Structural and biochemical basis for development of influenza virus inhibitors targeting the PA endonuclease.
Structural and biochemical basis for development of influenza virus inhibitors targeting the PA endonuclease.
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DOI：
10.1371/journal.ppat.1002830
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发表时间：
2012
期刊：
影响因子：
6.7
通讯作者：
White SW
中科院分区：
文献类型：
--
作者：
DuBois RM;Slavish PJ;Baughman BM;Yun MK;Bao J;Webby RJ;Webb TR;White SW
新出现的流感病毒对人类健康构成严重威胁，因为它们具有大流行的可能性。PA蛋白是开发新型抗流感药物的一个有希望的靶点，它的内切酶活性是病毒复制所必需的。宿主核糖体翻译病毒mRNAs需要对mRNAs封顶以进行识别和结合，所需的mRNA帽是由PA内切酶从宿主前mRNAs中切割或“抢走”的。利用PA催化域的最新晶体结构，基于结构的针对PA核酸内切酶的抑制剂的开发现在是可能的。在这项研究中，我们试图了解几种已知或预测可以阻断核酸内切酶依赖的聚合酶活性的化合物抑制作用的分子机制。利用体外核酸内切酶活性测定，我们发现这些化合物阻断了分离的PA核酸内切酶结构域的酶活性。利用X射线结晶学，我们展示了这些抑制剂是如何配位双金属核酸内切酶活性部位并与活性部位残基结合的。两种结构也揭示了抑制剂结合的诱导-匹配模式。通过这些结构，可以从分子上了解几种已知流感抑制剂的构效关系，以及PA突变产生耐药性的机制。综上所述，我们的数据揭示了基于结构的设计和优化PA核酸酶抑制剂的新策略。季节性流感和大流行性流感对全球公共卫生有巨大影响。对当前抗病毒疗法具有抗药性的流感病毒株迅速出现，突显出迫切需要开发新的治疗方案。一个有希望的药物发现目标是流感病毒PA蛋白，其内切酶活性对于病毒mRNAs转录的“帽子抢夺”步骤至关重要，该步骤允许转录物被宿主核糖体处理。在这里，我们描述了一种基于结构的分析，以小分子抑制流感病毒PA内切酶的机制。我们的X射线结晶学研究已经解决了已知和预测的抑制剂的结合模式，并揭示了它们直接阻断PA内切酶活性部位。我们还报告了一些有助于结合亲和力和特异性的分子相互作用。我们的结构结果得到了酶活性抑制的生化分析和计算对接实验的支持。总体而言，我们的数据揭示了针对PA蛋白的新型流感病毒抑制剂的设计和优化的令人兴奋的策略。
Emerging influenza viruses are a serious threat to human health because of their pandemic potential. A promising target for the development of novel anti-influenza therapeutics is the PA protein, whose endonuclease activity is essential for viral replication. Translation of viral mRNAs by the host ribosome requires mRNA capping for recognition and binding, and the necessary mRNA caps are cleaved or “snatched” from host pre-mRNAs by the PA endonuclease. The structure-based development of inhibitors that target PA endonuclease is now possible with the recent crystal structure of the PA catalytic domain. In this study, we sought to understand the molecular mechanism of inhibition by several compounds that are known or predicted to block endonuclease-dependent polymerase activity. Using an in vitro endonuclease activity assay, we show that these compounds block the enzymatic activity of the isolated PA endonuclease domain. Using X-ray crystallography, we show how these inhibitors coordinate the two-metal endonuclease active site and engage the active site residues. Two structures also reveal an induced-fit mode of inhibitor binding. The structures allow a molecular understanding of the structure-activity relationship of several known influenza inhibitors and the mechanism of drug resistance by a PA mutation. Taken together, our data reveal new strategies for structure-based design and optimization of PA endonuclease inhibitors. Seasonal and pandemic influenza have enormous impacts on global public health. The rapid emergence of influenza virus strains that are resistant to current antiviral therapies highlights the urgent need to develop new therapeutic options. A promising target for drug discovery is the influenza virus PA protein, whose endonuclease enzymatic activity is essential for the “cap-snatching” step of viral mRNA transcription that allows transcripts to be processed by the host ribosome. Here, we describe a structure-based analysis of the mechanism of inhibition of the influenza virus PA endonuclease by small molecules. Our X-ray crystallographic studies have resolved the modes of binding of known and predicted inhibitors, and revealed that they directly block the PA endonuclease active site. We also report a number of molecular interactions that contribute to binding affinity and specificity. Our structural results are supported by biochemical analyses of the inhibition of enzymatic activity and computational docking experiments. Overall, our data reveal exciting strategies for the design and optimization of novel influenza virus inhibitors that target the PA protein.
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影响因子：
3.7
作者：
Iwai Y;Murakami K;Gomi Y;Hashimoto T;Asakawa Y;Okuno Y;Ishikawa T;Hatakeyama D;Echigo N;Kuzuhara T
通讯作者：
Kuzuhara T
影响因子：
4.9
作者：
Hastings, JC;Selnick, H;Tomassini, JE
通讯作者：
Tomassini, JE
影响因子：
15
作者：
Hamelberg, D;McCammon, JA
通讯作者：
McCammon, JA
影响因子：
7.3
作者：
Kirschberg, Thorsten A.;Balakrishnan, Mini;Lansdon, Eric B.
通讯作者：
Lansdon, Eric B.
DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
Emsley, P;Cowtan, K
通讯作者：
Cowtan, K