Slide into Action: Dynamic Shuttling of HIV Reverse Transcriptase on Nucleic Acid Substrates
Slide into Action: Dynamic Shuttling of HIV Reverse Transcriptase on Nucleic Acid Substrates
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DOI：
10.1126/science.1163108
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发表时间：
2008-11-14
期刊：
影响因子：
56.9
通讯作者：
Zhuang, Xiaowei
中科院分区：
文献类型：
--
作者：
Liu, Shixin;Abbondanzieri, Elio A.;Zhuang, Xiaowei
人类免疫缺陷病毒（HIV）的逆转录酶（RT）催化一系列反应，将单链病毒RNA转化为双链DNA，用于宿主细胞整合。该过程需要多种酶活性，包括 DNA 聚合、RNA 裂解、链转移和链置换合成。我们使用单分子荧光共振能量转移来实时探测 RT 和核酸底物之间的相互作用。观察到 RT 在核酸双链体上滑动，在双链体的相对末端之间快速穿梭。当到达 DNA 3' 末端时，RT 可以自发地转变为聚合方向。滑动动力学受到同源核苷酸和抗HIV药物的调节，它们分别稳定和不稳定聚合模式。这些长程易位活动促进逆转录途径的多个阶段，包括正常的DNA聚合和链置换合成。
The reverse transcriptase ( RT) of human immunodeficiency virus ( HIV) catalyzes a series of reactions to convert single- stranded viral RNA into double- stranded DNA for host cell integration. This process requires a variety of enzymatic activities, including DNA polymerization, RNA cleavage, strand transfer, and strand displacement synthesis. We used single- molecule fluorescence resonance energy transfer to probe the interactions between RT and nucleic acid substrates in real time. RT was observed to slide on nucleic acid duplexes, rapidly shuttling between opposite termini of the duplex. Upon reaching the DNA 3' terminus, RT can spontaneously flip into a polymerization orientation. Sliding kinetics were regulated by cognate nucleotides and anti- HIV drugs, which stabilized and destabilized the polymerization mode, respectively. These long- range translocation activities facilitate multiple stages of the reverse transcription pathway, including normal DNA polymerization and strand displacement synthesis.