Quantitative Pcr Analysis Of Mdv In Different Varieties Of Chicken Breeding And Nlrx1, Ips - 1 Gene Expression Differences

Marek’s disease is regarded as an acute, infectious and neoplastic disease, which prefers to infect chickens. Until now, there was no proper cure means for this disease. For further purpose, constructing genus group resisted to MDV could be enormously profit to the poultry industry. MDV include three different serotypes. Meq gene is broadly onsidered as the highly conserved oncogenicity sequence in MDV-I, which leads to the clinical MD in the chicken. In order to study the replicationof MDV in different breeds, we measured the copy number of the MDV in the broiler, layer and Er-Lang mountainous chicken upon infection with MDV by using absolute quantitation method.NLRX1gene, which is likely IPS-1located in mitochondrion, functions as the negative regulatory factor of the IPS-1antivirus signal pathway via interacting with IPS-1signal protein to modify antivirus signal mediated by IPS-1. Meanwhile, it have been reported that the expression of NLRX1gene was up-regulated after virus infection to weaken cytokine response in vivo.The result indicated that different species chicken showed different mortality. According to the statistics result, the mortality of broiler was higher than other two species. Among them, the mortality of cock layer reached peak during latent phase. In the section of analyzing the expression level of meq gene by absolute quantitation, the result showed that the highest level was layer, and then broiler and Er-Lang mountain chicken placed last. This result indicated that Er-Lang mountainous chicken have a capability of controlling replication of virus. Based on the first-four day’s data, there was no apparent difference between the two genders. After7and21DPI (Days post-infection), the expression level of meq gene from broiler cock was higher than hen s, which was the same to the expression level of IPS-1.By contrast, there was no difference between the two genders in layer and Er-lang mountainous chicken. When the layer and broiler had been infected MDV for4days and7days, the expression level of NLRX1gene stabled at the previous level while there was a marked increase of the expression level of NLRX1and IPS-1gene could be detected from several different tissues of Er-Lang mountain chicken. At21d.p.i, the broiler had been incubated MDV for21days, the expression level of IPS-1drive up. At the same time, there was no fluctuation of the expression level of NLRX1gene could be detected. Notably, during this period, the death number of broiler peaked up. Therefore, we speculate there are two possible reasons for leading death at this phase. Firstly, due to the current of MDV-mediated second cytolytic infection in genetically susceptible chickens during latent phase, this process might present in broilers and results in the death of broilers. Secondly, the expression level of IPS-1always maintain at a high level for antiviral immunity, however the expression of NLRX1has not been up-regulated, it cause the overzealous inflammation and ultimately result in the death of broiler.