title: Heparan sulfate is a selective attachment factor for the avian coronavirus infectious bronchitis virus Beaudette.
abstract: The avian coronavirus infectious bronchitis virus (IBV) strain Beaudette is an embryo-adapted virus that has extended species tropism in cell culture. In order to understand the acquired tropism of the Beaudette strain, we compared the S protein sequences of several IBV strains. The Beaudette strain was found to contain a putative heparan sulfate (HS)-binding site, indicating that the Beaudette virus may use HS as a selective receptor. To ascertain the requirements of cell-surface HS for Beaudette infectivity, we assayed for infectivity in the presence of soluble heparin as a competitor and determined infectivity in mutant cell lines with no HS or glycosaminoglycan expression. Our results indicate that HS plays a role as an attachment factor for IBV, working in concert with other factors like sialic acid to mediate virus binding to cells, and may explain in part the extended tropism of IBV Beaudette.
authors.affiliation: Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Ikenna G
authors.initials: IG
authors.lastname: Madu
authors.forename: Victor C
authors.initials: VC
authors.lastname: Chu
authors.forename: Hwajin
authors.initials: H
authors.lastname: Lee
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Regan
authors.forename: Beverley E
authors.initials: BE
authors.lastname: Bauman
authors.forename: Gary R
authors.initials: GR
authors.lastname: Whittaker
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002460:Cell Line; D002642:Chick Embryo; D019295:Computational Biology; D006224:Cricetinae; D006497:Heparan Sulfate / Q000378:metabolism*; D001351:Infectious bronchitis virus / Q000145:classification / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000378:metabolism*; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D006497:Heparan Sulfate; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; C578557:spike glycoprotein, SARS-CoV; C578553:spike protein, mouse hepatitis virus