title: Terminal adenylation in the synthesis of RNA by Q beta replicase.
abstract: We investigated the apparent requirement that Q beta replicase must add a nontemplated adenosine to the 3' end of newly synthesized RNA strands. We used abbreviated MDV-1 (+)-RNA templates that lacked either 62 or 63 nucleotides at their 5' end in Q beta replicase reactions. The MDV-1 (-)-RNA strands synthesized from these abbreviated (+)-strand templates were released from the replication complex, yet they did not possess a nontemplated 3'-terminal adenosine. These results imply that, despite observations that all naturally occurring RNAs synthesized by Q beta replicase possess a nontemplated 3'-adenosine, the addition of an extra adenosine is not an obligate step for the release of completed strands. Since the abbreviated templates lacked a normal 5' end, it is probable that a particular sequence at the 5' end of the template is required for terminal adenylation to occur.
mesh_terms: D001483:Base Sequence; D003090:Coliphages / Q000201:enzymology*; D004926:Escherichia coli / Q000201:enzymology*; D014644:Genetic Variation; D007700:Kinetics; D009693:Nucleic Acid Hybridization; D011777:Q beta Replicase / Q000378:metabolism*; D012316:RNA Nucleotidyltransferases / Q000378:metabolism*; D012329:RNA, Bacterial / Q000235:genetics*; D013698:Templates, Genetic
chemical_list: D012329:RNA, Bacterial; D011777:Q beta Replicase; D012316:RNA Nucleotidyltransferases