流感病毒血凝素蛋白（HA）的成熟状态决定了病毒组装及对靶细胞的感染效率。现已知HA的折叠和成熟需要细胞内质网伴侣分子Calnexin (CNX)、Calreticulin(CRT)及Erp57的参与，但这三者通过调节HA蛋白的成熟继而影响病毒对宿主细胞的感染的机理尚不明确。在前期研究中，我们发现CRT的缺失不会影响HA蛋白由内质网至细胞膜的运输，但会影响HA蛋白的功能性成熟。为进一步研究CNX、CRT和Erp57影响HA蛋白终成熟的机制及三者的协作关系，我们构建了CNX、Erp57单基因敲除及CNX/CRT、CNX/Erp57和CRT/Erp57双基因敲除细胞系，拟研究在不同分子缺失及过表达情况下HA蛋白表达的时间和空间规律，以及HA所整合的伪型病毒对细胞的感染水平差异，以期在蛋白和病毒粒子两个层面确定影响HA蛋白成熟的关键因素，从而为新的抗病毒药物研发提供理论基础。

Hemagglutinin (HA) of influenza virus is key determinant in viral attachment, entry, and infection of target cells, maturation of HA is the prerequisite for packaging of infectious virus particles. It has been well established that three molecular chaperones in cellular endoplasmic reticulum, Calnexin (CNX), Calreticulin (CRT) and Erp57, are involved in the maturation of HA. How these molecules, however, influence viral infectivites through promoting HA’s maturation is still unknown. In our previous study, we found that knocking out of CRT did not influence HA trafficking from endoplasmic reticulum to cell membrane, but inhibited functional maturation of HA. To further illustrate the roles of CNX, CRT and Erp57 in HA maturation, we screened CNX and Erp57 single knock out as well as CNX/CRT, CNX/Erp57 and CRT/Erp57 double knock out cell lines. These genetic knock out cells, together with CNX, CRT and Erp57 over-expressing cells, will be used to study the expression profile of HA protein in both time and space manners. In addition, infectivities of HA-pseudotyping viruses from different cell lines will be tested. Results of this study will extend our knowledge about HA maturation, and is valuable for the development of new anti-viral drugs.