       Document 0842
 DOCN  M9540842
 TI    Expression kinetics and subcellular localization of HIV-1 regulatory
       proteins Nef, Tat and Rev in acutely and chronically infected lymphoid
       cell lines.
 DT    9504
 AU    Ranki A; Lagerstedt A; Ovod V; Aavik E; Krohn KJ; Department of
       Dermatology and Venereology, University of; Helsinki, Finland.
 SO    Arch Virol. 1994;139(3-4):365-78. Unique Identifier : AIDSLINE
       MED/95134092
 AB    Information concerning the expression kinetics and subcellular
       localization of HIV regulatory proteins is of importance in
       understanding the viral pathogenesis and may be relevant for drug and
       vaccine development, as well. We have used combined immunocytochemistry
       and in situ hybridization to study firstly, the order of expression of
       regulatory HIV-1 proteins Nef, Rev and Tat in relation to non-spliced
       and spliced mRNA expression and secondly, the subcellular localization
       of these proteins in acutely and chronically infected human T-cell
       lines. We used monoclonal antibodies against HIV-1 Nef, Tat, Rev and
       gp160, and RNA probes reacting either with all mRNAs (nef) or only with
       the full-length mRNA (gag-pol). In acutely infected MT-4 and H9 cells,
       four distinct phases of infection could be defined. In the first phase
       lasting from 0 to 6 h post-infection, only incoming virus could be
       demonstrated by gp160 immunocytochemistry. During the second, regulatory
       phase (6-9 h), abundant cytoplasmic expression of Nef, Rev and Tat
       proteins and a positive in situ RNA hybridization with the nef probe was
       seen, while the in situ hybridization with full-length mRNA probe and
       immunohistochemistry for gp160 were still negative. The productive phase
       (12-48 h) was characterized by abundant expression of full-length mRNA
       and gp160, and by the nuclear localization of Nef and Tat proteins. In
       contrast, an antibody that recognized the RRE binding region of the Rev
       protein localized Rev in the cytoplasm both during the regulatory and
       productive phase. During the fourth, cytopathic phase, the expression of
       mRNA or viral proteins decreased and the regulatory proteins studied
       were again mainly localized in the cytoplasm. Based on the results, we
       speculate that HIV Nef may function as a nuclear factor, and that Tat is
       possibly bound by cellular proteins before its transport to the nucleus.
 DE    Cell Death  Cell Line  Cell Nucleus/CHEMISTRY  Cytopathogenic Effect,
       Viral  Cytoplasm/CHEMISTRY  Gene Expression  Gene Products,
       nef/ANALYSIS/*BIOSYNTHESIS/GENETICS  Gene Products,
       rev/ANALYSIS/*BIOSYNTHESIS/GENETICS  Gene Products,
       tat/ANALYSIS/*BIOSYNTHESIS/GENETICS  Human
       HIV-1/GENETICS/METABOLISM/*PHYSIOLOGY  In Situ Hybridization  Kinetics
       RNA, Messenger/GENETICS/METABOLISM  RNA, Viral/GENETICS/METABOLISM
       Support, Non-U.S. Gov't  T-Lymphocytes/METABOLISM/*VIROLOGY  JOURNAL
       ARTICLE

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

