FIG. 1.

M gene translational products synthesized in infected and M gene-transfected cells. (A) COS-1 cells mock infected (lane mock), infected with C/Yamagata/1/88 (lane Infect) at an MOI of 10 PFU/cell, or transfected with the transient expression vector pME18S, containing the full-length cDNA of the influenza C virus M gene (lane pME18S-CM), were labeled with [³⁵S]methionine for 60 min at 26 h p.i. or at 48 h p.t., and cell lysates were immunoprecipitated with anti-GST/CM2 serum (lane αCM2) or anti M1 MAb (L2) (lane αM1). The resulting immunoprecipitates were analyzed by SDS-PAGE on 17.5% gels containing 4 M urea under reducing conditions, followed by fluorography. The positions of molecular weight markers are shown to the left. (B) 293T cells mock transfected (lane mock) or transfected with an RNA polymerase I-driven vector containing influenza C virus M gene cDNA, pPolI/M, and plasmids expressing polymerases (PB2, PB1, and P3) and NP, pcDNA/PB2-AA, pcDNA/PB1-AA, pcDNA/P3-AA, and pCAGGS.MCS/NP-AA, respectively (20) (lane PolI-M), were labeled with [³⁵S]methionine for 60 min at 48 h p.t., and cell lysates were immunoprecipitated with anti-GST/CM2 serum (lane αCM2) or anti M1 MAb (L2) (lane αM1).