FIG. 1.

(A) Diagram depicting the 3′RACE strategy employed throughout these studies for detection of L and M segment mRNAs. (B) Agarose gel results depicting the 3′RACE amplification of RVF virus L (left) and M (right) segment RNA species. Lane 1, virus-specific amplicons; lane 2, size marker. Full-length replication products (vcRNA) were detected for both L and M segments. However, in contrast to the case with the M segment, no smaller fragments corresponding to L segment mRNA species were observed. Similar results were obtained with both TOS and SFS viruses (data not shown). (C) Chromatogram sequence data indicating the exact sites of in vitro polyadenylation of L and M segment full-length vcRNA replication products, as indicated by arrows. Note that polyadenylation of the RVF virus L segment occurred only after the last genomic nucleotide at position 6404, indicating the lack of upstream mRNA termination. All nucleotide numbering is relative to the virus GenBank entry.