Lai Ming-Tain, Munshi Vandna, Lu Meiqing, Feng MeiZhen, Hrin-Solt Renee, McKenna Philip M, Hazuda Daria J, Miller Michael D
Department of Antiviral Research, Merck Research Laboratories, West Point, PA 19486, USA.
Viruses. 2016 Sep 23;8(10):263. doi: 10.3390/v8100263.
Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are a mainstay of therapy for human immunodeficiency type 1 virus (HIV-1) infections. However, their effectiveness can be hampered by the emergence of resistant mutations. To aid in designing effective NNRTIs against the resistant mutants, it is important to understand the resistance mechanism of the mutations. Here, we investigate the mechanism of the two most prevalent NNRTI-associated mutations with K103N or Y181C substitution. Virus and reverse transcriptase (RT) with K103N/Y188F, K103A, or K103E substitutions and with Y181F, Y188F, or Y181F/Y188F substitutions were employed to study the resistance mechanism of the K103N and Y181C mutants, respectively. Results showed that the virus and RT with K103N/Y188F substitutions displayed similar resistance levels to the virus and RT with K103N substitution versus NNRTIs. Virus and RT containing Y181F, Y188F, or Y181F/Y188F substitution exhibited either enhanced or similar susceptibility to NNRTIs compared with the wild type (WT) virus. These results suggest that the hydrogen bond between N103 and Y188 may not play an important role in the resistance of the K103N variant to NNRTIs. Furthermore, the results from the studies with the Y181 or Y188 variant provide the direct evidence that aromatic π-π stacking plays a crucial role in the binding of NNRTIs to RT.
非核苷类逆转录酶抑制剂（NNRTIs）是治疗人类免疫缺陷病毒1型（HIV-1）感染的主要药物。然而，耐药突变的出现会阻碍其疗效。为了辅助设计针对耐药突变体的有效NNRTIs，了解突变的耐药机制很重要。在此，我们研究了两种最常见的与NNRTIs相关的K103N或Y181C替代突变的机制。分别使用具有K103N/Y188F、K103A或K103E替代以及具有Y181F、Y188F或Y181F/Y188F替代的病毒和逆转录酶（RT）来研究K103N和Y181C突变体的耐药机制。结果显示，具有K103N/Y188F替代的病毒和RT与具有K103N替代的病毒和RT对NNRTIs的耐药水平相似。与野生型（WT）病毒相比，含有Y181F、Y188F或Y181F/Y188F替代的病毒和RT对NNRTIs表现出增强或相似的敏感性。这些结果表明，N103和Y188之间的氢键可能在K103N变体对NNRTIs的耐药性中不起重要作用。此外，对Y181或Y188变体的研究结果提供了直接证据，表明芳香族π-π堆积在NNRTIs与RT的结合中起关键作用。
