       Document 0299
 DOCN  M9460299
 TI    Intracellular analysis of in vitro modified HIV Tat protein.
 DT    9404
 AU    Koken SE; Greijer AE; Verhoef K; van Wamel J; Bukrinskaya AG; Berkhout
       B; Department of Virology, University of Amsterdam, The Netherlands.
 SO    J Biol Chem. 1994 Mar 18;269(11):8366-75. Unique Identifier : AIDSLINE
       MED/94179219
 AB    Human immunodeficiency viruses HIV-1 and HIV-2 encode a Tat protein that
       specifically activates transcription from the viral long terminal
       repeat. To characterize the properties of the Tat proteins, we have
       expressed them in Escherichia coli. The purified Tat protein was
       biochemically analyzed and tested for activity upon electroporation into
       human cell lines. This protein electroporation was used for the
       intracellular analysis of in vitro modified Tat protein. Our results
       indicate that the transcriptionally active form of the Tat protein is a
       monomer. Furthermore, we found that Tat activity is dramatically
       inhibited by preincubation of the protein with strongly reducing agents.
       In contrast, no inhibitory effect was measured upon incubation with
       metal-chelating reagents. These results suggest that the cysteine
       residues of Tat are involved in the formation of intramolecular
       disulfide bonds.
 DE    Base Sequence  Cadmium/METABOLISM/PHARMACOLOGY  Cell Line
       Chloramphenicol Acetyltransferase/METABOLISM  Dithionitrobenzoic Acid
       Dithiothreitol/PHARMACOLOGY  DNA Primers  Electroporation  Gene
       Products, tat/BIOSYNTHESIS/ISOLATION & PURIF/*METABOLISM  Glutathione
       Transferases/BIOSYNTHESIS/ISOLATION & PURIF/  METABOLISM  Human
       HIV-1/*METABOLISM  HIV-2/*METABOLISM  Kinetics  Molecular Sequence Data
       Oxidation-Reduction  Polymerase Chain Reaction  Recombinant Fusion
       Proteins/BIOSYNTHESIS/ISOLATION & PURIF/  METABOLISM  RNA-Binding
       Proteins/METABOLISM  Sulfhydryl Compounds/PHARMACOLOGY  Support,
       Non-U.S. Gov't  T-Lymphocytes  Transfection
       Zinc/METABOLISM/PHARMACOLOGY  JOURNAL ARTICLE

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

