Decreasing the frameshift efficiency translates into an equivalent reduction of the replication of the human immunodeficiency virus type 1.
The Gag-Pol polyprotein of the human immunodeficiency virus type 1 (HIV-1) is the precursor of the virus enzymatic activities and is produced via a programmed -1 translational frameshift. In this study, we altered the frameshift efficiency by introducing mutations within the slippery sequence and the frameshift stimulatory signal, the two elements that control the frameshift. These mutations decreased the frameshift efficiency to different degrees, ranging from approximately 0.3% to 70% of the wild-type efficiency. These values were mirrored by a reduced incorporation of Gag-Pol into virus-like particles, as assessed by a decrease in the reverse transcriptase activity associated to these particles. Analysis of Gag processing in infectious mutant virions revealed processing defects to various extents, with no clear correlation with frameshift decrease. Nevertheless, the observed frameshift reductions translated into equivalently reduced viral infectivity and replication kinetics. Our results show that even moderate variations in frameshift efficiency, as obtained with mutations in the frameshift stimulatory signal, reduce viral replication. Therapeutic targeting of this structure may therefore result in the attenuation of virus replication and in clinical benefit.
Dulude
Dominic
D
Département de Biochimie, Université de Montréal, 2900 Boul. Edouard-Montpetit, Montréal, Québec, Canada H3T1J4.
Berchiche
Yamina A
YA
Gendron
Karine
K
Brakier-Gingras
Léa
L
Heveker
Nikolaus
N
D000595:Amino Acid Sequence; D015153:Blotting, Western; D018965:Frameshifting, Ribosomal; D015685:Fusion Proteins, gag-pol / Q000378:metabolism; D017930:Genes, Reporter; D016655:HIV Core Protein p24 / Q000032:analysis; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D008156:Luciferases / Q000032:analysis / Q000235:genetics; D008969:Molecular Sequence Data; D017354:Point Mutation; D011499:Protein Processing, Post-Translational; D012367:RNA, Viral / Q000235:genetics* / Q000502:physiology; D012194:RNA-Directed DNA Polymerase / Q000032:analysis; D014764:Viral Proteins / Q000032:analysis; D022701:Virosomes / Q000378:metabolism; D014779:Virus Replication / Q000235:genetics / Q000502:physiology*
D015685:Fusion Proteins, gag-pol; D016655:HIV Core Protein p24; D012367:RNA, Viral; D014764:Viral Proteins; D022701:Virosomes; D008156:Luciferases; D012194:RNA-Directed DNA Polymerase