RESPIRATORY VIRUS ION CHANNELS

呼吸道病毒离子通道

基本信息

批准号：
6510633
负责人：
LAWRENCE H PINTO
金额：
$ 19.45万
依托单位：
NORTHWESTERN UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1993
资助国家：
美国
起止时间：
1993-04-01 至 2003-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6510633
关键词：
Orthomyxoviridae Xenopus Xenopus oocyte acidity /alkalinity amantadine copper cysteine drug resistance gene mutation influenzavirus A ion transport membrane channels protein structure function tissue /cell culture virus infection mechanism virus protein voltage /patch clamp zinc

项目摘要

During an average year, 10-20 percent of the US population becomes infected with influenza virus, but the only antiviral treatment available for those infected with influenza A virus is rimantadine, the target for which is the M2 ion channel protein. More effective inhibitors of the channel are needed because rimantadine-resistant mutants are generated rapidly. In the previous grant period we found that inhibition of the channel occurs when the pH of the cytoplasmic domain is lowered and transition metal complexes are formed with the M2 molecule. We propose to determine the mechanism for these inhibitions in order to identify new targets for drug action on the M2 molecule. From functional measurements we have found that the active state of the M2 ion channel is a homotetramer and we have identified residues that line the channel pore. We propose to determine the structure of the molecule with direct measurements because this structural information will allow for the design of more useful inhibitors. The individual aims are: 1. To understand the mechanism for inhibition of M2 ion channel as a result of decreased pH of the C-terminal domain. 2. To determine the M2 ion channel pore structure with the substituted cysteine accessibility method. 3. To use transition metal complexes to probe the pore structure of the M2 ion channel. 4. To apply the approach of site-directed spin labeling of the M2 ion channel transmembrane domain to determine its resting structure and structural changes that occur on activation by low pH. 5. To understand the role of transmembrane histidine 37 in proton transport by the M2 ion channel. 6. In a separate set of experiments we will test the hypothesis that the NB protein of influenza B virus functions as an ion channel.

平均每年，10-20% 的美国人口成为感染流感病毒，但唯一的抗病毒治疗对于甲型流感病毒感染者，可以使用金刚乙胺，其目标是 M2 离子通道蛋白。更有效需要通道抑制剂，因为金刚乙胺耐药突变体迅速产生。在之前的资助期内我们发现当细胞质的 pH 值降低时，就会发生通道的抑制域降低并与M2形成过渡金属络合物分子。我们建议确定这些抑制的机制以确定药物作用于 M2 分子的新靶点。从功能测量中我们发现，活性状态 M2 离子通道是同源四聚体，我们已经鉴定出残基排列通道孔。我们建议确定分子可以直接测量，因为这种结构信息将允许设计更有用的抑制剂。个人目的是： 1. 了解M2离子的抑制机制 C 端结构域 pH 值降低的结果。 2. 到确定 M2 离子通道孔结构半胱氨酸可及性方法。 3. 利用过渡金属配合物探测 M2 离子通道的孔隙结构。 4. 应用该方法 M2 离子通道跨膜的定点自旋标记域来确定其静止结构和结构变化低 pH 值激活时发生。 5.了解角色的作用 M2 离子通道质子运输中的跨膜组氨酸 37。 6. 在一组单独的实验中，我们将检验以下假设：乙型流感病毒的NB蛋白起到离子通道的作用。