副粘病毒是人和动物重要致病病毒。病毒包膜与宿主细胞膜融合是其复制和致病的关键步骤，此过程由血凝素-神经氨酸酶（HN）与受体结合后，激活同源融合蛋白（F）完成。HN头颈部是其主要功能区域，也是与F相互作用的区域。一般认为HN的头部与受体结合后将激活信号传递至颈部，再把信号传递至F以激活F，介导膜融合。对头部和颈部保守氨基酸定点突变研究发现，头颈区域内保守氨基酸对HN的功能至关重要，但尚无关于头部和颈部之间相互作用区和连接区功能的报道。为弄清头、颈部之间相互作用区和连接区在HN蛋白促细胞膜融合机制中发挥的作用，本课题拟通过以人副流感病毒（hPIV）和新城疫病毒（NDV）HN蛋白为模型，通过相互作用区和连接区的缺失、突变、替代对HN这两个区域进行研究，阐明HN促细胞融合机制，为副粘病毒感染防控提供理论基础。

Paramyxoviruses are important pathogens for human beings and animals. Paramyxoviruses enter host cells by means of the fusion of the viral and cellular membranes. For most paramyxoviruses, two important surface glycoproteins, the hemagglutinin-neuraminidase (HN) and fusion protein (F), play a crucial role during the fusion process. The fusion protein alone cannot mediate fusion and it requires coexpression of the homologous HN protein. HN consists of four parts: cytoplasmic tail, transmembrane domain, stalk and head. Both head and stalk not only play an important role in HN protein of paramyxovirus,but also confer F protein specificity and mediate the HN-F interaction. Attachment of HN protein to receptors stimulates the transmission of a signal from the globular domain to the F-specific region in the stalk, an interaction of HN protein with F protein, and F protein-mediated membrane fusion. It has also been found that conserved amino acids in head and stalk play an important part in HN protein-mediated cell fusion promotion activity by sited-directed mutagenesis method. However, it has not been reported whether the regional interaction and linkage impact on HN protein-mediated cell fusion promotion or not. To explore the role of the regional interaction and linkage in HN protein-mediating cell fusion promotion, we are going to study the function of the regional interaction and linkage of HN protein by deleting, mutating and substituting amino acids in the regional interaction and linkage.These studies will provide a new strategy for studying prevention and control against paramyxoviruses.