FIG 6.

Nonlytic viral egress is reduced by Ala substitutions of the carboxy-terminal Leu of the VP2 YPX₃L late domain motifs. (A) Extracellular virus quantified by RT-qPCR following electroporation of wild-type (HM175/p16) or the related L1-A, L2-A, L1,2-A, or replication-incompetent Δ3D^pol mutant RNAs. See legend to Fig. 2B for details. (B) Intracellular viral RNA abundance 9 days after transfection of the indicated wt or mutant virus. Abundance was normalized to that present in cells transfected with the replication-incompetent Δ3D^pol RNA. (C) Isopycnic iodixanol gradients were loaded with virus present in supernatant fluids of cultures 9 days following electroporation of the single L1-A or L2-A motif mutants, and fractions were assayed after centrifugation for HAV RNA by RT-qPCR. Virus present in the peak fractions (fraction 12, 1.086 g/cm³) was sequenced, and the presence of each mutation was confirmed. (D) Orientation of the side chains of Leu¹⁴⁹ (L149) and Leu¹⁸² (L182) (magenta) within the HAV capsid, showing the lack of a direct interaction between these residues.