FIG. 7.

RAF-2p48-mediated NP-RNA complex formation. ³²P-labeled RNA probe mixed with recombinant NP was incubated in the absence (lanes 1 to 12) or presence (lanes 13 to 24) of recombinant RAF-2p48. After 15 to 35% glycerol density gradient centrifugation, fractions were collected from the tops of the tubes. An aliquot of each fraction was analyzed by PAGE on a 5% polyacrylamide gel, and the RNA was visualized by autoradiography. The unbound RNA probe and NP-RNA complexes (lanes 5, 6, 17, and 18) are indicated by arrowheads. The bands shown in lanes 8 and 9 with less mobility than those in lanes 5, 6, 17, and 18 could be NP-RNA complexes containing more than one NP molecule per RNA molecule.