Interaction of primer tRNALys3 with the p51 subunit of human immunodeficiency virus type 1 reverse transcriptase: a possible role in enzyme activation

[摘要]

In the interaction between HIV-1 RT and tRNA^Lys3 each subunit of the heterodimer interacts with tRNA showing a different affinity: K _d (p66) = 23 nM, K _d (p51) = 140 nM. Preincubation of heterodimeric RT with tRNA, at concentrations similar to that of the K _d value for p51, leads to an increase of the catalytic activity on poly(A)-oligo(dT). These results were compared to those using different tRNA analogs: oxidized tRNA, lacking one, two or three nucleotides from the 3′-end, or ribo- and deoxyribonucleotides mimicking the anticodon loop sequence. In all cases, tRNA analogs were weaker activators of HIV-1 RT than natural tRNA. A possible mechanism of RT p66/p51 activation by tRNA and its analogs, mediated through the p51 subunit, is discussed.

[学科分类] 生物化学/生物物理

[关键词] HIV-1 reverse transcriptase;tRNALys3 derivative;Enzyme activation;RT;Reverse transcriptase;HIV-1;Human immunodeficiency virus type 1;tRNA(−1);tRNA derivatives shortened by one;tRNA(−2);tRNA derivatives shortened by two;tRNA(−3);tRNA derivatives shortened by three nucleotides from the 3′-end