Identification and characterization of viral and cellular factors that protect from Bornavirus-induced neuronal degeneration in the hippocampus

关于防止病毒诱导的中枢神经系统神经元变性的宿主细胞因子和细胞信号通路知之甚少。利用不同品系大鼠的海马切片培养，我们最近发现博尔纳病病毒（BDV）诱导的齿状回颗粒细胞神经元变性依赖于大鼠的遗传背景，并被可溶性宿主因子所阻止。我们现在的目标是通过生物化学方法鉴定保护因子，包括富集和随后的基于质谱的分析鉴定。功能实验将被应用于表征这些因子保护神经元细胞死亡的效力。我们还可以通过全基因组关联研究（GWAS）在Sprague-Dawley大鼠中发现一个携带多个候选基因的耐药位点。为了深入了解触发神经元存活的细胞信号事件，我们希望使用新开发的编码功能性miRNA的BDV载体，通过敲低和过表达方法研究GWAS鉴定的细胞候选基因的参与。最后，我们想挑战我们的假设，即病毒X蛋白通过干扰细胞凋亡途径促进慢性感染，从而有助于感染海马培养物中神经元的存活。通过这些研究，我们希望能够阐明病毒诱导的神经元变性中涉及的研究不足的宿主反应途径。

Little is known about host cell factors and cellular signaling pathways that prevent from virus-induced neuronal degeneration in the central nervous system. Using hippocampal slice cultures of various rat strains we could recently show that the Borna disease virus (BDV) induced degeneration of granule cell neurons of the dentate gyrus is dependent on the rat genetic background and prevented by soluble host factors. Our goal is now to identify the protective factors by biochemical methods, including enrichment and subsequent identification by mass spectrometry-based analysis. Functional experiments will be applied to characterize the potency of these factors to protect from neuronal cell death. We also could identify by genome-wide association studies (GWAS) one resistance locus in Sprague-Dawley rats harboring several candidate genes. To gain insight into the cellular signaling events that triggers neuronal survival, we want to investigate the involvement of the cellular candidate genes identified by GWAS by knock-down and overexpression approaches using newly developed BDV vectors encoding functional miRNAs. Finally, we want to challenge our hypothesis that the viral X protein contributes to neuronal survival in infected hippocampal cultures by interfering with cellular apoptosis pathways to promote chronic infection. With these studies we hope to shed light onto the poorly investigated host response pathways that are involved in virus-induced neuronal degeneration.