CAREER: Murine Gammaherpesvirus 68 Persistence and Interaction With Host Chemokine Networks

职业生涯奖：小鼠伽马疱疹病毒68与宿主趋化因子网络的持久性和相互作用。病毒及其宿主的进化相互作用反映了不同的适应策略。疱疹病毒是一种共同进化策略，在该策略中，宿主的固有和获得性免疫防御和细胞信号通过病毒诱导的调节来平衡，这些调节通常会导致改变的动态平衡，促进病毒和多细胞宿主的永久联系。在保持这种平衡的同时，通常不会对东道主的健康造成什么影响。疱疹病毒的大DNA基因组编码大量的辅助基因，这些辅助基因对病毒复制是不必要的，但通过调节宿主反应而与病毒的持久性密切相关。伽马疱疹病毒能够在淋巴细胞中持续存在，它含有特别令人印象深刻的各种基因，显然是通过分子盗用宿主基因获得的，这些基因与免疫识别和反应、细胞周期控制、补体介导的杀伤和凋亡反应有关。在伽马-2-疱疹病毒(或横纹病毒)的遗传谱系中，突出的是编码与宿主趋化因子网络相互作用的产物的基因，这在体内平衡和炎症条件下的细胞交通调节中都是至关重要的。在几个RhadinVirus基因组中保守的是G蛋白偶联受体(GPCR)基因，编码与CXCR2关系最密切的CXC趋化因子受体同源物。对伽马疱疹病毒潜伏期和持久性的研究以及对由小鼠伽马疱疹病毒68(MHV-68)的ORF74编码的病毒CXC趋化因子受体的功能分析将在这些研究中进行，学生们将广泛参与。利用强大的遗传工具研究MHV-68与小鼠宿主的相互作用是非常容易的，使该系统非常适合于促进对伽马疱疹病毒生物学的了解，包括伽马疱疹病毒潜伏和持续的机制。MHV-68基因组已经完全测序，可以使用传统的体外重组方法进行操作。基因定义的小鼠品系(包括转基因品系和具有特定基因敲除的品系)的可获得性提供了无与伦比的机会，利用病毒和宿主遗传学的操纵来质疑病毒-宿主关联的性质。这些关于MHV-68持久性和与宿主趋化因子网络相互作用的研究将利用该病毒-宿主系统的优势。已知的伽马疱疹病毒-宿主相互作用的耐人寻味的本质，适当的实验方法的优雅，包括那些分子生物学的标准方法，以及大量未回答的问题一起提供了一个研究框架，非常适合于整合到涉及研究生、本科生和预科学生及其教师的教育活动中。使用普通分子生物学方法对MHV-68克隆基因的研究将继续为初级和高级分子生物学实验室课程提供以探究为基础的背景。利用首席研究员在构建重组Rhadino病毒以研究病毒环境中的基因功能方面的丰富经验，研究生项目将包括构建有助于了解病毒与宿主相互作用的MHV-68重组体。研究生和本科生都将使用克隆的病毒基因表达结构在体外进行MHV-68基因功能的研究。与地区性高中生及其老师的持续互动将为被选中的学生提供机会，利用基本的分子生物学方法参与定义明确的小型实验室研究项目。

CAREER Award: Murine gammaherpesvirus 68 persistence and interaction with hostchemokine networks.The evolutionary interactions of viruses and their hosts reflect diverse adaptive strategies.Herpesviruses exemplify a co-evolutionary strategy in which host innate and adaptive immune defenses and cellular signalling are balanced by virus induced modulations that typically result in an altered homeostasis facilitating permanent association of the virus and the multicellular host. While this balance is maintained, there is usually little cost in fitness for the host. The large DNA genomes of herpesviruses encode numerous accessory genes unnecessary for viral replication but critically involved in virus persistence through modulation of host responses. Gammaherpesviruses, which are capable of persistence in lymphoid cells, contain a particularly impressive variety of genes apparently acquired through molecular piracy of host genes relevant to immune recognition and response, cell cycle control, complement-mediated killing, and apoptotic responses. Prominent within the genetic repertoire of gamma-2-herpesviruses (or rhadinoviruses) are genes encoding products that interact with host chemokine networks which are critical in regulation of cell traffic under both homeostatic and inflammatory conditions. Conserved within several rhadinovirus genomes is a G-protein-coupled receptor (GPCR) gene encoding a putative CXC-chemokine receptor homolog most closely related to CXCR2. Studies of gammaherpesvirus latency and persistence together with functional analysis of the viral CXC chemokine receptor encoded by ORF74 of murine gammaherpesvirus 68 (MHV-68) will be pursued in these studies with extensive student participation. Interaction of MHV-68 with murine hosts is highly accessible to investigation usingpowerful genetic tools making this system ideally suited for advancing understanding ofgammaherpesvirus biology including mechanisms of gammaherpesvirus latency and persistence.The MHV-68 genome has been fully sequenced and can be manipulated using conventional in vitro recombination methods. Availability of genetically defined mouse strains (including transgenic strains and those with specific gene knockouts) affords unparalleled opportunities to query the nature of the virus-host association using manipulations of both virus and host genetics. These investigations of MHV-68 persistence and interaction with host chemokine networks will exploit the advantages of this virus-host system. The intriguing nature of known gammaherpesvirus-host interactions, the elegance ofappropriate experimental methods including those that are standard to molecular biology, and the abundance of unanswered questions together provide a research framework that is well suited for integration into educational activities involving graduate students, undergraduates, and pre-college students and their teachers. Studies of cloned MHV-68 genes using common molecular biological methods will continue to provide an inquiry-based context for introductory and advanced molecular biology laboratory courses. Drawing upon the extensive experience of the principal investigator in construction of recombinant rhadinoviruses for study of gene function within the viral context, graduate student projects will include construction of MHV-68 recombinants useful for understanding virus-host interactions. Both graduate and undergraduate students will perform studies of MHV-68 gene function in vitro using cloned viral gene expression constructs. Ongoing interactions with regional high school students and their teacherswill provide opportunities for selected students to participate in small, well defined laboratory research projects utilizing basic molecular biological methods.