FIGURE 3.

Packaged snRNAs are reverse-transcribed by RSV in an endogenous RT reaction. (A) RSV virions were partially solubilized with detergent and incubated with dNTPs at 39°C for 4 h or placed immediately at −20.0°C. Media harvested from uninfected CEFs was used as the mock. Total nucleic acid was then harvested from the virions after the incubation and used as the template in a PCR reaction. Primer sets were used to detect the viral minus strand strong-stop, and DNA copies of U6, U1, U2, and U4 snRNAs. (B) The RSV, U6, U1, and U2 PCR products were restriction-digested to confirm their identities. RSV, U1, and U2 were digested with BstN1, and U6 was digested with MboII.