中文摘要：

传染性法氏囊病（IBD）是由传染性法氏囊病病毒（IBDV）引起的一种高度危害养鸡业的传染病。肿瘤抑制蛋白p53能够抑制多种病毒的复制,但对IBDV复制的影响仍然不清楚。本研究以IBDV为模式病毒,采用体外感染模式,在IBDV感染的DF-1细胞中,p53的表达水平和活性均显著升高。p53过表达可以抑制IBDV的复制,并激活鸡体抗病毒天然免疫基因（IPS-1、IRF3、PKR、OAS、Mx）的表达水平上调;抑制p53的表达则得到相反的结果;表明p53可以激活鸡体的抗病毒天然免疫反应发挥抗IBDV感染作用。利用生物信息学方法和双荧光素酶报告系统分析发现,gga-miR-2127可以作用于p53 mRNA的3＇UTR;荧光定量RT-PCR和免疫印迹分析表明gga-miR-2127可以使p53的蛋白水平表达降低,但mRNA水平没有变化;gga-miR-2127过表达可以使鸡体的抗病毒天然免疫基因表达降低,IBDV复制水平升高。本研究表明：gga-miR-2127可以作用于p53 mRNA的3＇UTR调控p53的表达从而影响其下游抗病毒天然免疫基因的表达来发挥抗IBDV感染的作用。

英文摘要：

Infectious bursal disease （IBD） is a highly risky disease caused by infectious bursal disease virus （IBDV）. Although the tumor suppressor protein, p53, can inhibit the replication of a variety of virus, its effect on IBDV replication remains unknown. In the present study, the p53 was used in vitro to investigate its antiviral effects in chicken by using the IBDV as a model virus. The expression level and activity of p53 were markedly increased in IBDV-infected DF-1 cells. The over-expression of p53 could inhibit IBDV replication and up-regulate the expression level of the antiviral innate immune genes in chicken （IPS-1, IRF3, PK OAS, Mx）, whereas suppression of p53 could lead to the contrary results. Our results showed that p53 could activate the antiviral innate immune response against IBDV infection in chicken. Results of bioinformatics and dual-luciferase reporter system showed that gga-miR-2127 could target the 3’UTR of p53. The results of qRT-PCR and immune blotting showed that the over-expression of gga-miR-2127 could down-regulate the expression level of the antiviral innate immune genes in chicken and promote the replication level of IBDV. Our results suggested that gga-miR-2127 can target the 3’UTR of chicken p53, the antiviral factor that enhances the antiviral innate immune response to IBDV.