title: Cell attachment protein VP8* of a human rotavirus specifically interacts with A-type histo-blood group antigen.
abstract: As with many other viruses, the initial cell attachment of rotaviruses, which are the major causative agent of infantile gastroenteritis, is mediated by interactions with specific cellular glycans. The distally located VP8* domain of the rotavirus spike protein VP4 (ref. 5) mediates such interactions. The existing paradigm is that 'sialidase-sensitive' animal rotavirus strains bind to glycans with terminal sialic acid (Sia), whereas 'sialidase-insensitive' human rotavirus strains bind to glycans with internal Sia such as GM1 (ref. 3). Although the involvement of Sia in the animal strains is firmly supported by crystallographic studies, it is not yet known how VP8* of human rotaviruses interacts with Sia and whether their cell attachment necessarily involves sialoglycans. Here we show that VP8* of a human rotavirus strain specifically recognizes A-type histo-blood group antigen (HBGA) using a glycan array screen comprised of 511 glycans, and that virus infectivity in HT-29 cells is abrogated by anti-A-type antibodies as well as significantly enhanced in Chinese hamster ovary cells genetically modified to express the A-type HBGA, providing a novel paradigm for initial cell attachment of human rotavirus. HBGAs are genetically determined glycoconjugates present in mucosal secretions, epithelia and on red blood cells, and are recognized as susceptibility and cell attachment factors for gastric pathogens like Helicobacter pylori and noroviruses. Our crystallographic studies show that the A-type HBGA binds to the human rotavirus VP8* at the same location as the Sia in the VP8* of animal rotavirus, and suggest how subtle changes within the same structural framework allow for such receptor switching. These results raise the possibility that host susceptibility to specific human rotavirus strains and pathogenesis are influenced by genetically controlled expression of different HBGAs among the world's population.
authors.affiliation: Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Liya
authors.initials: L
authors.lastname: Hu
authors.forename: Sue E
authors.initials: SE
authors.lastname: Crawford
authors.forename: Rita
authors.initials: R
authors.lastname: Czako
authors.forename: Nicolas W
authors.initials: NW
authors.lastname: Cortes-Penfield
authors.forename: David F
authors.initials: DF
authors.lastname: Smith
authors.forename: Jacques
authors.initials: J
authors.lastname: Le Pendu
authors.forename: Mary K
authors.initials: MK
authors.lastname: Estes
authors.forename: B V Venkataram
authors.initials: BV
authors.lastname: Prasad
mesh_terms: D000017:ABO Blood-Group System / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D018360:Crystallography, X-Ray; D004912:Erythrocytes / Q000378:metabolism / Q000821:virology; D058507:Host Specificity / Q000502:physiology*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D011991:Receptors, Virus / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012401:Rotavirus / Q000737:chemistry / Q000145:classification / Q000378:metabolism / Q000472:pathogenicity; D017361:Viral Nonstructural Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000017:ABO Blood-Group System; D016601:RNA-Binding Proteins; D011991:Receptors, Virus; D017361:Viral Nonstructural Proteins; C079234:NS35 protein, rotavirus; D019158:N-Acetylneuraminic Acid