HIV-1 reverse transcriptase dissociates during strand transfer.
HIV-1 reverse transcriptase dissociates during strand transfer.
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HIV-1 逆转录酶在链转移过程中解离。
DOI：
10.1016/j.jmb.2011.07.055
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发表时间：
2011
影响因子：
5.6
通讯作者：
Bambara,RobertA
中科院分区：
文献类型：
--
作者：
Muchiri,JohnM;Rigby,SeanT;Nguyen,LauraA;Kim,Baek;Bambara,RobertA
人类免疫缺陷病毒1型（HIV-1）复制中发生在病毒中但不在宿主中的步骤是抗逆转录病毒治疗的优选靶点。链转移是独特的;由病毒逆转录酶（RT）产生的DNA链从一个RNA模板位置移动到另一个。理解该机制需要知道RT是否直接介导模板交换或在交换过程中解离，从而通过聚合物动力学发生。早期的体外研究表明，RT捕获聚合物的存在将允许在原始或供体模板上合成，但完全阻断转移和随后在第二或受体模板上的合成。一种解释是RT在转移过程中必须解离，但另一种解释是非聚合RT的螯合防止了链交换所需的供体模板的聚合无关的核糖核酸酶H（RNase H）裂解。为了解决这种模糊性，我们设计了一种引物模板系统，允许链转移没有RNase H活性。使用RNase H阴性突变体RT，我们表明，聚合物陷阱仍然阻止链转移。这证实了RT在链转移期间解离。促进链交换的HIV-1核衣壳蛋白的存在对这一结果几乎没有影响。另外的测定表明，野生型RT和含有延伸指状结构域的多核苷RT引物抗性HIV-1 RT（其特征在于其增强的引物-模板结合亲和力）都不能与捕获聚合物一起转移。这意味着RT之间的常见序列变异不太可能改变解离特征。
Steps in the replication of human immunodeficiency virus type 1 (HIV-1) occurring in the virus but not in the host are preferred targets of antiretroviral therapy. Strand transfer is unique; the DNA strand being made by viral reverse transcriptase (RT) is moved from one RNA template position to another. Understanding the mechanism requires knowing whether the RT directly mediates the template exchange or dissociates during the exchange, so that it occurs by polymer dynamics. Earlier work in vitro showed that the presence of an RT-trapping polymer would allow synthesis on the original or donor template but completely block transfer and subsequent synthesis on the second or acceptor template. One interpretation is that the RT must dissociate during transfer, but an alternative is that sequestration of non-polymerizing RTs prevents polymerization-independent ribonuclease H (RNase H) cleavages of the donor template necessary for strand exchange. To resolve this ambiguity, we designed a primer–template system that allows strand transfer without RNase H activity. Using an RNase H negative mutant RT, we showed that a polymer trap still prevented strand transfer. This confirms that RT dissociates during strand transfer. The presence of HIV-1 nucleocapsid protein, which promotes strand exchange, had little effect on this outcome. Additional assays showed that both the wild-type RT and a multiple nucleoside RT inhibitor-resistant HIV-1 RT containing an extended fingers domain, which is characterized by its enhanced primer–template binding affinity, were unable to transfer with the trapping polymer. This implies that common sequence variations among RTs are unlikely to alter dissociation feature.
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HIV-1 中央多嘌呤束区域的链置换合成促进 DNA 到 DNA 链转移重组*
影响因子：
4.8
作者：
G. M. Fuentes;C. Palaniappan;P. Fay;R. Bambara
通讯作者：
R. Bambara
有证据表明，入侵位点的产生决定了 HIV-1 逆转录酶介导的链转移速率。
影响因子：
5.6
作者：
Hanson,MarkNils;Balakrishnan,Mini;Roques,BernardP;Bambara,RobertA
通讯作者：
Bambara,RobertA
影响因子：
56.9
作者：
LARDER, BA;KEMP, SD
通讯作者：
KEMP, SD
影响因子：
5.6
作者：
Rose, Rebecca J.;Welsh, Thomas S.;Paci, Emanuele
通讯作者：
Paci, Emanuele
具有 1:1 比例的 p66 和 p51 亚基的 HIV-1 逆转录酶的纯化和表征。
影响因子：
1.6
作者：
M. Stahlhut;Y. Li;Jon H. Condra;J. Fu;Leah Gotlib;Donald J. Graham;David B. Olsen
通讯作者：
David B. Olsen