title: Structural basis for receptor specificity of influenza B virus hemagglutinin.
abstract: Receptor-binding specificity of HA, the major surface glycoprotein of influenza virus, primarily determines the host ranges that the virus can infect. Influenza type B virus almost exclusively infects humans and contributes to the annual "flu" sickness. Here we report the structures of influenza B virus HA in complex with human and avian receptor analogs, respectively. These structures provide a structural basis for the different receptor-binding properties of influenza A and B virus HA molecules and for the ability of influenza B virus HA to distinguish human and avian receptors. The structure of influenza B virus HA with avian receptor analog also reveals how mutations in the region of residues 194 to 196, which are frequently observed in egg-adapted and naturally occurring variants, directly affect the receptor binding of the resultant virus strains. Furthermore, these structures of influenza B virus HA are compared with known structures of influenza A virus HAs, which suggests the role of the residue at 222 as a key and likely a universal determinant for the different binding modes of human receptor analogs by different HA molecules.
authors.affiliation: Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA. qinghuaw@bcm.tmc.edu
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Wang
authors.forename: Xia
authors.initials: X
authors.lastname: Tian
authors.forename: Xiaorui
authors.initials: X
authors.lastname: Chen
authors.forename: Jianpeng
authors.initials: J
authors.lastname: Ma
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001717:Birds; D018360:Crystallography, X-Ray; D006388:Hemagglutinins / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D009981:Influenza B virus / Q000737:chemistry*; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000378:metabolism*; D013045:Species Specificity; D013329:Structure-Activity Relationship
chemical_list: D006388:Hemagglutinins; D011956:Receptors, Cell Surface