Coordinate Roles of Gag and RNA Helicase A in Promoting the Annealing of tRNA3 Lys to HIV-1 RNA
نویسندگان
چکیده
RNA helicase A (RHA) has been shown to promote HIV-1 replication at both the translation and reverse transcription stages. A prerequisite step for reverse transcription involves the annealing of tRNA3 , the primer for reverse transcription, to HIV-1 RNA. tRNA3 Lys annealing is a multistep process that is initially facilitated by Gag prior to viral protein processing. Herein, we report that RHA promotes this annealing through increasing both the quantity of tRNA3 Lys annealed by Gag and the ability of tRNA3 Lys to prime the initiation of reverse transcription. This improved annealing is the result of an altered viral RNA conformation produced by the coordinate action of Gag and RHA. Since RHA has been reported to promote the translation of unspliced viral RNA to Gag protein, our observations suggest that the conformational change in viral RNA induced by RHA and newly produced Gag may help facilitate the switch in viral RNA from a translational mode to one facilitating tRNA3 Lys annealing.
منابع مشابه
Coordinate roles of Gag and RNA helicase A in promoting the annealing of tRNA Lys3 to HIV-1 RNA
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