Combined IEM-ISH and double ISH performed on MHV-infected HeLa-MHVR cells at 5 hpi. (A) MHV ORF1a proteins detected by anti-D3 serum and secondary antibody coupled to 15-nm gold particles, and viral RNA detected by DIG-labeled riboprobe complementary to MHV gene 7 and anti-DIG antibody coupled to 10-nm gold particles localize to the same DMVs. (B) Subgenomic and genomic RNAs exist on the same DMVs. Probe 1, complementary to MHV gene 7 sequences, was detected using 10-nm-gold-tagged sheep anti-DIG antibody. Probe 2, complementary to a region of gene 1 sequences, was detected using 6-nm-gold-tagged antibiotin antibody. Some of the DMVs carrying both labels are indicated by arrowheads. Bars, 200 nm.