FIG. 4.

(A) The sequences of O3S1B and O3S2B are shown above and below, respectively, the wt O3 stem. Nucleotides differing from those of the wt sequence are highlighted. (B) RNase protection analysis to determine the amount of neo RNA packaged in virions released from G418-resistant mass cultures of Q2bn-4D cells transfected with plasmids, as indicated above each lane, and annealed to the antisense neo probe. The expected locations of free probe and the protected neo band are indicated by arrows. No RNase was added to the sample in lane 10.