FIG. 1.

Membrane association of M1 protein in WSN virus-infected cells. (A) Pulse-chase analysis of WSN virus-infected MDBK cells. At 7 hpi, WSN virus-infected MDBK cells (5 × 10⁶) were pulse-labeled with 300 μCi of ³⁵S Easy Tag for 15 min and chased for 1 h. Labeled cells were fractionated, and the 4K supernatant was analyzed with floatation gradients (31). Each fraction was immunoprecipitated with an anti-WSN polyclonal antibody and analyzed by SDS–10% PAGE. Fractions are numbered 1 (top) to 5 (bottom). Lines marked 1 and 2 (upper right-hand corner) denote nonspecific cellular proteins. Both panels are from the same gel and same autoradiograph. (B) Pulse-chase analysis of RVVM1-infected HeLa cells. HeLa cells were infected with RVVM1 at an MOI of 10. At 6 hpi, cells were pulse-labeled with 400 μCi of ³⁵S Easy Tag and chased as described above, the 4K supernatant was analyzed with floatation gradients, and fractions were immunoprecipitated and analyzed by SDS-PAGE.