Figure 2.

Expression of dominant-negative Ras in CEF and Rat-2 cells. (A) CEF were infected with an envelope subgroup B empty vector virus or a similar virus encoding N17ras, and 2 days later were superinfected with an envelope subgroup A empty vector virus or a similar virus encoding v-src. Lysates were prepared 3 days after infection with the subgroup A virus and were subjected to immunoblotting for Src and Ras as described. (B) Rat-2 cell lines stably transfected with a vector encoding N17ras under the control of a metal-inducible promoter were infected with a retrovirus encoding v-src. Infected cell lines (Rat-2/pM2NSrc and Rat-2/N17RasSrc) and uninfected control cell lines (Rat-2/pM2N-1 and Rat-2/N17Ras-2) were grown in serum-containing medium in the absence or presence of 100 μM ZnCl₂ and 2 μM CdCl₂ for 24 hr, and then lysed and subjected to SDS/PAGE and immunoblotting as described.