HYBRID TY1 HIV-1 ELEMENTS USED TO DETECT INHIBITORS AND MONITOR THE ACTIVITY OF HIV-1 REVERSE-TRANSCRIPTASE/

We previously demonstrated that hybrid retrotransposons composed of th e yeast Ty1 element and the reverse transcriptase (RT) of HIV-1 are ac tive in the yeast Saccharomyces cerevisiae. The RT activity of these h ybrid Ty1/HIV-1 (his3A1/AIDS RT; HART) elements can be monitored by us ing a simple genetic assay. HART element reverse transcription depends on both the polymerase and RNase H domains of HIV-1 RT. Here we demon strate that the HART assay is sensitive to inhibitors of HIV-1 RT. (-) -tetrahydro-5-methyl-6-(3-methyl-2-butenyl)imidazo [4,5,1-jk][1,4] -b enzodiazepin-2 (1H)-thione monohydrochloride (8 Cl-TIBO), a well chara cterized non-nucleoside RT inhibitor (NNRTI) of HIV-1 RT, blocks propa gation of HART elements. HART elements that express NNRTI-resistant RT variants of HIV-1 are insensitive to 8 Cl-TIBO, demonstrating the spe cificity of inhibition in this assay, HART elements carrying NNRTI-res istant variants of HIV-1 RT can be used to identify compounds that are active against drug-resistant viruses.