MicroRNAs in Human Immunodeficiency Virus-1 Infection

Initially reported for Caenorhabditis elegans , microRNA (miRNA) has been shown to regulate gene expression in plants, flies, and mammals (1 ,2 ). Recently, findings of miRNA have been extended to viruses (3 ,4 ). Here, we report on our approaches to investigate the role of miRNAs in human immunodeficiency virus (HIV)-1 infection. Using computer-directed foldings, we first identify potential sequences in HIV-1 that putatively encode miRNAs. Subsquently, we use Northern blotting of RNAs isolated from HIV-infected cells to confirm expression of predicted miRNA sequences. Finally, we use a scanning algorithm to search 3′ untranslated regions (UTRs) of human messenger RNAs (mRNAs) in the attempt to predict potential sites targeted by HIV-1 miRNAs.