title: Equine infectious anemia virus Gag polyprotein late domain specifically recruits cellular AP-2 adapter protein complexes during virion assembly.
abstract: We have identified an interaction between the equine infectious anemia virus (EIAV) late assembly domain and the cellular AP-2 clathrin-associated adapter protein complex. A YXXL motif within the EIAV Gag late assembly domain was previously characterized as a sequence critical for release of assembling virions. We now show that this YXXL sequence interacts in vitro with the AP-50 subunit of the AP-2 complex, while the functionally interchangeable late assembly domains carried by the Rous sarcoma virus p2b protein and human immunodeficiency virus type 1 p6 protein, which utilize PPPY and PTAPP L domains, respectively, do not bind AP-50 in vitro. In addition, EIAV late domain mutants containing mutations that have previously been shown to abrogate budding also exhibit marked decreases in AP-50 binding efficiencies. A role for AP-2 complex in viral assembly is supported by immunofluorescence analysis of EIAV-infected equine dermal cells demonstrating specific colocalization of the alpha adaptin subunit of AP-2 with the EIAV p9 protein at sites of virus budding on the plasma membrane. These data provide strong evidence that EIAV utilizes the cellular AP-2 complex to accomplish virion assembly and release.
authors.affiliation: Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Puffer
authors.forename: S C
authors.initials: SC
authors.lastname: Watkins
authors.forename: R C
authors.initials: RC
authors.lastname: Montelaro
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000502:physiology*; D015683:Gene Products, gag / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D006801:Humans; D004860:Infectious Anemia Virus, Equine / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D046911:Macromolecular Substances; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000737:chemistry / Q000502:physiology*
chemical_list: D004268:DNA-Binding Proteins; D015683:Gene Products, gag; D046911:Macromolecular Substances; D011993:Recombinant Fusion Proteins; D050656:Transcription Factor AP-2; D014157:Transcription Factors