Correlation of Sendai Virus Mutations with Pathogenicity

仙台病毒突变与致病性的相关性

• 批准号: 8274628
• 负责人: NANCY Lugene MCQUEEN
• 金额: $ 10.73万
• 依托单位: CALIFORNIA STATE UNIVERSITY LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-17 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8274628
• 关键词: Address; Affect; Amino Acids; Animals; Antiviral Agents; Avian Influenza A Virus; Bacterial Infections; Behavior; Biological Assay; Cells; Cellular biology; Communities; Development; Disease; Equipment; Exhibits; Funding; Genes; Genetic; Genetic Transcription; Genome; Genomics; Glycine decarboxylase; Goals; Human; Infection; Investigation; Journals; Knowledge; Lead; Medical; Messenger RNA; Microtubules; Modeling; Molecular; Mus; Mutation; Nature; Nipah Virus; Outcome; Paramyxovirus; Pathogenicity; Phenotype; Phosphoproteins; Play; Production; Proteins; Publishing; RNA; RNA chemical synthesis; Reagent; Research; Research Design; Research Methodology; Resources; Respiratory System; Respiratory Tract Infections; Respiratory tract structure; Reverse Transcriptase Polymerase Chain Reaction; Role; SARS coronavirus; Sendai virus; Site; Structure; Students; Study Section; Systemic infection; Talents; Techniques; Technology; Testing; Time; Toxic effect; Translations; Tropism; Trypsin; Underrepresented Minority; Variant; Viral; Viral Genes; Viral Pathogenesis; Viral Proteins; Viral Respiratory Tract Infection; Virion; Virulence; Virulent; Virus; Virus Assembly; Virus Diseases; Work; Y protein; base; effective therapy; experience; glycosylation; innovation; insight; man; meetings; multiple myeloma M Protein; novel therapeutic intervention; parainfluenza virus; pathogen; positional cloning; protein function; public health relevance; recombinant virus; response; tissue culture; tissue/cell culture; viral RNA; virus host interaction

DESCRIPTION (provided by applicant): With the emergence of new human viral pathogens such as the SARS virus, Nipah virus, and the avian influenza viruses, the importance of investigations on the genetic basis of viral infections becomes clear. A major goal of this lab is to study the structure and function of Sendai virus proteins as they relate to viral pathogenicity. Sendai virus is a murine parainfluenza virus similar in structure to other paramyxoviruses that continue to be a major cause of human infection in modern man. Knowledge gained from studying Sendai virus may be applied to paramyxoviruses and other similar viruses that infect man and may lead to new therapeutic interventions. Wild-type (wt) Sendai virus causes a pneumotropic infection in mice. F1-R, a pantropic variant, causes a systemic infection. We previously hypothesized that the pantropism of F1-R is due to two phenotypic differences of the virus as compared to wt virus. One difference is the enhanced proteolytic cleavability of the fusion (F) protein of F1-R which we attributed to amino acid changes in F. Another difference is the microtubule disruption and subsequent viral bipolar budding in F1-R infections which we attributed to two amino acid differences in the matrix (M) protein of the virus. To prove our hypothesis we used reverse genetics to create recombinant viruses containing various combinations of theF1-R F and M mutations. The only virus that was able to form plaques and undergo multiple rounds of replication in LLC-MK2 cells in the absence of trypsin, or cause a systemic infection in mice was RRGV0, a virus containing all F1-R M and F changes. From these studies we could conclude that changes in the F and M genes of F1-R are sufficient to allow the virus to cause a systemic infection. The first specific aim is to determine what combination of mutations in F and M are required for the virus to form plaques and/or to undergo multiple rounds of replication in LLC-MK2 cells in the absence of trypsin and to correlate these phenotypes with virulence in mice. In tissue culture infections F1-R produces fewer viruses than wt virus or RGV0. RGV0 appeared to be more pathogenic to the mice than F1-R. We hypothesize that it is due to a higher rate of virus production in the infection caused by RGV0 as compared to the F1-R infection and that this is due to changes in the P and/or L genes of F1-R. The second specific aim of this project is to create variants of Sendai virus with all F1-R F and M mutations combined with F1-R mutations in the P and/or L genes. The purpose is to identify mutations in the F1-R that contribute to the decreased virus production and decreased pathogenicity of the virus. The third specific aim of this project is to determine if the decreased production of virus in F1-R infections is due to decreased replication/transcription rates, decreases in viral assembly and budding, or decreased inhibition of the host innate responses. PUBLIC HEALTH RELEVANCE: With the emergence of new viral human pathogens from variants of viruses that infect other animals, such as the Nipah and SARS viruses and the avian influenza virus, the importance of investigations on the genetic basis of viral infections becomes clear. The studies described in detail in this proposal provide a platform to study how changes in the genes of Sendai virus, which causes a respiratory tract infection in mice, contribute to viral pathogenesis (ability to cause disease) in tissue culture cells and in mice. Studies on the molecular mechanisms of Sendai virus infections in mice are significant in that they may provide important insights on how to more effectively control similar infections in man.

描述（由申请人提供）：随着新的人类病毒病原体的出现，例如SARS病毒，Nipah病毒和鸟类流感病毒，对病毒感染的遗传基础进行研究的重要性变得很明显。该实验室的主要目标是研究与病毒致病性有关的仙台病毒蛋白的结构和功能。仙台病毒是一种与其他帕托氏菌病毒相似的鼠parainfluenza病毒，这些病毒的结构相似，这些病毒仍然是现代人类感染的主要原因。从研究仙台病毒中获得的知识可能应用于感染人并可能导致新的治疗干预措施的其他类似病毒。野生型（WT）仙台病毒在小鼠中引起肺炎感染。 F1-R是一种泛质变体，会引起全身感染。我们先前假设，与WT病毒相比，F1-R的泛型是由于该病毒的两个表型差异所致。一个差异是F1-R融合蛋白（F）蛋白的蛋白水解溶性增强，我们归因于F中的氨基酸变化。另一个差异是微管的破坏和随后的F1-R感染中的病毒双极出芽，我们将其归因于病毒素的基质（M）蛋白质中的两个氨基酸差异。为了证明我们的假设，我们使用反向遗传学创建了包含F1-R F和M突变各种组合的重组病毒。在没有胰蛋白酶的情况下，唯一能够在LLC-MK2细胞中形成斑块并在LLC-MK2细胞中进行多个复制的病毒是RRGV0，这是一种含有所有F1-R M和F变化的病毒。从这些研究中，我们可以得出结论，F1-R的F和M基因的变化足以使病毒引起全身感染。第一个具体目的是确定病毒在没有胰蛋白酶的情况下形成斑块和/或在LLC-MK2细胞中形成斑块和/或经历多发复制需要的突变组合，并将这些表型与小鼠中的病毒率相关联。在组织培养物感染中，F1-R产生的病毒少于WT病毒或RGV0。 RGV0似乎对小鼠比F1-R更具致病性。我们假设这是由于与F1-R感染相比，由RGV0引起的感染中的病毒产生率更高，这是由于F1-R的P和/或L基因的变化所致。该项目的第二个特定目的是创建所有F1-R F和M突变与P和/或L基因中的F1-R突变结合的变体。目的是鉴定F1-R中的突变导致病毒产生降低和病毒致病性降低。该项目的第三个具体目的是确定F1-R感染中病毒产生的降低是由于复制/转录率降低，病毒组装和发芽的降低，或者对宿主先天反应的抑制减少。 公共卫生相关性：随着感染其他动物（例如Nipah和Sars病毒和禽流感病毒）的病毒变异的新病毒人病原体的出现，对病毒感染的遗传基础进行研究的重要性变得很明显。该提案中详细描述的研究提供了一个平台，可以研究如何在小鼠中引起呼吸道感染的仙台病毒基因的变化，从而有助于病毒发病机理（能够引起疾病）在组织培养细胞和小鼠中。关于小鼠仙台病毒感染的分子机制的研究很重要，因为它们可能会提供有关如何更有效地控制人类中类似感染的重要见解。