FIG. 4.

Northern analysis of Ty3 RNA. (A) Identification of RNA complexes in wild-type (WT) VLPs. RNA was isolated from VLP fractions containing 460 μg of protein (2, 22) and individual samples heated for 10 min at temperatures indicated. The RNA was separated on a 1% nondenaturing agarose gel, transferred to a GeneScreen Plus nylon membrane, and subjected to Northern analysis with a probe specific for the internal (non-LTR) region of Ty3. (B) Analysis of RNA complexes in IN-mutant VLPs. RNA was isolated from 20 μg of VLPs from WT or IN-mutant Ty3 and subjected to Northern analysis at 25°C, as described above. The monomeric and higher-order RNA species are indicated by arrows on the left. A denatured control RNA sample from wild-type VLPs was prepared as indicated in Panel A. Labels are as for Fig. 1.