Robert D, Sallafranque-Andreola M L, Bordier B, Sarih-Cottin L, Tarrago-Litvak L, Graves P V, Barr P J, Fournier M, Litvak S
Institut de Biochimie Cellulaire et Neurochimie du CNRS, Bordeaux, France.
FEBS Lett. 1990 Dec 17;277(1-2):239-42. doi: 10.1016/0014-5793(90)80855-d.
Retroviral RNA-dependent DNA polymerase (reverse transcriptase or RT) uses the 3'OH end of a cellular tRNA as primer to initiate DNA synthesis. Previous work with avian retrovirus has shown that reverse transcriptase is implicated in the selection of cellular virion-encapsidated tRNAs and has shown that the primer tRNA is positioned on the primer binding site near the 5' end of the viral RNA. These mechanisms support the idea that the retroviral polymerase should form complexes with primer tRNA and the specific encapsidated ones. The genomic sequence of human immunodeficiency virus (HIV) allows the prediction that tRNA(Lys3) is the natural primer. In this article we show, using the mobility shift assay, that recombinant HIV reverse transcriptase is able to form a complex with bovine tRNA(Lys.) By fluorescence studies and alpha-chymotrypsin analysis we have observed a modification of the enzyme conformation when reverse transcriptase is bound to the putative primer tRNA. This structural change is specific for tRNA(Lys) although the retroviral polymerase is able to interact with other tRNAs.
逆转录病毒RNA依赖性DNA聚合酶（逆转录酶或RT）利用细胞tRNA的3'OH末端作为引物来启动DNA合成。先前对禽逆转录病毒的研究表明，逆转录酶与细胞内病毒体包裹的tRNA的选择有关，并且表明引物tRNA位于病毒RNA 5'端附近的引物结合位点上。这些机制支持了逆转录病毒聚合酶应与引物tRNA和特定包裹的tRNA形成复合物的观点。人类免疫缺陷病毒（HIV）的基因组序列预测tRNA（Lys3）是天然引物。在本文中，我们使用迁移率变动分析表明，重组HIV逆转录酶能够与牛tRNA（Lys.）形成复合物。通过荧光研究和α-胰凝乳蛋白酶分析，我们观察到当逆转录酶与推定的引物tRNA结合时，酶的构象发生了改变。尽管逆转录病毒聚合酶能够与其他tRNA相互作用，但这种结构变化对tRNA（Lys）是特异性的。
