FIG. 2.

Effect of proteasome inhibitor on the expression of NSs. Vero cells infected with ZH548 (lanes 2 to 4) or clone 13 (lanes 5 to 7) or mock infected (lane 1) were untreated (lanes 2 and 5) or treated with 20 μM MG132 (lanes 3 and 6) or 10 μM lactacystin (lanes 4 and 7) and labeled from 8 to 10 h p.i. with 200 μCi of a mixture of [³⁵S]methionine and [³⁵S]cysteine per ml. Proteins from total cellular extracts were immunoprecipitated with anti-NSs antibodies and analyzed in a sodium dodecyl sulfate–17.5% polyacrylamide gel. The positions of the viral proteins NSs and N (on the left) and the molecular mass markers (on the right) are indicated. In this experiment, the N protein migrated as a doublet, a situation observed occasionally.