马立克氏病毒感鸡胸腺转录组学及其相关新功能基因的发现

Marek's disease virus (MDV) is a cell-associated,oncologic hepersvirus which causes a T lymphocytes proliferation in chickens. However the pathogenesis of the virus is still not very clear.The high throughput of microarray could provide a gene expression profile to differen stimulation. With this new technology we could find new genes during the interreactions between virus and host.In this project we will infect chickens with MDV RB1B and then isolate the RNA from thymus and make it reverse transcript. We will investigate the different gene exprssion and gene regulation during the chicken infected with very virluent MDV by transcripional profile analysis. The results will be confirmed by real time PCR. The function genes will be confirmed by mutant virus. Our results will provide new theory in MDV control and also will be very important in comparative Medicine

马立克氏病毒(MDV)是一种细胞结合型肿瘤性疱疹病毒，引起鸡的T淋巴增生性疾病，有关致病机制仍不清楚。基因芯片的高通量能够呈现不同刺激的基因表达谱，获得病毒和宿主差异变化的基因。本项目通过感染MDV鸡胸腺，提取RNA并反转录，利用基因芯片技术研究病毒和宿主基因水平的调控机制，并用荧光定量PCR和病毒基因缺失等技术方法验证，发现新的功能基因，提出病毒与宿主相互作用，肿瘤发生发展的网络机制，为MDV 控制提出新的理论基础，研究结果对比较医学也具有重要意义。

通过转录组学、生物信息学和microRNA等研究方法，探索了MDV超强毒RB1B株感染鸡胸腺组织后不同致病阶段基因变化。研究发现，在鸡胸腺组织中，病毒潜伏感染期建立时间为感染后14天，参与免疫、细胞周期与凋亡途径的基因转录水平下调，而与肿瘤相关的信号途径上调。CD4和CD8分子表达与TLR3信号呈正相关，均显著下调，揭示了MDV可能通过TLR3信号影响了MDV特异性T细胞免疫应答。研究发现调控TLR3信号可以显著影响RB1B病毒的感染和复制。TLR3 是mdv1-miR-M4-5p和gga-miR-155的靶基因，后者可以直接与TLR3编码区第 967-973位核苷酸结合。这是在禽类物种中第一次发现microRNA通过作用于基因编码区发挥作用，特别是首次证实病毒编码的microRNA可以直接作用于宿主基因编码区发挥调控功能，这极大地丰富了microRNA调控理论。