Pathogenesis of Mumps Virus

描述(申请人提供)：腮腺炎病毒会引起人类的急性感染，约10%的感染会导致无菌性脑膜炎。虽然已知几种腮腺炎病毒基因组序列，但腮腺炎病毒致病的分子基础尚不清楚。这一建议的长期目标是了解病毒如何克服宿主防御机制，特别是病毒蛋白如何在组织培养细胞和动物中在分子水平上战胜宿主先天免疫。猴病毒5(SV5)是一种与腮腺炎病毒关系密切的病毒，其小分子疏水蛋白(SH)在抑制肿瘤坏死因子(TNF)-α激活的细胞凋亡途径中起重要作用，而SH的缺失可导致体内病毒的减毒。假设病毒感染细胞的凋亡抑制参与了病毒的致病过程，而腮腺炎病毒小分子疏水蛋白(SH)在抑制病毒感染细胞(如SV5的SH)的细胞死亡中起重要作用，尽管这两个SH蛋白没有序列同源性。为了验证这些假设，(1)建立了从临床分离株的cDNA中获得传染性腮腺炎病毒的反向遗传学系统，(2)产生了缺乏SH基因的腮腺炎病毒(RMuVdeltaSH)，以及(3)在组织培养细胞和大鼠模型系统中与其亲本腮腺炎病毒进行了比较。自从我于2001年加入宾夕法尼亚州立大学担任终身制病毒学助理教授以来，我们已经确定了在缺乏SH(RSV5deltaSH)的SV5或缺乏V(RSVdeltaC)感染细胞保守C末端的SV5中导致细胞凋亡的途径。我希望建立一个研究项目，了解腮腺炎病毒的致病性与单个腮腺炎病毒蛋白功能之间的关系。本申请中提出的工作建立在我们目前对副粘病毒SV5 SH功能的研究基础上，将我们目前的工作从SV5 SH扩展到腮腺炎病毒SH，并将我们的重点转向病毒蛋白在组织培养系统中的功能，转向在动物模型系统和组织培养细胞中的功能。

DESCRIPTION (provided by applicant): Mumps virus causes acute infections in humans and about 10% of infection leads to aseptic meningitis. Although several mumps virus genome sequences are known, molecular bases of mumps virus pathogenesis are not clear. Long-term goal of this proposal is to understand how virus overcomes host defense mechanisms, especially how viral proteins overcome host innate immunity at molecular levels in tissue culture cells as well as in animals. The small hydrophobic protein (SH) of simian virus 5 (SV5), a virus closely related to mumps virus, plays an important role in inhibiting tumor necrosis factor (TNF)-alpha activated apoptotic pathway and the deletion of SH results in an attenuated virus in vivo. It is hypothesized that inhibition of apoptosis by virus-infected cells contributes to viral pathogenesis and mumps virus small hydrophobic protein (SH) plays essential roles in inhibition of cell death in virus-infected cells like SH of SV5 even though both SH proteins have no sequence homologies. To test these hypothesis, (1) a reverse genetics system in which infectious mumps virus from cDNA of a clinical isolate will be obtained will be established, (2) mumps virus lacking SH gene (rMuVdeltaSH) will be generated and (3) compared with its parental mumps virus in tissue culture cells and in a rat model system. Since my joining Penn State University in 2001 as a tenure-track assistant professor of virology, we have identified pathways leading to apoptosis in SV5 lacking SH (rSV5deltaSH) or in SV5 lacking the conserved C-terminus of V (rSVSVdeltaC)- infected cells. I hope to establish a research program in understanding the relationship between pathogenicity of mumps virus and functions of individual mumps virus proteins. The proposed work in this application builds on our current work on paramyxovirus SV5 SH function, expands our current work from SV5 SH to mumps virus SH and redirects our focus on functions of viral proteins in tissue culture system to that in an animal model system as well as in tissue culture cells.