MEMBRANE BOUND RNA VIRUS REPLICATION COMPLEXES

这个子项目是许多利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 电子显微镜层析成像（EMT）的三维性质克服了二维EM分析的许多严重限制，揭示了许多传统透射EM分析无法获得的基本特征。我们采用EMT和先进的模式病毒，鸡舍病毒（FHV）和雀麦花叶病毒（BMV），了解组织的膜结合，囊泡样RNA复制复合物（小球）诱导的许多重要的正链RNA病毒。正链RNA病毒是最大的病毒遗传类别，包括许多严重的人类病原体。正链RNA病毒的RNA复制普遍与膜和膜重排如单或双膜囊泡有关。然而，在大多数情况下，RNA合成的网站（S）相对于这些重排的膜和膜之间的拓扑关系，囊泡内部，内腔室，和细胞质的定义很差。最近的结果表明，至少在某些情况下，病毒RNA复制发生在这样的囊泡内。然而，这些发现留下了许多未解决的问题，在许多方面，由于固有的二维分析的局限性。野田村病毒家族中研究最多的成员FHV在受感染的果蝇细胞的线粒体外膜上复制，在膜间隙形成膜结合小球，类似于许多正链RNA病毒观察到的多囊泡结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The three-dimensional nature of electron microscope tomography (EMT) overcomes many serious limitations of two-dimensional EM analysis to reveal many fundamental features not accessible from conventional transmission EM analyses. We employ EMT and the advanced model viruses, flock house virus (FHV) and brome mosaic virus (BMV), to understand the organization of the membrane-bounded, vesicle-like RNA replication complexes (spherules) induced by many important positive-strand RNA viruses. Positive-strand RNA viruses are the largest genetic class of viruses and include many serious human pathogens. RNA replication by positive-strand RNA viruses is universally associated with membranes and membrane rearrangements such as single or double membrane vesicles. However, in most cases the site(s) of RNA synthesis relative to these rearranged membranes and the topological relationships among membranes, vesicle interiors, lumenal compartments, and the cytoplasm are poorly defined. Recent results suggest that, in at least some cases, viral RNA replication occurs inside such vesicles. However, these findings leave many unresolved questions, in many ways due to limitations inherent to the two-dimensional analyses used. The best-studied member of the nodavirus family, FHV, replicates at the outer mitochondrial membranes of infected Drosophila cells where membrane-bound spherules form in the intermembrane space, similar to multi-vesicular structures observed for many positive-strand RNA viruses.