Hantavirus RNA Encapsidation and Packaging

描述(申请人提供)：这是一份全面研究汉坦病毒核衣壳蛋白(N)在病毒复制中作用的修订申请。汉坦病毒包括A类病原体，是布尼亚病毒科的成员，包括A类和C类病原体。在汉坦病毒感染期间发生的RNA包装原理很可能适用于汉坦病毒属的其他成员，整个布尼亚病毒科，以及其他具有重要医学意义的节段式负链RNA病毒，如流感。所有负链、节段化的RNA病毒都有基因组片段，通过基因组末端的相互作用形成“狭长柄”。我们发现，这种病毒RNA(VRNA)狭柄是汉坦病毒N的主要高亲和力结合底物。我们将进行补充的体外和体内实验，以表征正确将病毒RNA包装成颗粒所需的决定因素。我们还发现，汉坦病毒N蛋白是一种强大的RNA伴侣蛋白，它能瞬间解离高阶RNA结构，促进具有生物功能的高阶结构的形成。因此，我们将进行实验，以表征N相关RNA伴侣功能在病毒复制中的作用。特别是，我们将描述N在狭长柄形成和病毒RNA复制启动中的作用。我们还发现，在翻译起始过程中，N模仿帽结合复合体的多个细胞肽的活性。我们将进一步描述N在这一过程中的作用。虽然N在复制过程中有多个步骤发挥作用，但我们认为N的共同内在活动介导了这些生物学功能。除了描述汉坦病毒N的生物学特征外，我们还将利用我们观察到的N与vRNA狭长柄之间的高亲和力相互作用来识别抑制N功能和病毒复制的分子。与公共卫生相关：汉坦病毒导致汉坦病毒肺综合征，该综合征在人类中具有很高的死亡率。与汉坦病毒密切相关的其他病毒会引起包括出血热在内的多种人类疾病。我们拟议工作的目标是确定对病毒复制至关重要的一种病毒蛋白的显著生物学功能，并确定有效阻止这些病毒复制的药物。

DESCRIPTION (provided by applicant): This is a revised application to comprehensively examine the roles of hantavirus nucleocapsid protein (N) in virus replication. Hantaviruses include Category A pathogens and are members of the Bunyaviridae family which includes both Category A and C pathogens. It is likely that the principles of RNA packing that take place during hantavirus infection will be applicable to the other members of the hantavirus genus the entire Bunyaviridae family, and other medically important segmented minus strand RNA viruses such as influenza. All minus strand, segmented RNA viruses have genome segments that are found in "panhandle" formation via interaction of the genome termini. We have found that this viral RNA (vRNA) panhandle is the primary high affinity binding substrate for hantavirus N. We will carry out complementary in vitro and in vivo experiments to characterize the determinants required for correct packaging of viral RNA into particles. We have also found that hantavirus N protein is a robust RNA chaperone that transiently dissociates higher order RNA structure to facilitate formation of higher order structures with biological function. Thus, we will carry out experiments to characterize the role of N- associated RNA chaperone function in virus replication. In particular we will characterize the role of N in panhandle formation and in the initiation of viral RNA replication. We have also found that N mimics the activity of multiple cellular peptides of the cap-binding complex during translation initiation. We will further characterize the role of N in this process. Although N functions in multiple steps in replication, we think that common intrinsic activities of N mediate these biological functions. In addition to characterizing the features of the biology of hantavirus N, we will use our observed high affinity interaction between N and the vRNA panhandle to identify molecules that inhibit N function and virus replication. PUBLIC HEALTH RELEVANCE: Hantaviruses cause hantavirus pulmonary syndrome which has a high mortality rate in humans. Other viruses closely related to hantaviruses cause a diverse set of human diseases including hemorrhagic fever. The goal of our proposed work is to identify salient biological functions of one of the viral proteins crucial to virus replication and to identify drugs effective in blocking the replication of these viruses.