Constraints on the evolution of influenza oseltamivir resistance

描述（由申请人提供）：本提案概述了Jesse D. Bloom博士的两年过渡资助。该资助将在Bloom博士开始在研究机构担任助理教授职位后启动，并将用于资助他最初几年的工作。Bloom博士目前是加州理工学院David Baltimore博士实验室的博士后学者。布鲁姆博士的研究考察了病毒进化中的分子限制。这一特殊的提议是通过神经氨酸酶蛋白的His274->Tyr （H274Y）突变来处理H1N1流感病毒对奥司他韦（达菲）耐药性的进化。这种抗性突变长期以来被认为不太可能传播，因为它减弱了季节性H1N1病毒，但它最近在世界范围内传播。Bloom博士的初步研究表明，H274Y的全球传播是通过继发性“允许”突变实现的，这种突变挽救了H274Y在神经氨酸酶蛋白表面表达中引起的缺陷。本研究将在组织培养和动物模型中详细研究H274Y引起的生物物理缺陷及其影响病毒生长的机制。为了帮助识别其他可能使H274Y进化传播的允许突变，该研究将开发和测试计算预测方法。最后，这些计算和实验工具将用于预测H274Y对猪源2009大流行H1N1流感毒株产生广泛奥司他韦耐药性的可能性。因此，拟议的工作将代表着朝着预测病毒进化的目标迈出了实质性的一步。实现这一目标的进展将对流感等医学上重要的病毒具有公共卫生价值。

DESCRIPTION (provided by applicant): This proposal outlines a two-year transitional grant for Jesse D. Bloom, Ph.D. The grant would be activated once Dr. Bloom begins an assistant professor position at a research institution, and would be used to fund the initial years of his work. Dr. Bloom is currently a postdoctoral scholar in the laboratory of Dr. David Baltimore at the California Institute of Technology. Dr. Bloom's research examines molecular constraints on viral evolution. This specific proposal deals with the evolution of oseltamivir (Tamiflu) resistance in H1N1 influenza viruses via the His274->Tyr (H274Y) mutation to the neuraminidase protein. This resistance mutation had long been thought unlikely to spread since it attenuated seasonal H1N1 viruses, but it recently spread worldwide. Dr. Bloom's preliminary research has shown that this global spread of H274Y was enabled by secondary "permissive" mutations that rescued a defect that H274Y caused in the surface expression of neuraminidase protein. The proposed research will examine in detail the biophysical defect caused by H274Y, and the mechanism by which it affects viral growth in tissue culture and animal models. In order to aid in the identification of other possible permissive mutations that might enable the evolutionary spread of H274Y, the research will develop and test computational prediction methods. Finally, these computational and experimental tools will be used towards forecasting the potential for H274Y to confer widespread oseltamivir resistance on the swine-origin 2009 pandemic H1N1 influenza strain. The proposed work will therefore represent a substantial step towards the goal of predicting virus evolution. Progress towards this goal will be of public health value in regards to medically important viruses such as influenza. Public Health Relevance: Viral diseases such as influenza are so problematic because they rapidly evolve to escape immunity and antiviral drugs. This proposal examines a specific example of viral escape, the evolution of oseltamivir (Tamiflu) resistance in H1N1 influenza. The goal is to understand this escape at a molecular level, and use the resulting insight to anticipate potential future routes of oseltamivir resistance.