FIG. 1.

MHV68 ORF 45 is transcribed at an early-late stage of virus lytic replication. BHK-21 cells were infected with MHV68 at an MOI of 5 in the absence (−) or presence of cycloheximide (c) or phosphonoacetic acid (p). Total cellular RNA was harvested at the indicated times postinfection (p.i.), as shown at the top of the panels, and analyzed by Northern blotting. The membrane was sequentially hybridized with probes to ORF 45, M3, GAPDH (providing a loading control), and Rta. Arrows indicate major transcripts of ORF 45, M3, Rta, and GAPDH. The sizes of RNA ladder are indicated on the right.