FIG. 5.

MNV-1 infection is caveolin independent. (A) BMDMs were isolated from caveolin 1 knockout mice and wt controls and infected with MNV-1 at an MOI of 2. Viral titers were determined at times indicated. (B) RAW 264.7 cells were transfected with a DN GFP-tagged caveolin 1 (CAV 1 DN) and a GFP-only control (GFP) construct and infected with MNV-1 at an MOI of 10 for 12 h. VPg-expressing cells were determined by immunofluorescence and normalized to the value for the GFP-only control. (C) RAW 264.7 cells were incubated with an Accell siRNA caveolin 1 construct (CAV 1 siRNA) or a nontargeting construct (NT siRNA) (Dharmacon) for 72 h. Cells were then infected with MNV-1 or VSV at an MOI of 10, and VPg expression was determined by immunofluorescence 12 h after infection. The number of VPg-expressing cells was normalized to the value for the NT control. (D) To verify caveolin 1 protein knockdown, protein samples from cells expressing each siRNA construct were analyzed by immunoblotting for caveolin 1 and quantitated as described in the text.