       Document 0107
 DOCN  M9610107
 TI    Functional analysis of HIV-1 Vpr: identification of determinants
       essential for subcellular localization.
 DT    9601
 AU    Mahalingam S; Collman RG; Patel M; Monken CE; Srinivasan A; Department
       of Microbiology and Immunology, Jefferson Cancer; Institute, Thomas
       Jefferson University, Philadelphia,; Pennsylvania 19107, USA.
 SO    Virology. 1995 Oct 1;212(2):331-9. Unique Identifier : AIDSLINE
       MED/96010205
 AB    Vpr is a conserved HIV-1 auxiliary protein that localizes to the nuclear
       region of cells. Vpr is also present in virions, and it is directed into
       the assembling virus when coexpressed with Gag. Each of these two
       localization activities may be important for Vpr function, and we
       recently identified regions of Vpr that are critical for virion
       incorporation. In this study we analyzed the Vpr domains involved in
       subcellular localization. Immunofluorescence staining of transfected
       cells showed that wild-type Vpr localized exclusively to the nuclear
       region. Mutations in the N-terminal domain that were designed to disrupt
       a predicted alpha-helical structure resulted in aberrant localization,
       while conservative substitutions showed a wild-type pattern. A region in
       the central portion of the protein also has the potential for helical
       structure, and mutagenesis of two conserved amino acids in this domain
       (A59, H71) impaired localization, while substitution of a third (Q65)
       did not. In contrast, neither the conserved Gly and Cys at positions
       75-76 nor the C-terminal basic residues (R87, K95) were necessary for
       nuclear localization. In addition, two-residue insertions within and
       between the two putative helices disrupted localization but insertion in
       the C-terminal region did not. Thus, Vpr's subcellular localization
       function depends on the two putative helical domains but is independent
       of the conserved Gly-Cys motif and of specific C-terminal basic
       residues.
 DE    Amino Acid Sequence  Amino Acids/PHYSIOLOGY  Cell Nucleus/*CHEMISTRY
       Conserved Sequence  Gene Products, vpr/*ANALYSIS/CHEMISTRY/GENETICS
       Hela Cells  Human  HIV-1/*CHEMISTRY/GENETICS  Molecular Sequence Data
       Mutation  Protein Structure, Secondary  Support, Non-U.S. Gov't
       Support, U.S. Gov't, P.H.S.  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

