Sequencing the cap-snatching repertoire of H1N1 influenza provides insight into the mechanism of viral transcription initiation.

ABSTRACT: The influenza polymerase cleaves host RNAs ∼10-13 nucleotides downstream of their 5' ends and uses this capped fragment to prime viral mRNA synthesis. To better understand this process of cap snatching, we used high-throughput sequencing to determine the 5' ends of A/WSN/33 (H1N1) influenza mRNAs. The sequences provided clear evidence for nascent-chain realignment during transcription initiation and revealed a strong influence of the viral template on the frequency of realignment. After accounting for the extra nucleotides inserted through realignment, analysis of the capped fragments indicated that the different viral mRNAs were each prepended with a common set of sequences and that the polymerase often cleaved host RNAs after a purine and often primed transcription on a single base pair

SUBMITTER: Koppstein D 

PROVIDER: S-EPMC4446424 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature