease for each passage, indicating an increasing viral RNA concentration in the cell culture medium. Ct value for rSAV3 constructs containing mutations in E1 (grey dots), i.e., prSAV3 E1_35Q, prSAV3 E1_35A, prSAV3 E1_35Q/E2_319Q, and prSAV3 E1_35A/E2_319A increase with each passage and no Ct is observed by P4.