CAGE sequencing of LASV infected Vero Cells

We report a novel mechanism of gene origination in the segmented negative sense viruses (sNSVs), including IAV and LASV. During replication, these viruses use "snatched" host caps to prime their own transcription (cap-snatching). We show that a proportion of cap-snatched host sequences contain translational start codons (AUGs), that are recognized by the host ribosome. This allows for the translation of host and viral “untranslated regions” (UTRs) to create N-terminally extended viral proteins or entirely novel polypeptides by genetic overprinting. CAGE sequencing of LASV infected Vero cells was used to determine if cap-snatching events in LASV infected cells gave rise to chimeric host-virus RNAs that had upstream AUGs.