Effects Of NDRG1 Protein On Replication Of Avian Influenza A/H5N1 Virus In Cells

Influenza is a common respiratory tract infections with highly contagious disease.It is caused by influenza A virus,a member of the family Orthomyxoviridae.Influenza A virus belongs to cellular parasite,and must rely on cellular factors and synthesis mechanism to complete its replication cycle.Meanwhile,host immune response was caused by IAVs infection and a lot of antiviral factors were induced and defensed virus infection.Thus,it is an important and significant thing to study the interaction of influenza A virus and host factors.It can help us know how host defenses IAVs infection,as well as how virus escapes from host immune response and fulfill itself replication.It also help us develop new antiviral target sites.NDRG1 is a cytoplasmic protein and highly expresses in epithelial cell.It is a multifunctional protein,and regulate many cell signaling pathway.It plays an important role in mast cell maturation,differentiation,cell cycle regulation,angiogenesis,metastasis suppression and p53-mediated apoptosis.It can also attenuate NF-κB signal pathway,reducing the expression of relevant cellular factors.It imples that NDRG1 has a connection with host innate immune response.Hereby,the effects of NDRG1 for the replication of avian influenza A/H5N1 virus in A549 cell were studied.First,the results of RT-qPCR and Western Blot showed that the level of NDRG1 were upregulated by virus infection.Sond,RNAi vector targeting NDRG1 was generated by pLKO.1 TRC cloning vector and overexpression vector was constructed by pEGFP-C1 plasmid.The effects for virus were studied by knockdown and overerpression NDRG1.A consistent results were found that NDRG1 could facilitate the replication of avian influenza A/H5N1 virus.Third,IKKβ expression vector was constructed and evaluated whether it could overcome the inhibitor of NDRG1 for NF-κB signal pathway by the expression level of IFN-β、IL-8 and the replication capacity of virus.The studies revealed that IKKβ expression vector overcame the inhibitor effects of NDRG1,and the replication of virus was also declined.So it was certified that NDRG1 could facilitate avian influenza A/H5N1 virus replication by attenuating canonical NF-κB signal pathway,reducing the innate immune response of host cell for influenza infection.