EARLY STAGES OF INFECTION BY NONENVELOPED VIRUSES

无包膜病毒感染的早期阶段

• 批准号: 6170927
• 负责人: Marie Chow
• 金额: $ 31.16万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-30 至 2003-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6170927
• 关键词: antibody receptor; artificial membranes; capsid; intracellular transport; membrane channels; membrane permeability; poliovirus; polymerase chain reaction; protein purification; receptor binding; receptor expression; virus RNA; virus infection mechanism; virus receptors

DESCRIPTION: Characterization of human poliovirus receptor (PVR) has led to a detailed description of the initial stage of the entry process, the virus-receptor interaction. However, kinetic and genetic evidence also indicate the existence of additional stages which involve membrane interactions and remain poorly understood. In this revised application, Dr. Chow at the University of Arkansas and her collaborator, Dr. M. Tosteson at Harvard, will evaluate two plausible models of RNA delivery into the cytoplasm. Both models require that the native (160S) particles interact with PVR to generate an "entry-active" particle and that this altered particle interacts with host cell membranes. The simplest model proposes that, after PVR interaction, only the RNA genome is transported directly across the plasma membrane through virus-specific ion-permeable channels. The second model involves the passage of the "delivery active" virus particle across the membrane into the cytoplasm and subsequent release of the RNA from the particle. To dissect these early events, the proposed studies will build on Drs. Chow and Tosteson's recent observation that entry competent viruses produce ion-permeable channels in model membranes. In the first Aim, the applicants propose to characterize conductance, kinetic characteristics and lumen size of the channels. They will also separately determine the effects on channel formation of docking the virus particles using the PVR versus using an Fc receptor with antibody coated particles. They also will monitor effects induced in the particle's channel forming properties from binding Win drugs or peptide specific antibodies. The second Aim will characterize the capsid protein domains involved in membrane interaction and define their roles in virus entry. Existing and newly constructed mutants in VP4 or in the N-terminus of VP1 defective in entry will be examined using model membranes for any changes in channel properties; if found, these will be correlated with biological phenotypes. It is aticipated that the studies will provide the biochemical and biophysical make-up of the channel structure and allow the applicants to build a general model of the early stages of infection by nonenveloped viruses.

描述：人类脊髓灰质炎病毒受体 (PVR) 的表征导致 进入过程的初始阶段的详细描述， 病毒-受体相互作用。 然而，动力学和遗传证据也 表明存在涉及膜的附加阶段 相互作用并且仍然知之甚少。 在这个修改后的申请中，博士。 阿肯色大学的 Chow 和她的合作者，M. Tosteson 博士 哈佛大学将评估两种可能的 RNA 递送模型 细胞质。 两种模型都需要原生 (160S) 粒子相互作用 使用 PVR 生成“进入活跃”粒子，这改变了 颗粒与宿主细胞膜相互作用。 最简单的模型提出 PVR相互作用后，只有RNA基因组被直接运输 通过病毒特异性离子渗透通道穿过质膜。 第二种模型涉及“传递活性”病毒的传播 颗粒穿过膜进入细胞质并随后释放 来自颗粒的RNA。 为了剖析这些早期事件，建议 研究将建立在博士的基础上。 Chow 和 Tosteson 最近的观察发现 感受态病毒在模型膜中产生离子渗透通道。 在 第一个目标，申请人提出表征电导、动力学 通道的特性和流明尺寸。 他们还将分别 确定对接病毒颗粒对通道形成的影响 使用 PVR 与使用带有抗体包被颗粒的 Fc 受体进行对比。 他们还将监测粒子通道形成中引起的影响 结合 Win 药物或肽特异性抗体的特性。 这 第二个目标将表征参与膜的衣壳蛋白结构域 相互作用并定义它们在病毒进入中的作用。 现有的和新建的 在 VP4 或 VP1 N 末端构建的突变体进入缺陷 将使用模型膜检查通道的任何变化 特性;如果发现，这些将与生物表型相关。 预计该研究将提供生化和 通道结构的生物物理组成，并允许申请人 建立无包膜感染早期阶段的一般模型 病毒。