As a result, the HIV-1 ribosomal frameshift signal is highly regulated, as it modulates the expression levels of the Gag protein relative to the Gag-Pol polyprotein. The efficiency of the HIV-1 ribosomal frameshift signal determines the ratio of the Gag to Gag-Pol proteins synthesized, with a frameshift event occurring in approximately 5% of the total translation events, resulting in a roughly 20:1 Gag/Gag-Pol ratio. Preservation of this ratio has been shown to be essential to HIV-1 infectivity and structure, as even small changes in the efficiency of the frameshift lead to inhibition of viral propagation. The dependence of the HIV-1 virus on this ribosomal frameshift signal has generated interest in the frameshift as a target for novel antiviral therapeutics.