title: Yaba-like disease virus protein Y144R, a member of the complement control protein family, is present on enveloped virions that are associated with virus-induced actin tails.
abstract: Yaba-like disease virus (YLDV) is a yatapoxvirus, a group of slow-growing poxviruses from primates. Analysis of the growth cycle of YLDV in tissue culture showed that maximum virus titres were reached 3 days post-infection and at this time only 3.3 % of infectious progeny was extracellular. The intracellular and extracellular virions have different buoyant densities and are separable on CsCl density gradients. They are also distinguishable by electron microscopy with the extracellular virions having an additional lipid envelope. In YLDV-infected cells, thick actin bundles with virions at their tips were seen protruding from the cell surface, despite the fact that YLDV lacks a protein comparable to Vaccinia virus A36R, which is required for VV-induced actin tail formation. In addition to these observations, the YLDV gene Y144R was characterized. This gene is predicted to encode a transmembrane protein containing three short consensus repeat (SCR) motifs common to members of the complement control protein family. Antibody generated against recombinant Y144R recognized products of 36, 41 and 48-55 kDa in YLDV-infected cells and purified extracellular enveloped virus (EEV) but not intracellular mature virus (IMV). Y144R protein is a glycoprotein with type I membrane topology that is synthesized early and late during infection. By immunoblot, indirect immunofluorescence and immuno-cryoelectron microscopy the Y144R protein was detected on the intracellular enveloped virus (IEV), cell-associated enveloped virus (CEV) and EEV. This represents the first study of a YLDV IEV, CEV and EEV protein at the molecular level.
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.|Department of Virology, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
authors.forename: Mansun
authors.initials: M
authors.lastname: Law
authors.affiliation: Department of Virology, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Hollinshead
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
authors.forename: Han-Joo
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.|Department of Virology, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
authors.forename: Geoffrey L
authors.initials: GL
authors.lastname: Smith
mesh_terms: D000199:Actins / Q000378:metabolism*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D003165:Complement System Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D017464:Receptors, Complement 3d; D016415:Sequence Alignment; D012995:Solubility; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014771:Virion / Q000737:chemistry*; D014999:Yaba monkey tumor virus / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000199:Actins; D017464:Receptors, Complement 3d; D014759:Viral Envelope Proteins; D003165:Complement System Proteins