FIG. 4.

Disruption of DRMs leads to a loss of infectivity of NH₄Cl-arrested virions in TVA800-expressing cells but not in cells expressing TVA950. To disrupt DRMs, human 293 cells expressing TVA800 (A) or TVA950 (C) were treated for 15 min with SFM containing 15 mM MβCD, 293 cells expressing TVA800 were treated with 40 μg of Fumonisin B1/ml for 60 h (B), or the cells were left untreated before challenge with RCASBP(A)-EGFP. Where indicated, a 6-h block to infection was imposed with 30 mM NH₄Cl added just prior to (t = 0) or 60 min after (t = 60) initiating infection. The number of resultant EGFP-positive cells was determined by flow cytometry ∼100 h after initiating infection. The efficiency of infection is shown as a percentage of that level obtained with untreated cells (MOI = 1.6 [A], 0.16 [B], and 1.4 [C] EGFP-transducing units). In each case, a representative experiment performed in triplicate is shown. Error bars represent the standard deviations of the data.