title: Cell surface expression of the HIV-1 envelope glycoproteins is directed from intracellular CTLA-4-containing regulated secretory granules.
abstract: The envelope glycoprotein (Env) of HIV-1 is incorporated into virions that bud from the cell surface of infected T cells. With immunofluorescence microscopy and subcellular membrane fractionation techniques, the intracellular fate of Env in the secretory pathway of HIV-1-infected T cells was evaluated. Rather than trafficking constitutively from the Golgi to the cell surface, Env is directed to intracellular CTLA-4-containing granules, whose recruitment to the cell surface is regulated. The use of the regulated pathway for intracellular Env storage before virion assembly holds implications for the staging of Env exposure at the cell surface of infected cells and of coordinating HIV virion assembly.
authors.affiliation: Department of Cellular and Structural Biology, Program in Cell and Developmental Biology, University of Colorado Health Sciences Center, Box B-111, 4200 East Ninth Avenue, Denver, CO 80262, USA.
authors.forename: Luis R
authors.initials: LR
authors.lastname: Miranda
authors.forename: Brian C
authors.initials: BC
authors.lastname: Schaefer
authors.forename: Abraham
authors.initials: A
authors.lastname: Kupfer
authors.forename: Zixin
authors.initials: Z
authors.lastname: Hu
authors.forename: Alex
authors.initials: A
authors.lastname: Franzusoff
mesh_terms: D000069594:Abatacept; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000378:metabolism*; D015153:Blotting, Western; D060908:CTLA-4 Antigen; D002458:Cell Fractionation / Q000379:methods; D002460:Cell Line; D002462:Cell Membrane / Q000648:ultrastructure / Q000821:virology; D002499:Centrifugation, Density Gradient / Q000379:methods; D015967:Gene Expression Regulation, Viral; D006056:Golgi Apparatus / Q000648:ultrastructure / Q000821:virology; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D018796:Immunoconjugates; D007150:Immunohistochemistry; D022142:Secretory Vesicles / Q000502:physiology* / Q000648:ultrastructure / Q000821:virology; D013601:T-Lymphocytes; D014759:Viral Envelope Proteins / Q000235:genetics*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; D018796:Immunoconjugates; D014759:Viral Envelope Proteins; D000069594:Abatacept