Figure 4. Assembly properties of SFV 190-TCat 37 °C vs. 28°C.

BHK-21 cells were electroporated with WT SFV or 190-TC mutant viral RNA, incubated for 15 h at 28°C, pulse-labeled with [³⁵S]-methionine/cysteine for 1 h at 28°C, and chased for 0 h or 3 h at 37 °C or 10 h at 28 °C. At the end of each chase period the media were collected and the cells were lysed. Left panel: Aliquots of the cell lysates were analyzed directly by SDS-PAGE. The positions of the envelope proteins p62, E2 and E1 and of the 190-TC-capsid (TC-C) and WT capsid (C) proteins are indicated. Note that TC-C migrates slower than C, and that there is a non-specific protein that migrates slightly above the E1 protein. Right panel: Samples of the chase media were immunoprecipitated with a polyclonal antibody against the E1 and E2 glycoproteins in the absence of detergent to recover intact virus particles (Liao and Kielian, 2006). The proteolytically truncated form of E1 E1s (Lu et al., 2001) is labeled with an asterisk. Shown is a representative example of two independent experiments.