Deletions in the 3'-terminal tRNA-like structure of brome mosaic virus RNA differentially affect aminoacylation and replication in vitro.

Deletions in cDNA clones covering the 3' 201 nucleotides of brome mosaic virus RNA 3 were produced by S1 nuclease treatment of cloned DNA linearized at several different restriction sites. Transcription of these clones yielded RNAs containing structural alterations in the 3'-terminal tRNA-like structure that is involved in aminoacylation and replication. Replicase template activity, but not aminoacylation activity, was especially sensitive to deletions in arm C, which contains a tyrosyl anticodon. Deletions in arm B were detrimental to aminoacylation, but the proportion of replicase template activity lost depended on the site of the deletion. Removal of arm D had little effect on aminoacylation and, in some instances, resulted in a 2-fold stimulation of replicase template activity.