Comparisons among Satellite RNA Species from Five Isolates of Tomato Black Ring Virus and One Isolate of Myrobalan Latent Ringspot Virus

The satellite RNA species from five isolates of tomato black ring virus (TBRV), belonging to two serotypes, and one isolate of myrobalan latent ringspot virus (MLRV) were compared. Each was translated in wheat germ extracts to give a single prominent polypeptide of mol. wt. 48000 (TBRV satellites) or 45000 (MLRV satellite). Analysis of the translation products by peptide mapping, and of the satellite RNA molecules by oligonucleotide mapping, showed that the MLRV satellite RNA was distinct from any of the others. The TBRV satellites had some similarities to each other but were of two types that differed in nucleotide sequence and that were associated with TBRV helper isolates of the different serotypes.