220 Modulating the HIV-1 Replication Cycle Through RNAi Jean-Marc Jacque*, Mario Stevenson Prgm in Molecular Med, Univ of Massachusetts Med Sch, Worcester, MA, USA, 01605
Background: RNA interference (RNAi) is the process of sequence-specific, post-transcriptional gene silencing (PTGS) in animals and plants initiated by double-stranded RNA (dsRNA) that is homologous in sequence to the silenced gene. PTGS involves the generation of 21 to 26nt dsRNA fragments, generated by ribonuclease III cleavage from longer dsRNAs that specifically trigger mRNA destruction. Recent reports have shown that the use of chemically synthesized 21nt RNA nucleotides can induce PTGS in mammalian cells.
Method: We applied this technology to HIV-1 and show that viral infection and production can be specifically inhibited by RNA interference. This inhibition is achieved by specifically triggering degradation of the viral genome.
Results: By using 2 different molecular clones of HIV-1, differing in sequence by a few nucleotides, we show the high specificity of the phenomenon.
Conclusions: We show that we can modulate HIV-1 replication both at the level of genomic full-length RNA, influencing the production of viral particles, and at the level of spliced RNA species, influencing the production of HIV-1 proteins necessary for virus production. We have also developed vectors able to stably deliver dsRNAs into cells and induce PTGS that modulate infection and replication of HIV-1.
