IN-VIVO REPAIR OF 3'-END DELETIONS IN A TCV SATELLITE RNA MAY INVOLVE2 ABORTIVE SYNTHESIS AND PRIMING EVENTS

RNA viruses that do not have the stabilizing features of poly(A) tails or amino acids covalently linked to their 3' ends must develop other means for protecting or repairing their genomes from damage caused by cellular RNases. We previously round that deletions in the single-stra nded tails of a satellite RNA (sat-RNA D) associated with turnip crink le virus are repaired in vivo (C. D. Carpenter and A E. Simon, 1996, J . Virol. 70, 478-486). We now extend this analysis to show that sat-RN A D transcripts with 3'-end deletions of 5 bases give rise to wild-typ e sat-RNA, white deletions of 6 to 11 bases result in sat-RNA with add itional deletions to the -14 position joined to internal TCV genomic R NA (or other) sequence followed by replacement of the terminal C(1-2)U GC(1-3) motif. In addition, we have determined that the selection of i nternal TCV sequence used in the repair of sat-RNA D 3' ends is not ra ndom and generation of these short TCV segments likely involves primer -mediated synthesis of abortive products facilitated by base-pairing b etween internal regions of TCV genomic RNA and oligoribonucleotides ge nerated by abortive cycling from the 3' end of the TCV genome. (C) 199 6 Academic Press, Inc.