Polyadenylate in the RNA of Five Nepoviruses

Abstract

RNA extracted from particles of 5 nepoviruses [raspberry ringspot (RRV), strawberry latent ringspot, tobacco ringspot (TRSV), tomato black ring (TBRV) and tomato ringspot viruses] was bound to oligo(dT)-cellulose in buffers of high ionic strength (HS) whereas RNA from particles of tobacco mosaic virus or tobacco rattle virus was not. This suggests that nepovirus RNA molecules contain polyadenylate [poly(A)]. At least 97% of the infective RNA molecules of TRSV and TBRV were bound in HS buffer and eluted in buffer of low ionic strength. The 2 species of genome RNA of RRV and TBRV were bound equally to oligo(dT)-cellulose, but the satellite RNA (RNA-3) of TBRV was bound less avidly and to a smaller extent than the genome RNA. When 3H-borohydride-labeled TRSV RNA was digested with RNases A + T1, about 29% of the radioactivity bound to oligo(dT)-cellulose, presumably as polyadenylate. Adenosine trialcohol was the only nucleoside trialcohol detected in alkali digests of borohydride-labeled RNA. Thus, polyadenylate is probably located at the 3''-termini of the RNA molecules.