biostudies-literatureUnknown8(7)Monette ACanadian Institutes of Health ResearchThe precursor group-specific antigen (pr55(Gag)) is central to HIV-1 assembly. Its expression alone is sufficient to assemble into virus-like particles. It also selects the genomic RNA for encapsidation and is involved in several important virus-host interactions for viral assembly and restriction, making its synthesis essential for aspects of viral replication. Here, we show that the initiation of translation of the HIV-1 genomic RNA is mediated through both a cap-dependent and an internal ribosome entry site (IRES)-mediated mechanisms. In support of this notion, pr55(Gag) synthesis was maintained at 70% when cap-dependent translation initiation was blocked by the expression of eIF4G- and PABP targeting viral proteases in two in vitro systems and in HIV-1-expressing cells directly infectePloS onee68108https://www.ebi.ac.uk/biostudies/studies/S-EPMC3702555biostudies-literatureDual mechanisms of translation initiation of the full-length HIV-1 mRNA contribute to gag synthesis.PMC3702555Lopez-Lastra MMouland AJValiente-Echeverria FMonette ACohen EARivero MfalseDual mechanisms of translation initiation of the full-length HIV-1 mRNA contribute to gag synthesis.The precursor group-specific antigen (pr55(Gag)) is central to HIV-1 assembly. Its expression alone is sufficient to assemble into virus-like particles. It also selects the genomic RNA for encapsidation and is involved in several important virus-host interactions for viral assembly and restriction, making its synthesis essential for aspects of viral replication. Here, we show that the initiation of translation of the HIV-1 genomic RNA is mediated through both a cap-dependent and an internal ribosome entry site (IRES)-mediated mechanisms. In support of this notion, pr55(Gag) synthesis was maintained at 70% when cap-dependent translation initiation was blocked by the expression of eIF4G- and PABP targeting viral proteases in two in vitro systems and in HIV-1-expressing cells directly infecte2013-01-01T00:00:00Z20132026-04-08T16:33:23.485Z2026-04-08T06:33:58.991ZS-EPMC37025552386185510.1371/journal.pone.0068108