Hypersusceptibility mechanism of Tenofovir-resistant HIV to EFdA.
Hypersusceptibility mechanism of Tenofovir-resistant HIV to EFdA.
复制标题
DOI：
10.1186/1742-4690-10-65
复制
发表时间：
2013-06-24
期刊：
影响因子：
3.3
通讯作者：
Sarafianos SG
中科院分区：
文献类型：
--
作者：
Michailidis E;Ryan EM;Hachiya A;Kirby KA;Marchand B;Leslie MD;Huber AD;Ong YT;Jackson JC;Singh K;Kodama EN;Mitsuya H;Parniak MA;Sarafianos SG
人类免疫缺陷病毒1型（HIV-1）逆转录酶（RT）中的K65 R置换是接受一线抗逆转录病毒药物富马酸替诺福韦酯（TDF）治疗的患者中选择的主要耐药突变。4 '-乙炔基-2-氟-2'-脱氧腺苷（EFdA）是最有效的核苷类似物RT抑制剂（NRTI），与所有批准的NRTI不同，它保留了3 '-羟基，对野生型（WT）和耐药HIV具有显著的效力。EFdA主要作为链终止剂，在其并入新生DNA链后通过阻断易位起作用。EFdA处于临床前开发阶段，其对临床相关耐药HIV毒株的作用对于临床试验开始前设计最佳方案至关重要。在这里，我们报告说，K65 RT突变导致过敏EFdA。具体而言，在单复制循环实验中，我们发现EFdA阻断WT HIV的效率是TDF的十倍。在相同条件下，EFdA对K65 R HIV的抑制效率是TDF的70倍以上。我们确定了这种超敏反应的分子机制，使用酶的研究与WT和K65 R RT。这种取代引起较小的变化，EFdA掺入的效率相对于天然dATP底物，也在RT易位的效率后，将抑制剂掺入新生的DNA。然而，EFdA-MP从3'引物末端的切除效率的显著降低似乎是对抑制剂敏感性增加的主要原因。值得注意的是，突变的影响是DNA序列依赖性的。我们已经阐明了K65 R HIV对EFdA敏感的机制。我们的研究结果强调了EFdA改善针对TDF耐药HIV-1菌株的联合策略的潜力。
The K65R substitution in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is the major resistance mutation selected in patients treated with first-line antiretroviral tenofovir disoproxil fumarate (TDF). 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA), is the most potent nucleoside analog RT inhibitor (NRTI) that unlike all approved NRTIs retains a 3'-hydroxyl group and has remarkable potency against wild-type (WT) and drug-resistant HIVs. EFdA acts primarily as a chain terminator by blocking translocation following its incorporation into the nascent DNA chain. EFdA is in preclinical development and its effect on clinically relevant drug resistant HIV strains is critically important for the design of optimal regimens prior to initiation of clinical trials. Here we report that the K65R RT mutation causes hypersusceptibility to EFdA. Specifically, in single replication cycle experiments we found that EFdA blocks WT HIV ten times more efficiently than TDF. Under the same conditions K65R HIV was inhibited over 70 times more efficiently by EFdA than TDF. We determined the molecular mechanism of this hypersensitivity using enzymatic studies with WT and K65R RT. This substitution causes minor changes in the efficiency of EFdA incorporation with respect to the natural dATP substrate and also in the efficiency of RT translocation following incorporation of the inhibitor into the nascent DNA. However, a significant decrease in the excision efficiency of EFdA-MP from the 3’ primer terminus appears to be the primary cause of increased susceptibility to the inhibitor. Notably, the effects of the mutation are DNA-sequence dependent. We have elucidated the mechanism of K65R HIV hypersusceptibility to EFdA. Our findings highlight the potential of EFdA to improve combination strategies against TDF-resistant HIV-1 strains.
登录
查看更多内容
影响因子：
2.9
作者：
Arion, D;Kaushik, N;Parniak, MA
通讯作者：
Parniak, MA
影响因子：
4.9
作者：
Bazmi, HZ;Hammond, JL;Mellors, JW
通讯作者：
Mellors, JW
影响因子：
5.4
作者：
Götte, M;Arion, D;Wainberg, MA
通讯作者：
Wainberg, MA
影响因子：
4.9
作者：
Kodama, EI;Kohgo, S;Mitsuya, H
通讯作者：
Mitsuya, H
K65R突变在HIV-1逆转录酶聚合，切除拮抗和替诺福韦抗性中的作用的结构基础。
DOI：
10.1074/jbc.m109.022525
发表时间：
2009-12-11
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Das K;Bandwar RP;White KL;Feng JY;Sarafianos SG;Tuske S;Tu X;Clark AD Jr;Boyer PL;Hou X;Gaffney BL;Jones RA;Miller MD;Hughes SH;Arnold E
通讯作者：
Arnold E