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Abstract Potential G-quadruplex sites have been identified in the genomes of DNA and RNA viruses and proposed as regulatory elements. The genusOrthoflaviviruscontains arthropod-transmitted, positive-sense, single-stranded RNA viruses that cause significant human disease globally. Computational studies have identified multiple potential G-quadruplex sites that are conserved across members of this genus. Subsequent biophysical studies established that some G-quadruplexes predicted in Zika and tickborne encephalitis virus genomes can form and known quadruplex binders reduced viral yields from cells infected with these viruses. The susceptibility of RNA to degradation and the variability of loop regions have made structure determination challenging. Despite these difficulties, we report a high-resolution structure of the NS5-B quadruplex from the West Nile virus genome. Analysis reveals two stacked tetrads that are further stabilized by a stacked triad and transient noncanonical base pairing. This structure expands the landscape of solved RNA quadruplex structures and demonstrates the diversity and complexity of biological quadruplexes. We anticipate that the availability of this structure will assist in solving further viral RNA quadruplexes and provides a model for a conserved antiviral target inOrthoflavivirusgenomes.
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Potato virus X : A global potato‐infecting virus and type member of the Potexvirus genus
Abstract TaxonomyPotato virus Xis the type‐member of the plant‐infectingPotexvirusgenus in the familyAlphaflexiviridae. Physical propertiesPotato virus X (PVX) virions are flexuous filaments 460–480 nm in length. Virions are 13 nm in diameter and have a helical pitch of 3.4 nm. The genome is approximately 6.4 kb with a 5′ cap and 3′ poly(A) terminus. PVX contains five open reading frames, four of which are essential for cell‐to‐cell and systemic movement. One protein encodes the viral replicase. Cellular inclusions, known as X‐bodies, occur near the nucleus of virus‐infected cells. HostsThe primary host is potato, but it infects a wide range of dicots. Diagnostic hosts includeDatura stramoniumandNicotiana tabacum. PVX is transmitted in nature by mechanical contact. Useful websitehttps://talk.ictvonline.org/ictv‐reports/ictv_online_report/positive‐sense‐rna‐viruses/w/alphaflexiviridae/1330/genus‐potexvirus
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- Award ID(s):
- 1759034
- PAR ID:
- 10362612
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Plant Pathology
- Volume:
- 23
- Issue:
- 3
- ISSN:
- 1464-6722
- Format(s):
- Medium: X Size: p. 315-320
- Size(s):
- p. 315-320
- Sponsoring Org:
- National Science Foundation
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