The ribonucleic acids of the infective and interfering components of vesicular stomatitis virus.

Abstract

SUMMARY The RNA-containing components of vesicular stomatitis virus were labelled with 32P by growing the virus in a phosphate-deficient medium containing 32P04 and Actinomycin-D. Centrifugation of the virus suspensions in a sucrose gradient gave four radioactive fractions. The most rapidly sedimenting fraction contained the infective component of the virus, whereas most of the interfering activity was in the second fraction, which contained ‘caps’, filaments and rosette-like structures. The interfering activity was associated with the ‘cap’, which could be separated from the filaments and rosettes by centrifuging in a potassium tartrate gradient. The viral RNA sedimented predominantly in the 36 to 40 S position in sucrose gradients prepared in o-iM-acetate buffer but frequently exhibited a more heterogeneous profile. The percentage distribution of 32P in the four nucleotides was A = 29·3, C = 21·1, G = 20·9 and U = 28·7. Ribonucleic acid from the interfering component invariably gave a sharp profile with a sedimentation coefficient of 18 to 20 S and the percentage distribution of 32P was A = 27·1, C = 21·9, G = 20·3 and U = 30·7. Both nucleic acids were hydrolysed to low molecular weight materials by ribonuclease 0·01 µg./ml.