(A) Schematics of the wild type, Erns deletion (CSFVΔErns), and polymerase dead (GAA) CSFV RNA, and the experimental procedure. (B) Expression of the full length of HA-tagged Erns (HA-Erns), HA-ApoA1, HA-ApoC1, and HA-ApoE was determined by immunoblotting at 48-h post-transduction of lentiviruses into SK6 cells. Intracellular CSFV RNA (C) and extracellular infectious titers (D) were determined at 72-h post-electroporation with CSFVΔErns by qRT-PCR and focus-forming assay, respectively. (E) Expression of HA-Erns, Hel, and HA-ApoE was determined by immunoblotting at 48-h post-transduction of lentiviruses into SK6 cells. Intracellular CSFV RNA (F) and extracellular infectious titers (G) were determined at 72-h post-electroporation with CSFVΔErns by qRT-PCR and focus-forming assay, respectively. In all cases, asterisks indicate significant differences (* p < 0.01) versus the results of the control cells.