title: Genetic analysis of the localization of APOBEC3F to human immunodeficiency virus type 1 virion cores.
abstract: Members of the APOBEC3 family of cytidine deaminases vary in their proportions of a virion-incorporated enzyme that is localized to mature retrovirus cores. We reported previously that APOBEC3F (A3F) was highly localized into mature human immunodeficiency virus type 1 (HIV-1) cores and identified that L306 in the C-terminal cytidine deaminase (CD) domain contributed to its core localization (C. Song, L. Sutton, M. Johnson, R. D'Aquila, J. Donahue, J Biol Chem 287:16965-16974, 2012, http://dx.doi.org/10.1074/jbc.M111.310839). We have now determined an additional genetic determinant(s) for A3F localization to HIV-1 cores. We found that one pair of leucines in each of A3F's C-terminal and N-terminal CD domains jointly determined the degree of localization of A3F into HIV-1 virion cores. These are A3F L306/L368 (C-terminal domain) and A3F L122/L184 (N-terminal domain). Alterations to one of these specific leucine residues in either of the two A3F CD domains (A3F L368A, L122A, and L184A) decreased core localization and diminished HIV restriction without changing virion packaging. Furthermore, double mutants in these leucine residues in each of A3F's two CD domains (A3F L368A plus L184A or A3F L368A plus L122A) still were packaged into virions but completely lost core localization and anti-HIV activity. HIV virion core localization of A3F is genetically separable from its virion packaging, and anti-HIV activity requires some core localization.
  
  
  OBJECTIVE
  Specific leucine-leucine interactions are identified as necessary for A3F's core localization and anti-HIV activity but not for its packaging into virions. Understanding these signals may lead to novel strategies to enhance core localization that may augment effects of A3F against HIV and perhaps of other A3s against retroviruses, parvoviruses, and hepatitis B virus.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Donahue
authors.affiliation: Center for Human Genetics Research, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
authors.forename: Rebecca T
authors.initials: RT
authors.lastname: Levinson
authors.affiliation: Center for Structural Biology and Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA.
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Sheehan
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
authors.forename: Lorraine
authors.initials: L
authors.lastname: Sutton
authors.affiliation: Division of Infectious Diseases and Northwestern HIV Translational Research Center, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
authors.forename: Harry E
authors.initials: HE
authors.lastname: Taylor
authors.affiliation: Center for Structural Biology, Institute for Chemical Biology, and Departments of Chemistry, Pharmacology, and Biomedical Informatics, Vanderbilt University, Nashville Tennessee, USA.
authors.forename: Jens
authors.initials: J
authors.lastname: Meiler
authors.affiliation: Division of Infectious Diseases and Northwestern HIV Translational Research Center, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA richard.daquila@northwestern.edu chisu.song@northwestern.edu.
authors.forename: Richard T
authors.initials: RT
authors.lastname: D'Aquila
authors.affiliation: Division of Infectious Diseases and Northwestern HIV Translational Research Center, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA richard.daquila@northwestern.edu chisu.song@northwestern.edu.
authors.forename: Chisu
authors.initials: C
authors.lastname: Song
mesh_terms: D002460:Cell Line; D043525:Cytosine Deaminase / Q000032:analysis* / Q000235:genetics* / Q000276:immunology; D004252:DNA Mutational Analysis; D017930:Genes, Reporter; D015497:HIV-1 / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D006801:Humans; D008156:Luciferases / Q000032:analysis; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D013194:Staining and Labeling; D019065:Virus Assembly; D001616:beta-Galactosidase / Q000032:analysis
chemical_list: D008156:Luciferases; D001616:beta-Galactosidase; C492906:APOBEC3F protein, human; D043525:Cytosine Deaminase