Table 2

Programmed −1 ribosomal frameshifting and M1 virus maintenance of strains harboring a single deletion of a UPF gene

Strain (genotype)% −1 ribosomal frameshifting*Killer maintenance
UPF+ (HFY1200)2.5+
upf1-Δ (HFY870)4.5+
upf2-Δ (HFY1300)3.9+
upf3-Δ (HFY861)8.4
  • * The −1 ribosomal frameshift efficiency (%) was determined by the ratio of β-gal activity in a strain harboring the −1 ribosomal frameshifting reporter plasmid to the activity in the same strain harboring the 0-frame control plasmid. 

  • L-AHN and M1 were introduced into the strains by cytoduction and the maintenance (+) or loss (−) of M1 dsRNA was analyzed by the killer plate assay and Northern blot analyses as described.