Structural basis for the divergent evolution of influenza B virus hemagglutinin.
Influenza A and B viruses are responsible for the severe morbidity and mortality worldwide in annual influenza epidemics. Currently circulating influenza B virus belongs to the B/Victoria or B/Yamagata lineage that was diverged from each other about 30-40 years ago. However, a mechanistic understanding of their divergent evolution is still lacking. Here we report the crystal structures of influenza B/Yamanashi/166/1998 hemagglutinin (HA) belonging to B/Yamagata lineage and its complex with the avian-like receptor analogue. Comparison of these structures with those of undiverged and diverged influenza B virus HAs, in conjunction with sequence analysis, reveals the molecular basis for the divergent evolution of influenza B virus HAs. Furthermore, HAs of diverged influenza B virus strains display much stronger molecular interactions with terminal sialic acid of bound receptors, which may allow for a different tissue tropism for current influenza B viruses, for which further investigation is required.
Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Department of Bioengineering, Rice University, Houston, TX 77005, USA.
Fengyun
F
Ni
Elena
E
Kondrashkina
Qinghua
Q
Wang
D018360:Crystallography, X-Ray; D019143:Evolution, Molecular; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry* / Q000235:genetics; D006801:Humans; D009981:Influenza B virus / Q000737:chemistry* / Q000235:genetics; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D011991:Receptors, Virus / Q000378:metabolism; D012794:Sialic Acids / Q000378:metabolism; D053585:Virus Attachment
D019267:Hemagglutinin Glycoproteins, Influenza Virus; D011991:Receptors, Virus; D012794:Sialic Acids
Divergent evolution; Hemagglutinin; Influenza B virus; Positive selective pressure; Receptor binding; Sialic acid receptors