FIG. 5.

Cytoplasmic accumulation and transcription of viral L2 RNA. (A) Cytoplasmic L2 mRNAs were examined 18 h after infection by Northern blotting. Cells were infected with Ad5 or the E1B 55-kDa mutants listed, and the four L2 mRNAs and the human ribosomal protein 3 mRNAs were detected and quantified as described in Materials and Methods. Shown are penton and pre-Mu mRNA signals, corrected using the RpS3 mRNA internal control and expressed relative to the wild-type value, which was set at 1.0. Similar changes were observed in concentrations of the L2 V and pVII mRNAs. (B) Rates of L2 transcription were determined 18 h after infection of HeLa cells with Ad5 or the mutant viruses listed by run-on transcription in isolated nuclei and hybridization of the labeled RNA to membrane-immobilized L2 DNA. Signals were quantified and corrected as described in Materials and Methods and expressed relative to the wild-type value, which was set at 1.0. The values shown are the means of two independent experiments. Error bars show standard deviations.