Effects of tRNA_3~(Lys) aminoacylation on the initiation of HIV-1 reverse transcription

摘要

HIV-1 utilizes cellular tRNA_3~(Lys) to prime the initiation of reverse transcription. The selective incorporation of cytoplasmic tRNA_3~(Lys) into HIV-1 particles was recently shown to involve the lysyl-tRNA synthetase, and hence, the encapsidated tRNA_3~(Lys) is likely to be aminoacylated. Here, we tested the effect of aminoacylation on the initiation of reverse transcription. We show that HIV-1 reverse transcriptase is unable to extend lysyl-tRNA_3~(Lys). In addition, the viral polymerase does not significantly enhance the rate of tRNA deacylation, in contrast with previous studies on avian retroviruses. Thus, aminoacylation of the primer tRNA might prevent the initiation of HIV-1 reverse transcription from taking place before viral budding and maturation.