Elucidating Molecular Mechanisms of Drug Resistance in HIV-1 Protease

阐明 HIV-1 蛋白酶耐药性的分子机制

基本信息

批准号：
8643268
负责人：
GAIL E FANUCCI
金额：
$ 26.71万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-04-01 至 2017-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8643268
关键词：
Accounting Acquired Immunodeficiency Syndrome Active Sites Antiviral Therapy Binding Country Crystallization Distal Drug Combinations Drug resistance Effectiveness Electron Spin Resonance Spectroscopy Electrons Enzyme Kinetics Enzymes Epidemic Evolution Generations Genetic Polymorphism Goals HIV HIV Infections HIV-1 Impairment Infection Kinetics Life Literature Measurement Measures Methods Modeling Molecular Molecular Conformation Mutation Nelfinavir Pathway interactions Patients Pattern Peptide Hydrolases Pharmaceutical Preparations Pharmacotherapy Physiologic pulse Play Point Mutation Population Positioning Attribute Predisposition Principal Investigator Process Protease Inhibitor Proteins Relative (related person)Relaxation Resistance Roentgen Rays Role Sampling Site Spectrum Analysis Spin Labels Structure Surgical Flaps Testing Variant Vertebral column Viral Work base design enzyme activity fitness flexibility inhibitor/antagonist innovation insight molecular dynamics novel pressure prevent programs public health relevance response

项目摘要

DESCRIPTION (provided by applicant): HIV-1 infection is a world-wide epidemic. Although current drug therapies are effective at extending patient life, infections continue to spread, especially in non-developed countries, and the emergence of drug resistance has limited the effectiveness of many protease inhibitors. The mechanism by which the evolution of accessory mutations in HIV-1 protease (HIV-1PR) act to recover enzymatic function while imparting cross resistance to numerous inhibitors is the focus of this proposal. We are proposing a novel mechanism, which evokes protein conformational sampling, as a molecular basis to explain how secondary mutations accomplish this task. Specifically we hypothesize that mutations combine in patterns that alter HIV-1PR conformational sampling among four nominal states; namely, the closed, the semi- open, curled/tucked and wide-open such that (1) enzyme function is recovered by the secondary mutations when they combine to stabilize the semi-open conformation to a percentage observed in a native enzyme (e.g. inhibitor naive sequence) and (2) that cross resistance emerges when the mutations combine to stabilize "open-like" states such as the wide-open and curled/tucked conformations while concomitantly destabilizing the closed state population. It is through an innovative application of pulsed electron paramagnetic spectroscopy, which our lab has pioneered over the last five years that we measure conformational sampling ensembles in HIV-1PR. Within the aims of this proposal, we will make correlations among changes in HIV-1PR conformational sampling ensembles to enzymatic parameters, inhibition constants, inhibitor susceptibility, and viral fitness for numerous HIV-1PR variants. From these results, if our hypothesis is correct, we will provide a molecular level understanding of how secondary mutations elicit their effects on HIV-1PR. Additionally, these studies will also provide insights into explaining why the patterns of secondary mutation evolution against protease inhibitors are divergent in non-B subtypes. Finally, we will target numerous variants that show cross-resistance and increased conformational sampling of the open-like states for structure determination. Structures with more open-like conformations can serve as targets for the rational design of the new inhibitors for treatment of extremely resistant HIV-1PR variants.

描述（由申请人提供）：HIV-1感染是全球流行病。尽管当前的药物疗法可有效地延长患者的寿命，但感染继续扩散，尤其是在未发育的国家，耐药性的出现限制了许多蛋白酶抑制剂的有效性。 HIV-1蛋白酶（HIV-1PR）中辅助突变演变在恢复酶促功能的同时，在众多抑制剂中恢复酶促功能的机制是该建议的重点。我们提出了一种新型机制，它唤起蛋白质构象采样，作为分子基础，以解释次级突变如何完成这项任务。具体而言，我们假设突变结合了改变四个名义状态之间HIV-1PR构象采样的模式。 namely, the closed, the semi- open, curled/tucked and wide-open such that (1) enzyme function is recovered by the secondary mutations when they combine to stabilize the semi-open conformation to a percentage observed in a native enzyme (e.g. inhibitor naive sequence) and (2) that cross resistance emerges when the mutations combine to stabilize "open-like" states such as the wide-open and卷曲/塞满的构象同时破坏了封闭的国家人口。通过创新的脉冲电子顺磁光谱法，我们的实验室在过去五年中率先进行了启发，我们测量了HIV-1PR中的构象采样集合。在该提案的目的中，我们将在HIV-1PR构象采样合奏中与酶参数，抑制常数，抑制剂敏感性和病毒适应性的变化之间的相关性，以实现许多HIV-1PR变体。从这些结果中，如果我们的假设正确，我们将提供分子水平的理解，以了解其二次突变如何引起其对HIV-1PR的影响。此外，这些研究还将提供有关解释为什么针对蛋白酶抑制剂的次级突变进化的模式在非B亚型中发散的。最后，我们将针对许多变体，这些变体显示出类似态状状态以确定结构状态的交叉抗性和增加的构象采样。具有更开放的构象的结构可以作为新抑制剂的合理设计的目标，以治疗极具耐药性 HIV-1PR变体。