title: The flavivirus-conserved penta-nucleotide in the 3' stem-loop of the West Nile virus genome requires a specific sequence and structure for RNA synthesis, but not for viral translation.
abstract: A reporting replicon of West Nile virus (WN) was used to distinguish between the function of the 3' untranslated region (UTR) in viral translation and RNA replication. Deletions of various regions of the 3' UTR of the replicon did not significantly affect viral translation, but abolished RNA replication. A systematic mutagenesis showed that the flavivirus-conserved penta-nucleotide (5'-CACAG-3' located at the top of the 3' stem-loop of the genome) requires a specific sequence and structure for WN RNA synthesis, but not for viral translation. (i) Basepair structure and sequence at the 1st position of the penta-nucleotide are critical for RNA replication. (ii) The conserved nucleotides at the 2nd, 3rd, and 5th positions, but not at the 4th position of the penta-nucleotide, are essential for RNA synthesis. (iii) The nucleotide U (which is partially conserved in the genus Flavivirus) immediately downstream of the penta-nucleotide is not essential for viral replication.
authors.affiliation: New York State Department of Health, Wadsworth Center, Albany, NY 12208, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Tilgner
authors.forename: Tia S
authors.initials: TS
authors.lastname: Deas
authors.forename: Pei-Yong
authors.initials: PY
authors.lastname: Shi
mesh_terms: D017124:Conserved Sequence; D016679:Genome, Viral; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000235:genetics; D012367:RNA, Viral / Q000032:analysis / Q000096:biosynthesis*; D014779:Virus Replication; D014902:West Nile virus / Q000235:genetics* / Q000502:physiology
chemical_list: D012367:RNA, Viral