Document 0866
 DOCN  M9540866
 TI    HIV-1 Tat protein is able to efficiently transactivate the HIV-2 LTR
       through a TAR RNA element lacking both dinucleotide bulge binding sites.
 DT    9504
 AU    Rhim H; Rice AP; Division of Molecular Virology, Baylor College of
       Medicine,; Houston, Texas 77030.
 SO    Virology. 1995 Jan 10;206(1):673-8. Unique Identifier : AIDSLINE
       MED/95133208
 AB    Each of the two stem-loop structures in the HIV-2 TAR (TAR-2) RNA
       element contains a dinucleotide bulge that specifies a binding site in
       vitro for the HIV-2 Tat transactivator protein. A TAR-2 RNA with both
       bulges deleted is very weakly transactivated in vivo by the HIV-2 Tat
       protein. To gain insight into general features of Tat protein:TAR RNA
       interactions, we have analyzed the significance of the dinucleotide
       bulges in TAR-2 RNA for in vitro binding and in vivo transactivation by
       the related HIV-1 Tat protein. The HIV-1 Tat protein has been shown
       previously to bind efficiently to wild-type TAR-2 RNA and fully
       transactivates the HIV-2 LTR. We found that the 5' proximal bulge and
       the 3' distal bulge appear to specify a high and low affinity binding
       site in vitro, respectively, for the HIV-1 Tat protein. Wild-type TAR-2
       RNA was found to be able to bind HIV-1 Tat proteins simultaneously at
       each bulge binding site in vitro. A TAR-2 RNA with both bulges deleted
       was greatly defective for in vitro binding by the HIV-1 Tat protein.
       Surprisingly, the TAR-2 RNA with both bulges deleted was efficiently
       transactivated in vivo by the HIV-1 Tat protein, indicating that the
       HIV-1 Tat protein (but not HIV-2 Tat protein) is able to strongly
       activate transcription of a TAR RNA with no apparent bulge binding site.
 DE    Base Sequence  Binding Sites  Gene Products, tat/*PHYSIOLOGY  Hela Cells
       Human  *HIV Long Terminal Repeat  HIV-2/*GENETICS  Molecular Sequence
       Data  Nucleic Acid Conformation  Nucleotides/METABOLISM  RNA,
       Viral/CHEMISTRY/*GENETICS/METABOLISM  Support, U.S. Gov't, P.H.S.
       *Trans-Activation (Genetics)  JOURNAL ARTICLE

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