Packaging of the Segmented Genome of Bacteriophage Phi6

噬菌体 Phi6 分段基因组的包装

• 批准号: 7254096
• 负责人: LEONARD E MINDICH
• 金额: $ 42.68万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-01-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7254096
• 关键词: Animals; Bacteriophages; Binding; Binding Sites; Complex; Condition; Cryoelectron Microscopy; Crystallization; Cystoviridae; Disease; Double Stranded RNA Virus; Double-Stranded RNA; Elements; Epitopes; Family; Family member; Future; Genetic; Genome; Genomic Segment; Genomics; Goals; Human; In Vitro; Integration Host Factors; Investigation; Libraries; Link; Location; Maps; Modeling; Molecular Conformation; Molecular Structure; Motor; Numbers; Peptide Sequence Determination; Peptides; Phage Display; Plants; Protein Region; Proteins; RNA; RNA Binding; Reagent; Reoviridae; Series; Site; Specificity; Staging; Structural Protein; Structure; Surface; System; Transcript; Viral; Viral Genes; Work; comparative; crosslink; image reconstruction; in vivo; member; nucleoside triphosphatase; programs; research study

DESCRIPTION (provided by applicant): Bacteriophages of the family cystoviridae are unique in that they have genomes of 3 segments of double-stranded RNA packaged precisely within a preformed procapsid. Phi6 is the first member of this family and has been studied extensively. A model has been proposed for the mechanism of precise genomic packaging in phi6. The model is strongly supported by the confirmation of predicted results in both in vitro and in vivo packaging. The packaging involves the serially dependent transport of plus strands s, m and I into preformed procapsids with specificity determined by changes in the binding sites on the outside of P1, the major structural protein of the procapsid. The goal of this project is to determine the interaction of the RNA molecules with specific parts of protein P1; to identify the specific elements involved in the changing of the RNA binding sites as the packaging program procedes. This proposal is for the investigation of the location of the binding sites, their amino acid sequences and the determination of the interaction between the RNA and the binding sites. A major question posed is whether the binding sites for the different RNA molecules are physically separate from each other or whether they are overlapping and involve the same regions of protein P1. Approaches utilized in this project include the cross-linking of specific RNA molecules to their binding sites and the use of phage display libraries to locate binding sites. Collaborative structural studies are also proposed in which cores that have packaged different amounts of RNA will be examined by cryoelectron microscopy to determine their changes in conformation. This study also includes a comparative investigation of genomic packaging in the distantly related bacteriophage phi8, which seems to follow the general rules determined for phi6 but with less stringency and with a number of additional features, particularly the participation of host factors and viral genes not found in other members of the cystoviridae. The cystoviridae are the only segmented dsRNA viruses whose mode of packaging is understood. There is no current understanding of the genomic packaging of the reoviridae, segmented dsRNA viruses that cause disease in plants and animals, including humans.

描述（由申请人提供）：胞囊病毒科噬菌体的独特之处在于它们具有精确包装在预制衣壳内的 3 个双链 RNA 片段的基因组。 Phi6 是该家族的第一个成员，并已被广泛研究。已经提出了 phi6 中精确基因组包装机制的模型。该模型得到了体外和体内包装预测结果的确认的有力支持。包装涉及将正链 s、m 和 I 连续依赖地转运至预先形成的衣壳中，其特异性由衣壳主要结构蛋白 P1 外部结合位点的变化决定。该项目的目标是确定 RNA 分子与蛋白质 P1 特定部分的相互作用；识别随着包装程序的进行而改变 RNA 结合位点的特定元素。该提案旨在研究结合位点的位置、氨基酸序列以及确定 RNA 与结合位点之间的相互作用。提出的一个主要问题是不同 RNA 分子的结合位点是否在物理上彼此分离，或者它们是否重叠并涉及蛋白质 P1 的相同区域。该项目使用的方法包括将特定 RNA 分子与其结合位点交联，以及使用噬菌体展示文库来定位结合位点。还提出了协作结构研究，其中包装了不同数量 RNA 的核心将通过冷冻电子显微镜进行检查，以确定它们的构象变化。这项研究还包括对远亲噬菌体 phi8 中基因组包装的比较研究，该噬菌体似乎遵循为 phi6 确定的一般规则，但严格性较低，并且具有许多附加特征，特别是未发现的宿主因子和病毒基因的参与囊病毒科的其他成员。囊病毒科是唯一已知其包装模式的分段双链RNA病毒。目前对呼肠孤病毒科的基因组包装尚无了解，呼肠孤病毒科是一种分段双链RNA病毒，可引起植物和动物（包括人类）疾病。