FIG. 1.
Schematic diagram of the structure of genomic MIGCAT RNA and subgenomic MIGCAT RNA. The locations of leader sequences, an intergenic sequence, and CAT sequences are indicated. Oligonucleotides used for RT-PCR and the preparation of riboprobe 1, competitor A, and competitor B are shown by open arrowheads. T7 Pr, the T7 promoter sequence present at the 5′ ends of oligonucleotides 10319 and 10404. The short boldface line between the open arrowhead and the T7 promoter sequence in oligonucleotide 10319 represents a unique sequence that does not hybridize with either MIGCAT or MHV RNA sequences. Structures of probes used in the present study are also shown; the positions of riboprobe 1 and competitor A relative to genomic MIGCAT RNA and the positions of DNA probe 1 and competitor B relative to subgenomic MIGCAT RNA are shown. Riboprobe 1, competitor A, and competitor B are complementary to positive-strand MIGCAT-specific RNAs. Nucleotide numbers shown for these probes start from the beginning of the CAT sequence.