title: Structure of the Fab-labeled "breathing" state of native poliovirus.
abstract: At 37°C, the structure of poliovirus is dynamic, and internal polypeptides VP4 and N terminus of VP1 (residues 1 to 53) externalize reversibly. An Fab fragment of a monospecific antibody, which binds to residues 39 to 55 of VP1, was utilized to locate the N termini of VP1 in native (160S) particles in this "breathing" state. Fab and virus were mixed and imaged via cryogenic electron microscopy. The resulting reconstruction showed the capsid expands similarly to the irreversibly altered cell entry intermediate (135S) particle, but the N terminus of VP1 is located near the 2-fold axes, instead of the "propeller tip" as in 135S particles.
authors.affiliation: Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Lin
authors.forename: Lily Y
authors.initials: LY
authors.lastname: Lee
authors.forename: Merja
authors.initials: M
authors.lastname: Roivainen
authors.forename: David J
authors.initials: DJ
authors.lastname: Filman
authors.forename: James M
authors.initials: JM
authors.lastname: Hogle
authors.forename: David M
authors.initials: DM
authors.lastname: Belnap
mesh_terms: D002213:Capsid / Q000737:chemistry; D036022:Capsid Proteins / Q000737:chemistry*; D020285:Cryoelectron Microscopy; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000032:analysis*; D008958:Models, Molecular; D011051:Poliomyelitis / Q000821:virology; D017955:Poliovirus / Q000737:chemistry* / Q000378:metabolism
chemical_list: D036022:Capsid Proteins; D007140:Immunoglobulin Fab Fragments; C442540:VP1 protein, Poliovirus