Location: National Germplasm Resources LaboratoryTitle: Completion of Maize Stripe Virus genome sequence and analysis of diverse isolates across two continents
|BRAITHWAITE, KATHRYN - Sugar Research Australia
|BEIRIGER, ROBERT - University Of Florida
|FALK, BRYCE - University Of California, Davis
Submitted to: Frontiers in Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/26/2021
Publication Date: 6/14/2021
Citation: Bolus, S.J., Braithwaite, K., Grinstead, S.C., Fuentes-Bueno, I., Beiriger, R., Falk, B., Mollov, D.S. 2021. Completion of Maize Stripe Virus genome sequence and analysis of diverse isolates across two continents. Frontiers in Microbiology. https://doi.org/10.3389/fmicb.2021.684599.
Interpretive Summary: Maize stripe virus (MSpV) is a pathogen of corn, sorghum, and other grasses in subtropical and tropical regions worldwide. It is comprised of RNA encapsidated as long, filamentous particles. We used high-throughput sequencing to complete the RNA genomic sequences of a total of 11 MSpV isolates from two continents, United States (US) and Papua New Guinea (PNG), and two host plants, maize and itchgrass. We determined that there is significant diversity among MSpV isolates, although with some grouping based on geography. In PNG, both maize and itchgrass isolates were closely related, supporting the possibility that the latter (a noxious weed in the U.S.) may be a reservoir form which infections spread into production crops. The viral genome is segmented among 4-5 RNA strands, depending on the isolate, and comparisons among them can provide information about how the virus has evolved and new strains emerged. This publication provides foundational work that will support future research into MSpV and related virus taxonomy, diagnostics, disease management, and molecular evolution.
Technical Abstract: Maize stripe virus is a pathogen of corn and sorghum in subtropical and tropical regions worldwide. We used high-throughput sequencing to obtain the complete nucleotide sequence for the reference genome of maize stripe virus and to sequence the genomes of ten additional isolates collected from the United States or Papua New Guinea. Genetically, maize stripe virus is most closely related to rice stripe virus. We completed and characterized the RNA1 sequence for maize stripe virus, which revealed a large open reading frame encoding ovarian tumor-like cysteine protease, endonuclease, and RNA-dependent RNA polymerase domains. Phylogenetic comparisons and amino acid identity analyses among geographically diverse isolates revealed evidence for reassortment in RNA3 that was correlated with the absence of RNA5. This study yielded a complete and updated genetic description of the tenuivirus maize stripe virus and provided insight into potential mechanisms underpinning its diversity.