Beet Necrotic Yellow Vein Virus Noncoding RNA Production Depends on a 5′→3′ Xrn Exoribonuclease Activity

Autor: Alyssa Flobinus, Nicolas Chevigny, Phillida A. Charley, Tanja Seissler, Elodie Klein, Claudine Bleykasten-Grosshans, Claudio Ratti, Salah Bouzoubaa, Jeffrey Wilusz, David Gilmer
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Viruses, Vol 10, Iss 3, p 137 (2018)
Druh dokumentu: article
ISSN: 1999-4915
DOI: 10.3390/v10030137
Popis: The RNA3 species of the beet necrotic yellow vein virus (BNYVV), a multipartite positive-stranded RNA phytovirus, contains the ‘core’ nucleotide sequence required for its systemic movement in Beta macrocarpa. Within this ‘core’ sequence resides a conserved “coremin” motif of 20 nucleotides that is absolutely essential for long-distance movement. RNA3 undergoes processing steps to yield a noncoding RNA3 (ncRNA3) possessing “coremin” at its 5′ end, a mandatory element for ncRNA3 accumulation. Expression of wild-type (wt) or mutated RNA3 in Saccharomyces cerevisiae allows for the accumulation of ncRNA3 species. Screening of S. cerevisiae ribonuclease mutants identified the 5′-to-3′ exoribonuclease Xrn1 as a key enzyme in RNA3 processing that was recapitulated both in vitro and in insect cell extracts. Xrn1 stalled on ncRNA3-containing RNA substrates in these decay assays in a similar fashion as the flavivirus Xrn1-resistant structure (sfRNA). Substitution of the BNYVV-RNA3 ‘core’ sequence by the sfRNA sequence led to the accumulation of an ncRNA species in yeast in vitro but not in planta and no viral long distance occurred. Interestingly, XRN4 knockdown reduced BNYVV RNA accumulation suggesting a dual role for the ribonuclease in the viral cycle.
Databáze: Directory of Open Access Journals
Nepřihlášeným uživatelům se plný text nezobrazuje