FIG. 5.

In vitro translation kinetics of wild-type (wt) and Δ3′ NCR transcript RNAs. Translation and processing were carried out in HeLa cell extracts at 30°C in the presence of [³⁵S]methionine. Extracts were incubated with PV1 virion RNA (lane 1) or no RNA (lane 2) for 4 h. At the indicated times, 10-μl portions of the extracts incubated with pT7-PV1-derived transcripts (lanes 3 to 8) or pT7PVΔ3′NCR-derived transcripts (lanes 9 to 14) were removed and translation was terminated by the addition of Laemmli sample buffer (31) and boiling for 3 to 5 min. These products were analyzed on an SDS-2.5% polyacrylamide gel and visualized by phosphorimager (Personal Molecular Imager FX; Bio-Rad, Hercules, California).