The effect of cycloheximide on the replication of measles virus.

Treatment of measles virus-infected cells with cycloheximide results in a three-fold increase of 3H-uridine incorporation into the 12 to 36S mRNA species and in the inhibition of genomic 50S RNA synthesis. Consistent with these observations was the finding of a build-up of polyribosomes but an absence of nucleocapsids in the infected cells. These results suggest that measles virus RNA replication, but not transcription, is dependent upon active protein synthesis.