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High-frequency leader sequence switching during coronavirus defective interfering RNA replication.

S Makino·M M Lai
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Abstract

A system was developed that exploited defective interfering (DI) RNAs of coronavirus to study the role of free leader RNA in RNA replication. A cDNA copy of mouse hepatitis virus DI RNA was placed downstream of the T7 RNA polymerase promoter to generate DI RNAs capable of extremely efficient replication in the presence of a helper virus. We demonstrated that, in the DI RNA-transfected cells, the leader sequence of these DI RNAs was switched to that of the helper virus during one round of replication. This high-frequency leader sequence exchange was not observed if a nine-nucleotide stretch of sequence (UUUAUAAAC) at the junction between the leader and the remaining DI sequence was deleted. This observation suggests that a free leader RNA generated from the genomic RNA of mouse hepatitis virus may participate in the replication of DI RNA.

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Base SequenceCloning, MolecularCoronaviridaeDefective VirusesHelper VirusesMolecular Sequence DataMurine hepatitis virusOligonucleotide ProbesPlasmidsRNA, MessengerRNA, ViralRestriction MappingTranscription, GeneticTransfectionJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

S Makino, M M Lai. 1989. High-frequency leader sequence switching during coronavirus defective interfering RNA replication.. https://doi.org/10.1128/jvi.63.12.5285-5292.1989

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